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Hi

if changing from a stock side mount cooler to a front mount but return to stock pipe. Is there any noticable throttle lag becasue of the longer piping compare to stock?

front mount for better cooling more option for future upgrade, or a Trust R-SPL type 13 stock mount, for no lag compare to stock?

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you also could go for the ARC FMIC that has the return piping on the same side, doing away with the need to have the piping go up and over the top of the engine... so shorter piping = better response and cooling (cos the pipe doesn't go over the engine) and another benefit is that your engine bay still looks relatively stock when the filth pop your bonnet.

I'm still waiting on mine to get here from Japan but when it does I will let you now the results (if your interested).

Disclaimer: This option was suggested by my mechanic, I am in no way smart enough to come up ideas like this :D

kewl. nice to know that there's no noticable throttle lag from a few different people.

now there's no more need for the trust stock mount cooler option, i can just decide which FMIC to go for. I am a sucker for brand name.... so I will be checking out either the HKS s type or the Trust V-SPL. any experience with either brand?

By the way, my car is a auto GTT, so not sure if HKS cooler will work. On GREENLINE web site it say "not suitable for auto", any ideas?

Hi guys, here is one I prepared earlier using an example of 4 intercooler setups and pipework we have actually used;

1. R33 GTST Standard Intercooler and standard R32 GTST pipework

150 rwkw = 27 lbs of air per min @ 13 litres of i/c & pipework

2. Supra Intercooler and matching 63mm pipework

180 rwkw = 30 lbs of air per min @ 15 litres of i/c & pipework

3. Standard GTR GTR and 63/75mm pipework

250 rwkw = 40 lbs of air per min @ 21 litres of i/c & pipework

4. Greddy 600 X 300 X 115 and 80 mm pipework

400 rwkw = 60 lbs of air per min @ 28 litres of i/c & pipework

If you look at the numbers you can see that the rate of air flow and the volume of I/C and pipework have a fixed relationship (27 = 13 , 30 = 15 , 40 = 21 , 60 = 28). This is not an accident, I designed it that way. The reason is I wanted to keep the throttle response as close what it was when the car had 150 rwkw, because I though that was very nice response.

The theory I followed was, the more power the engine produces the more air it needs. Thus if I keep the increase in the volume of air inside the inlet system in the same proportion as the power increase, then the throttle response should stay the same. This is based on the engine using the air in the same time frame.

So when people say they fitted a FMIC and have not noticed any less throttle response, my response would be, that is what I would expect. As long as they went from 150 rwkw to 180 rwkw. On the other hand, if there was no power increase then it would be simply physically impossible for there to be no decrease in throttle response.

The problem of poor throttle response arrises when you have a 220 rwkw engine with a 28 litre inlet system. This is something I see way to often.

Hope that adds to this interesting thread.

you also could go for the ARC FMIC that has the return piping on the same side, doing away with the need to have the piping go up and over the top of the engine... so shorter piping = better response and cooling (cos the pipe doesn't go over the engine) and another benefit is that your engine bay still looks relatively stock when the filth pop your bonnet.

I have an ARC as well. Pod in a box.

FC tuned for response rather than outright power.

Very snappy in traffic. No problems jumping those pesky V8 Commodores.

T.

you also could go for the ARC FMIC that has the return piping on the same side, doing away with the need to have the piping go up and over the top of the engine... so shorter piping = better response and cooling (cos the pipe doesn't go over the engine) and another benefit is that your engine bay still looks relatively stock when the filth pop your bonnet.  

I'm still waiting on mine to get here from Japan but when it does I will let you now the results (if your interested).

Disclaimer: This option was suggested by my mechanic, I am in no way smart enough to come up ideas like this :rofl:

i dont know if that theory is right, cause both systems have to back track at some stage. your one will back track over the cooler and up under the pod. whereas the other option goes up towards the inlet manifold then back tracks in front of the engine. probably would be very similar pipe lengths.

next option is to cut the corner like in my sig. but still not sure if that is the best option.

some argue that going back to stock piping needs a u-turn pipe at the fmic outlet that can reduce performance. i haven't noticed in mine as in fact i got 40kw extra, but i guess it depends on the quality of the pipework and as long as the u-turn is not too abrupt might be ok. but of course logically there'll be up to a certain point where a straight thru design will win, maybe e.g. above 400hp ?

So when people say they fitted a FMIC and have not noticed any less throttle response, my response would be, that is what I would expect.  As long as they went from 150 rwkw to 180 rwkw.  On the other hand, if there was no power increase then it would be simply physically impossible for there to be no decrease in throttle response.

so by installing just a FMIC = power gain, therefore no lag? or do you also need to up the boost which develope a bit more extra power?

how much extra boost can the stock r34 turbo handle? stock setting at 7psi?

so by installing just a FMIC = power gain, therefore no lag?

No lag, only if the power increase = the increasein capacity of the intercooler and its pipework. eg. If you put a 100% larger intercooler and make a 30% increase in power, there must be more lag.

or do you also need to up the boost which develope a bit more extra power

Boost is irrelevant. Airflow makes power

how much extra boost can the stock r34 turbo handle? stock setting at 7psi?

I wouldn't go over 10psi - if you wanna know why, do a search, there are plenty of threads on this subject. :rofl:

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