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Discussion Starter #1
I am about to get my hands on some GT40ps, one site said the need of new headers is a myth it will just be hard to replace 2 of the spark plugs. I was just wondering what I should do with them, should I just put them on or replace anything? Thoughts?
 

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get either longtubes, or P specific headers, no other headers will work
 

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PPl say they have no trouble with stock headers but the must use a few 90 degree plug wires. And some say you gotta hammer the headers a bit and some say they dont work at all. But you can get Mac BBK FordRacing and there is a few more brands. Can you say for sure the valves seet well and have good seals? If you ever plan on a cam you might as well get a comp spring kit or trick flow.
 

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Discussion Starter #4
I will probaby change my headers anyways, but people were saying also to replace valve springs, pushrods, rollers, cams, and to port the heads. Anyone want to chime in?
 

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From what I understand the P heads have oval exhaust ports and you need special headers, could be wrong. Try and find Gt40 heads, so when and if you upgrade standard long tubes will work.

And yes port and polish, valve springs, before putting on the car. You only want to have to do it once. You dont know where those heads have been.

The general consensus I get at the track is that its just as good almost to go with ported and polished E7 heads if youre on a tight budget.
 

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Discussion Starter #6
I am on a semi tight budget, but what is the average price to port polish and replace valve springs on gt40p heads?
 

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I wouldn't worry about the lifters if they are good.
Trick Flow has a decent spring/retainer/clip setup for ~$135 last time I checked.
Invest in a set of roller rockers, I like 1.7s especially with the stock cam. I use Crane's 1.7s with no issues.
Have a shop check over the heads, make sure they're flat and all is good. A new set of valve seals wouldn't be a bad idea.
I had my machine shop do a pretty extensive gasket match port job and regrind the valves for $500 I would recommend spending this cash.

I use non-P heads, but as far as GT40Ps vs. non-P GT40s I really think it's 6 of 1 half dozen of the other. They both have their ups and downs, very minute ones.

As far as intakes, search craigslist and ebay for an Explorer intake. Don't overpay, they are much better than stock but no gold mine finds. They can benefit from port work as well, look up tmoss on here. He does a wonderful job.
If you want to go another route Edelbrock Performer RPM II is a sweet manifold, my tuner really likes them.
 

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Discussion Starter #8
I wouldn't worry about the lifters if they are good.
Trick Flow has a decent spring/retainer/clip setup for ~$135 last time I checked.
Invest in a set of roller rockers, I like 1.7s especially with the stock cam. I use Crane's 1.7s with no issues.
Have a shop check over the heads, make sure they're flat and all is good. A new set of valve seals wouldn't be a bad idea.
I had my machine shop do a pretty extensive gasket match port job and regrind the valves for $500 I would recommend spending this cash.

I use non-P heads, but as far as GT40Ps vs. non-P GT40s I really think it's 6 of 1 half dozen of the other. They both have their ups and downs, very minute ones.

As far as intakes, search craigslist and ebay for an Explorer intake. Don't overpay, they are much better than stock but no gold mine finds. They can benefit from port work as well, look up tmoss on here. He does a wonderful job.
If you want to go another route Edelbrock Performer RPM II is a sweet manifold, my tuner really likes them.
What about the trick flow street heat intake kit, do you think this provides more power than the explorers intake set up?

TRICK FLOW STREET HEAT INTAKE MANIFOLD KIT WITH BLACK UPPER 5.0 1986-1995 - CJ Pony Parts, Inc.
 

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Port the heads if you want, I guess prices vary, I called Rubles Racing in Springfield,Mo and they wanted $600 for a port job alone but that was also flowbench time, they said they would have them flowing all the were capable of flowing (prolly 205-210CFM). But if you have any ideas of getting a cam you need to stop and find out what cam you will get and get the intake that matches the cam RPM range.
 
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