HP Gain with these mods?? noticible?

[overbaugh240]

Alright guys i finally have my swap done... i took it to a muffler shop and they were out of 3'' pipe so for the time being to just quieten it down i got 2 1/2'' put on .. they made the downpipe and everything with 2 1/2'' pipe no mandrel bends . correct me if i'm wrong but wouldn't a 2 1/2 inch pipe be way to small especially in the bends?? well never the less i have the car running now it feels strong thru fist and second seems to fall on its face a little bit after that, plus most power is lost after 6400-6700 rpms... ok here's the question i'm ordering a 3'' downpipe and 255lph fuel pump from heavythrottle... now after i get the downpipe and i get 3'' pipe ran all the way back will there be a noticible difference.. i've heard mixed opinions about this.. any one notice a difference when they did these upgrades???i know it sounds like a stupid question but i just wanna be surethanksChris

[Phax]

You will notice a significant change when you get the downpipe and mandrel bent exhaust. Your car will rev all the way to redline. Keep in mind though that your stock turbo is pretty much done around 6500rpms.

[overbaugh240]

ok now with the downpipe and new 3 inch all the way back and the new fuel pump... now if i add a boost controller and turn the boost up to 10 psi.. i have a stock smic so i dunno how high i can go with the boost.... where would that put me?thankschris

[usdm_180sx]

I have a similar setup. I have an s14 sr boosting at 7lbs with the stock smic and a 3" dp but I still have my HKS exhaust w/60mm piping from my ka. It feels strong but like a restrained beast. I also have a Tomei fuel pump. Last night I drove my friend's s14 with a red top. It has a 3" downpipe, Apex exhaust, stock (ka) fuel pump and is boosted to 10lbs of boost. What a difference. It feels totally unrestrained! Yes it will make a big difference.

[Phax]

ok now with the downpipe and new 3 inch all the way back and the new fuel pump... now if i add a boost controller and turn the boost up to 10 psi.. i have a stock smic so i dunno how high i can go with the boost.... where would that put me?thankschris

Go read the STICKY at the top of the RWD SR page. It is well written and already answers all of your questions.

EDIT: The sticky is gone?!

At 10psi, you're going to be making ~220hp at the crank. If you're going to start upping the boost, make sure that you get EGT and A/F gauges. The SMIC should be good to 10psi, but you're going to want to keep your eye on exhaust temps.

[f150intally]

S14SRpilot,tell your friend to get a fuel pump. I would personally not even run stock boost with the stock fuel pump. Cheap insurance at $90 for high output walbro 255. running the stock pump is a good way to melt a piston.

[usdm_180sx]

S14SRpilot,tell your friend to get a fuel pump. I would personally not even run stock boost with the stock fuel pump. Cheap insurance at $90 for high output walbro 255. running the stock pump is a good way to melt a piston.

My bad. IIRC he installed a Blitz fuel pump

[f150intally]

cool...

-jay