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Masive knocking noise and spark plug all oily



Kinda sounds like a valve train noise. Which you could get those symptoms from say a valve opening or not.

Which uh..piston was the one that you replaced with an L36 rod/piston?
 
I would stop messing with the frankensteined motor and get a complete L36 bottom end for a couple hundred bucks and swap it in there. What was your reasoning for using one GTP piston and rod?
 


Don't mean to be that guy...

but I called it.

Using different compression pistons, especially with smaller pulleys and no tune isn't going to do anything good for you either.

I tried explaining it to you as well, and I'm with Joey...go buy a COMPLETE short block. LOW compression. STOCK supercharger pulley. I'm sure if you refreshed the rebuild with all new gaskets...it would last thousands upon thousands of miles.
 
you need a whole bottom end, hows the head look? any damage to it?

and a used engine with 130,000 + miles on it aint that bad in the 3800 world. your going to freshen it all up anyways like every gasket you can while its out. cheap insurance.
 
It has nothing to do with diferent pistons . Their the same. But anyways i took apart that engine i had on te ground and its all scrap soo yep great.
 


guimond47 said:
It has nothing to do with diferent pistons . Their the same. But anyways i took apart that engine i had on te ground and its all scrap soo yep great.
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Lol umm yea cyl 3 has a gtp connecting rod and piston. Lol its a gtp bottom end wit 5 l36 pistons in it lol
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Seriously?? It has nothing to do with different pistons??? Please remove short block, use it as a coffee table, and part the rest out.

Of COURSE it has EVERYTHING to do with putting the WRONG piston in!!
 
considering the L67 pistons and rods are just physically COMPLETELY different.... so different hellen keller would have no problems telling you which one was a L67 piston/rod.

The L36 rods are also much longer, so if you were somehow able to get a piston pin into a L36 rod you would have like 12-1 compression.
 
guimond47 said:
Dude they all have same compression and pistons look all eexacly the same
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They are FAR from the same.

L36 pistons have 9.4:1 compression
L67 pistons have 8.5:1 compression

The crank is balanced for ALL SIX rods/pistons to be the same weight/dimensions.

You have FIVE of them making 9.4:1 and ONE making 8.5:1...on what...a stock GTP tune? All those cylinder temps...Lolololz.

Trolled?
 
Just from common sense, wouldn't the NA piston have a higher compression ratio anyway? Most forced induction engines have very low NA compression ratios as they get compression from the induction systems.

The other thing I would be worried about, aside from the difference in compression, is the difference in weight. I would recommend to anyone who does this sort of thing, to weigh each piston, rod, wristpin etc so you have a balanced rotating assy.

I agree with the others - get a used shortblock.
 


oops lol oh well . now i have my 3 front cyls gtp and my rears are gt lmfao..... well see how it runs boys lol ill let youse know ! all i gotta do now is to hoook up the harness and away we go. what makes em hare more compression ratio ? the connecting rod or the piston itself.
 
guimond47 said:
oops lol oh well . now i have my 3 front cyls gtp and my rears are gt lmfao..... well see how it runs boys lol ill let youse know ! all i gotta do now is to hoook up the harness and away we go. what makes em hare more compression ratio ? the connecting rod or the piston itself.
Click to expand...

DO not even bother to finish this engine, remove it now and install an engine that is know to be in good shape. Your just making more work for yourself, and throwing money out the window by "frankenstiening" engines.
Also, put the stock superhcharger pulley back on.
 
What can possibly go wrong tho lol stupid question but like i been running two different pistons for a while and they always ran like a normal engine, never had ruff idle or anything soo please explain wat can happend thanks
 
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