Restoration-Mini

General Discussion => Events and Mini Clubs => Topic started by: MiniDave on September 01, 2018, 08:29:35 PM

Title: New Dyno Day at Prather Racing
Post by: MiniDave on September 01, 2018, 08:29:35 PM
I'm setting up a play day at a great local shop to run our cars on the dyno. The fellows who run this shop are extremely experienced with old English cars and carbs. The results from our first Dyno there were incredible. Not every car benefited but those that did made significant gains and really run well now. so grab your car and come play with us....

Friday, Oct 5th

Prather racing is on the southeast side of Topeka, Ks and there are plenty of hotels in the area -

Jesse Prather Motorsports
4950 SE Adams
Topeka, KS 66609
785-249-0284

There are a lot of very reasonably priced hotels near the shop and Heartland Park road course is right down the road.

Details are we'll show up at the shop about 8 am and he'll load the first car on the dyno. Each run takes between 20 min to a half hour and as we get closer to the date I'll set up a schedule. Everyone is welcome to hang out at the shop while the other cars are being run on the dyno - I find it fun to see what kinds of results the different cars bring. Right now my plan is to have all the classics run first, there may be some new MINIs interesting cars in the afternoon.

We'll break for lunch around noon and start back up about 1-ish.

I was hoping there might be an event at the nearby Heartland Park Road course that weekend but it appears not, however it's only a few miles down the road if anyone wants to go see the track - I've done probably 500 laps there over the years!


Right now the following people are going to go, subject to change: So we have 2-3 possible openings left......

Dave Craven          Mini
Bruce Kennedy       Mini
Stan Chen             Mini
Gordon Fitch          Mini, Sprite
Seth Weaver          Mini
Dan Stoughton       Mini
Michael Playle         Mini
Deighton Brunson   Mini
John Styers            Jensen Healy
Clancy Schmidt       Race Sprite
Title: Re: New Dyno Day at Prather Racing
Post by: 94touring on September 01, 2018, 09:03:19 PM
Probably change me to Fd3s Rx7.  Should know in the coming week if I have the day off.
Title: Re: New Dyno Day at Prather Racing
Post by: MiniDave on September 10, 2018, 10:57:12 AM
I confirmed with Jesse this morning that we would be there on Oct 5th, he's looking forward to it. He says he has plenty of needles in stock if we need them and he's confident he can gain something on pretty much every car - should be a fun and beneficial day for all!
Title: Re: New Dyno Day at Prather Racing
Post by: MiniDave on September 10, 2018, 03:13:19 PM
For those travelling up from the south, there is a Wyndham Super 8 just a few blocks south of JP Motorsports at 5922 SW Topeka Blvd, Topeka, KS 66619 (Forbes Field) Just take the Topeka Blvd Exit off 75 and go a few blocks further north and you're there. Plenty of parking space for trailers and such.

For those coming up I-35, then I-335 take the 470 exit then go south on Topeka blvd a little ways and you're there.
Title: Re: New Dyno Day at Prather Racing
Post by: MPlayle on September 15, 2018, 03:08:18 PM
Rooms booked for the trip.  Staying at the suggested Super-8 in Topeka.

Edit:
What is the individual (or per car) dyno cost?  Do we prepay that to someone and if so, who?

Title: Re: New Dyno Day at Prather Racing
Post by: BruceK on September 15, 2018, 05:12:10 PM
I'm booked there too.

I believe in another thread Dave said the cost was about $110 or so  depending on the number of cars done.
Title: Re: New Dyno Day at Prather Racing
Post by: MiniDave on September 16, 2018, 02:59:41 PM
$100 each will cover it, pay me when we get there and if there are less than 10 I'll make up the difference.
Title: Re: New Dyno Day at Prather Racing
Post by: MiniDave on September 18, 2018, 06:52:13 AM
Before we get to Prather Racing, if you can - make a note of which needle and spring you're running, also what you have your timing set at. If you don't know it's no biggy, we'll check it anyway but it's good to know where things are set for the baseline runs.

Jesse will have Kent's box of needles and jets and I'll have a few of the more common needle sizes for the HIF carbs too.

Still have a couple of spots open for anyone who hasn't committed....

Based on replies I'll be making up an order of run list next week. If someone wants to go first or last or whatever, just let me know. Generally my thought is to have the out of towners go first and the locals go last. If you have a time crunch, let me know and I'll put you at the top of the line up and you can leave as soon as you like, or hang out all day with us. I expect we'll all head for dinner somewhere after the last car has run and all are welcome.

I think this will be a great opportunity for all of us to get to know our fellow RM'ers - I'm looking forward to seeing all of you there!
Title: Re: New Dyno Day at Prather Racing
Post by: Scargo on September 18, 2018, 10:18:37 AM
Makes me wish I lived in Kansas.
Title: Re: New Dyno Day at Prather Racing
Post by: gr8kornholio on September 18, 2018, 10:56:54 AM
Makes me wish I had a whole car.
Title: Re: New Dyno Day at Prather Racing
Post by: MiniDave on September 18, 2018, 11:04:00 AM
Quote from: Scargo on September 18, 2018, 10:18:37 AM
Makes me wish I lived in Kansas.

