86L or 86E
Le Mans Master
Joined: Mar 2006
Posts: 5,262
Likes: 0
From: E. Amherst NY
86L has Aluminum heads. Aluminum heads have the center-bolt valve covers. The iron heads have traditional SBC perimeter bolt valve covers. Most, if not all roadsters have the Aluminum heads. I say most because I'm pretty sure its all roadsters, but I could be wrong.
Team Owner
Joined: Dec 1999
Posts: 34,873
Likes: 487
From: Lacey WA RVN 68-69
NCM Sinkhole Donor
The last approximately 8600 coupes are believed to have had the aluminum heads installed. This is the VIN number range for the coupes:
1G1YY078XG5100001 - 1G1YY078XG5127794 If your car has the factory aluminum heads, the last 5 digits of your VIN should be higher than 19194.
If you have a 'vert, they all have aluminum heads.
1G1YY078XG5100001 - 1G1YY078XG5127794 If your car has the factory aluminum heads, the last 5 digits of your VIN should be higher than 19194.
If you have a 'vert, they all have aluminum heads.
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Le Mans Master
Joined: Jun 2006
Posts: 5,642
Likes: 5
From: One day you're a Comet...the next day you're dust... Arkansas
Le Mans Master
Joined: Dec 2002
Posts: 5,270
Likes: 3
From: Seattle Area WA
It is nothing I would lose sleep over. I believe the difference was 5hp. So, big whoop. If you are going to do anything to the heads you might as well go to zz4 (113s, 88+ Vette heads) or aftermarket. I don't think the difference is really appreciable unless you start modding at which point, they both would probably be quick to go.
Instructor
Joined: Jul 2007
Posts: 222
Likes: 0
From: Toronto(Don Mills) Ontario
It is nothing I would lose sleep over. I believe the difference was 5hp. So, big whoop. If you are going to do anything to the heads you might as well go to zz4 (113s, 88+ Vette heads) or aftermarket. I don't think the difference is really appreciable unless you start modding at which point, they both would probably be quick to go.
Le Mans Master
Joined: Sep 2006
Posts: 6,050
Likes: 147
From: Phoenix AZ
2021 C4 of the Year - Modified Finalist
heads
If you decide to go with the factory aluminum heads, remember they are 58cc, and you don't have dished pistons. I have an 86e, and I put those heads on it, and if I nail it from a stop, the computer pulls the timing way back because the knock sensor tells the computer that it's pinging.
I have to build a few revs first, then nail it, and it just flat goes.
With the higher compression, my mileage readout at 75, flat and level is right at 33-35 miles per gallon.
It was 28-29 before I swapped them out. average is 23 mpg on the daily drive with 135,000 miles on the clock.
I used 89 injectors, and 88 TPI setup.
The later rocker cover/head combination are almost totally leak free as well.
I am building a 383 for it, and I got 14 cc dished pistons, and wafer thin head gaskets and the 113 heads.
you would be better off with a set of vortec heads that are drilled for both styles of intakes. That way, you could get a later Scroggin -Dickey manifold at your convenience, and it would fit like a glove.
Chris
I have to build a few revs first, then nail it, and it just flat goes.
With the higher compression, my mileage readout at 75, flat and level is right at 33-35 miles per gallon.
It was 28-29 before I swapped them out. average is 23 mpg on the daily drive with 135,000 miles on the clock.
I used 89 injectors, and 88 TPI setup.
The later rocker cover/head combination are almost totally leak free as well.
I am building a 383 for it, and I got 14 cc dished pistons, and wafer thin head gaskets and the 113 heads.
you would be better off with a set of vortec heads that are drilled for both styles of intakes. That way, you could get a later Scroggin -Dickey manifold at your convenience, and it would fit like a glove.
Chris