[middleagecrisis]

Just put my 5.0 back together after installing ported E7's and have been having cold idle problems since. I thought it might be the TPS or Idle Air bypass, so I checked them both. TPS was set at .985 volts with throttle completely closed, 4.6 volts completly open. Then I started car with the idle air bypass disconnected and after it warmed up set the idle at 850 (I'm running an F-303 cam). At this point the car was idling fine. I shut the motor off, reconnected the IAB and the car would not idle! I went throught he whole routine again and had to really crack open the throttle to get it to idle at 1200. Reconnected the IAB and the idle shot up to 3000. The car hauls ass at full throttle, but has a slight miss at cruising speed. I've swapped the mass air meter with no improvements. The intake is a GT-40 w/24 lb. injectors and fuel pressure set at 36 psi. I'm running out of ideas, somebody help!

 

[Oxidizer187]

Did you clean out the IAC motor? I am not sure if they are in the open position when they are disconnected or not. You can take it to an Autozone to have it tested. No vacuum leaks or disconnected hoses?

 

[middleagecrisis]

I have not cleaned out the bypass valve yet, but will do that tomorrow. What I can't figure out is how it could cause an idle decrease after I set the idle initially with the IAB disconnected, seems like it would only "up" the idle as required. Thanks for the suggestion, I'll have the zone check it out.

 

[Oxidizer187]

I'm not positive if it is fully opend or closed when it is unplugged. If it is and it closes slightly when plugged in if it has carbon build up it could restrict the flow. Just an idea. Good luck.

 

[middleagecrisis]

Can anyone tell me the correct procedure for setting the idle with regards to the Idle Air Bypass solenoid?

 

[Matt93Cobra]

Go to www.corral.net , click Technical Articles and you can find it there

 

[ssccoupe]

can you notice any big gains from the ported e7s?? I know this is kinda off the subject but ive been considering porting a set of e7s and just wanna know if its worth it..?? I would have stuck with the 19lb injectors.. i think 24s might be a little much for that combo.. just my .02cents..

 

[middleagecrisis]

Ported E7's

My first choice would have been to get a set of aftermarket heads, but I was strapped for cash. I put about 8 hours worth of labor into the port job. If you paid a pro, it would probably be cost prohibitive. I gasket matched the ports, blended the bowls and smoothed all ridges and rough spots. I don't have dyno figures or flow numbers, but can tell you the car pulls very hard all the way up to 6000. I still have the previously mentioned idle problem but I don't think that's related to the heads. It's worth noting that although I've home ported several sets of heads before, but I had a knowledgable friend check my work.

 

[middleagecrisis]

Matt93 Thanks! I've printed the procedure and will give it a try.

 

[ssccoupe]

Thanks for your info... I have friends that have a several sets of stock e7s they said i could have. ive read several articles about porting your own stock e7s and what ive read they said its hard to really mess anything up with porting the intake and exhaust ports.. i think i could do that pretty easily,, its just cleaning up the bowls and combustion chambers that i dont wanna screw something up. what gaskets did use to port match?? Have you seen the powerheads in the 5.0 mags?? www.powerheads.com the look pretty good but cost like 600 bucks. and they are just stock e7s with port work and new valves and all the other stuff..

thanks for you info man..

later

 

[middleagecrisis]

On the intake I used Fel-Pro 1250's and on the exhaust I used a stock Fel-Pro gasket for the porting templates. The main thing to remember is any ridge in the flowpath will "tumble" the airflow, so run your fingertip over your work and check for smoothness. I don't have any experience with the powerflow heads, but if you had to do a complete valve job and maybe replace some valves you can easily get into that price range. good luck.