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Brad Roberts
Merican V8 or Cayenne?? smile.gif



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grantsfo
Dum, stoopid and cheep Merican. Can it be done cheap? I would be all over a V8 boxster race car, but I know even 3.4 conversion cars have had running gear failures due to higher power, can you imagine what a V8 would do? Guess things could be reinforced.

But Pepper powerplant would make it legal for PCA and POC events right?
nocones
Cayenne would be WAY cool, and legal for PCA, etc...
'Merican would likely be less expensive, so more money to put into the chassis.
If the transaxle would hold (isn't that ALWAYS the question?) I think this would make for a bitchen' race car.
nocones
Also, I thought the Cayenne motor was dimensionally large?
Brad Roberts
Grant,

what are you hearing about the chassis'?? I try to stay in contact with Chris Murry, but in my stress book, he doesnt run the car enough. I'm VERY curious to hear where the chassis is weak smile.gif


The Cayenne V8 looks big with all the plastic crap, but it is no bigger than a LS1 once you get it down to just the engine.



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nocones
Okay then, next question...
What does one of these engines cost?
BeyondBad914
Problem with anything European of any sort is when you go to hot rod the thing... add "hot rod" to the equation and you will find it always = $$. American stuff can be hot rodded much cheaper cuz we are here and parts are plentiful. Guys in Germany can probably pick up all sorts of VW/Porsche hot rod parts at the local speed shop.. here you have to find it on the net, order it shipped from Germany, etc etc. or just simply overpay for it by buying it from a Porsche motorsports shop that imports it.

So I say if you are serious about trying to come up with options, I would look into three frankly. ONce you get one, the other two would be straight forward. 1. Cayenne 2. Mod Motor Ford 3. LS series Chevy Then the transaxle of course won't hold up to any real power, but should hold up to those in "stock" formats for a streeter, like a V8 w/901. Then make an adapter to run the G50 stuff inverted. covers everything else you would probably put to it. cable shifter would easily adapt as it is already there.

Do the LS Chevy first as general population would probably like that one of the 3, then add the other two.
grantsfo
QUOTE (Brad Roberts @ Oct 24 2007, 01:45 PM) *
Grant,

what are you hearing about the chassis'?? I try to stay in contact with Chris Murry, but in my stress book, he doesnt run the car enough. I'm VERY curious to hear where the chassis is weak smile.gif


The Cayenne V8 looks big with all the plastic crap, but it is no bigger than a LS1 once you get it down to just the engine.



B

I know some of the earlier 3.4 conversions on early chasis cars prior to 2000 had some running gear issues. Mostly just bearings and bushing wearing more quickly. Cant remeber specific issues that were being posted on those early conversion cars. It may have just been the skill of mechnics doing conversion as well.

Now that I think about it we have some newer conversion cars that seem to be doing just fine.
Brad Roberts
QUOTE
make an adapter to run the G50 stuff inverted.


Forget the G50. They are being sucked up for the kit car market. NOw you have Cobra's with rear mounted G50's ,which is why Mendeola is stepping up with a new mid engine tranny for the street market with multiple bellhousing choices smile.gif


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nocones
There's a G50 on Pelican right now for $2250. Wish I had the cash.

http://forums.pelicanparts.com/showthread.php?t=373850
Brad Roberts
Yep, and it appears to have sold in less than 3 hours after posting smile.gif

Too bad, I'm about 20min from it right now.




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nocones
This is why I need a stash of about $3K set aside for when stuff like this comes up.
Actually I had that not long ago when I thought I had a deal on a 930 box. Too bad that cash went to something more
responsible last month.
Britain Smith
Will the boxster 6-speed mate up with the Cayenne?

-Britain
Brad Roberts
No. I checked this out over a year ago now. Mendeola said they could make any bellhousing to fit their tranny smile.gif It wouldnt be too diffcult to have something drwan up and made to work between the Cayenne and the Boxster 6 speed.



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Brad Roberts
The DP team already has the measurements. They had to make an adapter to fit the Cayenne to the Xtrax sequential 6 speed.


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BeyondBad914
QUOTE (Brad Roberts @ Oct 24 2007, 04:55 PM) *
QUOTE
make an adapter to run the G50 stuff inverted.


Forget the G50. They are being sucked up for the kit car market. NOw you have Cobra's with rear mounted G50's ,which is why Mendeola is stepping up with a new mid engine tranny for the street market with multiple bellhousing choices smile.gif


B

No shit! That is awesome actually - I have wanted to build a muscle car with a rear mounted transaxle for years now. 'Course by the time I get to it, it will be old news and I will look like a lame follower hahaha.

