After WOT run car won't run, with really rough idle

[BruceH]

Wow, cracking the intake is impressive. I thought it could handle more abuse, makes you wonder about the ford upgrade that is also plastic...

Many things could weaken the intake manifold. The first suspect would be improper torque values and application.

 

[Sonicblue_s197]

That's pretty much what they said, all you guys were telling me it was a vacuum leak I checked everywere but never thought about pulling off the intake and checking it , I also haven't seen anybody push the stock intake past 20 psi usually they have a frpp intake or c & l intake. All I know is I'm glad I got my jpc sheet metal intake when I did cuz it's seeing 22 psi at 6500 rpm, once the intake is on there taking it up to 7500 rpm.

 

[BruceH]

Who put the intake on that cracked? Did they tell you where it cracked?

 

[Sonicblue_s197]

I put it on when I dropped the new motor back in but they had issues with it running on the start up so I'm not sure if they ever took it off. I followed the specs from ford when I installed the intake. From what he told me it had cracks on the bottom of the intake on the runners not sure how many, and there was a crack behind the throttle body too

 

[05moneypit]

That's pretty much what they said, all you guys were telling me it was a vacuum leak I checked everywere but never thought about pulling off the intake and checking it , I also haven't seen anybody push the stock intake past 20 psi usually they have a frpp intake or c & l intake. All I know is I'm glad I got my jpc sheet metal intake when I did cuz it's seeing 22 psi at 6500 rpm, once the intake is on there taking it up to 7500 rpm.

I've been putting 25psi in the stock intake for a few years with no problem. I know of at least two other guys that have run even more boost on the stock intake without issue.

Your engine ever backfire?

 

[Sonicblue_s197]

No its never backfired.