P1 car engineering spitballing

[Squidink]

I recently purchased a P2 car- a Toyota WSR. Looking at the numbers, it looks slow for P2 especially in WSR trim.

I am getting my novice permit. I am an engineer with some vehicle design background.

For those that don't know, this is a steel frame car like a SRF3 with a warmed over Toyota 4A-GE with the MR2 trans and some Mr2 running gear. Cheap, not fast.

As an engineer, I am daydreaming of scoring a Toyota Atlantic engine, getting the sequential trans and then having enough grunt to push the aero to "keep up" in P1. Maybe bump the track width, too. I could even run "real" uprights and wheels.

It would still be heavy, but not a SIR restricted engine. Limited to 4 valves and 1615cc and (IIRC) 41.5mm chokes, although that could be ITB diameter(I think) and run EFI, which it already has.

This is pipe dreaming at present, and it seems the biggest thing is undertray design, which could be an issue with a transverse engine.

I am oldish, and would enjoy the engineering journey, I think. Thoughts? I could got the HELOC---> Stohr WF-1 route, but that seems less fun.

[lowside67]

Love the enthusiasm. Now for the reality check: for the price of selling your WSR, plus not buying an Atlantic motor ($10k), transaxle ($7.5k), and floor ($5k) - you could have a WF1. It will have resale, it will be quicker than what you are talking about building, the running costs will be a FRACTION of the atlantic drivetrain. And most importantly, it'll get you on track.

-Mark

[Bob L.]

Seems like rather a futile effort.... lots of work/cost, with little returns.... IF you want to get lic. stuff done, just run as is, While looking for something different to work from....many out there, may cost more now, but less over all. Have seen a few of these WSRs in vintage groups...another spot to play...but not towards SCCA lic.

Don't get too deep into that project....look for other directions...design your own if you must, but...................

edit: Better approach is to find an old Atlantic, SV, Indy light, or other single seat formula car.....roller or complete to start with/add to..........

Just my 2 cents worth.

Bob L.

[Squidink]

Maybe I am looking in the wrong places? I haven't seen a WF-1 for less than $40-45K USD?

No idea what running costs for a Toyota Atlantic engine are. But engine and trans purchase price seems about right.

I could do all this and the car could STILL be really slow in P1.

Up to a point, I could keep the existing power in the shed to convert back to a stock WSR. Maybe.

Regardless, my goal for 2022 is to fill out the P2 field. A rolling chicane for Stohr cars while I work on driving skills!

[Bob L.]

https://www.racingjunk.com/vintage/1...38&np_offset=8

[E1pix]

Deleted, see below...

[E1pix]

The biggest mistake I see over and over and over and over and over, and have for decades...

...starting with too much car, and either taking forever to get atop it, or that never happening — at least, not without lots of broken parts, lots of expense, and not much fun for the dollar from all the above.

Know it is not impossible... but the odds of real success go down with every excessive dollar spent, and with every additional candle on your birthday cake.

I’ve run well over 6,000 miles in racing karts (five state and regional titles) and know it’d be asking a ton for me to start in what you’re talking about — despite my being a bit fearless, and around racing and drivers for 59 years.

Why do people start in the faster classes? Most often it’s ego, Sorry, and that’s where injury incubates.

It’d be far better to start in a slower class and learn to drive the living balls off it — consistently, and without much incident — and then move up.

Test days in your car as is would be much more valuable compared to the “rolling chicane at a race” concept. You get more time, when you want, for as many laps as you want, and at less risk to all — and with much more benefit to your hopes and goals.

Hope you don’t mind the candor, it’s only meant well.

Whatever you do, Enjoy.

[Rick Kirchner]

The re-build on a FA toyota will cost more than your WSR roller....

Seems like a perfect platform for a bike motor conversion - but it will still be heavy.

V6 off-road truck motor......

[Mike B]

If you're looking for an engineering exercise, I would convert to a 1 liter bike engine because they're plentiful, inexpensive, powerful, and include the gearbox. It's possible that while adapting the bike engine you could clean up the rear of the chassis enough to improve the aero, at least enough to fit a decent diffuser. You'll lose some weight in the process and might start getting close to having a competitive P2.
If you're looking to mortgage your house and dip into your 401k, go with the Toyota Atlantic engine.