Mendeola boxes are nice but $$ Hopefully they have the whole LSD thing worked out - I almost argued with them at SEMA a few years back when they told me people don't want that rolleyes.gif I would have bought a sequential box back then had they had one. They have some bogus f'd up weird LSD thing last I spoke to them. They should simply build a trans with a 930 or G50 turbo-style diff, then it has a known replaceable setup and so forth.

Before I would buy a Mendeola I would hold out for a G50/50 frankly.

Do you have any pix of Cobras with rear mounted transaxles? I saw a Cobra guy putting Corvette setups in the ones he was building (not G50s) and would love to see how they made a G50 work and where they put the clutch, etc. I would use the Corvette stuff on a Mustang fastback but don't want to lose the rear seat, so have been considering a way to use a torque tube with a G50. (way future project)
jmmotorsports
QUOTE (byndbad914 @ Oct 26 2007, 09:56 PM) *
QUOTE (Brad Roberts @ Oct 24 2007, 04:55 PM) *
QUOTE
make an adapter to run the G50 stuff inverted.


Forget the G50. They are being sucked up for the kit car market. NOw you have Cobra's with rear mounted G50's ,which is why Mendeola is stepping up with a new mid engine tranny for the street market with multiple bellhousing choices smile.gif


B

No shit! That is awesome actually - I have wanted to build a muscle car with a rear mounted transaxle for years now. 'Course by the time I get to it, it will be old news and I will look like a lame follower hahaha.

Mendeola boxes are nice but $$ Hopefully they have the whole LSD thing worked out - I almost argued with them at SEMA a few years back when they told me people don't want that rolleyes.gif I would have bought a sequential box back then had they had one. They have some bogus f'd up weird LSD thing last I spoke to them. They should simply build a trans with a 930 or G50 turbo-style diff, then it has a known replaceable setup and so forth.

Before I would buy a Mendeola I would hold out for a G50/50 frankly.

Do you have any pix of Cobras with rear mounted transaxles? I saw a Cobra guy putting Corvette setups in the ones he was building (not G50s) and would love to see how they made a G50 work and where they put the clutch, etc. I would use the Corvette stuff on a Mustang fastback but don't want to lose the rear seat, so have been considering a way to use a torque tube with a G50. (way future project)



What about a 928 transaxel? It would be a fairly easy setup in a Mustang and all adapters are avalible from KEP or Renegane.

Jerry
nine14cats
SBC...all the way....

I had a 350 SBC built for JLO with 380HP, roller rockers, the works....less than $5K...

Bill P.
BeyondBad914
QUOTE (jmmotorsports @ Oct 27 2007, 04:35 AM) *
What about a 928 transaxel? It would be a fairly easy setup in a Mustang and all adapters are avalible from KEP or Renegane.

Jerry

My understanding is they can't take a lot of power either. At least that is what I have heard (no personal experience with them). When I first saw the way those cars were set up, I thought it was awesome. Then in the 90s when the Vette went to the rear transaxle, I just knew I had to do something with my 70 Mustang Fastback.

Then I realized being a mechanic is back-breaking work, sold the Mustang to pay for college, had driven a friend's Pantera... so here I am with a V8 914 and an engineering degree cool_shades.gif Best investment ever made with that mustang was selling it for school hahaha.

Anyway, the Mustang I would want to build would be a 440cube SBF with most likely a screwcharger (tho' maybe turbos) and most of your kit car guys build big power too, so a weak Porsche rear trans won't work in those situations.
ajracer
Got my Vote !!

That was easy since I already have a 914 V8 with a five speed Boxster tranny
and have been driving it for about two years now. Including mainly street but
some track event here in Ontario. But maybe looking for a top end over 130MPH
thus considering optional final drive ratios; which I understand maybe a challenge
since no one race Boxster of offered aftermarket gears. Seems of recent someone
mentioned German Transaxle fo America was working on some mid-engine tranny
for the kit car market, but will need to contact them and obtain some info or progress
on the project to see if optional gears are actually available. Happy Motoring !

Allan
Toronto, ON Canada
Brad Roberts
Hi Allan,

How did you handle the starter? Did you use a GM starter on the block and cut the bellhousing? Any pics?



