Time for a new project - A $2010 GRM Challenge Car

[jpnovak]

Don't worry there is Porsche Content here. Probably more than some of the other "technical" posts that we see.

Introducing my new project. "Dirty Penny"

Penny is a 1975 Porsche 914. She has been sitting unattended for a while. I found her at a friends house under the old oak tree. Penny is wearing copper metallic paint and had a white interior. Penny arrived without a heart. I am going to give her new life.

Penny will be built as a Grassroots Motorsports $2010 Challenge car. For those not familiar that means you have $2010 to build a car where it competes in a concours, drag race and autocross. The prize? Notoriety in GRM and ridicule from those who already think you are nuts and cheap. My wife doesn't affectionately call me Fred Sanford for nothing.

Here are a few pictures of Penny being unearthed from her previous home. The TX sun has not been kind to the paint, nor the interior. However, the dry climate has left her remarkably rust free. There is rust in the Hell Hole that has been previously cut out yet never welded back in. Rot is almost non-existent.







How much money I have left to spend on the project.



The plan is simple to do well at the Challenge. Get a car that handles well. Strip the weight out of it. give it some extra HP. Let's see... A 914 handles well. they are already pretty light. but the Type IV doesn't lend itself to high HP without major $$$.

A bit of late night ebay browsing and I came across a JDM Subaru EJ20G drivetrain. Yes, that's what I need. ITs still a flat-4 - yet has to be water cooled and makes 140+ HP/L in stock trim. I like it. The vendor was in Dallas which means reduced shipping costs. Yep, that's the rule. you must account for ALL purchases.

The new heart and soul... Oh yeah it will have soul!



to be honest, work has been crazy and I have 13 months to build the car. Progress won't be fast. I am excited to make this go forward. The challenge of swapping the entire drivetrain begins with connections. The engine mounts are easy. Trying to get the shift linkage, clutch linkage and throttle cable done on the cheap is not so easy. (I have a secret, I have most of this already figured out, I just need time to execute).

Bring it on!

Until the next update...

[Scooter]

Please strip those ridiculous rubber bumpers off!

[jpnovak]

Gladly Scott. Just find me some cheap replacements. Free is even better. And yes, I can lay fiberglass if anyone wants to donate parts.

[TWIN911]

Good Project, the good news is your not the first to do this. Hope this helps.

http://www.renegadehybrids.com/914/Subie/Subie.html

[boba]

This will be fun to follow.

[McLovin]

Cool! But you can really get that done for under $2010???

What are you at now, for just the car and engine/trans?

[9dreizig]

subscribing,,

[chocolatelab]

i saw an article about this grm deal.

looks like an absolute blast!

Good luck.

[911st]

Might be better to find a car with the motor you want and junk it for cash with the goal of a free motor or making money. Plus that way you will have all the little pices to make it run.

[richemj]

Throw Marty's turbo on it! That was a freebie, right? Scrounch muffler shops for piping extras on the cheap or free. A couple of hours behind a TIG/torch and there is your plumbing. No muffler of course!

Also, I'm organizing a PCA-LSR hosted swap meet at Porsche of North Houston on 10/31. A great place to get parts. Explain your project (better yet, tow it out in current build form) and you can probably score some freebees too. Hope you can make it. Pass the word to the greater-Austin crowd.

Pcar Swap Meet - 10/31 - Porsche of North Houston

More info to come out soon.

[jpnovak]

wow, more interest than I thought. I agree, others have gone down this path. However, when you look at the cost of the Renegade kit this seems ridiculous.

Yes, I am confident that I can build the car for the allowed budget. It will be extremely tight given the cost of the drivetrain. yes, it eats up close to 3/4 of the budget. The local pic-n-pull will be my new weekend hangout.

The car is totally complete. It came with all the parts except for the engine and tranny that were removed long ago. There is nothing else on this car that will be needed to make it run. All of the little pieces that are missing will not be used for the Suby conversion.

The price was low enough that I can essentially make it "free" within the rules after selling off some parts. There are a few things that are worth enough money to recoup the investment. Full dislosure on costs will be made if the project succeeds. If I cannot complete for the allotted budget then it will be fully developed into a full track car. That is the eventual goal for the car anyway.

The Suby clutch will be converted from hydraulic to cable operated. I do not have budget for new pedals and master/slave cylinders.

The Suby transaxle will be cable shift with custom mounts. It will have a welded differential and a welded center differential to convert AWD to 2WD.

The Suby motor will run the stock JDM ECU.

