too lean

[chubba]

i have an 87 t typ limited just bought had a frien put in on a dynno a/f came back 10/1 to 14.5/1 he tells me its way to lean and should not drive it am i missing something? boosting about 18 psi

 

[forcefed3.8's]

It should not jump around like that. What is done to the car? It sounds like a fuel delivery problem. You should be around 11.4

 

[chubba]

it is a built motor .30 over spearco intercooler precion turbo it was done by kenne bell? has a granattelli mas adustable hooker headers. im thinking of starting with the fule pump injectors ar 38 lb

 

[forcefed3.8's]

What size turbo? How much power did it make? The granatelli MAS might be an issue, but I would check fuel pressure when it is going lean. Might be pump, might be injector, might be MAS reading.

 

[chubba]

thanks i will get more answers on what i have i need to do some more research
it made 380hp 571 torqe

 

[forcefed3.8's]

If the pressure drops, then it is a pump issue. Those are some decent numbers for such low boost. Might be on the edge for those injectors too.

 

[Boost231]

got pics of your car? what about the dyno chart. you got pics of it?

 

[Nick Micale]

i have an 87 t typ limited just bought had a frien put in on a dynno a/f came back 10/1 to 14.5/1 he tells me its way to lean and should not drive it am i missing something? boosting about 18 psi

Yes, you are "missing" lots of other recorded data as well as info on the car.

If the car is basically stock, and using the junk pump gas, 18 psi is WAY too much boost as there is probably knock retard messing with the A/F ratio to start with?

Best to find someone with knowledge about turbo Buicks in your area to help you.

 

[huntsg]

I had a similar issue when I put mine on a dyno. I don't have a granatelli but mine turned out to be a bad MAF. It caused a major lean condition at WOT and RPM over 4500. I would start there.

 

[NicksTurbo6]

Stay away from the Granatelli MAF. They have had nothing but issues over the years, as they are very inconsistent with their calibration. Always use a GM/Delco MAF.



Nick

 

[berserker6]

Sorry if I missed it. But what chip? Is it burned for your injectors?

Upgraded hotwired fuel pump?

Are you monitoring fuel pressure at WOT?

Are you monitoring for knock?

What is your base fuel pressure set for?

Do you have a scantool to monitor AF at WOT?

 

[chubba]

i just bught the car i have limited info it an older build i belive its running the stock pump mas is grannatelli spearco intercooler 36 lb injectors 1.65 rockers garrett turbo dont know the model somesort of mild cam was set up on nos still
have the bottel not plumed 3.73 gear 2800 stall converter im still trying to figure out what i have i dont have a scan tool any sugestions on where to start?

 

[chubba]

this is the car

 

[Razor]

i just bught the car i have limited info it an older build i belive its running the stock pump mas is grannatelli spearco intercooler 36 lb injectors 1.65 rockers garrett turbo dont know the model somesort of mild cam was set up on nos still
have the bottel not plumed 3.73 gear 2800 stall converter im still trying to figure out what i have i dont have a scan tool any sugestions on where to start?

Start with a scantool like a scanmaster.
2.. get a new fuel pump and hotwire kit

3.. work from there..

No flooring the car anymore until you have a scantool hooked up. Unless you want to build a motor sooner than latter.

Fuel pump is a no brainer.

 

[berserker6]

thats a beautiful car. forget the NOS. get a chip from turbotweak and a scanmaster. upgrade the fuel pump. and definately no jumping on it til that stuffs in the car. take BABY STEPS:wink:

 

[pontiac69fb]

An air fuel of 14.7 is normal at idle and cruise but it is not good at wot. 10.7 is pretty safe for wot, I would say lets see the dyno sheet to confirm the air fuel's. PS what mods are done to this car?

 

[ALVAROG1983]

Reply

View attachment 119300

that is a nice car i remember when it was for sale take care of it.

 

[chubba]

thanks i finaly got it for a decent price unfortanatly it comes with limited info of whats been done to the motor

 

[Rafs-T-Type]

Start with a scantool like a scanmaster.
2.. get a new fuel pump and hotwire kit

3.. work from there..

No flooring the car anymore until you have a scantool hooked up. Unless you want to build a motor sooner than latter.

Fuel pump is a no brainer.

X2....stay off that gas!