[lust4speed]

Got an engine in and owner says he has Kaufman 290 CFM heads. Pulled off the intake and found that the previous builder used a set of FelPro 1233's on the previous build but sure didn't have to.

Did the 290's come with a standard sized port or RAIV sized port? Thinking these might be the "as cast" heads?

[JLMounce]

Definitely the same sized ports as my as cast KRE D's. I don't necessarily know if that means it's not a 290 head, but I purchased the same gaskets when I first installed them, not realizing they are standard port size, not RAIV sized.

[lust4speed]

I have photos of Kaufman 310 CFM ports that we've installed and photos of as-cast, but haven't done any 290's. Just seems like they would be the larger port, and wondering if the previous shop didn't give the owner what he paid for. Too late now, but would be interesting to know for sure.

[JLMounce]

What do the port walls look like?

My as cast units have the sand cast texture right up to the port entrance where there's a very slight amount of clean-up milling. If it's a 290 head it will have CNC tool marks in the port.

[Gastiresandoil]

I think the Intake ports are a little different for Kauffman heads than cast heads.

[JLMounce]

Dang, I got gipped on my KRE's. They don't look anything like that!

[johnta1]

That's the CNC option on the D-port heads.

[steve25]

Ah, the cross pollination of two motors!

[Stroker467TransAm]

So, what size are the as cast intake ports? Is there size difference between say a as cast size and say a 310cfm port size? Thanks

[Steve C.]

The KRE D-port "310 CFM" cylinder head would use the SCE 128103 head gasket that has a port opening that is 1.170 x 2.320. Due note unless recently changed SCE printed material is incorrect in their reported size for that specific gasket. I've been using it for years on all my heads with 2.300" tall ports and it is 2.320" tall. Also Dave Bisschop notes it here:

http://www.sdperformance.com/viewPro...productID=1788

The Felpro 1233 gasket commonly termed as the RAIV gasket is about 1.180 x 2.200

Dave Bisschop states his KRE 295cfm heads require Felpro intake gasket # 1233 or equivalent.


.

[JLMounce]

Originally Posted by Stroker467TransAm

So, what size are the as cast intake ports? Is there size difference between say a as cast size and say a 310cfm port size? Thanks

As cast ports will be standard D port size, NOT RAIV.

That said, I've been running RAIV gaskets for 4 years without issue. Probably leaving a bit of power on the table, but the car still performs well.

I'm doing some top-end maintenance this spring that will include properly sized gaskets. I'm not really expecting anything performance wise from it.

[Steve C.]

Side note... the gaskets I mentioned above in post #10 were not specifically for the "as cast" standard KRE D-port head. As mentioned here some sources suggest the RAIV gasket. This said I believe I've seen Cliff Ruggles post he has used the regular MS90205 that is about 1.125 x 2.062 on the stock KRE head. hopefully he will correct me here if that is incorrect.

https://www.summitracing.com/parts/fel-ms90205

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[Half-Inch Stud]

Are you people saying KRE 290 CFM happens with a Ram Air III Port size?

[Steve C.]

"The KRE D-port head is a well designed head for street/strip applications. We start with a raw as cast KRE D-port head and CNC port it to flow 290-295cfm @ .550"..."

That from the SD Performance website. More in the link about the intake gasket...

http://www.sdperformance.com/listPro...?categoryID=49

Side note: More often than not in the past info I've read suggests the as cast KRE D-port head was reported to flow 260 cfm. But not sure at what valve lift that was rated at.

Here 261 cfm at .500"
https://www.hotrod.com/articles/0501...-dyno-results/

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[Half-Inch Stud]

Okay, so SD Perf says 295 CFM KRE gets the 1233 = 90123 = RA IV port.

[lust4speed]

Guess I should post a better close up photo of the ports in question. I'm with the thinking that as-cast Kaufman's were standard port size and anything from 290 CFM on up would go to the RAIV size or even larger in the 325+ ports. Since the port doesn't come close to filling out the FelPro 1233's I'm going with these are definitely as-cast heads. Included is another photo showing that only a very quick gasket match was done to the heads.

[firechicken]

Those look as cast to me.
These are SD 290s

[slowbird]

Originally Posted by lust4speed

Guess I should post a better close up photo of the ports in question. I'm with the thinking that as-cast Kaufman's were standard port size and anything from 290 CFM on up would go to the RAIV size or even larger in the 325+ ports. Since the port doesn't come close to filling out the FelPro 1233's I'm going with these are definitely as-cast heads. Included is another photo showing that only a very quick gasket match was done to the heads.

Interesting the first inch or so appears to be cnc'd but after that appears to be as cast.

[pastry_chef]

Originally Posted by Steve C.

Here 261 cfm at .500"
https://www.hotrod.com/articles/0501...-dyno-results/

That articles flow for the KRE look off at mid lift values.

In Oct 2004 these were values provided direct from KRE.

lift I Ex
.100 90 70
.200 164 130
.300 224 165
.400 257 197
.500 265 218


Stan provides a few examples here, other people flowing the stock KRE get very different numbers.
http://users.erols.com/srweiss/tablehdc.htm#Pontiac

from Paul Carter.
KRE D-port heads, exhaust opened to 1.77" valve. Bowl blend to blend valve job, and a port match to stock Fel-Pro intake gasket

Originally Posted by gtofreek

Here's the head flow numbers.

Lift_____In/Ex
.100" = 79.5/71
.150" = 118.2/103.4
.200" = 156/125.6
.250" = 185.6/142.1
.300" = 205.9/155.5
.350" = 226.8/172.8
.400" = 247.1/180.8
.450" = 258.9/188.8
.500" = 264.5/194
.550" = 262/198.4
.600" = 262/201.6
.650" = 264.5/204.8
.700" = 264.5/208
.750" = 263.9/209.6
.800" = 264.5/211.2

[Steve C.]

It appears those flow numbers in the Hot Rod article came from KRE. Manufacture and type of flow bench used make a difference in reported numbers. KRE at one time did not use a SuperFlow test bench on their cylinder heads. Unless they changed types. Years ago it was a J.K.M. flow bench. The JKM uses an averaging velocity tube to measure flow.

.