Uh.......no you don't.     ;D

But you could live somewhere close enough to join us!  77.gif
Title: Re: New Dyno Day at Prather Racing
Post by: 94touring on September 18, 2018, 01:00:17 PM
Tulsa!
Title: Re: New Dyno Day at Prather Racing
Post by: MiniDave on September 22, 2018, 07:54:46 AM
So Michael, when you tow the Moke up do you remove the top? Lay down the windshield?
Title: Re: New Dyno Day at Prather Racing
Post by: MPlayle on September 22, 2018, 09:03:41 AM
I have not towed this Moke anywhere yet. 

The first Moke I had I flat towed behind a 2002 Mini Cooper-S.  I removed the top on it, but left the windshield (they are not hinged and do not really lay flat.  The top had a fixed rear window that would make the top act as a "drag chute".

This Moke, I had the top made with a roll up rear window.  I could go either way on the top, but most likely to remove it.  I have not decided whether to remove the windshield when towing.

Title: Re: New Dyno Day at Prather Racing
Post by: MiniDave on September 26, 2018, 10:39:06 AM
Right now the weather looks perfect - mid 50's in the am going up to a high of 68 in the afternoon.

Seth has asked if he can go at/near the front of the line as he has a Dr appt later, anyone else need an early T-time?

Gordon has two cars to bring, so we'll let him go early too so he can drive back to Lawrence and swap cars.
Title: Re: New Dyno Day at Prather Racing
Post by: MiniDave on September 26, 2018, 04:43:30 PM
Bonus!

Clancy is going to bring his race Sprite over in the afternoon for a few pulls too.....lets make some noise!   77.gif

As of now we are full up, but Jesse says we'll get them all done, no problem.
Title: Re: New Dyno Day at Prather Racing
Post by: MiniDave on September 27, 2018, 08:31:08 AM
Bonus #2!

Russ Foust will be stopping by in his Clubby with the now-supercharged Acura V-6 in it!
Title: Re: New Dyno Day at Prather Racing
Post by: MPlayle on September 27, 2018, 11:00:27 AM
With all the suped up cars showing up, I wonder if my Moke is going to have adequacy issues?

Title: Re: New Dyno Day at Prather Racing
Post by: MiniDave on September 27, 2018, 11:11:03 AM
My tired old car won't be a whole lot better - stock 1275 AFIK.....

We will make it the best it can be - and it will be very drivable when done.
Title: Re: New Dyno Day at Prather Racing
Post by: 94touring on September 27, 2018, 11:34:34 AM
The 50 miles I just put on mine to begin breaking it in says I'm going to be dyno king.  At least in the modified mini street 1275 class.   ;D
Title: Re: New Dyno Day at Prather Racing
Post by: MiniDave on September 27, 2018, 05:55:03 PM
Should we plan to meet up for dinner Thurs evening? I'm thinking I may Super 8 it Thursday too, that way I don't have to get up so early Friday to make the hour's drive and get there by 7:30 to help get set up. I'll see if Jesse has a recommendation for a restaurant.....
Title: Re: New Dyno Day at Prather Racing
Post by: BruceK on September 27, 2018, 05:59:20 PM
Sounds good.  I'm in.
Title: Re: New Dyno Day at Prather Racing
Post by: gr8kornholio on September 27, 2018, 06:05:32 PM
Jealousy is running rampant on my end.   :(   Would love to see the numbers my 1380 could make.  :-\
Title: Re: New Dyno Day at Prather Racing
Post by: stan360 on September 27, 2018, 06:15:26 PM
Hey Dave,
If you are organizing slots for us with the times, I am not an early riser  16.gif, maybe I could go later in the order of  the classic mini bunch.
Title: Re: New Dyno Day at Prather Racing
Post by: MiniDave on September 27, 2018, 06:17:42 PM
You're on Stan, no problem......let's see I'll schedule you at .....8:30 OK?   ;D ;D

Nah, just let me know when you're on your way. Of course you'll miss some of the first runs.....
Title: Re: New Dyno Day at Prather Racing
Post by: 94touring on September 27, 2018, 06:52:27 PM
Bruce what time are you thinking you'll be in Tulsa/Ramoma?
Title: Re: New Dyno Day at Prather Racing
Post by: BruceK on September 27, 2018, 07:29:30 PM
I haven't discussed a start time from Plano with Michael, but if we leave at 7:30am, we should be at your shop by 1pm or so, factoring in stops for gas, etc.   Will that work?   

