[455-4+1]

Jim, great effort

What do you think the durability of that much epoxy would be in a race application other than drag racing ?? (or in drag racing)

ie a 60 second 6000rpm full throttle run in a sprint boat ??

Do you forsee any problems with the intergity of the structure of the head long term (whats left of it !!!)

I realise its a pretty common practice to use for re-shaping etc but have not seen it used to that extent before. (have seen pics of the old Mopar 340TA castings "raised and brazed" by Mullins and Co prior to the W2 head coming out)

We have an intake flange X-section restriction of a Felpro 1206 gasket (Chevy rule) opening (1.34"X2.21" or 2.9614sq/inches) We have to meet this X-section maximum area (area but not dimension with our Pontiac)

I am currently running the 1233 (1.18"X2.20" or 2.596sq/inches) with that height we would be restricted to just over 1.3" wide at the manifold face to maximise the width within the CSA rule

[Skip Fix]

One of my buddies has a circle track SBC/Buick head that chunks of the epoxy came out of the intake port.

[Jim Robertson]

455-4+1,
We have plenty of faith in the material to stand up to the hostile environment in which we have placed it. Or I would not have done this. Surface prep is absolutely critical to get the adhesion and to seal the water jacket. I guess we will find out just how long it lasts and if my work was good enough.

No, not worried about structural integrity of head. Plenty remains in important locations and reinforcement bars tie rocker bosses back together.


Skip,
We too have heard of lost epoxy. A friend applied Moroso ab epoxy to the bowl of a super stock intake port. The engine (EFI Super stock manifold on the website) was "torn down" by NHRA techs at its first division race and some epoxy was found missing. Engine ran the same with and without but it did not meet the intake port volume rule so he was bounced. No damage to engine was found from the epoxy "passin' through." All work was redone with better stuff. He did not have any trouble after that.

We did not use Moroso AB on my engine...and it was applied to the outside of the ports.

[J.C.you]

i have used the moroso AB in several apps. This intake has had the AB in it for approx. 10 yrs. It has started flaking where it is thin around the runner entrances alittle. I used Splash Zone to reinforce these areas, but have not blended yet. I will spray a clear coat paint over the entire turtle after blending.

Jim, I have a gustram 2.470x1.440 runner entrance, with single lid if you would like to try it before i modify it for another application.

[Jim Robertson]

J.C.you,
Thanks for the offer. It certainly would have been cheaper to try the gutsram...but that runner entrance is sooooo big. It would take a big boy head to make it sing. I don't think I have near enough :-)

How's the Punisher testing?

Thanks again for the offer,
Jim

[J.C.you]

i will be using the carbon fiber and the gutsram on back to back comparisons in around a month hopefully.

[Jack Gifford]

Originally Posted by pontiac jack

Jim- Do you think (or perhaps know) whether that 127% VE suffers much without 30" header extensions? Thanks.

If the answer to this is 'guarded', I'll understand- I was just trying to learn a little something.

[Jim Robertson]

pontiac jack,
I apologize for not replying. I meant to last night. The collector extensions were installed for two reasons. The car will need about that length to get to my planned exhaust "dump" location...and to reach the dyno exhaust "system" which is 12" diameter flex pipe thru the wall. Our decisions were no more scientific than that. My intent was to test the engine in as close to the race configuration as possible. So to answer the question I do not know for sure but I do believe the VE could be affected but not by more than a percent or 2.

I believe the intake port size, shape, length and taper angle along with cam timing was the main reason for the VE number. The "sound" of the air flowing through the intake port was substantially quieter than other Pontiac heads we have had on the bench. When we cranked the bench pressure to 40" instead of 28" it was still very smooth and quiet...it flowed 427cfm at .700 valve lift. Next time you test your heads or have them tested, try to be there and take note of the sound. The smoother and quieter the better. FYI I have not ever got the Eheads to be anywhere near this smooth/quiet nor flow 427 at 40". I wonder what Kaase's heads "sounded" like on the bench. :-)

Jim

[Skip Fix]

Neat heads Jim and alot of thought out work!

[scott70]

I went with some 325 cfm e heads(which should hit the dyno in a couple of weeks)because I thought they were about the best things going for a race type head but after all the e head slammin',I'm starting to wonder.

[Skip Fix]

Scott-I'd bet even Jim here would admit getting the flow where he is and you are is a whole lot more cost effective starting with E heads. Jim did these for a particular project and his shop time is his own time. As he said 300+ hours of shop time on these, assume that is at an even cheap $20/hr that's $6K in labor! If the epoxy leaks water it's on his own motor not a customers that can hydraulic a cylinder.

