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Heads up! Swapping to GT40P's. Need info...

  • Thread starter Thread starter MikeR351w
  • Start date Start date Nov 28, 2008

MikeR351w

Founding Member
Oct 8, 2001
207
0
16
Wisconsin
Nov 28, 2008
#1
  • Nov 28, 2008
  • #1
Hello,

I have a 93 LX 5.0 with a Edlebrock Perf. RPM II intake, unsure if it has a cam in it (People tell me it does by the sound of the engine), gutted exhaust (H-pipe) and under-drive pulleys.

I currently have the stock heads. When swapping out the heads for GT40P's, what else do I need to change... Which of the following parts can I keep and which do I need to swap out? If so, what parts and what brand do I buy to change it???

-Head gasket (What brand should I get?)
-Head bolts
-Push Rods
-Rocker Arms
-Rocker studs
-Valves
-Exhaust Manifold

Also, they guy who is selling ($125) the heads says they have a few bent intake valves. How much does it cost to replace them and get new seats??? Thanks a ton guru's!!!!!!!!!!!!!!!

 

stykthyn

I want to measure mine. It doesn't look that tall.
15 Year Member
Jul 6, 2006
5,232
2,652
223
gainesville
Nov 28, 2008
#2
  • Nov 28, 2008
  • #2
valves arent cheap. you are also going to need new springs as the low lift springs will allow the valves to float with an aggressive cam.

with the money you are going to put into them to get them ready for your engine(new valves,springs, machine work) I would look for a used set of trick flows or or at least another set of gt40 heads that dont have hosed valves. I can see you easily spending 600 on top of the 125 asking price to make them runnable.
 

RYC CUKR

Founding Member
May 19, 2002
1,437
1
38
Orlando
Nov 28, 2008
#3
  • Nov 28, 2008
  • #3
I paid $300 for a set of low mile p heads for my 93, swapped the springs out with the upgraded kit from Trickflow for about $110 at the time and put them on. With the bent valves and needing machine work done to the seats I would pass on them and see if you can't find either a good set of GT 40s or another set of Ps.

When doing a head swap I would toss the stock headbolts and put some ARP headbolts in. Last I recall they were going for $45 or $50, it has been awhile though. The studs are more expensive, closer to $100. I believe that I used FelPro HGs but I can't remember the part #.

You can transfer the rocker arms off you stock heads to the Ps or you can upraded to some pedestal mount roller rockers. I reused the stock pushrods and put a set of Scorpion roller rockers on my 93. You won't have to worry about rocker studs since E7s and P heads are both pedestal mount rockers unless they have been converted.

For headers I used the FRPP ceramic coated headers. I got a good deal on Ebay on some NIB ones. I would spend some time looking around and trying to get a good deal. I have heard that you can make other headers work with short plugs and 90* boots but In the end that just makes plug changes a bigger headache than they already are. Get a set of P specific headers. If you get a set of regular GT40s then you can use any of the usual headers BBK, MAC, FRPP etc.
 

asecretfile

New Member
Feb 11, 2007
228
0
0
Nov 28, 2008
#4
  • Nov 28, 2008
  • #4
I got my GT40p's for 150.00 no bent valves or anything I used the factory rods, rockers with my tfs1 cam for like 6 months before I went with rollers. Not saying that was the best idea but I didnt have a prob in the meantime

I used FRPP stainless P specific headers

For head gaskets I got this kit Felpro HS9280PT2 from Oreillys, probably ok for you unless later you plan on boosting



I just did away with the upper to lower gasket from the kit

lower to head I started with the more expensive felpro 1250's and leaked like crazy and I used the cheaper felpro ms93334 from this kit and rtv'd the coolant ports and front/back and never leaked a drop since
 
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