[10rmotor]

I was thinking more rotary power would be much cheaper than the high strung atlantic motor. Regardless of that, re-engineering that car would not yield what you're after. There are some good regional p2 cars (not stohrs) for less than 15K that are bike powered. Pick one up, go through it, and have fun! If you can't find one, hit me up I can probably find one for you!

And there has been at least one 35k stohr that recently sold.

[Fred Michael]

The biggest limiting factor is the transverse powertrain. Converting to anything else will mean a complete re-work of the back of the car. EXTREMELY expensive for what will still be an overweight car with far too much frontal area. By the time you are done it will have been far cheaper to buy that $45k Stohr and spare parts will be available for the Stohr

[tige00]

Stay away from the rotary power as the 12a parts are unavailable and the chassis is way to heavy. And the 13b will have to be an s.i.r and that my friend is junk, not to mention you will be in excess of $15,000 and no torque to push that sled. Also parts are depleting quick, no longer can get front covers we ran it for 20 years, now have abandon it for reasons stated above.

[Offcamber1]

As is. Get your license, some track time, and then when you have explored the outer limits of it, sell it and buy what you really want.

I haven't driven one, but it seems to me to be a great car to learn in.

[Dwayne Anderson]

As is. Get your license, some track time, and then when you have explored the outer limits of it, sell it and buy what you really want.

I haven't driven one, but it seems to me to be a great car to learn in.

We ran the WSR's in the IMSA pro series when there were 38 cars, and worked with the Factory. We have parts for the cars and run ours in VARA. I have worked on 10 of them in the last 6 years. I have watched many people try to make them run in CSR and P1 every thing from cutting the side frame off and the big motors Run the car as it is have fun. Having said that it will not be fast for P1. If you need any help feel free to contact us

Dwayne Anderson

[E1pix]

Squidink, in re-reading my post 7, it didn’t quite come across the way I intended.

Apologies for any offense, if taken, not at all my intention. Enjoy every minute.

[924RACR]

+1 for run it and get some seat time as-is, before deciding what to do.

Have seen too many fully-functional cars get sold then parked for years while a succession of owners modify or "restore" them then never turn a wheel, or never even complete their projects - when they had a perfectly functional car that was faster than they were, they've sunk thousands of dollars into, and have nothing to show for it.

Mind you, this is coming from a guy (also an engineer!) who built his own P2 out of an FF slider.

Take the car out, get the seat time, see firsthand what the class and the competition is all about, then decide what makes sense for you. Then you'll have a much better sense of if it's wiser to convert/upgrade what you have, or sell it and start from a better basis (at least, a lighter core vehicle!)...

Not to mention, do you have the funding to play in the deep end of P1? Or maybe you'll find yet that P2 is still crazy fast, for a good bit less money, and every bit as much of a challenge...

[Squidink]

We ran the WSR's in the IMSA pro series when there were 38 cars, and worked with the Factory. We have parts for the cars and run ours in VARA. I have worked on 10 of them in the last 6 years. I have watched many people try to make them run in CSR and P1 every thing from cutting the side frame off and the big motors Run the car as it is have fun. Having said that it will not be fast for P1. If you need any help feel free to contact us

Dwayne Anderson

Dwayne-

It's Seth.

Glad I managed to find you. I am installing the new radiator this week.

So everyone knows, this is thinking out loud. I will play in P2 now and see how it goes. This thread started because to my mind there's an opportunity for a full Toyota Atlantic engine car in P1 to take on a WF-1. At least, the power could be good. I have nothing to back that up.

The WSR is interesting to *think about* because there are easy path to upgrades: aluminum uprights and real brakes. Potentially a great engine. And a transverse sequential shift 6 speed is available from Quaife. But there's a huge challenge in underbody aero implementation. The weight is not a problem to hit because automobile engine equipped cars have to run that heavy. Whether or not they are competitive? I don't know. Again, this is thinking out loud.

All this said, I will run it this year in P2 (uncompetitively)and see if I want anything faster. I'll look at vintage racing too and do some HDPE. And inspect my bank account!

