GT40P Head Questions
#1
GT40P Head Questions
I am looking into getting a set of gt40p heads with a e303 cam. Will my cobra intake manifold match up and will my exhaust headers match as well I have stock 5.0 heads with bbk shorty tuned headers. What other problems may I run into?
#2
Everything is going to bolt up. The only problem you may have will be the spark plug angle. I burned up several spark plug boots until I ordered some 90 degree angled boots. By the way, this isn't worth putting together and I wouldn't wish it on my worst enemy. Gonna run like CRAP. Trust me, did this exact build before I went ***** out and built my badass 347.
#5
This does not belong in the tech section OP.....
There is NO reason for it to run like crap and you DO NOT need a tune.......The P heads are ok but they are a PITA... The Cobra intake is the basicaly the same intake as the explorer intake and guess what the P heads come off of.....an explorer...
Do your build right and do not use a E cam... use the stock cam or get a trick flow or comp cam....
There is NO reason for it to run like crap and you DO NOT need a tune.......The P heads are ok but they are a PITA... The Cobra intake is the basicaly the same intake as the explorer intake and guess what the P heads come off of.....an explorer...
Do your build right and do not use a E cam... use the stock cam or get a trick flow or comp cam....
#6
^I'll have to disagree with you on the running like crap part. When I was trying to sift out my GT40P/E303 mess I ran across a ranger forum and bookmarked it. Since we can't post links, I'll post up some of the information that I found on this combination. This is from a PM sent by Michael Yount over on Corral:
"Do you have the stock GT40P heads? They are even more intake biased (relative intake/exhaust flow) than the stock heads are. If the head and/or exhaust system - exhaust flow is limited in the E cam application, the cylinder can't empty completely at low rpm. Consequently, during the overlap period, you get reversion into the intake which reduces vacuum and just kills idle quality. What's the rest of your exhaust system look like? I suspect anything you can do to free up exhaust flow will help with idle quality - however, I also suspect the biggest culprit is the head itself. What it really wants is an exhaust-duration biased cam, and one with a larger LSA -which the E is not. I can also email you some data on your heads that will illustrate the intake bias I referred to earlier. My guess is, unfortunately, if you're not happy with the idle yet, you're probably not gonna be happy with it."
"Do you have the stock GT40P heads? They are even more intake biased (relative intake/exhaust flow) than the stock heads are. If the head and/or exhaust system - exhaust flow is limited in the E cam application, the cylinder can't empty completely at low rpm. Consequently, during the overlap period, you get reversion into the intake which reduces vacuum and just kills idle quality. What's the rest of your exhaust system look like? I suspect anything you can do to free up exhaust flow will help with idle quality - however, I also suspect the biggest culprit is the head itself. What it really wants is an exhaust-duration biased cam, and one with a larger LSA -which the E is not. I can also email you some data on your heads that will illustrate the intake bias I referred to earlier. My guess is, unfortunately, if you're not happy with the idle yet, you're probably not gonna be happy with it."
#7
And??? There are ways to get around the small exhaust flow on all stock 302 heads.....such as 1.6 intake and 1.7 exhaust rockers......or porting of the exhaust side of the heads...or some advancing or retarding of the cam (not sure which but it would help).... The regular GT40's are the same way....
BUT thats what you get for running a E cam anyway.........
BUT thats what you get for running a E cam anyway.........
#8
Well, the OPs post was about running an E303 with GT40 P heads, not running GT40P heads with some other cam, or the E303 with some other heads, so keep that in mind when saying "that's what you get" and offering different cam selections. I know from first hand experience that this is an oddball setup that just doesn't mesh. I tried everything from base idle resets to you're rocker idea, to putting the car on the SBDS at the shop. I'm sure that what you have mentioned would help, but would it cure it?, I don't think it would.
#10
you have to be kidding right?? you're quoting Mr. self-proclaimed volvo enthusiest/ internet expert on the sbf.... lol, I 'D LOOK FOR TECH ELSEWHERE........FYI, I've worked on e-cam gt-40p set ups with no idle issues and smallish exhaust = Yount proved wrong