4" Inlet gains?

[slcook54]

Talking to Blaise about this today, my wheel on the 67 is actually larger than the 3" inlet, I was thinking about switching to a 4" inlet, has anyone swapped housing and possibly done back to back dynos or witnessed increased in power? Blaise was telling me, generally a his turbo should make 40-50 more hp than mine solely on the basis of inlet size alone.

[Def]

I could see that if you're flowing enough to choke the inlet(air is going sonic). Every little bit of diameter at that point will get you more flow before the turbo chokes out.


Now if you're talking about only running 450rwhp or something on your 3" inlet pipe, probably little to no difference with a 4" one.

[Shuasha]

I recall radowski saying that he hit a choke point at around 500whp with a 3" inlet on a GT35R.

[slcook54]

Thanks guys.

[moadster]

Blaise was telling me, generally a his turbo should make 40-50 more hp than mine solely on the basis of inlet size alone.


It's usually a 5-10% gain in power according to Precision at the maximum capacity of the turbo.

[slcook54]

It's usually a 5-10% gain in power according to Precision at the maximum capacity of the turbo.

Next mod = get to the maximum capacity of turbo. :devillook

[JordanMD88]

I recall radowski saying that he hit a choke point at around 500whp with a 3" inlet on a GT35R.

Supra Guys have said the same thing...

[jfdmas]

why would anyone opt for the 3in inlet when there is a 4in available?? When i was given the choice i desided bigger was better.:lol: so 4in ported S cover it was. But now im hearing that the ported S cover is less efficient then a basic 4in inlet.:confused

[slcook54]

why would anyone opt for the 3in inlet when there is a 4in available?? When i was given the choice i desided bigger was better.:lol: so 4in ported S cover it was. But now im hearing that the ported S cover is less efficient then a basic 4in inlet.:confused

How about the 3" works with the stock engine mount? Unless someone has run a 4" intake with the stock Motor mount? Don't know of anyone.

[nickdrivesm3]

but now you get a EMS mount and a 4" inlet!

[slcook54]

but now you get a EMS mount and a 4" inlet!

Lot more to do before that happens. :eyecrazy

[nickdrivesm3]

is your exhaust done yet?

[RRdawho?]

Its not just the motor mount thats the issue, its the fact that at AC is in the way, for bottom mount guys at least.

[e36'n]

Its not just the motor mount thats the issue, its the fact that at AC is in the way, for bottom mount guys at least.

Tell me about it...it was a bitch to fit a 4" intake and keep the AC.

[ParadigmGuy]

Hey Steve - you know that I'm on my way out right? And I'm bringing my DR's. Now is the time, Barona is open on the 11th. :D

[JordanMD88]

http://i94.photobucket.com/albums/l99/JOrdanmd88/DSCF1198.jpg

Cartech mount works great too :)

[jfdmas]

yep, cartech mount plus ireland engineering motor mounts and I have plenty of room. Im just lazy though.

[Shuasha]

Unfortunately, that mount won't work with the Turbonetics (used by Technique Tuning) manifold. Anybody know of one that does work?

[RRdawho?]

Tell me about it...it was a bitch to fit a 4" intake and keep the AC.


Care to share pics :stickoutt

[techno550]

a 3" inlet may be come "less efficient" at 500 hp, but "choke" is perhaps a bit extreme of a term there.

[slcook54]

Hey Steve - you know that I'm on my way out right? And I'm bringing my DR's. Now is the time, Barona is open on the 11th. :D

Yeah I know, talked to your Mom yesterday when I stopped by haha. :) I thought it was you wearing a wig or something, spitting image.

[Def]

a 3" inlet may be come "less efficient" at 500 hp, but "choke" is perhaps a bit extreme of a term there.

Agreed, a 3" inlet at ~50 lb/min isn't anywhere close to choking with atmospheric pressure driving it. The delta P between a 3 and 4" inlet probably isn't very large at that flow rate either.

[WCM3]

Care to share pics :stickoutt

+1. I think it is impossible. I had to go with 3" flex hose. Oh well :(

[m3jasper]

I'm not sure on how much more power you make, but I'm sure that it won't hurt. I know that George always recommends a 4" intake to anyone who is building their turbo e36's. If I remember, I will ask next time I see him.

[e36'n]

Care to share pics :stickoutt

Of course.


It's like this but the coupler was too thick so I had to use Aeroduct CAT hose instead. I later found out it's not recommended for negative pressure applications, but it was too late...
200839

Motor mount, e30 bushing and spacer:
200838

View from the engine bay:
200837

From underneath:
200840
200841

[ParadigmGuy]

Yeah I know, talked to your Mom yesterday when I stopped by haha. :) I thought it was you wearing a wig or something, spitting image.
:lol Yeah, she told me about that.