Thanks everyone for the input.

[lowside67]

Dwayne-

It's Seth.

Glad I managed to find you. I am installing the new radiator this week.

So everyone knows, this is thinking out loud. I will play in P2 now and see how it goes. This thread started because to my mind there's an opportunity for a full Toyota Atlantic engine car in P1 to take on a WF-1. At least, the power could be good. I have nothing to back that up.

The WSR is interesting to *think about* because there are easy path to upgrades: aluminum uprights and real brakes. Potentially a great engine. And a transverse sequential shift 6 speed is available from Quaife. But there's a huge challenge in underbody aero implementation. The weight is not a problem to hit because automobile engine equipped cars have to run that heavy. Whether or not they are competitive? I don't know. Again, this is thinking out loud.

All this said, I will run it this year in P2 (uncompetitively)and see if I want anything faster. I'll look at vintage racing too and do some HDPE. And inspect my bank account!

Thanks everyone for the input.

For what it's worth, if you look at the results from 2021, you will see James French (4th) is running exactly that - a Swift 014 Atlantic with sports racer bodywork. And the DP02s that are generally near the top step of the podium are basically Formula Atlantic level motor builds, on Mazda MZRs. So your idea that an Atlantic motor can be a competitive choice in P1 is certainly true, but there is no way with any amount of money thrown at it, the WSR chassis has a hope of running against the carbon tubs and brand new CFD-designed bodywork & underbodies being designed by Zebulon, literally no hope. And to be clear, those motors are $20k+ and rebuilt regularly.

If your WSR is noncompetitive in P2, dropping $30k on it will result in it being more noncompetitive in P1.

Everybody here is coming from the place of wanting to see your efforts rewarded in a competitive build that you enjoy driving. If you want to build a car, I think there is actually more opportunity to do so in P2, and certainly the goalposts are tighter.

-Mark

[patman]

I agree with all above that you should forget p1 and run in P2. I still think it will take some work to make a wsr competitive, but I don't see why it can't be done. P2 also eliminates your floor concern we require a flat bottom.

P2 is a great and (slowly) growing class. I am running a 24 year old car on a comically small budget and am still competitive even at majors/hst level. That said there are guys spending as much on a weekend in P2 as I have spent on my entire P2 program to date. So be prepared to be occasionally outclassed. Still by my observation most of the field in p1 is at that level, and I would have little hope that a budget racer could even enjoy p1 let alone be competitive.

Read the p2 rules, your car will fit right in with a bit of work and you will even be able to afford to race it!

[Squidink]

There's the problem. Per the GCR, no mods are allowed for the WSR. Which is odd. It then is like a SRF3 in P2. A spec car in a relatively open class.

If I could modify even the wheels and brakes (it has MR2 uprights and brakes and rotors) and maybe bit of bodywork it could be lighter at least and get to the class minimum. But it's close to 1300# empty.

I'll drive it. If I think it's worth it, I suppose I will plead my case to allow normal P2 suspension mods for next season.

I agree with all above that you should forget p1 and run in P2. I still think it will take some work to make a wsr competitive, but I don't see why it can't be done. P2 also eliminates your floor concern we require a flat bottom.

P2 is a great and (slowly) growing class. I am running a 24 year old car on a comically small budget and am still competitive even at majors/hst level. That said there are guys spending as much on a weekend in P2 as I have spent on my entire P2 program to date. So be prepared to be occasionally outclassed. Still by my observation most of the field in p1 is at that level, and I would have little hope that a budget racer could even enjoy p1 let alone be competitive.

Read the p2 rules, your car will fit right in with a bit of work and you will even be able to afford to race it!

[patman]

Where in the gcr do you see that?
Per the engine table no engine mods. Nothing I can see about the rest of the car....

[924RACR]

Yeah, I don't see that either - that would only be the case if it were a Spec line car, and you'd still have the option to race it either as a spec line car or under the general rules.

[Squidink]

Where in the gcr do you see that?
Per the engine table no engine mods. Nothing I can see about the rest of the car....

Ok, I am both embarrassed and very happy!

