missmatched ports

[motorheadted]

My Weber intake manifold ports were port matched to the taller 428 intake sizes before i got it some years ago, and I ported my E-bock heads to match the intake on the 1st re-build.
I am now rebuilding it again with a different set of  E-boks with the mid-rise int port sizes which are less tall than  the 428 size, closer to the mid rise 427 size (engine is 427)  and I was wondering if anyone here had ever made a port smaller using an epoxy  ( JB Weld) as opposed to welding build-up & re-grind to size . ??


Ted .

[bill_396]

I believe they make specialized epoxy based products just for that purpose. My intake has had the floor of the port opening brought up about 1/4" if I'm remembering correctly.

[blykins]

Do the port roofs line up?

[Joe-JDC]

If the roof and sides match well, then I wouldn't worry about it.  Every time I blend the floor of a MR head to the CJ port floor, they lose flow on the flow bench.  Joe-JDC

[motorheadted]

All good info, Thanks Guys !!

[Falcon67]

NOT JB WELD

Use Splash Zone Compound - found usually at boat repair stores.  Works even with methanol (for a while LOL).  It's what is typically used to re-shape ports, stick port tongues in 351C 4V heads, re-shape ports in billet Jr Dragster engines, etc.

Also same - if the roof and sides line up well enough, run it.

[motorheadted]

i've found a couple of products  that would work; An A-B type sold by Moroso and Edelbrock and a Devcon product.
 However, based on Joe-JDC and Brents experiences, I'll try doing without trying to match the floor. I have a previous dyno sheet to compare the mismatch intake affect on performance
The roof and sides are OK.


Ted

[bill_396]

Just to be clear, do you have dam or a waterfall condition?  Waterfall okay, dam, don't think so.

[My427stang]

Dam on the bottom doesn’t hurt, bulk of the flow is running along the long side (roof and sides)

[6667fan]

Could be worse. You could be trying to stick an intake with medium riser ports on these heads.
That is a Mr. Gasket 202 A medium riser gasket laying there.

[blykins]

You need some Cometic intake gaskets and then trim if necessary.

[6667fan]

Exactly.
Blair is hooking me up with something that is .060 thick and no ports are cut out, just water passage and bolt holes. I still have to be mindful of how close to Barry’s port I try to get size wise. The limiting factor is my Dove TW does not have abundant material around every port.
I realize I don’t need to match them from a flow standpoint. I’m after a better seal than I had with the 1247-S3 that were last on engine.