Michael is OK with you?
Title: Re: New Dyno Day at Prather Racing
Post by: 94touring on September 27, 2018, 07:41:47 PM
Earliest I land in Tulsa is 1130am.  Takes me roughly 30 minutes to get to the shop from the airport.  So that should work.
Title: Re: New Dyno Day at Prather Racing
Post by: MiniDave on September 28, 2018, 07:02:22 AM
OK, Jesse came thru with a recommendation - dinner Thurs night will be at the "Blind Tiger Restaurant and Brewery" on SW 37th, just a mile or two from the Superduper 8 hotel.....say 6 pm?
Title: Re: New Dyno Day at Prather Racing
Post by: MPlayle on September 28, 2018, 07:26:30 AM
Quote from: BruceK on September 27, 2018, 07:29:30 PM
I haven't discussed a start time from Plano with Michael, but if we leave at 7:30am, we should be at your shop by 1pm or so, factoring in stops for gas, etc.   Will that work?   

Michael is OK with you?

Sounds OK to me.

Title: Re: New Dyno Day at Prather Racing
Post by: 94touring on September 28, 2018, 05:26:28 PM
I think I'm all set.  Changed oil in the car and truck.  Setup the winch on the trailer.  Last drive of the day on the mini the roll pin on the shift lingage came half way out, rendering 1st and 2nd inop.  Got it rolling down a hill and popped it in 3rd to quickly discover this once back to the shop.  It's secure enough for now till the new pin gets in.
Title: Re: New Dyno Day at Prather Racing
Post by: MPlayle on September 28, 2018, 08:12:34 PM
Safety wire through the pins?

Title: Re: New Dyno Day at Prather Racing
Post by: MiniDave on September 28, 2018, 08:41:56 PM
A regular screw type hose camp would be an easy way to guarantee that it wouldn't come out again. But it might be too heavy!   ;D ;D
Title: Re: New Dyno Day at Prather Racing
Post by: 94touring on September 29, 2018, 02:31:24 AM
Safety wire through the pin like aircraft use isn't a bad idea.  I even thought a piece of gorilla tape wrapped around would keep it from sliding out.  Hose clamp definetly too heavy  ;D Though the screw part may hit the casing too.  Not a lot of room down there.  I do enjoy how easy it is to push the car around given the weight! 
Title: Re: New Dyno Day at Prather Racing
Post by: BruceK on September 29, 2018, 07:52:22 AM
I'm kinda surprised the pin is that loose.  My experience is they are major PIA to knock out.  Which is why I fitted a quick-release coupler. 

And... I used safety wire with it.  restorationmini.com/forum/index.php?topic=1232.msg18924#msg18924 (http://www.restorationmini.com/forum/index.php?topic=1232.msg18924#msg18924)

(http://www.restorationmini.com/forum/index.php?action=dlattach;topic=1232.0;attach=6001;image)
Title: Re: New Dyno Day at Prather Racing
Post by: 94touring on September 29, 2018, 08:54:02 AM
That's a cool setup.  I wonder if a new pin will be any better.  I may just safety wire what I have and call it a day.
Title: Re: New Dyno Day at Prather Racing
Post by: MiniDave on October 01, 2018, 03:17:47 PM
Bill Fisher from the Lawrence All British Car Club will be at the Dyno day to take pics and do a write up for the Newsletter. Bill has extensive graphics background and publishes the club's newsletter each month.....as several club members will be there it's a good time for a little write up. He's also an accomplished photographer so I hope to get some great shots of all our cars.
Title: Re: New Dyno Day at Prather Racing
Post by: 94touring on October 01, 2018, 03:38:21 PM
Does this mean I need to wash bugs off?
Title: Re: New Dyno Day at Prather Racing
Post by: MiniDave on October 01, 2018, 03:47:46 PM
Up to you!   ;D ;D ;D ;D

Weather forecast has changed considerably, now expecting sunny and 86*!
Title: Re: New Dyno Day at Prather Racing
Post by: 94touring on October 01, 2018, 04:08:44 PM
That will be nice! 

Yeah the grasshoppers and tarantulas were out in full force during breakin.  Bugs in the engine bay too.
Title: Re: New Dyno Day at Prather Racing
Post by: 94touring on October 03, 2018, 10:13:20 AM
The scheduling Gods have approved a drop request in my favor, so I will be home tonight rather in the morning (90% guaranteed). Bruce and Michael, are you planning lunch pre or post Ramoma?

Title: Re: New Dyno Day at Prather Racing
Post by: BruceK on October 03, 2018, 10:40:13 AM
Quote from: 94touring on October 03, 2018, 10:13:20 AM
The scheduling Gods have approved a drop request in my favor, so I will be home tonight rather in the morning (90% guaranteed). Bruce and Michael, are you planning lunch pre or post Ramoma?

We had not discussed it.   We spoke yesterday and discussed meeting up at 7am here and leaving shortly thereafter.  So that means we might get to you a bit sooner.  I'm sure we are open for lunch.  We can text you as we get moving along to let you know of our progress.
Title: Re: New Dyno Day at Prather Racing
Post by: MPlayle on October 03, 2018, 03:12:46 PM
I am totally flexible.

As Bruce indicated, the plan so far is to meet at my hotel in Plano at 7:00am and head up the road a bit, make a fuel stop, and head on up from there.

