Thread: 4-1 Header (3") with 60mm Exhaust?

Now all I have in my SR20ve is sr16 cams and SR16ecu tuned with Greddy emanage + a Pop Charger so you would say very mild 'bolt ons'

The existing exhaust is 60mm w/h is 2.36" (came from Japan with that).

I want a 4-1 header from GregV but it comes with 1.75", 2.38" collector but the rest of it (part with flex pipe that merges with rest of exhaust) 3". The 3" part is where have an issue because that will be leading into a much smaller 2.36" pipe. That is more than 0.5" step down. Is this workable. How will this affect the performance of the car?

I have stock header now.

And please don't tell me to go 3" to match the header. I MAY go 3 inch but not now. If I do other upgrades like cams I will go 3" but NOT now. 2.5" would have better but doesn't make sense to go from 60mm to 2.5" now either - 0.14" difference.

Again, I'm concerned about going from 3" to 2.36"

Spoke with Greg and he said it would be at least better than what I have but what do you guys think?

Peace

definatly better than what you have now, but of course not optimal power wise. you would probably be losing 3-5 hp with that exhaust, compared to a 3" but you will definatly see a large gain from stock. i would go and re-tune the car after header installation.

I know I would need to re-tune.

Thanks for the a very good (maybe because it's a favourable response :rofl first answer.

Was just concerned about what effect going from big to small would have.


Peace

Are you concerned about the power loss? or the noise?

Power loss?
I have stock header now with the 60mm exhaust so by getting this new header, I expect to GAIN power! If the 2 different diameter sizes, meaning the header and catback will cause me to lose power then I wont bother with it. That's the reason for the thread. Just wondering how the car would behave.

Noise?
There is no cat on it now but it has 3 resonators so it's not loud. The header alone should not make it any louder.

Peace

When my car was boosted on a t25 setup I had a 3inch downpipe mated to a stock cat and greddy 60mm catback. The car still walked a ss camaro and was still fun to drive. Could I have gained another 10whp..sure..who cares..Just put it on and drive your car dude. You can always upgrade next year.

Respect boss!

I am loving the two responses I have gotten so far. Wonder if a should close the thread b4 I get some -ve ones?

Well a couple of things. 1 4-1 hangs below the Xmemember. I haven't been back to Jamaica in a long time but what I rem were some crazy pot holes that would end the life of that nice header. Whats the gain from that header anyway? haven't seen any dyno charts from it.

Good Point. Will do some measurements and see. I have on Tein coilovers but car not much lower than stock.

About 7-10whp gains I assume

Plus it should feel much better up top

Peace