Todd M posted:edsnova posted:
4. Yes, Subie transaxles can be used in a Speedster (if you flip the R&P which is spendy and tricky) but also you'll be modding the guts of the car a lil to make it all fit.
5. The fetish for a 5 (or more) speed is very strong for some reason and it's really quite silly, on a dollar-per-grins basis, unless you're the type who just has to run 10/10ths all the time & so are equipped with a high-strung engine with a little teeny tiny powerband way up the der stratosphere. Basically any good street engine (and especially any Subie) will be "on cam" at least from 3500 to 6000 and it really isn't hard or expensive to build a VW box that will handle the torque you're making, land that engine in its sweet spot between gears, be able to hold a hill at the stop light and cruise at 70mph+ without deafening you. With a Subie 5 speed you're adding weight and complexity galore and spending cubic dineros to do it & in the end, yeah, sure, it really is "better" but you better really really want it.
I got curious and looked up the transaxle weight; 89 lbs. for the VW and 150 lbs. for the Subaru. 60 lbs. for more gear? I would say, "Heck Ya!" But the cost? Low mileage Subaru 5 speed 2 WD used; $1300 not including the reverse ring and pinion, SubaruGears rebuilt $4,000 including the reverse ring and pinion. The reverse ring and pinion cost a grand if you wanna install them yourself. VW 4 speed rebuilt by Rancho Transmission; $775. On the plus side, the 5 speed is a straight bolt on to a Subaru match engine, so you save on the adapter plate. Also, I am fairly sure that the Subaru ECU is expecting sensor info from the transaxle, so the Subaru 5 speed would be a cleaner install. Is it worth it?
I saw a wide body at Vintage the other day that had the Subaru 5 speed. The body mod was not extensive, and it was handled well, so well that the modification looked like it belonged there. My guess is that the body mod for a 6 speed would be about 4 inches longer and from what I could tell, it would not be a problem, but according to SubaruGears, they don't make a reverse ring and pinion for a 6 speed Subaru.
No way a stock or built IRS VW Bug trans weighs 89 pounds. Mine was maybe 65-70. A Swing axle with the axles and hubs attached might be 90.
You get it built with stock late-model Bug gear ratios and a 3.44 R&P, with the heavy duty side cover, Super Diff and a few other hop-up details. They call it a "Pro Street" build and it's good for 180-200 horses, which is what you'll get with a NA Subaru. If you're not doing competitive hill climbs or drag racing every weekend it'll hold up just fine. The box should cost $1,100—certainly no more than $1,600—all done and waranteed.
It's way less money than trying to get a Subaru setup in there.
With a 25.4-inch diameter tire/wheel combo, these ratios put you at 60 mph in second gear, 100 mph in third and up to 140 in fourth at 6000 rpm. At 70 mph you're turning 3000 rpm, which isn't much more than final drive in most modern 4 cylinder cars (my wife's 2010 Corolla spins 2800 at 70, for example).
In a car like the Speedster, which is barely half what a modern Subaru weighs, you're never in the wrong gear even with even the weakest stock EJ22. 20 mph in 4th? Yeah, so? You wanna go faster up this hill but don't wanna put down your latte and shift? Just press down on the gas pedal. It's almost boring.
The adaptor kit from KEP is $500-ish. It works, and there's no issue with the ECM not getting the signal from the trans—although the stock ECM does want to see a vehicle speed sensor signal, so you end up having to make one of those if you're using a Subaru computer.
The bad news with the KEP is you get a heavy flywheel. Not good for racing but if you're racing then you're not building it this way anyway.
Again: A 5-speed is absolutely better, from the point of view of coolness and bragging rights and gear choices and less rpm drop between gears and whatnot. But there is no scenario in which one is necessary, especially with an NA Subaru engine with its wide, flat torque plateau from like 2500 through 5500 rpm.
If your engine makes 125 ft-lbs torque at 3000 and 126 at 4000 and 124.5 at 5000 (which it does*), then gearing up to hit 4000 instead of 3600 rpm in your 3rd to 4th upshift saves you exactly nothing in terms of acceleration.
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