Quote Originally Posted by Ascinder View Post
Yes, V-8's have nice fat torque and horsepower curves while turbo 4 bangers have to rev to the moon to get their horsepower and even then their torque is lackluster. There is also the availability and expense. V-8's are produced in such high numbers and have been around so long that practically everyone knows how to work on them or can point you to someone who can. There is a huge aftermarket and knowledge base as the GM LS series has been installed into just about anything that moves. Don't get me wrong, the ecotecs are really great engines, but the VX is a pretty heavy vehicle and you're going to be running that engine pretty hard all the time, where in the same circumstances the V-8 is going to move it around in it's sleep. The ecotec is actually quite a bit lighter too, but I can't say that really adds all that much to it's value here. What's another couple hundred pounds when the vehicle already weighs over 4,000? Gas mileage is never going to be great in a vehicross. I'm sorry, but our vehicle is just not a zippy little commuter car and never will be. We weigh twice as much and take up a lot more space. I think you're mileage might be better with a 4 cyl. but if you have to rev your engine to death every time you do anything, your mileage is going to suffer substantially.
Was reading through some old threads and just came across this for the first time (I was still on my epic cross-country adventure when it was posted). Couple thoughts:

  • Ecotec Turbo 2.0 reaches max torque at 2500 RPM, max HP at 5300 RPM. I wouldn't call those "rev to the moon" figures - have you seen the chart for an RX-8 or S2000?
  • See red above. If the Ecotec makes superior HP and torque at lower RPMs (5300 vs 5400 and 2500 vs 3000) with less weight than the Isuzu 3.5 why would I be running pretty hard all the time?
  • See blue. Seems like the VX has an equal chance of being a peppy commuter as it does being a drag strip-blazing race truck, which it seems like is the point of V8 swaps that eliminate TOD.

I'm interested in improving fuel economy and reliability, not the ability to post quarter mile and 0-60 times that I'd have to be on a private drag strip to hit anyway. It seems like in the worst case I'd end up with similar performance to what I have today but with a more efficient and cheaper to maintain engine.

I might have a line on a cheap and complete Saturn Sky Redline so this isn't me being argumentative - I want to be talked out of it before I do something if there are serious flaws in the theories above.

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