I have a 1986 Ford F-250 6.9 L turbo, i would lie to rebuild the engine at some point, i would like to run a turbo at 20 pounds of boost what woud i hve to change out and about how much would this cost.

 

What turbo do you have now?
Do you want to reuse it?

Are you going to do the work yourself or hire it done?

 

Head bolts have to change. ARP head studs are ~$250 for the set.

Pistons should probably also drop some compression. For that you have 2 options.

1, is to replace the pistons with aftermarket pistons that are intended for engines that have been resurfaced on the deck. These pistons drop the top by about 10 thou if I remember right and don't cost any more than the stock 22.5:1 CR pistons. A paid about $250 for a set of new pistons with pregapped rings already installed. Thinking back it was a steal (canadian dollars too).

2, is to have your pistons shaved off from the top to drop the compression ratio. I did this with my truck and took 20 thou off them. Found a back yard machinist that my auto machine shop recommended and he did all 8 for $75 cash.

None of the turbo kits you find are intended to give you 20 PSI of boost since normally a 6.9 can't take that without problems. Whatever kit you have, it will need modding to make that kind of boost and you may also have to uprade your fuel system since you will likely run out of fuel at 14 psi with a stock injector pump maxed out.

The only performance injector pump that I would recommend costs $700 and up.

Mods for a turbocharger could involve replacing the compressor side and the turbine side and you are probably looking at ~300 per side. Avoid later banks turbo kits since they are based on the more expensive mitsubishi turbocharger, and the ATS 088 has a proprietary turbine side that can't be swapped out.

As Dave eluded to.....what is your budget?

 

well it is my only form of transporatation so i cant' spend forever with it not running but i would like t do it myself. The turbo is i believe an ATS My budget is around 2,500 to 3,000 to rebuild the engine and all the rest that goes with it. If anyone has rebuilt this motor please give me some advice.

 

I think you better save money for a bit longer. Your going to be short of funds at $3,000 for what you want to do.

I have not done it but I know what the costs are for parts and machine work.

 

ok one thing i have been wondering the 83 and 84 blocks have a 20.7:1 compression, so if you find one thats has a good block and put all new gaskets in it and stud the heads intake and exaust manifolds you should be able to get 20-25 lbs boost right? in diesel power they had a salt flat racer that also daily driver the makes 22-25 lbs of boost on a 22.5:1 compression ratio and the heads are still on,

 

Im fine sticking with a stock turbo with lower boost thats low priority just, i wounld like to keep many parts as possible, possibly refurbish the heads if they are good, the rods, new cylinder heads. but im not sure what all i will have to replace until that time comes, i just not sure how much i will need to have saved for a project like this

 

You should plan on a minimum bore, just enough to have fresh cylinder wall surfaces.
20 over is the smallest oversized piston available.

So a set of pistons and rings are in order.

Heads, rebuild unless there is a problem.
7.3 turbo valves have a better metal for turbo motors, they drop right in.
While you have it apart, 7.3 rockers are much better and stronger.
Check valve guides, replace as required.
Check valve spring tension, replace as required.
Replace the valve stem seals, they are included in the master engine rebuild gasket set.

Replace the cam and lifters.
Replace all bearings and seals.
Felpro gaskets.

Head studs are better, even with stock boost levels.

When you remove the injectors, wet tips indicate leaking injectors, so keep that in mind.
If it is in the budget, I would install new injectors.

If you can do all of the labor yourself, you will be cutting it very close with 3000 dollars.
Can you get the engine block and heads to a machine shop after it is pulled and disassembled?

I had my block and heads magnafluxed before I did anything.
I also had the crank checked and polished while it was apart.

If you use head studs, boost up close to 20 PSI should be no problem.
Over 20 PSI, you better mill the pistons and you will have to do some work to the intake so it don't blow the valley pan/intake gaskets.