how much boost for the 440

[need new tires]

i am working on a customers car and the car is:
full
na-t : stock ct-26, rebuilt 440's, turbo intake mani, p&p exhaust mani,factory piping and bosh recirculated and turbo FPR.
10:1 CR
MHG with ARP's

the goals where run 6-8 psi (6 is a target) but the car is hitting 6 psi at half throttle.

i am putting the wideband in today but what can i expect ?

how can i turn the boost down?

 

[Supraboy89]

get a mbc

 

[CRE]

Yeah, I'd add a boost controller to the mix. The stock 7M-GTE 440's have been shown to be pretty reliable up into the lower teens. I would try to keep the boost around your target of 6-8psi and keep an eye on the WB to see how the injectors are faring.

 

[need new tires]

well this morning i went a put a WB in and well i about craped my self A/F 26-27:1:runaway:

well i drove it over to a friends house and we loosened the AFM back to stock and the a/f went down to 19-20:1. well he put his hand over the manifold and this "hiss" went away(injector wasnt all the way seated)and a/f went to 15.4-16.1:1:naughty: now the car runs like a champ minus the tps being a little off.
so now i am changing the last few things and i should be able to play with the car for a little bit.

back to topic even with the 10:1 CR will 8psi be well in the safe range?

 

[Sawbladz]

get a mbc

Might be confused but I dont think you can turn the boost down past what the wastegate spring gives you. I will search and report back later.

 

[Sawbladz]

Read this thread.

http://www.supramania.com/forums/showthread.php?t=43518&highlight=spring+wastegate

You can't do it with an MBC...

Also...that compression ratio is even higher than a standard GE. I'm not an expert nor have I ever seen anyone on here run a high compression motor with a turbo so I can't really comment to well. Are you sure about your compression ratio? There's always race gas

 

[935motorsports]

Target is 6?

Unless you are using a bone stock crush bent exhaust, it is going to boost more then 6.

My advice is to not raise the boost AT ALL for now. Once you have a 3" exhaust on there, plus intake, you are going to be boosting more the 8.

If you convert it turbo electronics, you can boost 10-12 safely.

 

[need new tires]

well as for exhaust i am running a stock setup with gutted cats(they where litteraly smoking do to being plugged)

as for the CR yes i am sure of the number.

as for the car it pulls harder that any supra i have been in(thats all the way up to 479wrhp) in 1st and 2nd but 3rd just falls on its face and goes hard core lean . 4th is around the 12.4-13.1:1 numbers(havent pushed it). 5th havent tried

i still havent gone WOT most was 75% in 2nd but let out due to bad tire spin.

the car is hitting boost super early like 4-5psi @1900-2100. i am still afraid to even get on it till i can get the a/f more stable.

note: i own 4 turbo supras and then this na-t. i also mod the local mk3 group so i am not a stranger to these cars. i just havent seen a high CR na-t and figured what the hell, why not.

questions
i have a high idle around 1500 how can i get it down?
i am at stock timming(10 degrees), should i pull it back further?
anyone have a clue what causes 3rd to fall off and go nuts on the a/f?