Ever Banged Your Head Against A Brick Wall?

HighLift said:

I think I missed a lecture between Tuning 101 and that thread.

Is the argument that throttle response is subjective? Throttle response is relative to your expectations? OP says his turbo has better TR than his NA, and others say "yeah but.."

Any chance of a summary for the eager (but feeling retarded) peanut gallery?

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There are many counter debates for all methods of intake, some plausible. You cannot attain huge power gains without some degree of sacrifice. OEM drivability is everyones goal, some are saying you can have it some say not. Lets face it ...put your foot to the floor in an fi'd mx5 in any gear will scare many people sh*tless (is that OEM drivability any more than the shift in G when you come of the throttle hard) There are many workarounds for many of the challenges associated with FI of which many are explained. Anybody who has gone through the tuning process will be familiar with at least a number if not all off them.

There is a rotational mass and pressure drop associated with both turbos and in a slightly different way superchargers. You could argue that a supercharger could provide sufficient air movement at idle for there to be no latency on throttle application, but equally say that the additional mass has also to be accelerated creating more latency. A turbo could be said to have increased pressure drop and not apply any additional load on the engine upon instantaneous throttle application, yet pressure drops "initially" would be higher. The other variable that can be added is the volume and associated mass that needs to be moved (in an ideal world instantaneously). This is one area where IRTBS really do shine given that the mass has minimal volume associated with it, it is much easier for it to gather momentum.

You may have read about the heal and toe to maintain rpm levels (Turbo's) but many rally tuners have deployed direct fuel injection to keep the turbo spinning (hence the flames) to keep the efficiency (more importantly reduce the latency on spool up) near peak.

Its down to what works for you and what doesn't. When limits are stretched to high power levels from a small displacement, nobody can have it all. Yet in most cases there are workarounds, but these exponentially increase the costs.

It covers nothing more than the supercharger vs turbo threads that keep prevailing here.

My slant any way...

Sadly I enjoy reading stuff like this.....top find..

HighLift said:

Same road same time same speed, both give it beans, who is ahead after 1/2 a second. That's throttle response surely?

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erm....not wanting to fan the flames, but surely that's preciely not what's being debated? or at least how i read it.

2 cars, you plant the throttle, which shows a change in revs soonest. nothing about traction, clutch slip, transmission loss, turbo lag, just revs picking up. out of gear makes most sense, though doesn't prove anything as regards driving. it's what you need to heel toe though.

the sample rate of those datalogs on there (as far as i read anyway) makes them near useless in this instance.

i currently drive a 5 that i would say has pretty poor throttle response. not bad, but poor. i can't decide whether it's degraded over time, but i really have to try to heel toe. in the indy, it runs fireblade carbs on a 5" runner manifold. the throttle response in that is worlds away.
tom