Bruce mentioned the most direct route is on a toll road.  I don't have toll tags, but we can juggle appropriately and/or do "pay-by-mail" if that is how they work.  I will probably be following him as he has been there at least once before.

Post an address for me to plug into my GPS as a backup.
Title: Re: New Dyno Day at Prather Racing
Post by: 94touring on October 03, 2018, 03:16:14 PM
Some are pay by mail, others are cash/coins.

Shop addy is 330 Keeler St. Ramona Ok 74061.  It's a straight shot on hwy75, hang a left at the flashing lights and first street on the left, a few houses down on the right. 
Title: Re: New Dyno Day at Prather Racing
Post by: MPlayle on October 03, 2018, 03:19:44 PM
I have a small jar of quarters with me.  No much for small bills at the moment.

Is it the same highway 75 coming out of Dallas?

Bruce,

Is that the route you were referring to as being part tollway?

Title: Re: New Dyno Day at Prather Racing
Post by: 94touring on October 03, 2018, 03:23:45 PM
Yeah 75 comes from Plano, but somewhere around Henryette you take 40 and 62 to join back up to 75.  Pretty fool proof. 
Title: Re: New Dyno Day at Prather Racing
Post by: 94touring on October 03, 2018, 03:26:11 PM
Here's what I'm looking at.
Title: Re: New Dyno Day at Prather Racing
Post by: BruceK on October 04, 2018, 05:14:05 AM
On the road!
Title: Re: New Dyno Day at Prather Racing
Post by: 94touring on October 04, 2018, 05:16:13 AM
Raining up here right now.  Hopefully stops for the journey north.
Title: Re: New Dyno Day at Prather Racing
Post by: MiniDave on October 04, 2018, 07:21:26 AM
Forecast for Topeka is 50* currently, going up to low 60's, 20% chance of rain...widely scattered showers.

Tomorrow - 30% chance - widely scattered showers, low 60's high upper 70's.

So, we might see some rain, but chances are better that we won't. 

Sure liking this 50* morning, it was mid 80's when I went to bed last night!

BTW, what happened to Michael's MINI Clubman?
Title: Re: New Dyno Day at Prather Racing
Post by: 94touring on October 04, 2018, 10:24:51 AM
Hope no rain, I don't have windows yet! Loaded up and ready to hit the road.
Title: Re: New Dyno Day at Prather Racing
Post by: BruceK on October 04, 2018, 11:31:15 AM
Michael and I are eating lunch with Dan after a quick tour of the shop. Just about to hit the road. 
Title: Re: New Dyno Day at Prather Racing
Post by: MPlayle on October 04, 2018, 05:55:50 PM
Quote from: MiniDave on October 04, 2018, 07:21:26 AM

BTW, what happened to Michael's MINI Clubman?

It did not instill a lot of confidence as a tow vehicle over the weekend going to/from the "All British" show in Round Rock, Tx.  I had been contemplating a better tow vehicle anyway, so made the change.

(My previous two "New" MINIs - a 2002 MCS and a 2008 Clubman-S - did better than the 20016 Clubman as tow vehicles.)

Title: Re: New Dyno Day at Prather Racing
Post by: MiniDave on October 04, 2018, 05:57:59 PM
That's Mark's Saucy Aussie in primer?

We're all buttoned down in the hotel for the evening after dinner at the Blind Tiger restaurant, Dan got some plastic over his windows, Michael got his top on the Moke and Bruce and I are locked up tight for the night. The four cars certainly attract a lot of attention!

Tomorrow we hit the dyno!
Title: Re: New Dyno Day at Prather Racing
Post by: BruceK on October 04, 2018, 06:30:21 PM
Yes, that's Mark's Oz Mini in primer.
Title: Re: New Dyno Day at Prather Racing
Post by: 94touring on October 04, 2018, 07:01:37 PM
Yellow filler primer ready for block sanding on Marks car. 
Title: Re: New Dyno Day at Prather Racing
Post by: gr8kornholio on October 04, 2018, 08:13:40 PM
Figured as much, looking good.  Glad y'all made it up there. Excited to hear the results.
Title: Re: New Dyno Day at Prather Racing
Post by: BruceK on October 05, 2018, 06:16:04 AM
Ready for the dyno runs.
Title: Re: New Dyno Day at Prather Racing
Post by: BruceK on October 05, 2018, 08:44:02 AM
More
Title: Re: New Dyno Day at Prather Racing
Post by: gr8kornholio on October 05, 2018, 08:46:12 AM
Looks like they are moving through them pretty fast.  Any crazy gains yet?
Title: Re: New Dyno Day at Prather Racing
Post by: BruceK on October 05, 2018, 08:47:19 AM
Small cars, big dyno.
Title: Re: New Dyno Day at Prather Racing
Post by: BruceK on October 05, 2018, 08:50:06 AM
Quote from: gr8kornholio on October 05, 2018, 08:46:12 AM
Looks like they are moving through them pretty fast.  Any crazy gains yet?

