Re: PSMCDR...new "tech"
 

Well, while I was looking up blueprint info over at NHRA.com ( http://www.nhra.com/tech_specs/engine/ ), I looked at what they had listed for the L-78/L-89 option. They show 2 aluminum heads, casting #s 842 & 401, in 1968 & 1969, their valve sizes are 2.195/1.845, and they were available only on the Camaro. Now, I know this shouldn't be taken as "the gospel truth", but that is what the NHRA shows.

Re: PSMCDR...new "tech"
 

The Pure Stock Drag Racing group has decided to stick with their original plan of a prerace tech. I tried to explain that I thought it would be much easier/safer if the cars could be assembled at home, after a post race tech, but to no avail. The cars will be teched the day before the event. Tom

Re: PSMCDR...new "tech"
 

Also, the date for the PSMCDR has been pushed back a week, from the 6th to the 13th.

Also, I have heard rumors that there will be a '70 COPO Nova that will also be participating in the "certified stock" tech...

Re: PSMCDR...new "tech"
 

Ray,

Good information on the aluminum heads. All of the closed chamber aluminum heads that I have seen on production cars have been either 392s (67 L-89/L-88) or 842s (68-69 L-89/68-early 69 L-88). That 838 is a mystery to me, as is the 387 that I mentioned in my previous post. Looks like this one is going to take a little more research.

I took a look at the information on the NHRA site. The 401 head they have listed is probably a later model service replacement (I notice that they list this head for the ZL-1 as well - almost has to be an open chamber head if that is the case). A quick check through the current GM Performance Parts catalog would probably identify this head. The 077 listed for the L-88 and ZL-1 is most definitely a service replacement head that was never used on a production car.

Tom,

Sorry to hear about the decision that Dan and Bob made. Logistics may have played a part in that, but I still think that doing the teardown afterwards is the way to go. It's their show though... And a darn good one at that!

Regards,

Stan

Re: PSMCDR...new "tech"
 

Ray and others interested,

3919838 turns out to be an early PART number for the closed chamber aluminum head with CASTING number 3919842. I think that this number may have been revised at a later date to reflect the casting number, but 838 is listed as a part number @ 1975.

Still checking on 387 and 401...

Regards,

Stan

Re: PSMCDR...new "tech"
 

Stan - I have a listing with the part no. 838 as a alu. " Head, cylinder, w/valve guide" and part no. 072 as the second design alu. head.

Re: PSMCDR...new "tech"
 

Joe,

Thanks for the confirmation. Yes, what you show is correct - part number 838 is casting number 842; part number 072 is casting number 074. Again, these part numbers are from the mid 1970s and may have been superceded, but they are correct at that point in time.

Now, anyone know something about the other two? I'm beginning to think that the 387 that shows as a casting number may actually be a part number for the 392 head - just a theory at this point. Can't find any reference to the 401 head. The search continues...

Regards,

Stan

Re: PSMCDR...new "tech"
 

So, will there be any other Supercars @ the PSMCDR this year?

M: will your's be ready? I heard Sipmson might bring his '70 COPO Nova down for the certified stock class.

Rob

[Edited by sYc (11-02-2000 at 03:36 PM).]

Re: PSMCDR...new "tech"
 

The 401 heads are listed on a web page. Check out: http://www.mortec.com/bbc.htm

They list two different heads with the 401 suffix, 3935401 & 12363401. There is more good information on this site for both BB & SB Chevrolets.

Stan & Joe, Thanks for the help in identifying the 838 heads.