StangJonGT
Founding Member
Generally speaking, stock turbo cars run very small turbos and achieve incredible torque and hp at low rpms, but will fall short of breath (and hp) just like a stock Mustang does--not enough airflow at higher engine speeds

Zero Signal said:That's true, but I think it's due more to the fact that the turbo is spinning so fast that it's way outside of it's efficiency range, so it's flowing air, but it's taking alot to turn it as well.
As for the lag, I don't know that that's an issue with current technology and proper turbo sizing. I've heard that alot of TT Supra guys are actually going single.
StangJonGT said:How can you say that? It all depends on turbo size. If you want a turbo that will make any kind of appreciable gains, there will be associated turbo lag, due to the larger turbine needing time (and exhaust) to spool up. That is precisely the reason for a twin turbo setup--two smaller turbos = less lag and more power. As for your smaller turbo holding boost levels across the rpm range, that too is incorrect. Generally speaking, stock turbo cars run very small turbos and achieve incredible torque and hp at low rpms, but will fall short of breath (and hp) just like a stock Mustang does--not enough airflow at higher engine speeds. Blowers will make boost the higher you rev them, if it is a Centrifugal blower, not limited by displacement of blower.
Jon

yellow1995Cobra said:An SC61 turbo, will see full boost by 2700 RPM's on an h/c 302, and maintain its power across the rpms. It supports up to 680 hp (flywheel).
If you pick the right turbo, u will have no lag(well hardly any) and have boost very low in the Rpm's. I see no reason to go twin turbo on a 302, unless your going for well over 1k hp and want some streetability.
Yes a centitrigual will make more power the higher you rev it, but they all have there limits. Your pushing your luck if your running 20#'s outa S trim. A turbo is far superior to a centrifugal without a doubt. Mainly for the area under the curve, and hardly any parasitic loss.
StangJonGT said:I completely agree with turbos being more efficient than supers. I never said they weren't--I simply said the centrifugals are very similiar to turbos--in fact, they are affectionately called belt driven turbos. Again, I will stress that a well matched turbo will give great results, hiding many of the turbo problems (lag, heat)--it just takes alot of research to get the right turbo for you application. I think everybody here is saying the same thing, just saying it a different way.
Jon
TMC said:I don't really think we are saying the same thing in different ways. yellow1995cobra is pointing out, much like I tried to, that turbos make full boost low in the RPM range and hold that boost. Vortech, Paxton and Procharger style blower don't do that. They make more boost as a function of engine RPM which is very different than the way turbos operate.