anyone make aftermarket heads for these?

[no_doz]

i really doubt it, but ive noticed that the heads on the early 90's 3.4 quad cams almost always go bad & i was just wondering if any of you happen to know why, & also if anyone knows of any aftermarket heads that would work on these because the stock ones seem to be very unreliable. thanks guys,

ND

[bszopi]

No, they don't exist.

How can a chunk of aluminum be unreliable? What you you mean they almost always go bad? I don't think I have ever heard of a head going bad.

[ez112]

Yes please elaborate on what happens to these, and how.

[SappySE107]

No doubt cause I have had plenty of heads pass through my garage that weren't cracked or bad. Valve guides have dropped some inthe head but not fallen through (I think 4 guides out of a lot of heads, over 20). Warpage is always an issue for a rebuild.

[Husky]

Iono. I mean, mine haven't given me any real problems, I had a set with an estimated 200,000 miles, the valve guides were all wierd, but other than that they were fine, and it only took a few minutes with my press to get the guides back where they go. They were barely warped too, the machinist said they didn't even need to be surfaced. Now, the DSM head that I've got, it warps away from the block on a regular basis, It's shitty. Genuinely shitty.

[no_doz]

i dunno either, all i know is most of the time when i go to purchase a eurosport or z34 with the 3.4l quadcam-the heads are bad on them. i was told that my oil pump went bad on mine, so maybe its that part that goes bad on each, i dunno but how would i go about fixing it & preventing it from happening?

[bszopi]

Maybe you are confused... Maybe it is the head gasket that is bad, not the head.

[tijuana_no]

i lost compression on all cyliders ,in one of my heads with under 96,000 miles.
i don't know what happen just spit & spatter ,and gone.

[no_doz]

i had one of these cars &the head on mine oveheated & warped, it definitely wasnt the headgasket, but i suspect the oil pump... i dunno though, all of the ones around here have warped heads but i wouldnt think would all be because of that?

[napatiger]

I think that the Heads can be starved of oil very easy.

Look at the bearing install on the oil pump shaft/cam, the bearings hole is offset like 30 degrees or something, my first rebuild fryed my cam carrier from no oil. Next rebuild saw the bearing lined up with the oil passage.

[Husky]

See, that's different no_doz. First off, almost any engine will warp the heads if allowed to overheat, some just require more heat than others to warp the head. Second, a warped head is honestly no big deal. When I did my headgaskets as preventative maintenance this spring, I had the heads planed and they were a tiny bit warped, but since these are a non-interference motor with a (relatively) huge service limit for warpage, compared to the other engines I work on, you can get them planed down until they're not warped. And that's not particularly expensive, I had mine planed down true, cleaned up really good, had the valves taken out and cleaned, then had the valve seats lapped for 60 bucks for the pair of heads.

In short: No, no one makes aftermarket heads. Several companies rebuild factory heads, but that's about it. I've yet to see a non-reparable head for an LQ1, and frankly I have no clue what the hell you're talking about with unreliable heads and whatnot. Buy the car, fix the headGASKET, have the heads planed, and run it.

[FieroRush]

i had one of these cars &the head on mine oveheated & warped, it definitely wasnt the headgasket, but i suspect the oil pump... i dunno though, all of the ones around here have warped heads but i wouldnt think would all be because of that?

the head didnt overheat, the engine did. and thats your fault, not to be blamed a bad cylinder head. and the oil pump would not cause the engine to overheat.

I think that the Heads can be starved of oil very easy.

have you seen the size of the 60* 3.4 oil pump? that fucker could sustain a 7.0l ls7.

[napatiger]

I don't question the capacity of the pump, just the oiling distribution system.

Have you installed the bearings on the oil pump drive cam (so-called dummy cam)?

[Husky]

This thread makes me laugh.

[no_doz]

its not my fault when the damn oil pump just goes the hell out of it. i checked my oil right before i left & it was good, the oil pump ceased to pump oil to the head, causing it to heat up & warp. then again i guess it is my fault, my crystal ball is broken...