7cm vs. 6cm

[punishercb]

I've tried searching but didn't have any luck. What is the advantages and disadvantages to upgrading to this? A guy's offering me a 7cm housing for 65 and I'm tryin to figure out if it's worth it.

 

[Black95TSIawd]

the 6 and 7cm turbine housings will not mate to our t25's. The 6cm is smaller and offers quicker spoolup but the 7cm makes more power.

 

[1993eclipseGS]

I never understood that part about faster spool up with the smaller housing. I thought, Being port work is suppose to make you spool up faster, woulden't just changing to a 7cm housing be better?

 

[punishercb]

Sorry, I should have specified. I just bought a 14b and another guy is offering a 7cm housing. I just don't know if it's worth it for 65 bucks

 

[notractiongst]

A Smaller housing increases spool up by increasing exhaust gas velocity..

 

[90blacktsiawd]

I understand about how a smaller housing should spool faster but have less top end. And vice versa for a bigger housing. But when i got my 14b ported out to 7cm it spooled a couple hundred rpm's sooner. Full boost by alil under 3k. Now on my evo 16g with the factory housing i still hit boost just under 3k and thats on a 7cm housing.

 

[Steve93Talon]

I understand about how a smaller housing should spool faster but have less top end. And vice versa for a bigger housing. But when i got my 14b ported out to 7cm it spooled a couple hundred rpm's sooner. Full boost by alil under 3k. Now on my evo 16g with the factory housing i still hit boost just under 3k and thats on a 7cm housing.

Porting a 6cm housing out to a 7cm gasket isn't the same as using a 7cm housing. Just because you're opening the throat up, the scroll size is still smaller. Think of a funnel. If you have one with a 1/2" hole at the bottom and it opens up to 4" at the top, then you "port" the opening at the top to 5", are you flowing any more through the 1/2" hole? No. But if you make that bottom hole 3/4", you'll increase flow.

 

[1993eclipseGS]

Thank's for the explanation.

 

[punishercb]

Cool, that makes sense. So does anybody have a 7cm housing? When does it reach full boost? I don't know if I want alot of turbo lag.

 

[Steve93Talon]

I run a 7cm on my 14b, with 272s no less, and it spools fine.

 

[Turbo Talon DL]

Ok, so I just got the wild idea of porting my old cracked 14b turbine housing out. I guess im gonna take it off the center section and port turbine inlet/outlet, and what else? I've never done this before and wanna flex my muscle at it. Any 'tech tips' and suggestions would be helpful. Im not too concerned about turbo lag, as I think its highly overrated..

 

[Steve93Talon]

http://www.vfaq.com/mods/porting-turbo.html

 

[babyman0737]

Someone posted about needing a 7cm turbine housing. PM me for details if you'd like one.