Head work

[Call_Me_crazy]

I have been looking into haveing the Heads from my 93 3.2 atx reworked at some local machine shops,some places wont even touch them. However of the places ive talked to and got estimates from i have gotten a range of prices from about 300.00 to 1000.00 for the just the heads, The car has 148,000 miles on it and had been sitting since 01. The heads are in decent shape and i dont think they will need mush work. What kind of things should I have done to them? The places i talked to said they would cleam them, make sure the valves seat right, pressure check them, and set the valve lash. One place told me they replace the shim to set the last another place told me they grind down the stem of the valve to set the lash, which is the best way? I need to get these things done and out of the way so i can get the motor back together give me your thought and suggestions please!

Heres some pics of the heads and the blown head gasket Sorry for such big pics!
REAR Head Gasket

Rear Head

Rear Head all three

Front Head

Front Cam Tensioner

Rear Head Top

 

[SHOtimer]

Wow, the inside of that motor is nasty. SHO heads usually do really well for long periods of time. Why did the head gasket blow? I would first check the heads for warpage - if they are warped too much you will need new ones - the SHO's heads have a very very small tolerance for being planed.

If they arn't warped too bad, I would have them planed (just to put a new surface on them) and pressure checked. They will probably turn out to be just fine. Then you can just put them back on.

When I rebuilt my motor - I just had the heads pressure checked and the valves vacuum checked - everything turned out to be fine (the heads I used has 132k on them). So, I had them planed a bit and the valve stem seals replaced. That is all I did to them and she runs great. Granted they weren't nearly as nasty on the inside as yours are - but that shouldn't affect much.

While you have it all apart - I would drop the oil pan and replace the rod bearings.

The right most combustion chamber on the second picture looks pretty torn up.....not sure if that should be reused or if you should look into what caused that problem.

Doug

 

[Whip]

all i can say is damn there is a hella lotta room for bigger valves in that baby!!!!.sorry for saying that but that is the first time i have ever had a chance to see a SHO head off of a motor. i bet with a little work and looking around i bet you can throw some bigger valves in the head. ( not sure if anybody had thought of that before maybe try to do a search for it but i bet it can be done at a resonable price. i have done bigger valves in my old 302 and i did them myself were as people said i could not do it . and yes i know a 302 head is different than a sho head but hey were there is a will there is a way!!!

 

[SHOtimer]

Some people have put in slightly bigger valves, but unless you are running boost it is worthless. The SHO heads already flow at a rate that can't really be improved much upon....unless you are really doing a lot.

Doug

 

[Whip]

why is it always worthless when it comes to doing things with the sho. all i see is people trying to get more power out of there car and all people do is post.well unless you do =x it aint worth it . i think that even if you get 5 hp gain it was worth it cause if you think about it 5 hp here 15 hp there it all adds up in the end . an i think there is room for improvement im gonna find me a set of 3.0 heads and do some playing around and see what i can come up with. i have access to a flow meter and i will make sure i do a dyno run before i install the heads !

 

[Sh03d]

Stock SHO heads will out flow the motor. They flow better then racing mustang heads. So giving bigger valves doesn't do much if you don't boost or cams.

For the price of machining and the valves the horsepower gain per dollar would be very small.

This is what I've heard and read.

 

[Whip]

ahh ok (sorry to get off topic on you call me crazy)so the heads out flow the motor so it would be better to spend the money on cams and motor work ?


edit edit call me crazy there is a set of 3.0 heads on e-bay cheap

front head :
http://cgi.ebay.com/ebaymotors/89-9...8054931692QQcategoryZ6763QQrdZ1QQcmdZViewItem

rear head :
http://cgi.ebay.com/ebaymotors/89-9...8054931962QQcategoryZ6763QQrdZ1QQcmdZViewItem


opps i just realized that you have a 3.2 motor sorry about that (but correct me if i am wrong wont 3.0 heads fit on a 3.2 and yo0u get better performance ?)

 

[naval-avi8or]

I know where to get a nice set of heads if you need them. Contact me at [email protected] if your interested.

