I have 100,000 miles on my 96 LT1 and have future plans for a forged/blueprinted 355/383 PTK turbo project. My cam specs will not be revving past 6,200 (for valvetrain reference) However i will not have enough money to buy heads for a while on this project.
My question: I need my heads rebulit for as cheap as possible to get them in good working order.
1. is it easy tro rebuild heads yourself?
2. What machine work is absolutley necessary?
3. i'd like to do most of the work myself.
i know i need at least new springs.
Any thoughts/advice would be great.
Thanks, tony

 

well, if you're going to be making some power, then I'd opt to get the bowls and chambers ported,and polished. but for machine work, you're going to want the heads magnafluxed (crackcheck), milled for flat/square surfacing, 3 angle valve job, seat pressure check, and ofcourse cleaning the headsthuroughly. my local machineshop charged meabout $280 to do allof what i listed (besides porting),as well as disassembly and reassembly. it's almost not worth assembling and disassembling them yourself. they will install new springs upon request for no extra labor fee. I'm guessing your not going to be doing the machine work, so I'd just let the shop have them.

 

I just rebuilt my heads and machined them. I work in a machine shop so i did everything myself. Basically, i would get them cleaned (obviously) and then just get the basic machine work done. It's not that much work for the machine shop if you take the heads apart yourself and put them back together. If you do take them apart yourself, make sure that you have the valves checked, cut, and cleaned. Alot of times the valves that come out aren't in that great of condition. If i was you i would just buy new valves.
The springs are usually fine. Also, the machine shop should do this but make sure that the guides are checked and whatnot.

 

Thanks for the reply guys... Does anybody know people in the san diego area that can do work like this? Sounds like I'll be buying springs and valves plus the machine work. No porting necessary on these heads... ported afrs are in future plans.
Anybody else have expereince with rebuilding lt1 heads?
Thanks for the input fellas
-Tony

 

Basically just get them off the car, take 'em apart and keep things organized and together. Sandwich baggies work well. If your valves arent hurt, then you can reuse them, but I would recommend swapping the springs out for a fresh set. Springs definately have a finite life, and @ 100K miles, your stockers have probably had it. Also, when you disassemble the heads, have a a piece of emory cloth (a girls wooden nail file works fine) handy. This is to take off any burrs on the valve stems from the locks. The locks tend to pinch the tops of the receiver grooves, and it "crowns" out a little on the sides of the valves. Just hit the high spots with the emory board or cloth to knock them down flat before dropping the valve through the guide. This'll keep you from scoring the valve guides, and will help with oil control.

When you have the heads done at the machine shop, have em cleaned up, checked for flatness (might need to be milled flat a little - pretty common with aluminum castings), and have the machine shop assemble them (unless your comfortable with doing it). Don't bother asking to have them magnafluxed, because you can't magnaflux aluminum. That only works on metals that can be magnetized. You can have them LPI checked (liquid penetrant inspection), but unless you suspect or have had problems, then I wouldn't bother. Just have them setup the heads for you (as in make sure the valves are cut right for the seats, etc..), and go bolt them on and go. Also, don't cheap out on good stem seals. Go with viton seals, as nothing is more of a pain than to have to go back and change the seals out later (with the heads on the car, it's a serious PITA!). All that and a good quality gasket (factory GM is fine) and you'll be good to go...

Good luck man..

Dave C.

 

Actually, i have iron heads on ,my block.. so i guess it can be magnafluxed. I ave a book on rebuilding LT1/LT4 engines, so that should be helpfull on disasembling heads properly with out incurring damage to them.
Thanks for the response... Now i need to find some cheap new valves, springs, and seals...any suggestions guys???

 

If you're really looking to go budget, just have a shop check for flatness (and cracks if you're not sure about the condition), have the seats done, and get the stock valves lapped to the seats. If you have a valve spring compressor, assembly isn't very difficult at all. Get some new seals with your new springs. I had a valve job done on a set of iron heads, a magnaflux and a flatness check, all for $125. I did the disassembly and reassembly myself.