1969 302 DZ Heads

[Southerner]

Hi, this is my first post on this forum. I am restoring a 69 Camaro. The heads are 3927186 castings witha date code of J 11 8 and J 28 8. They are the big valve 2.02 and 1.6. Untouched and unported.What I want to know is, did the Z28 motors heads come with guideplates or without in stock form ? As these heads have no guideplates and the (I presume) press in studs.

The cylinder block that these heads came of is  casting 3932386 4 bolt block date code I 25 8 The build date of the 69 body is 12B.

So is it possible the early 69 camaro Z's came out with the non guideplate heads and the later model 69 Z's as the production progressed come out with the guideplate heads.

[Gambitt]

No 69 Z's came with guideplates.  There were also no screw in studs. 

[Southerner]

So what I have got here is some stock standard Z heads that came off that block then. Thats another question the block was cast on I 25 8 .....  25th Sept 1968 and the build date on the car is 12B.... 2nd week Dec 1968

[firstgenaddict]

I had mone machined for Screw-in studs (7/16) and guid plates... the 7/16 studs keep the valve train more stable.

[Southerner]

i would probably like to keep mine original. the body of the car is going to be the fun.....Oh boy. It has been in CA most of its life, But I have and will be replacing most outside panels.

[Jerry@CHP]

FYI,

Original 2.02 heads have an unshrouded polished area around the intake valve in the combustion chamber.  If that is not there, this could mean they were opened up at a local machine shop.  Most shops who open 1.94s to 202s do not have the proper eq to finish the job right.

Jerry

[68Zproject]

FYI,

Original 2.02 heads have an unshrouded polished area around the intake valve in the combustion chamber.  If that is not there, this could mean they were opened up at a local machine shop.  Most shops who open 1.94s to 202s do not have the proper eq to finish the job right.

Jerry

Jerry,

Do you do this service and/or have this equipment?

[Southerner]

Thanks Jerry, I will go have a look and send a pic. Mike

[Jerry@CHP]

My machine shop does.  They use a certi machine to do these conversions.  And you are better off starting with a 194 head.  The valves are always sunk too far in original 202 heads when you find them, building a new 202 head from a 194 valve head gives you a fresh factory type valve job.  DO NOT INSTALL HARDERED SEATS!!!!!

Jerry

[1968RSZ28]

DO NOT INSTALL HARDERED SEATS!!!!!

Jerry

Why Jerry?  

Paul

[JohnZ]

Because there's VERY little metal left between the valve seats on 2.02" heads as it is, and it's very easy for a shop not intimately familiar with these castings to go through into the water jacket when cutting the recess for the seat, at which point the heads are scrap. The seats are NOT necessary unless you're towing a trailer at 100mph all day long or the engine's going in a boat.

[Jerry@CHP]

Thanks for posting that John.  I couldn't have said it any better.

I am suppose to be getting a pair of heads later this month where a seat fell out and did a lot of damage to the valve and combustion chamber.  Another reason why not to install them.

Jerry

[68Zproject]

Thanks for posting that John.  I couldn't have said it any better.

I am suppose to be getting a pair of heads later this month where a seat fell out and did a lot of damage to the valve and combustion chamber.  Another reason why not to install them.

Jerry

I think I'll have you do mine.  I already have a Dz motor that's now worth about $10.00!

[firstgenaddict]

$10... just about anything can be fixed... even if she needs to be sleeved or cracks welded up... if the engine is original to the car you do whatcha gotta do.

[68Zproject]

Not original to the car, unrepairable crack at main #2.