No crazy gains.   But Dan's new engine, not even run-in yet, made just a shade under 80hp at the wheels.  That was nice to see. 
Title: Re: New Dyno Day at Prather Racing
Post by: velopackrat on October 05, 2018, 09:57:58 AM
Can those of us in the bleachers now start converting HP at the wheels to HP at the flywheel?  Dan's 80HP should be like, I dunno... 200HP?
Seriously, 80hp sounds pretty strong.  What's his motor spec?
Title: Re: New Dyno Day at Prather Racing
Post by: jedduh01 on October 05, 2018, 10:26:04 AM
80 Hp is great!!  Exp for a 'road' engine.  As Dan mentions  its been FUN to start with and break in = now a number to know!

  I  dynoe'd my fresh 1275 ( pretty stock all around )  at MME way long ago = and in the 'average' of stock 1275's  62 to 68 Hp at the wheels among all the cars.  (At the wheels too)
      I remember being smack in the middle on point.   I know my engine runs well + works well, but knowing Dan has +20 HP its gonna be a real hoot!

Great to hear! 

Title: Re: New Dyno Day at Prather Racing
Post by: BruceK on October 05, 2018, 10:58:04 AM
Okay.  Crazy gain.
Title: Re: New Dyno Day at Prather Racing
Post by: gr8kornholio on October 05, 2018, 11:04:56 AM
Nice, who's the lucky winner?
Title: Re: New Dyno Day at Prather Racing
Post by: BruceK on October 05, 2018, 11:14:23 AM
Stan's Mini ! 
Title: Re: New Dyno Day at Prather Racing
Post by: BruceK on October 05, 2018, 11:35:12 AM
More
Title: Re: New Dyno Day at Prather Racing
Post by: 94touring on October 05, 2018, 02:58:32 PM
I'll post engine specs when I'm not driving.

Title: Re: New Dyno Day at Prather Racing
Post by: 94touring on October 05, 2018, 03:41:07 PM
Dyno graph.  One funny thing was seeing the difference between my car in 4th and the others.  My rpms go up quick! Jesse starting running everyone in 3rd gear, which did add an extra horse or two it seemed.  So maybe I could have hit 81.

Specs:
1275 +40 with 10:3:1 slipper pistons
Kent 266 cam
1.4 rockers
KC super sport stage 3 head
Maniflow stage 2 headers
Rc 40 twin box exhaust
Maniflow twin carb fancy intake manifold
Hs4 twin carbs with long ram pipes
Csi 16 point electric dizzy on curve 7
Flame thrower coil
Heat range 8 plugs gapped 30
Lightest verto flywheel available from MED
Turbo clutch.
Title: Re: New Dyno Day at Prather Racing
Post by: MiniDave on October 05, 2018, 03:48:03 PM
There's still some very fine tuning that can be done, but look at the HP curve - it just keeps going up - if he'd gone to 6500 I'll bet there's a few more HP in there. The car is super fast!

Just for comparison, Kent Prather's racing 1275 (more like 1300) is now up to 152hp (crank) on a single weber!
Title: Re: New Dyno Day at Prather Racing
Post by: 94touring on October 05, 2018, 05:58:59 PM
Dave post up your stock 1275 for a comparison.
Title: Re: New Dyno Day at Prather Racing
Post by: MiniDave on October 05, 2018, 06:43:37 PM
I'll have to go scan it in, but the numbers were 52.5 hp and 61.5 torques, which tailed off dramatically over 5K rpm.
Title: Re: New Dyno Day at Prather Racing
Post by: 94touring on October 05, 2018, 06:59:50 PM
Just unloaded the mini at the shop.  Time to go shower exhaust fumes off me.
Title: Re: New Dyno Day at Prather Racing
Post by: stan360 on October 05, 2018, 08:43:07 PM
Thanks so much for making the dyno day happen. Sorry I couldn't stay longer as I was trying to sort a friends tire troubles too.  It was so cool to see how  the dyno makes the tune  up process easier and the mini is running great on the ride home. I did discover that in a downpour I have a slight windshield seal leak and since I completely forgot Dave telling me to put  a lock nut on the larger nut covering the throw out plunger I luckily found that nut resting on subframe while I was cleaning my valve cover oil spray. Glad that was just a small problem, missing screw, as I usually look under bonnet before I drive and didn't today. 4 days ago on last drive it was ok so it may have fell out on my crazy drive to T town. It was nice to put some faces to some minis too. Nice to meet you Bruce ! Best driving day I have had yet . Many thanks . I wished I got to scope out Dan's car a bit more but the rain was a bit much during that time , I did get a look at the radius arms and rear brakes and wished I had those , super cool
Title: Re: New Dyno Day at Prather Racing
Post by: Vikram on October 06, 2018, 02:54:45 AM
Awesome. I've been looking for a reliable dyno thread for Mini's for so long, and this is it. When Dave posts the stock 1275 graph it will be really interesting to see the comparison to Dan's motor.

