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any hop-ups while engine is torn apart and replacing headgaskets?

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05silverado4x4

New member
hey my first post on the forum,

so i just bought an 02 grand prix gt 3.8 for $500 with blown headgasket. since i will have the top end tor apart is there any cheap mods or hop-ups i can do while im in there? performance wise? i wana keep this as cheap as i can.


thanks in advanced!
nick
 


Wow, you actually got one w/ blown HG's? Pretty rare on these motors. Probably bad LIM gaskets or a cracked UIM.

You could replace the UIM with the updated one, the stove pipe for the EGR, install an HV3 for better upper rpm performance. Other than that a top swap would be the next step, but you said cheap upgrades so that may be out.

Make sure you replace the LIM gaskets w/ the updated aluminum ones from GM or Fel-Pro and not the black plastic ones. Flush the coolant and either refill w/ Dexcool again, or change it completely to green coolant. Just don't mix the 2.
 
OP- before I forget and in case you aren't aware- the head bolts are TTY and cannot be reused, as are the rocker bolts.
 
yup it is definatly headgaskets, we used a block tester to test the cooling system for exhaust gases. or could exhaust gases leak by a bad LIM gasket? i mean the car dosnt blow any white smoke or anything like a blown headgasket should... so idk. but yah we have a full felpro gasket kit coming along with headbolts, didnt know you cant reuse the rocker bolts either?

where can i get the updated UIM? also what is a stove pipe for the egr? and whats an HV3, and a top swap (supercharger?)? im new to these 3.8's. i know a hell of a lot more about the LS V8 motors that are in the pickups lol still getting used to this 3.8.
 


The LIM is very common on these motors also the uim is fairly common to crack as well. I'd try that first before I pulled the heads off. But if you do pull the heads you could top swap it.
 
Cheap, Reliable, Quick.

You only get to choose 2 of the above.


If you've got the budget it would be a good time to topswap and cam, if not, leave it stock.
 
well when we tested the cooling system for exhaust gases the blue liquid turned yellow almost imediatly. so there was a lot of gasses in there, which is why i suspect a headgasket. plus coolant was boiling out the resovoir. even if it turns out not to be the headgaskest and is just one of the intakes, atleast i will know i have good headgaskets now lol i got the full top end gasket kit coming so i might as well replace all the gaskets.

i do not have the money to do a top swap, maybe down the road.. i think i will block of those coolant ports tho for good insurance.
 
so, got the whole top end and heads torn off the block, gonna clean it up and put it back together. we found a huge hole in the top of the upper intake manifold! lol gonna need to be replaced
 


any clue what caused this huge hole in the top of the manifold? could it be from the hot gasses of the egr tube blowing up at it?
 

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No but the Serries 3 motors have a metal UIM. You could upgrade to it if you wish, and never worry about those chinsy plastic one's again.

Junkyard to the rescue!
 


what does the wire harness look like above that area? my first guess would be electrical fire. or the previous owner drilled a hole there for something.... starting to make sense... Previous owner had nitrous on car and had a port there... blew the head gasket and sold the car
 
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