CPI Head casting #'s

[87wildside]

I want the CPI heads for my TBI. Anyone know the casting numbers for the CPI heads or have a link?

[1993blazerlt]

http://www.s10planet.com/forum/showthread.php?t=77

here is a little bit of info

[Tink]

92 & 93 1st design with 8 degree top angle CPI
10238181
10077626
14099064
10240209 This number is repeated under 94-95 I don't know why

94 & 95 2nd design with 30 degree top angle CPI
10238181
10240209
12522751

[87wildside]

What is the 8 degree/ 30 degree top angle? I would assume I need the 92/93 heads or will any of them work?

[Tink]

In '92 and '93, they came with an 8° top angle on the intake seat and a 75° throat, but that was changed to a 30° top angle with an 80° throat in '94.

[87wildside]

Well I found a reman set cheap, wating on casting numbers, but will any of the CPI heads work? I'll post the numbers when he sends them.

[Tink]

From the info I gathered on it...

1992-'93 truck with CFI and balance shaft: When the high output VIN "W" engine with central fuel injection was introduced in '92, the heads were redesigned for the application. They had eyebrows added to the top of the intake ports to make room for the injector nozzles, so the intake surface above the ports was increased by 0.250" for improved sealing, and the cast ledge above it was narrowed down to 0.350" to provide more room for the intake manifold.

The 10077626, 14099064, 10240209 or 10238181 castings were used, but be sure to check them over carefully because there are two versions of the 10238181 and 10240209 castings with an important difference. In '92 and '93, they came with an 8° top angle on the intake seat and a 75° throat, but that was changed to a 30° top angle with an 80° throat in '94. Separate the 8° heads from the 30° heads and use them only on the '92 and '93 engines.

Tonawanda switched to "net lash" rockers in '92, so some of these are adjustable and some aren't.

1993 truck with TBI, except heavy duty: The intake manifold on the TBI motor was modified in '93 to take advantage of the wider intake surface that was machined on the '92 and up heads, so these engines must have the heads with the wide intake and should use the castings with the 8° top angle on the intake seat.

1994-'95 truck with TBI or CFI, except heavy duty: The top angle for the intake seat was changed from 8° to 30° and the throat was opened up from 75° to 80° to give a 10% increase in intake airflow for better performance in '94. The same heads were used on both the TBI and CFI engines through '95.

Both the 10238181 and 10240209 castings were used, but they have to be visually sorted because the early ones with the 8° seat probably shouldn't be used on the '94s and '95s. If you do decide to stretch the rules and use the '93 heads on a '94-'95 engine, be sure to use them in pairs.
http://www.marineandstreetmotorsport.com/marineandstreet/wp-content/uploads/2007/07/seat-angles.gif



So, it might depend on the year of your block...

[87wildside]

I have a '90 block and the Edelbrock intake.

When I read ^^that^^ my brain just shuts off, don't know why. I guess I'm a frame and body guy...haha

[JONGO8]

Did you get the heads yet??

[87wildside]

I never got the casting numbers from the guy selling them. I'm just sending mine out to get rebuilt.