Ford Mustang Forum banner
1 - 8 of 8 Posts

·
Registered
1988 Ford Mustang GT with 347 Stroker
Joined
·
2 Posts
Discussion Starter · #1 ·
What’s up guys, I’m having a problem with my newly built 347 stroker. It has a Scat crank, Wiseco forged piston and rings, comp cam extreme energy cam and lifters, Liberty performance Rockers, AFR 185 heads, 36lb trick flow injectors and a Pro-m 36lb mass air flow. The problem my turner is having is when sitting at idle it starts to run rich. He’s telling me my brand new MAF is bad. Anyone having similar issues or have any ideas what it could be?
thanks
 

·
Administrator
Joined
·
8,101 Posts
Welcome and thank you for joining ALLFORDMUSTANGS!
Please read the Site Rules if you haven’t already.
We encourage you to complete your Account Settings.
If you need help posting, please read this FAQ.

We’re happy you have chosen to be a part of our community.

Someone will be along shortly with advice.
 

·
Registered
Joined
·
790 Posts
I had maf "pegging" at higher rpm on a stock 95 mustang MAF. doubtful you maf will peg at idle. Is it in open or closed loop when it starts to drift? Cars going to want less fuel at idle as it heats up.
 
  • Like
Reactions: Cobrajet67

·
Registered
1988 Ford Mustang GT with 347 Stroker
Joined
·
2 Posts
Discussion Starter · #4 ·
I’m really not sure, I will find out when I talk to the tuner today. I appreciate the response. Another thing I was thinking was I installed a dual electrical electric fan kit with the Dakota Digital relay controller kit. It’s currently set to run anytime the engine is running. Im wondering if those fans are somehow throwing what the MAF is reading after the car warms up
 

·
Registered
Joined
·
790 Posts
I’m really not sure, I will find out when I talk to the tuner today. I appreciate the response. Another thing I was thinking was I installed a dual electrical electric fan kit with the Dakota Digital relay controller kit. It’s currently set to run anytime the engine is running. Im wondering if those fans are somehow throwing what the MAF is reading after the car warms up

Shouldn't have any effect. Fans come on when hot, car requires less fuel when hot. What are you tuning on? Stock ECU?
 
  • Like
Reactions: Cobrajet67

·
Registered
Joined
·
790 Posts
36lb injectors on a naturally aspirated small block sounds like it might be a bit much. How did you come to the 36lb injector determination or choice exactly?
If they're decent injectors he should be ok. I have 34# on mine. Max duty cycle is only 61% on my current build. EV14 injectors though, so a nice spray pattern.
 

·
Tech-Advisor
2014 GT, 1967 Fairlane GTA
Joined
·
4,765 Posts
It looks like with 350hp at the crank you would need 27lb injectors and at 400hp you would only need 31lb. I would think that most people aren't exceeding that HP easily with a small block especially without forced induction. You would need to be around 450hp to need 36lb injectors on a naturally aspirated engine. I get that extra headroom isn't generally a bad idea but too large of an injector can be a problem at idle or low fuel demand conditions at lower RPM.
At idle with injectors that are too big it will tend to run too rich. A bigger injector has a minimum amount that it can spray and the spray pulse can only be made so short. If it's not opening/closing quick enough to maintain a decent air/fuel ratio then you'll get an overly rich condition that gives poor eye watering idle, bad drivability, high fuel consumption, and it can destroy your cats. The computer can also only adjust for so much. I think Krem12 might have been touching on that when he asked about the computer being stock or not.
I don't have any specific knowledge on injector generations/types so for that I definitely default to Krem12 who would know more about it.
 
1 - 8 of 8 Posts
Top