 

[Sh03d]

ahh ok (sorry to get off topic on you call me crazy)so the heads out flow the motor so it would be better to spend the money on cams and motor work ?

opps i just realized that you have a 3.2 motor sorry about that (but correct me if i am wrong wont 3.0 heads fit on a 3.2 and yo0u get better performance ?)

My first comment wasn't accurate. The heads will flow more then the cams will allow.

1. The best thing is to open up the intake/exhaust, then gasket match to the heads if your not going all out. Motor work and cams will do more then just porting heads on stock engine.

2. 3.0 heads will not work on a 3.2 considering that the accessory mounting is different. And your thinking of 3.0 cams on 3.2. The intake cam is slightly more aggressive.

 

[Lorenr]

Head Gaskets

I'm surprised. With 150 K miles there really is not much wear on the cam drive tensioner.

The motor may just look dirty because of the photo.

Find out why the head gasket went. Check the block and check the head. Have a machine shop do it they will know what to do. It could just be a bad gasket and if you caught it in time, replacing it may be enough.

Install a new gasket using the best procedure and it will be OK.

If you must do the heads, take them a part AFTER checking valve lash. Check the valve lash first, that way when you reassemble them you will know where you are at. HAND lap the valves with lapping compound. Cleanse everything and put it back together. Recheck the lash when you are done. It should not move enough to require adjusting.

The valves do not look as though they are leaking.

 

[Mr Anonymous]

Buy another motor.

Buy another motor.

Buy another motor.

Or at least another set of heads.

You don't want to use those heads, plain and simple. Very few warped SHO heads can be brought true in the miniscule amount of decking allowed without causing other problems such as an intake that won't fit and higher compression. And honestly, from the appearance of the heads that car has had more than one oil change interval of 10000 miles plus, so the maintenance history wouldn't make me feel too good about the block either. It would be a shame to spend $1000+ to get the heads worked, new head gaskets, etc. only to have a bearing spin a couple thousand miles down the road.

Any machine shop that tells you that they can adjust the valve lash with the heads off the block shouldn't be allowed to touch them. The valves can only be adjusted accurately after the heads have been torqued to the block.

Used 3.2L motors can be found for around $400 just about anywhere in the country. Another couple hundred in basic maintenance (new seals, gaskets and such) and you've got a motor that should serve you well for another 100K miles before needing more maintenance. As mentioned, there is not a whole lot to be gained with head work on these motors, at least not without a lot of other more expensive mods.

 

[Off Road SHO]

Chris,

I agree with you. Buy another motor and freshen it up.

However, what you said about the valve lash has got me stumped. I can see where you wouldn't be able to set the lash in a pushrod motor where the cam is in the block and the valve actuators are in the head. But why would you not be able to adjust valve lash where the cam and actuators are bolted together? Am I missing something here?

Tom

 

[Call_Me_crazy]

The car sat for at least 4 years with nothing being done it, the oil in the car when I got it, is the oil you’re seeing in the pictures except for a quart of Lucas oil treatment. There was a 1/4" cake of old oil between the oil pick-up and the bottom of the pan. The motor is completely out of the car and in pieces waiting for me to clean them up and send them to the machine shop, I don’t think I need to get a new engine; the block is pretty good except for the rod bearings bring worn to the copper on the rod arm side. The motor was running very strong. With only a slight knock until it warmed up and the overheating caused by the blown head gasket. I have a feeling the gasket only blew because of being improperly torqued, but I may be wrong. The knock I am assuming was the cam tensioners being gummed up from all the rancid oil. I may be wrong on that to. But I think with a good cleaning and through check this block and heads will be ok. I think it will cost me just as much to fix the things wrong with this motor as it would if I got a different one and I already know what I have and that it truly ran instead of some junk yard motor that who knows what kind of **** its been through, It might cost $400.00, them my time to tear it down and it might be in a worse shape. In which case I am out $400.00 and some time and back in the same situation. **** I only paid $400.00 for the whole car! I budgeted about $3000.00 for the motor/tranny work so far I am only about $500.00 into it.