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nocones
What he said!
I'd love to see photos, and hear about the details of installation.
ajracer
Gentlemen:

The starter issue was one of the main challenges but I quickly realized there were a few
ways to address my concern and find a solution. NO we didn't use a GM starter, however
we used the stock GM starter location with a custom starter mount (which set the drive
gear about two inches closer and stock GM).

The actual start is a gear reduction unit that was provided by the starter company, and not
one that he released the actual details to me. But from my understanding it is similar to the
GM reduction starter other than it has a different drive gear to engage the ring gear. Also
I believe it was a Porsche 9 tooth / pitch drive gear.

In regards to the bellhousing, it was only very slightly modified in order to make way for
the starter drive gear clearance issues, and a removal of a casing tab which interfered with
one of the engine mounting bolts.

Some photos are attached and or will follow, but the real challenges were with the custom
components and work that is not seen. Below is a littl eintro I provide elsewhere to some
others that had also inquired regarding my Boxster V8 conversion. Happy Motoring !

A BIG QUESTION for many is more than just Tranny Prices vs Conversion costs !!
you can quite easily pick-up a used Boxster tranny (5 spd.) for about $ 1,500 - $ 2,000.
BUT you need to know the following items are necessary for the conversion in addition to
the actual tranny costs:

- two minor modifications to the tranny casing, non structure mods.
- hydraulic Clutch pedal assembly conversion.
- conversion of axles/hubs/brakes to the Porsche 5 bolt.
- Porsche 5 bolt axle assemblies and special length axles.
- Custom made adapter plate
- Custom built flywheel (for your particular engine)
- Custom Pilot Bushing/Bearing Spacer
- Special Porsche Starter Ring Gear
- Custom Clutch Assembly, Kelvar Disc.
- Custom Starter & Mounting Bracket.

No of the above items are commercially available, but would need to be designed, engineered and then custom built for you. This project was a project car for me and not
a business for me, however I did make templates of all the components mentioned above (except the hydraulic clutch conversion & 5 Bolt axles) and retained all my engineering drawings in order to re-duplicate the process or to sell to others if and when the need might arise. In my personal opinion to do this conversion it would cost over $ 5,000 for all the pieces including the tranny to complete the project. This would also depend upon your abilities as to what you can do yourself and what you would have to pay others to do. So you can see it is still a costly undertaking, BUT one sweet tranny, shifter and well working unit !


Allan
Toronto, Canada
Brad Roberts
Allan,

You did a great job!

I would like to talk to you about the adapter/clutch setup smile.gif


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ajracer
Brad:

I would welcome your inquiry and discussion; I think we can all learn from others
and usually find a workable solution to the challenges. Please drop me an email and
or PM with contact info and we can talk.

Allan Mayhew
Toronto, On CDN
Brad Roberts
Thanks Allan.



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Brad Roberts
Not sure how this came back up.. lol.gif somebody must have voted in the poll confused24.gif



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BKLA
What about a Fortin Transaxle? Will they support that HP?
Brad Roberts
No problem, but they are nearly double what he has into this smile.gif


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Brett W
The Boxster Gear box was rated by Getrag at 380nm of torque. Thats is about 280 ft lbs. Not much better than the 901, but at least you could use first gear without breaking it off. Here are the specs.

http://www.getrag.de/en/241
914 Engine Surgeon
we have teamed up with the guys at Beck to put Boxster engines/ trannys into 550 replicas. The first one is underway now. I am building one into a test bed for our engine development because making changes to it will be a breeze...

I ok buy your old engine cores if you swap to a V8.
andys
ajracer,

If you are adapting a GEN I SBC to the 5 speed Boxster (nee Audi model 012), there may perhaps be an easier way to go about if my information is sound (?). According to the guys on the GT40 forum, the SBC to Audi (model 016 5 speed) Kennedy Eng. adapter plate will also work on the Boxster/Audi trans (5 speed). So too will their flywheel, clutch, and starter. If this is in fact the case, then it would save a great deal of work. I do know that the Boxster/Audi trans input shaft is recessed past the bellhousing surface, where as the model 016 Audi trans input shaft proturdes slightly ahead. This would of course require some changes to make up the difference.

On my GEN III (LS1) to Audi 6 speed I had to make up quite a few of custom parts to get it to work. The GEN III motor has some major differences over the GEN I SBC.

With regard to the Boxster conversion, it would seem to me that utilizing the modern Chevy GEN III (or even GEN IV) light weight aluminum V8 which has a really good EFI would be a better choice than the old school GEN I motor. IMHO.

