minor hesitation: need suggestions

[Trickflow.GT]

is the maf cal'd for #36 injectors?...if not take the 36's out and put your stock 24's back in...

 

[cdsmith_2002]

The new parts are matched. 36# calibration MAF and new 36# injectors.

I wanted enough fuel to handle a super charger later this summer. I chose the 36# set up because it should be good for 350-400 boosted HP. I've already got a ZEX kit to install to fill the gap until I have money for a supercharger. I thought I was doing the right thing with the 36# parts. 240HP+125HP=375HP.

The Ford Racing catalog, page 136 states that 24# injectors are only good for 265 blown HP. Why would I stick with a 24# system? Even with the power adder, it sounds like 36# will not idle well???

 

[cdsmith_2002]

common theory is that the largest you should run on a stock motor is a 30# injector. Any bigger than that, and the injector just isn't opening enough for the fuel to atomize properly, and you get a rough idle!

where did you hear this crap? common sense tells you on a stock motor you run a stock injector. 24 #er's would be too big for him right now. 36#er's are gonna have him running pig rich.

How can 24 be too large? 24 is the stock Cobra size. The chart from Accel recommends 30# for up to 350HP and the 36# for up to 400HP. I have to admit that I based my purchase off of a couple of books and manufacturer info. I did not spend any time on the Forums. I've only had this car for about 8 months. I'm not a 5.0 veteran, that is for sure!

 

[cdsmith_2002]

I called this Pro-M this morning (very helpfull Tech Support by the way). It turns out that I have the wrong part #. There is a different calibration required for the Cobra ECU. The one from Jegs is for a GT ECU. The Cobra MAF is not a stocked item. :crying:

I'll report back when the correct MAF is installed.

 

[Wayne]

well while you wait for the maf cal tube check your throttle position sensor with an ohm meter it may have a bad place in it that caused the hesitation problem to start with. Hope this helps.

 

[cdsmith_2002]

I wish! That was about the first thing I tested. It sweeps nice and steady. I sure was hoping for a bad spot in it.

 

[ScottyDsntKnow]

I called this Pro-M this morning (very helpfull Tech Support by the way). It turns out that I have the wrong part #. There is a different calibration required for the Cobra ECU. The one from Jegs is for a GT ECU. The Cobra MAF is not a stocked item. :crying:

I'll report back when the correct MAF is installed.

Swapping to a T4M0 would also solve your problem.

 

[cdsmith_2002]

Whats a T4MO? A Gt ECU I presume. I'm hoping the MAF arrives on Monday.

 

[Steven]

yep, its the same one in the 95 I have.

 

[cdsmith_2002]

The correct 36# calibrated MAF arrived and is working just fine. It has a nice idle and the original problem is completely gone. :banana: It is not obviously running rich and it is idling as good or better than with the original 24# set up. Time to bolt on the ZEX kit and possibly get it tuned.

Thanks to everyone that put there 2 cents in. I learned a lot. :TY:

 

[ScottyDsntKnow]

You NEED to get the thing tuned, I need to get mine tuned too lol. You're leaving alot of power on the table if you don't.

Not to mention that the J4J1 computer(as well as the T4M0) pulls timing between shifts and is a VERY bad tune from the factory. A good tuner will remove that stupid tip in retard and give you a more aggressive tune.

You also could have had it tuned and the tuner would have tuned for the MAF you had in there. That's actually the PROPER way to do it but "calibrated" mafs work fine for the most part. My Bullit 24lb maf has worked fine for years.

 

[cdsmith_2002]

A dyno tune is part of the plan. I need to install the ZEX kit first (not to mention I want a Kenny Bell) so that can be part of the equation. I need to do some more research too. I have not even searched this forum for tips yet much less talk to the local Mustang shop, http://www.paulsautomotiveengineering.com/.

 

[Stangbangin]

common theory is that the largest you should run on a stock motor is a 30# injector. Any bigger than that, and the injector just isn't opening enough for the fuel to atomize properly, and you get a rough idle!

where did you hear this crap? common sense tells you on a stock motor you run a stock injector. 24 #er's would be too big for him right now. 36#er's are gonna have him running pig rich.

How can 24 be too large? 24 is the stock Cobra size. The chart from Accel recommends 30# for up to 350HP and the 36# for up to 400HP. I have to admit that I based my purchase off of a couple of books and manufacturer info. I did not spend any time on the Forums. I've only had this car for about 8 months. I'm not a 5.0 veteran, that is for sure!

You initial post only stated sometihng about a hesitation and nothing about a power adder so yea it makes sense now. But your hesitation was probably being caused by your maf on its way out not for lack of fuel since you don't really have any major mods.

 

[cdsmith_2002]

Right on. Since I was forced to buy parts, I wanted them to fit the future plan.

 

[Stangbangin]

Right one. Since I was forced to buy parts, I wanted them to fit the future plan.

now go drive it hard so you can break parts and upgrade those too....thats the name of the game.