Corroded P90 Head (I am F*ck*d) NEED HELP!

[Ben's Z]

I just talked to my machine shop. A few day ago they said there were some corroded spots on the head (on the deck and around the thermostat) so they tig welded some of the spots up. I just called for an update and they said that when checking it they could easily poke holes into some of the water jackets by the valve springs in the head because the head was ate up from by anti freeze management by previous owners of the car. Has anyone heard of such a thing?

 

Now what should I do? I can't use any other N/A head with the 280zx turbo can I with the stock ecu?

 

I am mentioned it 1000 times but my mods were going to be RRFPR, intercooler, exhaust and raised boost to 11 psi or so using the stock injectors, turbo, ecu etc.

 

This really sucks.

[Ben's Z]

Can I use a p79?

[Ben's Z]

From Tony D at zcars.com Taken verbatim.

 

ANY Datsun engine can be TURBOCHARGED WITHOUT CHANGING THE PISTONS.

 

Jeebus guys, SHUT UP ABOUT DISHED PISTONS!

 

SniperX is ABSOLUTELY CORRECT! At 7psi the 'lower compression' does NOT even REMOTELY come into the picture.

 

As for SniperX being used to 'MAP Based Vehicles' I'd suggest you search on "Megasquirt" and use THAT as your ECU right from the get-go on the conversion. They are available for $400 from a number of sources, and give you full adjustability.

 

Matter of fact, I'd say with stock turbo injectors in the block and a Megasquirt, you will easily be able to run 10-12psi of boost on your conversion without an Intercooler simply because you can douse the cylinders in extra fuel to compensate for the lack od density.

 

Having had a NON-DISH TOP N/A conversion for 23 years, and putting 40K+ miles on it running normal boost at 12psi, and up to 21psi (WITHOUT DISH TOPS) it just maddens me when PARROTS spout and confuse people.

 

IF YOU DON'T KNOW, SHUT UP!

 

ARGH!

[NewZed]

As I understand it, the only significant difference between the P90 and the P79 is the exhaust liners. And the cam. Your ECU won't be able to tell the difference if you swap the P90 cam over. The downside is that there is a possibility of a liner breaking free and ending up in your turbo.

 

If you use one of the other heads, you'll need to do more tuning. Notice that Tony D used Megasquirt on his flat-top turbo setup.

 

No actual experience from me, just knowledge picked up from the forums.

 

The water jacket corrosion is fairly common on cars run with straight water. Anti-freeze is loaded with corrosion inhibitors.

[Zmanco]

P79 and P90 have the same combustion chambers. Difference is that the P79 has round exhaust ports and exhaust liners. While I haven't seen anyone replace a P90 with a P79, don't see why you couldn't. The ports won't match up the best to the exhaust manifold, but if it's that or leave the engine in pieces, I'd go for it.

 

I don't know how the liners would hold up on a turbo motor - maybe someone can speak to that from experience.

 

That said, people post P90 heads for sale here pretty often, so unless you're in a rush, you might want to source a P90, especially if you're going to pour some money into rebuilding it.

[BluDestiny]

You could easily source a P90 or a P79. Just put a wanted add up. P79 will be cheaper. I believe I sold my last p79 for $60 or $80. But yes watch out for the exhaust liners breaking off. I do know 1 person running a turbo p79 at the moment with no ill effects.

[Sparky]

I have a bare p90 I'd let go of, send me a pm.

[Ben's Z]

I have a bare p90 I'd let go of, send me a pm.

Box is full

[Sparky]

Huh, shouldn't be let me clear some stuff out. When I get home. Basically looking for 70 plus shipping obo for the bare head. I'll send you something when my box is clean.