ZR-1 Net Registry Forums

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- C4 ZR-1 Technical Postings (http://zr1.net/forum/forumdisplay.php?f=9)

- - Dunn Heads (http://zr1.net/forum/showthread.php?t=7601)

Quote:

Originally Posted by Jeffvette (Post 52981)

Record Run car was red, not black and had Birmal, not Dunn heads. Enough said.

Quote:

Originally Posted by Hammer (Post 52576)

On the Net Registry site there is a section that has a list of all cars known to have Dunn Heads. Yours isn't on the list, but there could always be cars with them not listed.

I know that didn't answer your question, but I couldn't find that on the Registry. I know it's there.

My 95 (#378) definitely had both Dunn heads, and it is not on the list. There should be approximately 130 or so with the double dose of Dunn, but aren't all shown and the list has not been updated in ages.

Done heads ? Never heard of them :dontknow:

Was there a point, by either serial number or year, that the cars had both Dunn Heads? :dontknow:

Quote:

Originally Posted by Jeffvette (Post 52981)

Record Run car was red, not black and had Birmal, not Dunn heads. Enough said.

Just think how much faster the record would be if it did have Dunn heads :sign10: Not even enough said :wave:

Quote:

Originally Posted by JThomas (Post 87178)

Was there a point, by either serial number or year, that the cars had both Dunn Heads? :dontknow:

I think it had to do with using up the inventory of the Birmal heads and then using both Dunn heads.

Wow this post still isn't Dunn. :cheers:

love to see a "back to back" flow test and flow "quality" testing

alot of the machining and lessons learned on the tensioner were incorporated into the dunn heads and lots of folks think they added a bit o power.

both the early and late lt5s are a pretty stout animal. most of the 30 hp came from just a bit better cams, intake, manifolds, and yes probably just a bit from the heads

but keep in mind they were similar enough that quite a few LT5s went out the door with only 1 dunn head

hmmm......... so probably not so much difference huh??

the intake and injector housing definitely are different as the injector boss is much smaller. the early intake was originally designed for a larger injector than the multics, and the intake wasn't retooled when the injector changed until 93. look at them side by side and you see why porting the earlier intake picks up more than the 93 LT5 (oh by the way, there aren't any other LT5s other than 90-92 and 93 last of the beast LT5s were all made then HOTB is a great book!:razz:

My car is red, it has "dual" Dunn heads, and for these reasons alone no one has ever contested the fact that it is the fastest 1995 ZR-1 ever built. :cheers:

Think I have pics of the right & left:

My '95 shows Dunn # 10225121 & 10225122 as far as I can make out w/mirror & flashlite!! Production # 399 date on door 4/95 Any thoughts, theories confirmation or doubts?
Thanks