I thought the wording in the table meant NO mods to ANY part of the car! But it's the ENGINE table. (I had someone else give me this impression too, so I feel a little less dumb.)

This is a much better scenario. Now I have a chance of getting down to weight. Staring with aluminum 4 pot calipers, and then I can see about suspension from there. But if I can get 40-50 lbs out of the car, that would be great.

I already have a lithium 12v battery. If I fab an aluminum fuel cell can, that's a start. I have the lighter extinguisher option.

Thanks! As you can see, I am new to reading the GCR, and I was worried about getting a logbook and totally missed this!

[Squidink]

So. I did a little HPDE last weekend.

I HAD FUN! A LOT OF FUN!



I attended a SCCA road racing school the day prior at Thompson. I got my SCCA novice permit in a rental spec Miata. Which was the day before the HDPE, so I got familiar with the track in a slower tin top first.

Right now, I am slow and old and so is the car. Which is what I expect season 1.

The car was barely finished, and not set up. Ride heights and corner weights were off. I ran a flat bottom car with basically zero rake. Well, I am not 100% sure, but since then, I have dropped the nose. Thinking about it, I need to check with ME in the car.

The car has new electric/automatic halon, and a new fuel cell. Refuelling is not so much fun, but it looks safe buried under the main hoops, swaddled in mild steel.

At present, the car seems to be 1350 less driver. Rules state 1400 lbs minimum. Hmm.

On a chassis dyno with not so warm oil (hello, New England!) I got 125 WHP on a Dynojet. I picked up 2-3HP each run, and water temp was 160F. Engine is new. Maybe hot and broken in I can expect 135 WHP. Maybe.

PZero slicks were fine, brakes were fine, pedal like a rock, handling was neutral, communicative, no bad habits. So for a shakeout day, it was great. No DNF, ran low on gas once, drove it onto the trailer. A win for me after a long winter!

Like I said, I am slow. Partly because there is so much left in the car, even badly set up. Throughout the day, my cornering speeds just kept going up and up and up! Especially with a little aero help in medium speed corners.

I am sure there's lots left in the car. I need to set it up and learn to drive it. As much as I want to re-engineer everything, I need to just go wear out tires, brakes and me for a while- and learn how to drive.

There is a question here:

The car has no undertray/skin below the engine, and no diffuser. It is 100% a flat bottom car. Dwayne told me some setup figures, I need to look for rake and ride height. But I assume a sheet metal skin under the engine bay and small diffuser should help drag and downforce, and rake is a good thing. Right?

Also, not sure if there's a way to "read" slicks because of picking up marbles. I don't have a pyrometer yet, I do have an IR thermometer. I do have bluetooth cornerweight scales.

I still have a lot to do. The shift linkage needs adjustment before next weekend. I am dreaming of a Quaife 6 speed sequential 'box. But mostly just grinning.

[David Ferguson]

A floor under the engine and diffuser do help reduce drag, but not necessarily create downforce. Believe it or not, a large open area under the tail bodywork can create quite a bit of downforce -- measured and verified with my Swift DB-5. I did run a floor and diffuser with my Van Diemen S2 and the low tail (which made lift without a huge spoiler), but when I converted it to P2 I ran with only a floor under the engine until I eventually got the wing in the right location to work with a diffuser.

A floor under the engine is nice from an engine cleanliness standpoint. Particularly if you tend to fall off the track a few times, while finding the limit.

[iamuwere]

The biggest mistake I see over and over and over and over and over, and have for decades...

...starting with too much car, and either taking forever to get atop it, or that never happening — at least, not without lots of broken parts, lots of expense, and not much fun for the dollar from all the above.

This cannot be stressed enough. There are so many very fast cars being driven very slowly that it creates hazardous situations on track. If you aren't within a few seconds of the pole, you are in either too fast a class or too high level of an event especially if you are just beginning.

[patman]

Yes a tray under the engine will help. .040" aluminum is usually fine.

The diffuser is arguably the most important aerodynamic part on the car. Definitely build one. Make sure you read the p2 rules

Ir thermometer is fine as long as you take temps immediately after coming off the track. Not as good as a proper pyrometer, but good enough to give you an idea if your alignment and pressures are close