7mgte boost questions

**kemicalx** · 29-09-2006, 10:46 AM

I'm going to be winding up the boost on 7m soon, I've been thinking 12-13psi for my full boost map, and then just the standard 7psi for daily driving. I've read that pushing 14psi out of the ct26 is pretty much the limit, why exactly is that?

A couple of other things,

Will the standard 440cc injectors be able to provide enough fuel for the increased power? I remember Dong saying they'd be good for about 290kw but I don't know if that was at the fly or rear.

Also does anybody know how much the ignition should retard for the extra 6-7psi? The car will be getting a propper dyno tune, but i'd like to know some figures If anyone has them.

Finally, does anyone know the maximum boost the standard BOV on the 7mgte can hold. If i'm running over 10psi I'm thinking i'll need to upgrade to avoid boost leak. And i'm thinking i'll get one of those cheap bosch jobbies http://www.s4biturbo.com/art-dvtests2.php

anybody thats wound up a ct26'd 7m and had it dynoed let me know what you got, and what supporting mods you were using.

Thanks guys,
Ash

**Stomps** · 29-09-2006, 11:04 AM

hey dude, i got mine dynoed at 11.5 psi, made 278rwhp then clutch slipped, Mick (my dyno dude) said the turbo had another 3 to 4 psi in it and would have easily made over 300rwhp... he has worked on 7m's most of his life, so he knows his shit..

My relevant mods were

Turbo A cooler, 3 inch zorst, no cat (home made, kinda dodgy), home made 2.5" cooler piping, HKS FCD (allows to run over 10psi) Turbosmart bleed valve. I also had an SAFC on it but at no point does it add fuel, just takes fuel away to make it more efficient.

ISSUES
factory injectors have more in em then the turbo can produce.
Factory cooler tends to blow at over 14psi
Dunno bout the timing, sorry dude
HKS fuel cut defender is the only out of the box one that works on 7m computers.
i ran my ct-26 on massive boost for a while, gauge showed 17psi, turbo made funny noises, then proceeded to blow its oil seals.. DONT DO THIS!!!

Stomps

**kemicalx** · 29-09-2006, 11:37 AM

In all honesty i don't see my turbo lasting all that long, i'm sure it's well due for a rebuild. So i'll have a play with this one, and if i see any rebuilt ones pop up for sale, snap them up. if not wait for this one to go, and have it rebuild.

Apart from the full exhaust (i'll only have the dump pipe done) i think i've got all the other bases covered

Though, i may want to go easier on the boost.. maybe only 10psi. It'll save the turbo some life, and i couldn't be fucked changing the clutch immediately. If i mapped out the boost to sit at 10psi up to about 3500rpm then rise gradually to hit 13psi by 5500 do you think it would save the clutch?

**EldarO** · 29-09-2006, 03:29 PM

running 11-12 psi here right now, stock EVERYTHING.

shes holding up fine, although it is using more coolant than fuel :/

was planning on running 13psi, but cant be assed adjusting the bleed valve again.

will get cooler and piping soon!

Eldar.O.

**Stomps** · 29-09-2006, 04:04 PM

dunno bout the clutch dude.. mine took a massive battering when i had a td-06 and was making over 300hp.. then i put my ct26 back on and didnt treat the clutch any better.. ATM its fairly safe to say my clutch is fucked.. i cant make full boost in any gear coz it just slips, and im only running 9psi atm

talking to a few people bout clutches for mine, they all say the factory ones dont respond too well to more then factory power.... i will be going a big single when i get it done..

Stomps

**BlackSupra** · 30-09-2006, 09:30 AM

Originally Posted by kemicalx

Will the standard 440cc injectors be able to provide enough fuel for the increased power? I remember Dong saying they'd be good for about 290kw but I don't know if that was at the fly or rear.

Around 290rwkw before they lean the hell out.

**kemicalx** · 30-09-2006, 11:18 AM

well no problems there then lol, don't think i'll be hitting 290 any time soon

**kemicalx** · 06-10-2006, 08:31 AM

Originally Posted by kemicalx

Finally, does anyone know the maximum boost the standard BOV on the 7mgte can hold.

Don't want to waste money on a bov if i don't need to.

**chris davey** · 06-10-2006, 09:14 AM

re timing, I run 21-23deg timing between 3000rpm and redline at 14psi on my single turbo 1jz on 100octane fuel.

Don't know how much different a stock turbo 7m would be but if you start at say 19 at 3000, ramping up to 21 and redline and check for knock (assuming you already have a good safe AFR) then I would think that would be ok. Might be a good idea to check out sf.com for some tuning advise with 7m specific info.