Boxster Subaru conversion interest?

[kabel]

great progress, thanks for continuing to keep us updated

[Pat]

God I love this thread

[RandallNeighbour]

the motor sounds great too!

That track looks fast. Much faster than the one I drive on here in Texas. Lots of long sweepers.

[sgt brad]

ah...the sound of a blow off valve in the morning

Amazing work! That has to be a very powerful toy!

Few question:

1/ how do you like the MR2 electric power steering ?
2/ What transmission year model do you have ?
3/ Did you figure how to hook the ABS ?
4/ does the CV axle not the same length right and left because of the R&P on the side?

Thanks

Greg

[kcpaz]

Originally Posted by Boxeer

Amazing work! That has to be a very powerful toy!

Few question:

1/ how do you like the MR2 electric power steering ?
2/ What transmission year model do you have ?
3/ Did you figure how to hook the ABS ?
4/ does the CV axle not the same length right and left because of the R&P on the side?

Thanks

Greg

The MR2 pump works perfectly. It's a variable speed unit based on load. It feels completely natural.

The transmission in the test car is a stock G86/20 which is the stock 6 speed in the 2000 Boxster S. The adapter kit will work with all Boxster/Cayman transaxles up through 2008.

The ABS system functions exactly as is would in a stock car. Nothing had to be done to the stock ABS system to make it work with the engine conversion because the ABS system doesn't take any input from the engine management.

Porsche transaxles all use equal length axles... unlike BMW stuff.

Glad to know you have the PS working with variable speed! I only heard people using it ON or OFF which is really bad for the pump to run 100% all the time.

When I look at the 2005 Boxster S engine on the floor. I have a hard time to imagine the axle the same length...
The only way it could be possible is if the engine is offset on the right a little bit. Or maybe It's a very good illusion. I just measured with approximation 6.5" in from input shaft of gearbox to left CV flange and only 5" from the same axis to the right CV flange.

Thanks

Greg

[vijen6]

Dang .. just went through the entire 12 pages .. my car feel so inadequate now .. *bow down*

[Mike_Yi]

Damn cool man!

I'm curious though about the scoop. Is there not enough positive air pressure at the rear deck lid for a scoop there? It would be 100x cooler without the scoop. What about side scoops of some sort through the fenders ala Countach?

[kcpaz]

Originally Posted by Mike_Yi

Damn cool man!

I'm curious though about the scoop. Is there not enough positive air pressure at the rear deck lid for a scoop there? It would be 100x cooler without the scoop. What about side scoops of some sort through the fenders ala Countach?

The next step on that front is to install some temp probes before and after the intercooler and log the air charge temps under different conditions and set-ups.

The side ducts are being used for oil coolers for the engine and trans.

[The Radium King]

i wonder if anyone has ever tied an electronic boost controller into a steering wheel position sensor - less boost when turning, more boost in the straights ...

[Overdrive]

Originally Posted by The Radium King

i wonder if anyone has ever tied an electronic boost controller into a steering wheel position sensor - less boost when turning, more boost in the straights ...

But what happens if you happen to have the wheel in a neutral position in the middle of a turn/slide (not likely, but could happen)? Full boost when you don't necessarily want it. Or on the flip-side, your boost gets cut when you cut the wheel to move from behind someone to make a pass.

I definitely get where you're going with the idea and see potential with it, but that was where I could see trouble with such a thing.

[The Radium King]

ok, how about interfacing it with a lateral-g sensor? reduced boost when the car is pushing sideways ...

[Topless]

Originally Posted by The Radium King

ok, how about interfacing it with a lateral-g sensor? reduced boost when the car is pushing sideways ...

I don't know. This might result in the same thing as a "lift throttle" mid corner, inducing a spin. The basic rule with a 930 or 951 is: When the car comes on boost, make sure your steering wheel is pointed straight... even if you are mid-corner make sure the wheel is pointed straight.

If it was my car being built, I would favor a wider, fatter powerband and give up some top end HP in favor of drivability. A 997TT is really pretty good here and any turbo motor could be tuned for drivability. Everything is a tradeoff.

[kcpaz]

Originally Posted by Topless

I don't know. This might result in the same thing as a "lift throttle" mid corner, inducing a spin. The basic rule with a 930 or 951 is: When the car comes on boost, make sure your steering wheel is pointed straight... even if you are mid-corner make sure the wheel is pointed straight.

If it was my car being built, I would favor a wider, fatter powerband and give up some top end HP in favor of drivability. A 997TT is really pretty good here and any turbo motor could be tuned for drivability. Everything is a tradeoff.

I am seriously toying with the idea of building a turbo capable Subaru EG33 (3.3 liter flat six cylinder) and swap it in using the same turbo as what's in there now. More torque, more linear power, and faster spool. The down side is the engine is heavier and longer and parts aren't as readily available.

[kabel]

Originally Posted by The Radium King

i wonder if anyone has ever tied an electronic boost controller into a steering wheel position sensor - less boost when turning, more boost in the straights ...

Yep. My 2011 Mazdaspeed 3 has that and I have to say it is pretty annoying and wish I could disable it for track days (technically you can but it also disables the electric steering assist).

[kcpaz]

Quick update...

Based on the over cooling we experienced during testing, we decided to try out a new intercooler set-up. Without adding any serious complexity, or reconfiguring the front of the car, we were able to add an air to water intercooler system and get rid of the roof scoop. We will be utilizing the center radiator from the engine cooling system as a heat exchanger rather than using it for engine cooling, then just replace the air to air intercooler with a new intercooler, plumb a few water lines and add an electric pump. Basically the same components we will be using in the street cars, but with a slightly larger intercooler core. We will be testing the new set-up this weekend, but already, the benefits are a reduction in weight (up high and out back), reduction in aerodynamic drag, lower center of gravity, and better rearward visibility. We just got back from some dyno tuning and the car made 430whp and 380ft/lbs. The car now weighs 2651lbs with a half tank of fuel and an empty cool shirt cooler. There's another 20lbs that will be coming out over the coming weeks. Leakdown numbers are still right around 10% (cold) which is what they've been since the first test day.

[E3EJvilla]

Awesome!! Please keep updating this thread!

[kcpaz]

Well I've decided to change things up a bit. The Subaru conversion has proven to be 100% reliable in race application, so this prototype drivetrain is going to be transplanted into a street car for further testing in a more practical application. The street car will have A/C, non-electric power steering, and all of the creature compforts of a daily driver.

The race car on the other hand... it will still get an engine conversion, but something a little different. I'm actually going to pull back on the horsepower a bit and drop down a class to mix it up with some new cars. I'm going for linear power and hopefully keep the weight the same, if not slightly less. We'll see...





Yes, I realize that this has been done before, but this one will be a little different.

[insite]

Sweet; can't wait to see the build