Dan, I assume power loss through transmission is now your biggest restrictor? Straight cut gears next?!
Title: Re: New Dyno Day at Prather Racing
Post by: 94touring on October 06, 2018, 05:15:23 AM
More photos. 

Vikram, no straight cut gears for me.  I'm calling it good as is.  You asked in my build thread about the flywheel and I think the difference was seen on the dyno during pulls.  My car was much quicker in the rev range, though the extra horsepower is probably a factor.  I let a few of the guys drive it and no one commented on clutch/flywheel difficulties. It's really easy to engage and drive.  Torque steer however...

Title: Re: New Dyno Day at Prather Racing
Post by: 94touring on October 06, 2018, 05:18:40 AM
...
Title: Re: New Dyno Day at Prather Racing
Post by: MiniDave on October 06, 2018, 06:58:52 AM
It was interesting to see the mixture ratios on the graph against the load.....that's where you really find the edge in performance. In my case mine was lean as it climbed the RPM scale, so we went with a little bit richer needle and while the overall HP only improved a bit (about 2 hp) the drivability definitely was better on the drive home - exactly where it showed me lean before. The engine just seemed to run easier on the highway.

Thanks to everyone for making the effort to come to the dyno day. All in all a great day yesterday.

Bruce and Michael Playle are driving home in the rain today - safe travels to you two!
Title: Re: New Dyno Day at Prather Racing
Post by: 94touring on October 06, 2018, 07:20:45 AM
The dyno makes it easy to spot the problems.  Well worth the money.  Also just fun having a number and graph to know is yours.  I'd like to clean up my bottom end once I find the right needles and see how much it improves the chart.
Title: Re: New Dyno Day at Prather Racing
Post by: MiniDave on October 06, 2018, 09:03:31 AM
Lets see if this will post.....

OK, a few things to note here, the power builds very smoothly, no jagged bumps, just a smooth straight line, next, the torque curve is very flat (not like you can do with FI of course) everything peaks at just about 5K rpm, as compared to Dan's chart, where the torque and HP continue to go up with the RPMs. This shows the difference in both cam profiles and cylinder head flow. The engine in my car is built for limited use, basically driving from 0 -65 mph, with the focus on mid range torque for easy drivability in town and high fuel mileage. The engine in Dan's car will do that as well, but has way more upside potential for speed....I'll be curious to see what kind of fuel mileage he gets.

Looking at the line across the bottom of the chart, it's a little bit rich at lower RPMs and a little bit lean at higher RPM, but it's all close enough for a street engine. Compare that to Dan's, he has a significant dip n the middle with a consequent dip in power and torque in the mid range. It's difficult to feel it but I'm sure with enough miles behind the wheel it will become apparent.....he's also way rich at idle and low speed where you really don't need it. The results of that are evident in the bumps in power at lower RPMs, once it gets past that point it smooths out nicely all the way to the top.

Unfortunately we didn't have any appropriate needles to change that, but some timing changes and dropping one jet and raising the other evened it out quite a bit and took the raggedness out that we saw in the early runs.

Edit by Dan: added my chart for side by side comparison.
Title: Re: New Dyno Day at Prather Racing
Post by: 94touring on October 06, 2018, 10:14:56 AM
I almost wonder if changing dash pot oil would help that dip.  Seems like it comes on strong and right at 13:1 on the target line, then catches it's breath and dips slightly rich, then right back to 13:1. 
Title: Re: New Dyno Day at Prather Racing
Post by: MiniDave on October 06, 2018, 11:09:44 AM
I would try that, it might smooth out that little bit of raggedness at the top too?

I use 20W50 in my dashpots
Title: Re: New Dyno Day at Prather Racing
Post by: 94touring on October 06, 2018, 11:15:59 AM
I know Calver says use 20w synthetic on anything modified intake or exhaust to reduce modulation in the carbs.  Atf and SU oil are best for stock.   Once the wideband gets in I'll start playing with oil to see if it calms it down.  Comparing the 2k-3k range to yours, if I can get my air fuel out of 10s and closer to 13 I should pick up a ton down there. 

Edit: ragged at the end if it's like my rotary tuning knowledge and dyno time, is ignition related, since fuel is essentially perfect there.  I was looking at that yesterday and thinking since I side gapped my plugs and gapped 30, I may need to bring them down to 25.  The side gap info says they should be gapped less than a standard plug.  So for example if you'd normally gap 35, take it down to 25.  On my rx7 you get ignition breakup when you start making big power without more spark, which I solved with an ignition amp, and flamethrower/csi dizzy on the mini.  BUT adding water and lots of it along with tons of boost begins to flood the spark and ignition brrakup comes back.  So you gap the plugs a bit tighter and it goes away.  I can't run standard rotary plugs for this reason and run a race ngk plug that I can gap. 
Title: Re: New Dyno Day at Prather Racing
Post by: BruceK on October 06, 2018, 03:07:16 PM
I just got home - about 9 hours behind the wheel today. Michael and I hit a lot rain on the first two hours, then it was overcast with damp roads the next several hours.  By the time we went through Tulsa it was clearing up, so the last 4 hours were dry.   But Michael has another 5 hours or so tomorrow before he gets home.   
Title: Re: New Dyno Day at Prather Racing
Post by: MPlayle on October 06, 2018, 04:00:27 PM
Settled into a room at a hotel in Plano for the night and have been catching up on the email backlog.

