I'm trying to look for a turbo that fits what I need perfectly. My goal is around 500 hp, with max boost of 21 psi, and the best response turbo out there . My current turbo is BW S362 and based on the compressor map, it looks like max boost is around 24 psi, which I will never fully use. Therefore, this turbo is a bit big and I'm not maximizing the response of the turbo. I am currently boosting at 21 psi at high boost. My current supporting mods are below:

Pre turbo WI
AEM Ignition coils
Exedy twin plate
ID 725/2000 injectors
FMIC
Street port
And all necessary mods.

Since the preturbo WI shifts the compressor map a little to the right, it means that you can achieve a higher max boost on what used to be, let's say an 18 psi turbo. That same turbo can now be boosted at 21 lbs. Am I getting this right so far?

So let's say I want a turbo that maxes out at 18 psi, and with my preturbo WI, I can bump that up to 21 psi.

I realize that 18 psi for a smaller turbo is not the same for a bigger turbo. However, with this school of thought, what do you think the ideal turbo would be for an FD. A larger hotside is also ideal.

 

congrats, you have a nice group of mods.

21 psi and 500 hp requires an approx 7 square inches of compressor area, not what you have which is around 6.4. there are a few billet style turbos in the 6.4 area but they would be stretching for 500 which is 66 pounds per minute.

i suggest you check out my Turbo Comparisons thread (sticky Single Turbo section) for your options.

do not be afraid a a turbo in the 7 inch area as to spool and more importantly mid range power.

i have had good results w the BW S300 63. a touch over 500 at 21 psi w excellent midrange. inexpensive and OE quality build. if you wanted to spend a bit more the BW S300 64 FMW has a more efficient compressor and an uprated bearing assembly. both have rotary friendly large hotsides.

howard

 

Borg Warner EFR 8374 Turbocharger

T4 External 1.05 is your ideal setup for that power level and boost pressure.