 

[LeddZepp8687]

If the heads arent warped, I would have the shop do a valve job, And port them and deck them a little to up the compression. just my $.02

 

[Whip]

ty sho3d i did not know that

 

[pjtoledo]

. .......Any machine shop that tells you that they can adjust the valve lash with the heads off the block shouldn't be allowed to touch them. The valves can only be adjusted accurately after the heads have been torqued to the block.

.............

If you can use torque plates on the block, why not on the head?
It would be interesting to see how much the lash changes.
Ok, the next few guys doing an engine bebuild, how about checking the lash before and after you pull the heads. And just for fun, throw in the cam bearing clearances.


Perry

 

[NotSoSlowSHO]

However, what you said about the valve lash has got me stumped. I can see where you wouldn't be able to set the lash in a pushrod motor where the cam is in the block and the valve actuators are in the head. But why would you not be able to adjust valve lash where the cam and actuators are bolted together? Am I missing something here?

Tom

Key words in Chis' response are "acurately" and "torqued"

Physically you CAN adjust the valve lash on a head that is not installed onto the block. But it is not advised. Why? Simple (yeah right) deflection of the heads.

 

[NotSoSlowSHO]

It would be interesting to see how much the lash changes.

Me too.

I wouldnt expect any measurable change on a head as burly as the SHO's, but I would never want to risk it doing my own rebuild.

And just for fun, throw in the cam bearing clearances.

Id expect more changes there than shim clearances

 

[Mr Anonymous]

The car sat for at least 4 years with nothing being done it, the oil in the car when I got it, is the oil you’re seeing in the pictures except for a quart of Lucas oil treatment. There was a 1/4" cake of old oil between the oil pick-up and the bottom of the pan. The motor is completely out of the car and in pieces waiting for me to clean them up and send them to the machine shop, I don’t think I need to get a new engine; the block is pretty good except for the rod bearings bring worn to the copper on the rod arm side. The motor was running very strong. With only a slight knock until it warmed up and the overheating caused by the blown head gasket. I have a feeling the gasket only blew because of being improperly torqued, but I may be wrong. The knock I am assuming was the cam tensioners being gummed up from all the rancid oil. I may be wrong on that to. But I think with a good cleaning and through check this block and heads will be ok. I think it will cost me just as much to fix the things wrong with this motor as it would if I got a different one and I already know what I have and that it truly ran instead of some junk yard motor that who knows what kind of **** its been through, It might cost $400.00, them my time to tear it down and it might be in a worse shape. In which case I am out $400.00 and some time and back in the same situation. **** I only paid $400.00 for the whole car! I budgeted about $3000.00 for the motor/tranny work so far I am only about $500.00 into it.

Yeah, but when a motor sits, the oil doesn't burn up in the top end like that; that's clearly from a consistent lack of maintenance plain and simple. Those heads are trash, cleaning may make them look pretty, but that's about it. Even if they were crystal clean, the warping makes them more valuable as scrap aluminum to me. The worn rod bearings are another indicator that this whole motor isn't worth putting a penny into, cause you'll just be paying to do it all over again not too far into the future.

FWIW, the warped heads weren't caused by a blown HG, it was the other way around (sort of). Your motor was overheated, warped the heads, which then caused the HG's to fail.

WRT to adjusting the valves with the heads off the block, yes tq plates would work technically, but I wouldn't trust doing it that way. No matter what you're going to want to check the lash once the heads are torqued to the block so why do it several times? Once is faster and simpler! We've had 2 or 3 customers bring in sets of heads which they described as "ready to go" on the block with the valves already adjusted. They still needed a number of shims once the heads were installed on the blocks. I don't know the physics of it, but have seen how it works in the real world.

In my ideal world, valves should be re-adjusted after 10 hours of operation any time the heads have been reinstalled.

 

[Jrodm12]

If you have shop air or a air can fill it. Put the spark plugs in. Put the heads upside down and put water into the combustion chamber. blow air into the intake ports and exhast. You shouldn't see bubbles if you do the vavle seat is leaking and will need to be replaced.