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Discussion Starter · #1 ·
Is it possible to change the heads without pulling the engine? Sorry if it's a newb question, I've just never done it before on the GTP. Thanks in advance
 

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I did mine, I had the engine out though...
Its defionitely possible with the engine in the car though.

As for basic instructions, the Haynes or Chiltons manual was a help for me along with some other stuff I had. They don't usualy cover the supercharged engines in thos books, but the head instructions are generaly the same as N/A motors... (order of procedures, torque patterns and values...etc)
Dont expect anything spectacular with those books, but if you're handy with a wrench its all you need.

I'm not sure why youre going to do it, I'd recomend using ARP hardware for the new heads though, the torque to yield stuff is junk IMO.
 

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Discussion Starter · #6 ·
I'm not sure why youre going to do it, I'd recomend using ARP hardware for the new heads though, the torque to yield stuff is junk IMO.
More than likely I am going to upgrade heads in the near future. I am planning on adding 1.7's to my VS cam. Another question: Will heads alone (without rockers) improve my cam performance from stock? Forgive my ignorance, but what is torque to yield?

does anyone have instructions or a writeup for him?
I think this is what he is looking for and many others would like as well
A write up would be outstanding if there is one. I checked on tacgp.com but they didn't have anything like that. Thanks again.
 

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torque to yield bolts, otherwise labeled TTY, actually have a fraction of the tensil stregth of ARPs bolts and likewise. Instead of installing TTY with a nice and easy, say 50lbs of torque, you actually get to do some geometry w/ angles. If i remember correctly, the heads went something like, 25 lbs to each bolt in pattern, 270 degrees to all bolts in pattern, then 90, then 45 or some rediculous **** like that. the bolts LITERALLY stretch out in the middle. some say they are weak... some say it doesnt matter. im one to think, use them ONCE and ONLY once and you'll be fine each time.
 

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KillerGTP said:
More than likely I am going to upgrade heads in the near future. I am planning on adding 1.7's to my VS cam. Another question: Will heads alone (without rockers) improve my cam performance from stock? Forgive my ignorance, but what is torque to yield?

A write up would be outstanding if there is one. I checked on tacgp.com but they didn't have anything like that. Thanks again.
Along with what Jonathan said, dont re-use TTY hardware. This would include the head bolts and rocker arm bolts in your case, also the main bearing cap bolts and the flex plate hardware...

As for upgrading the heads, I did my own, take a look at my mod link to see pictures (not a write up, but its all I have).
In a nutshell, what I did was to remove all the sharp edges in the combustion chamber and open up the exhaust ports by getting rid of the "knife-edge" to smoth out the flow into the headers and minimize the hot spots and turbulence. I also did complete rebuild and valve job with new exhaust valves, LS1 springs and new valve seals...
As for it being worth it, I run a 3.1" pulley with zero KR.

Granted, aftermarket heads would be nice, but if you got the time, all it takes is some simple hand tools to make thinks that much better.
 

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Discussion Starter · #9 ·
Thanks for the responses. I'm sure I'll be ok, though are there any common mistakes that people make with doing a job like this? You know, just any thing to watch out for? I plan on taking tons of pics and staying organized so I dont jack up the reinstall.
 

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Common problems I can think of are.....putting head gaskets on wrong (wrong side, upside-down) Keep track of aaaaaaall your bolts since you'll be removing, the alt., power steering pump, front/rear manifold, coil bracket, intake manifold, SC, fuel rail, rockers, and pushrods. Torquing the heads at the correct ft/lbs and bolting sequence are VERY importaint.
 

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I agree with seen96.

Also, as the job progresses you'll probably go from cleaning the bulk of the dirt off with a can of spray parts cleaner and a stiff brush to a thorough cleaning after the valves are lapped and any metal modificationas are done to remove lapping compund and metal filings... etc prior to assembly.

A big tub of HOT soapy water is the next best thing to hot-tanking. (Dawn really does get grease out of the way) The heads should remain submersed while the scrubbing is done. If they are exposed to air they will rust quickly.
A quick rinse with HOT water and an imediate, continuous blast of compressed air dry towles with a can of WD-40 in hand to pickle the iron immediately is a must.
A laundry tub/utility sink works great. I attached a short hose to the fawcet for rinsing.

If you don't dry the irion immediately and oil it, the rust will ruin the head gasket surface and your valve seats/lap job.

Of course you'll need to wipe the WD-40 off with alcohol or parts cleaner right before gaskets are applied.
 
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