For comparison: the basically stock 998 in the Moke posted numbers of 30.91 hp and 43.34 torque.  The only recommendation for the Moke was a very slightly richer needle as the AF graph was reasonably flat at about 14 all the way across - the target being 13.

(Note: A reminder to all - everyone's numbers are "at the wheels", so the Moke was putting out about right for a stock 998 that was factory rated 40-45 hp "at the crank".)

The other side note: the Moke set the shop's new record for lowest numbers.
Title: Re: New Dyno Day at Prather Racing
Post by: MiniDave on October 06, 2018, 07:24:29 PM
Someone had to do it!   ;D

I think I was second lowest, so ......

In fact, I was so impressed with how tractable and easy to drive Dan's engine was I'm thinking of building one for my green car....of course it won't take me two years to get it built!   77.gif

How much was that cylinder head again?
Title: Re: New Dyno Day at Prather Racing
Post by: 94touring on October 06, 2018, 08:38:28 PM
Mmm after the exchange rate I want to say $1200.  Maybe that included the rockers.  I will go through receipts and let you know.

Edit: $1260 with head and rockers. 
Title: Re: New Dyno Day at Prather Racing
Post by: MiniDave on October 06, 2018, 10:25:57 PM
Plus shipping?
Title: Re: New Dyno Day at Prather Racing
Post by: 94touring on October 07, 2018, 02:01:17 AM
Shipping was extra.  No core exchange due to shipping, plus I wanted the old head.
Title: Re: New Dyno Day at Prather Racing
Post by: 94touring on October 07, 2018, 03:19:31 AM
Price guide:

1275 +40 with 10:3:1 slipper pistons. $265
Kent 266 cam    $315
KC super sport stage 3 head and 1.4 rockers   $1260
Maniflow stage 2 headers.   $110
Rc 40 twin box exhaust. $75
Maniflow twin carb fancy intake manifold  $170
Hs4 twin carbs with long ram pipes. $950
Csi 16 point electric dizzy on curve 7.  $285
Flame thrower coil  $50
Lightest verto flywheel available from MED. $145
Turbo clutch and 190mm plate vs the 180mm the kit has.  $145
------------------------
$3770


Then of course bearings, gaskets, cross pin diff, this, that... 
Title: Re: New Dyno Day at Prather Racing
Post by: MiniDave on October 07, 2018, 08:42:59 AM
plus assorted seals, bearings, pushrods, alternator and gaskets...you also bought the Vernier timing gear.... and machine work to bore, hone and deck the block, plus two dips in the tank and having the crank machined. Plus someone competent to put it all together
Title: Re: New Dyno Day at Prather Racing
Post by: BruceK on October 07, 2018, 09:05:16 AM
And Dan's engine made more power than the various MiniMania-built (and Seven-built?)  performance engines and probably ended up costing less.
Title: Re: New Dyno Day at Prather Racing
Post by: 94touring on October 07, 2018, 10:55:09 AM
I was thinking that Bruce but didn't want to say it lol.  I do have plenty of work to do in exchange for Dave's services. 

Yeah I had to stop adding up cost.  I don't want to add in suspension to the total bill.  These wheels were about 1k after it was all said and done. 
Title: Re: New Dyno Day at Prather Racing
Post by: MiniDave on October 07, 2018, 12:28:20 PM
Almost all the HP in one of these engines is found in improvements to the head.....of course you need the higher compression, cam, ignition, exhaust and carburetion to make it all work.
Title: Re: New Dyno Day at Prather Racing
Post by: 94touring on October 07, 2018, 01:35:44 PM
Quote from: MiniDave on October 07, 2018, 12:28:20 PM
Almost all the HP in one of these engines is found in improvements to the head.....of course you need the higher compression, cam, ignition, exhaust and carburetion to make it all work.

You should start advertising engines built to spec with the dyno sheet posted in the ad. 

Yep all the extra little things make the whole package.  The twin carbs were overkill since they don't provide more power per say, but should give better response and low end performance.  Ironically I'm rich there and doing the opposite of that at the moment.
Title: Re: New Dyno Day at Prather Racing
Post by: gr8kornholio on October 07, 2018, 04:35:43 PM
That's where mine would have been an interesting comparison since it is one of those god awful expensive 7 ent. 1380 motors.  Paid for by the previous owner thank goodness.
Title: Re: New Dyno Day at Prather Racing
Post by: BruceK on October 07, 2018, 07:54:33 PM
Found this site that converts horsepower at the wheel to horsepower at the crank.  Of course it's not exact, but interesting.   My car comes out at 70hp at the crank.

https://www.mk5cortinaestate.co.uk/calculator4.php
Title: Re: New Dyno Day at Prather Racing
Post by: MiniDave on October 07, 2018, 08:09:03 PM
Cool, it says my 52.5 at the wheels is 69 at the crank, more than I expected.
Title: Re: New Dyno Day at Prather Racing
Post by: 94touring on October 07, 2018, 08:24:54 PM
I hit an even 1 hundo.   

