Cracked intake manifold?
 

Hey everyone, today I removed my intake to replace the gaskets because I was leaking a lot of coolant out the front (and some oil in the back). When cleaning it I noticed what looks like hairline cracks. However, I'm not sure if they are cracks or weird dirt formations because of heat. There were more that I couldn't re-find after I cleaned that part of the intake.

Potential cause: A while ago the plunger in my carb got stuck at full throttle, had to pull over (in neutral) and power off my car with it running at that high speed. My car has never run properly since, but I attributed that to going from an Edelbrock 650cfm to a used Holley 600cfm double pumper. It just runs a little rough and hesitates when giving it gas sometimes, but doesn't seem to make any different noises/hissing.

The intake is an aluminum Edelbrock Performer that was on a 351w in my 69 mustang.

Opinions? Sorry for the terrible pictures, its the best I could do at the moment.

http://i18.photobucket.com/albums/b1...y/IMG_2044.jpg

http://i18.photobucket.com/albums/b1...y/IMG_2046.jpg

http://i18.photobucket.com/albums/b1...y/IMG_2048.jpg

Eek, David. That does look like cracking to me, although I'll wait to see what the others say.

Thanks Tad. Anyone else have input? A couple friends of mine say cracked too.

I'm assuming I need a full replacement, correct? Or can a machine shop fine the cracks and weld them up for cheaper than a $200 new one?

Also, how is the Weiand 8023 Stealth manifolds? Will it cause any clearance issues with my 69 hood going from a Edelbrock Performer to this one? Right now I'm running no spacer with the stock air cleaner. I've lost some faith in Edelbrock since my carb went out and now my intake, so if this Weiand Stealth works well on a fairly stock 351w then I'll probably go for it.

http://www.summitracing.com/parts/WND-8023/

The carb I'm using now is a Holley 600cfm double pumper. Will it be providing enough fuel for my 351w? I'm thinking I should rebuild it since I have it off but want to see if its worth it.

I doubt anyone can TIG weld that for less than $200, unless you happen to know someone with a TIG welder.

How did your Edelbrock 'go out'? They're extremely simply carbs and there's not a lot to go wrong with them as long as they're not clogged up.

In any case, the 600 Holley should work fine for now. I'm running an Edelbrock 600 on my 331 and it pulls all the way up to 6200rpm. I'd rebuild what you have and tune it for your motor.

The internal plunger of my carb got stuck when I was passing someone going down Madonna, so it was close to full throttle. I thought it was the linkage, but it was all still perfect. I had to put my car in neutral and couldn't un-stick the throttle so I had to turn my engine off spinning that high. Oil was everywhere (mostly out of the valve covers)

My car hasn't run well since, and now I suspect that was from my intake being cracked. It makes sense now that this throttle sticking incident could have created too much pressure on my intake, creating the hairline cracks. I always blamed the used Holley I put on after.

I do miss that edelbrock 650 though, they are indeed extremely simple carbs. I still haven't quite figured out this holley double pumper.

What about the Weiand Stealth intake vs. Edelbrock Performer? Performance? Hood clearance issues for a 69 mustang?

http://www.summitracing.com/parts/WND-8023/