Andys
Andyrew
Why not the 4.2 Audi v8?
andys
Andyrew,

The Audi V8 is big by comparison, overhead cams and towers, cam drive, etc. The GEN III Chevy OHV is pretty compact and makes very good power out of the box. Electronics (as you know) is another issue to deal with. I don't know anything about the Audi (stand alone, intergrated, etc), but with the GEN III Chevy there are several vendors that modify/make custom/re-program harnesses and PCM's, so no surprises there. The Audi would of course bolt right up (but you'll need Euro parts, as A8 V8's were never imported into the US with manual transmissions.

Andys
Brad Roberts
Lost but not forgotten!

Should have some Audi engineering questions answered tomorrow smile.gif

I asked if the Audi V8 had the same bellhousing bolt pattern as the V6 S4 twin turbo smile.gif



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Andyrew
I believe so, They have the same trani I believe, but I've never pulled them so.. We'll see! If they did that means that its the same housing as the 1.8t and the 2.8 engine.
Brad Roberts
I know the 1.8T has the same bellhousing clap56.gif

Andrew,

do you think you can locate me a Jetta or Gulf TDI engine+ tranny? Or the Audi TDI?



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davidginsberg
I looked into getting the 4.2 engine to use with my 1.8t/boxster trans swap. It is the same bolt pattern. And the s4 4.2 is a REALLY small v8. They shortened the whole engine allot by placing the timing belts on the rear of the engine.
Brad Roberts
QUOTE
It is the same bolt pattern



SCORE!!!


Getting the itch to convert something.. with something cool smile.gif



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Andyrew
QUOTE
I know the 1.8T has the same bellhousing clap56.gif

Andrew,

do you think you can locate me a Jetta or Gulf TDI engine+ tranny? Or the Audi TDI?



B


Ohh thats a hard one. I dont see them at all on the forums I am regular to.. Lemme check some others.
grantsfo
I'd be willing to do something like this if it isnt crazy expensive.
Brad Roberts
I'm trying to locate an engine right now.



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r_towle
to convert something cool with something cool..

GRM magazine did a short article about a VW Beetle TDI pushing over 400 ft lbs of torque...

Stuff that into a boxster and run it on grease....

Rich
grantsfo
QUOTE
to convert something cool with something cool..

GRM magazine did a short article about a VW Beetle TDI pushing over 400 ft lbs of torque...

Stuff that into a boxster and run it on grease....

Rich

Ack! That would be nasty. I'll take a humble Porsche V8 or even a 3.8 6 please.
Brad Roberts
Keep that thought RichT smile.gif How about the TDI in a 914 instead? 70+ MPG and a reliable 300hp smile.gif



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Britain Smith
I will take a TDI powered 914...make it run on Bio...

-Britain
r_towle
QUOTE
Keep that thought RichT smile.gif How about the TDI in a 914 instead? 70+ MPG and a reliable 300hp smile.gif



B


Keeps coming back like a bad cold. lol.gif

Passat tranny fits and bolts to the motor...
TDIClub.com has a guy who is doing one...
BTDT, did the research...

Just keep thinking about it...that is why I found that beetle that puts out 400 ft lbs of torque...

In the next month or so I am going to get a beetle TDI so I can learn about the motor...see if its all they say it is.

Personally, I would rather do it to a boxster...they are worth less lol.gif
Plus they already have radiators.
Just not sure if all of it would fit...
I bet I could find a boxster for less than 5k with a blown motor....hmmm

Rich
grantsfo
QUOTE
QUOTE
Keep that thought RichT smile.gif How about the TDI in a 914 instead? 70+ MPG and a reliable 300hp smile.gif



B


Personally, I would rather do it to a boxster...they are worth less lol.gif
Plus they already have radiators.
Just not sure if all of it would fit...
I bet I could find a boxster for less than 5k with a blown motor....hmmm

Rich


LOL! Aint that the truth!
grantsfo
QUOTE
Rich, a lady with an early Boxster that recently suffered a broken IMS, just sold the complete roller for $3K.

that would have been a perfect candidate for some research and bastard transplant.... happy11.gif

TDI in an older Boxster platform would be interesting, and like you said, all the plumbing/radiators are already there.
much easier than trying to do it in a 914.

The blue one? That had a hardtop? That was a screaming deal! The hard top alone could fetch a grand.
r_towle
Thats the kinda price I like too.
I would have sold you the hardtop and the wheels...lol.gif

Rich
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