The radiator will likely be sourced from an early VW application (golf/jettta). Yes, Penny will live on water cooled.

I will custom fabricate the motor and transmission mounts. Initial CAD drawings are nearly complete.

The trunk will have a minimum cutout near the passenger shock tower to clear the turbo. the intake and intercooler will likely be flipped around. Although, I am tempted to cut out the entire rear trunk and tube the whole rear end. To really make this work I need a full cage tie-in but I don't think I have the budget for the steel.

Overall, its surprisingly simple to plan this conversion. There have not been too many technical hurdles.

Now, if anyone has any free scrub tires in a 205-50-15 I am interested. They must not be corded. Heat cycles are OK. I don't trust the existing rubber due to age.

[jpnovak]

Mike, Sounds like a plan. Are you going to the Zim's swap meet next week (10-2/3)?

Yes, I will be a parts scrounge - and proud of it.

Yeah, I will be fabricating my own open exhaust.

I forgot to say... I plan to drive the car from Austin to Gainsville, FL for the Challenge! Probably with ear plugs.

[silverc4s]

Jamie,
Very cool project, as always.. I may have some stuff laying about that can help you. Let's get together & discuss on the next outing...

[MichiganMat]

Love it.

The GRM Challenge was tempting, but we're running Lemons instead.

[richemj]

I have 2x 205/50 R15 Potenza S03 that I am looking to switch out pretty soon. About 1/2 - 3/4 tread left. Getting a little too hard for a street car. You can have them when I buy new, probably in a month or two.

[copbait73]

Jamie:
Sounds like a great project and so far your logic for selection of make/model and driveline are spot on. You will have many unforeseen challenges as it progresses so don't change a thing that doesn't require change. It's the details that gobble up time and motivation.

I studied this motor vs Type IV for aircraft use. Run a guesstimate on your weight and balance. Water cooling can be serious weight if you run it forward but that may not be required. Put it in the rear shelf with a fan and keep the cooling system piping, fluid and heat exchanger installed weight down.

Keep the turbo as is but add water methanol injection and serious boost.

Finally, don't spend too much time talking to us....just build. The Richeys are pulling for you!

[jpnovak]

Marty, I am ahead of you on the radiator placement. I have been studying this page for alternative locations. Its all about airflow.

http://www.cassidy-online.com/porsche914/aerodynamic_aids/index.html

Let me get the car running and driving before cranking up the boost. yes, it can be run quite high for serious output.

My sources say that the entire package including the radiator and contents is not much heavier than the TypeIV. I think the actual longblock is a bit lighter than a typeIV. I don't know for sure. My donor didn't come with a motor for comparison.

thanks for the encouragement.

[jaybird840]

Oh HELL yeah!!!

[David S. Wallens]

Yep, very cool.

[jpnovak]

I guess that is the unofficial GRM stamp of approval - Thanks David

Since this thread was brought back to life I thought I might as well post an update.

I mocked up the engine mount in CAD. The package all fits together within the measured dimensions of the engine bay. Here is the model engine mount. There are two vertical struts that will bolt to the rear shock tower cross member. Two engine mounts connect to the flat four. The Suby engine has engine mounts on the backside next to the bell housing connection. These are angled at 22 deg per side. Two forward extending struts will connect to the stock engine mount locations. This effectively ties the rear of the car together. Triangulated bracing is not shown for simplicity. The design also clears the up and down pipe on the turbo.



Enough with the design. Let's start cutting metal. I started by supporting the car on jack stands. Then I cut out all the mounting channels for the air seal. This car will never need these again.



The next step is to cut an opening in the rear tray/cross member for a little chassis reinforcement. It is well known that high g-loads can cause separation of the shock towers from the longitudinals. The problem lies in the fact that the rear shock towers are not actually welded to the ends of the longitudinals. One side of the cross member mounts to the shocktower and the front side of the cross member mounts to the longitudinal. cutting an opening followed by some welding can easily solve the problem.



Once the access hole is opened, I simply seam welded the two sections.



I also welded up the top section to further connect the shock tower to the longitudinal.



Next, I fabricate the reinforcement sections for the corners. These will serve as the mounting points for the engine yoke/cradle. These are simply cut from scrap 3/16" flat stock. good thing scrap steel can be had for free if you know where to look.




Here are the two corner sections installed. I also drilled and tapped holes and then welded nuts on the backsides. These blind nuts will serve as the upper mounting holes for the engine yoke. Two bolts on each side of the vertical struts pictured above.