Here's a site I've used in the past as well.  Also showing about the same.  Here's a pic of the current day dyno conditions to plug into his formula.

https://robrobinette.com/Dyno_Correction_Calculator.htm
Title: Re: New Dyno Day at Prather Racing
Post by: 94touring on October 07, 2018, 08:34:20 PM
And to make it more fun.  Plug in your cars weight and hp to see times.  You will be at roughly 1400lbs according to the miniweight website.

https://robrobinette.com/et.htm

By plugging in my new estimated weight of 1150 I gain nearly 1 second in the 1/4 mile.  By working it backwards and taking my new 1/4 time and using the old weight of 1400lbs, my new equivalent horsepower at a weight of 1150 is 97 to the wheels.  So there was a method to my madness of weight reduction! 
Title: Re: New Dyno Day at Prather Racing
Post by: MPlayle on October 08, 2018, 08:12:05 AM
The site Bruce posted does not like to calculate for less than 50 hp.  I put in the Moke's 31 hp and it changes it to 50 when clicking the calculate button.

Title: Re: New Dyno Day at Prather Racing
Post by: BruceK on October 08, 2018, 08:33:22 AM
Quote from: MPlayle on October 08, 2018, 08:12:05 AM
The site Bruce posted does not like to calculate for less than 50 hp.  I put in the Moke's 31 hp and it changes it to 50 when clicking the calculate button.

You just can't get no respect!   ;D
Title: Re: New Dyno Day at Prather Racing
Post by: 94touring on October 08, 2018, 09:37:22 AM
They're like lawn mowers not welcome!  ;D
Title: Re: New Dyno Day at Prather Racing
Post by: 94touring on October 09, 2018, 04:45:58 AM
Back on the topic of tuning, I figured out what swinging needles my hs4s came with.   After much research and learning myself good on needles and curves, I plotted several out that are in the general neighborhood of what I have.  I know that these needles are divided into 16 segments.   Since I know WOT is spot on air/fuel for the majority of the dyno graph, I used the full throttle segment as a baseline, then corrected the rest of the curves to match.  For example if WOT on needle xyz is 10% more than what I currently have, I deducted 10% across the curve.  This is after seeing what each segment is in relation to my current needle.  Segment 5 may be 10% leaner, but if the full throttle segment is 10% richer, after adjustments segment 5 becomes 20% leaner.  My plan is after the wideband is installed I can see how the air fuel ratios are across 16 various throttle positions throughout the rpm range, and plot the ratios.  I am considering making a spacer with 16 increments to place under the throttle to maintain constant positions.  After I've gone through all segments and see what air fuel is per segment, I can theoretically pick a needle based on all the plotting.
Title: Re: New Dyno Day at Prather Racing
Post by: MiniDave on October 09, 2018, 08:01:08 AM
The needle position will vary not only with rpm but also load, so unless you can keep the exact same load in each position of the throttle, the needle won't stay in the same spot. Remember, when he's doing the run up, he has the throttle wide open the whole time, but the load on the car stays the same (percentage wise) as the rpms goes up - because the dyno adjusts to the input from the wheels. I don't think you can duplicate that on the street, but no question you can get it a lot closer than it is, especially since you know where to start.
Title: Re: New Dyno Day at Prather Racing
Post by: 94touring on October 09, 2018, 08:20:35 AM
I have a long straight flat road nearby that's perfect for this.  Did the same thing on the rx7, difference is I have a computer to data log to review the map the car is at under load.  So you go out and drive in various rpms and throttle position (my case vacuum to boost too) then adjust the cells accordingly to what the air/fuel gauge reads.  Tedious but you end up nats ass tuned.  There will be some variations on the road as you say, but should get in the ballpark once you start seeing trends at various loads,rpms, throttle positions.  It's even easier to imagine the fuel map of these needles when you plot them out.  I can tell where some cruise rich while others are very lean in relation.  My cruise air/fuel at normal highway speed will narrow the needle down pretty quickly I think.
Title: Re: New Dyno Day at Prather Racing
Post by: Scargo on October 09, 2018, 01:49:26 PM
Looks like a great day, guys. Nice work putting it together.

If someone would be so kind, I would like to have the contact information for the owner of the red Bugeye.

Thanks.
Title: Re: New Dyno Day at Prather Racing
Post by: MiniDave on October 09, 2018, 02:26:11 PM
PM sent....the Red Bugeye belongs to Gordon Fitch, who also owns the green 63 that went first.