Look at all the majority highest HP Pontiac motors before the Tiger or the KRE High Ports that are just now on the market. They almost all use Edelbrock heads,many wide ports, few using Wentzlers that take ALOT of work to get there. The main slamming I've seen is "the port is too big"-Jim's iron head is there also!

I'd bet some would like to see a cast iron intake cut,epoxied and welded for these heads, would be neat for a "stock appearing" motor but I doubt they'd keep up with 300 cfm of the head.

I'd go on but I don't want to hijack this thread over the amazing job he has done on these. I'd love to see them in action.

[fasteddy]

Here are some pictures of my D ports. These have no epoxy, no push rods moved and are not opened up to RAIV on the intake ports. They flow in the high 290s. The ports are slightly trapezoidal with the floor and short turn being wider than the runner roof. Borrowed from AMC design-sort of.

[scott70]

Yes,its very impressive,if you could get a stock " looking" intake on it that could keep up with the heads,it would make a hell of a sleeper.And I dont want to hijack either but one more ques,if the e head chamber was copied off the ra4 design,and a ra4 head may only need 32 degrees of timing,why is the e head chamber engine need usually 38 degrees and the chamber design not liked?My former 62 heads only wanted 30- 31 degrees.Edelbrock didnt come up with their own chamber design,did they?

[Skip Fix]

E heads have a generic chamber not related to any pontiac chamber. RAIV/HO/SD are a more open chamber than D port head chambers with the machine cut further back unshrouding the valves all around.

Fasteddy-no doubt yours flow well over where they started but I'd bet Jim's ports flow more than 10 cfm difference on the same bench. I doubt the pushrod movement, tubed head bolt, epoxy raised roof acount for only a 10 cfm increase. I'd bet he'd have taken 290 without all the extra to get the size that big. I don't know of too many Pontiac porters that get 290cfm out of ports smaller than RAIVs.

The SBC Vortec and old 409s also use a trapezoid shaped port.

[J.C.you]

flow numbers are nice to talk about, but i have seen 330 cfm ls1 heads that are a dog on the dyno. bolt on another set of 330 cfm heads properly ported and will make 100 more hp.

what i am gettin at is, it ain't all the same apples when you compare peak flow bench numbers.

[potentpontiac]

Your absolutely right on big flowing heads.You must try and maintain good #S on the lower lift area,say from 400 lift and up.It's all about port efficiency.Jim really took the extra step in obtaining #S that are virtually unheard of especially for D Ports.As Skip indicated,these heads that Jim did are for his personal use.How could you charge a customer for 300 hours of time and effort to acomplish these kind of #S.Still a great acheivement for him to do this project.

[scott70]

Originally Posted by potentpontiac

Your absolutely right on big flowing heads.You must try and maintain good #S on the lower lift area,say from 400 lift and up.It's all about port efficiency.Jim really took the extra step in obtaining #S that are virtually unheard of especially for D Ports.As Skip indicated,these heads that Jim did are for his personal use.How could you charge a customer for 300 hours of time and effort to acomplish these kind of #S.Still a great acheivement for him to do this project.

So are you saying it would be better to have a 325cfm head flow its max at .600 lift or .750 lift?I see some heads flow a max of 325 but thats all in at .600 lift and some others flow 325 but arent flowing that til .750 lift.Which would be better?
Skip.I didnt know that the e head chamber wasnt copied from a pon tiac head,I thought it was.

[BruceWilkie]

So are you saying it would be better to have a 325cfm head flow its max at .600 lift or .750 lift?I see some heads flow a max of 325 but thats all in at .600 lift and some others flow 325 but arent flowing that til .750 lift.Which would be better?
Skip.I didnt know that the e head chamber wasnt copied from a pon tiac head,I thought it was.

Engine displacement, RPM range, and cam profile will determine the better of the two. If you can get it at lower lift it makes it easier to cam properly due to mechanical limits.

[potentpontiac]

Absolutely the cam lift and other components play a significant role in cylinder head flow.#S are simply that.If your head flows big at 750 lift and has poor low lift #S and the cam is say 630 net lift,then the head will not coincide with the cam selected.It's important to maintain a good flowing port throughout the lift range,up to the point of where the cam net lift is.I think Jim's D-port exemplifies a port that is strong throughout the lift range,and his horsepower achievents prove the point.Combination is everything to create the ultimate package.

[scott70]

What would you consider poor low lift flow #'s on a head that flows a maximum 325 cfm?At .200,.300,.400???