Intake Manifold Porting Show ‘n Tell

[RevTheory]

So could we conclude that the Bowtie is still a pretty darn good single-plane?

[6.50camaro]

I have not done an in-depth study of the differences between the two. On the surface I have found 3 things different. 1] Carb pad height. the GM carb pad is .690" taller than the Hurricane. 2] the port openings as cast, GM 1.30 x 1.975 , Hurricane 1.18 x 2.125 . 3] in the plenum the GM is more open and what I Feel is a better path from the carb pad to the runner openings on the inner runner pairs, 3-5 4-6. There could be more small differences but these were what I noticed first. GM cast 1 intake and machined them different for the raised runner and std. height runner manifold. they both have 10051103 cast in the front . The std runner height manifold has machined flats at the top of the runners where the flange meets the heads and P/N 10051102 stamped in the machined area on the 2-4 runners.

[HQM383]

Port matching of #1 hp manifold





Top 5 horsepower results manifolds L to R. What are the design consistencies that make this progression of 1st to 5th logical? Same question for the top 5 torque line up where the manifold on far left is 1st, crap port match 2nd, AFR 3rd, Brodix 4th and Hurricane with black fittings 5th?



Something I’ve noticed visually with the Hurricanes

[WeingartnerRacing]

The version 1 hurricane has the least taper. Version 3 has more bend in the runner that the others don’t have. None of these are that close to the bow tie on the inside. Outside it might look that way. Version 3 is drastically different.

I’m editing video now and the video comparing the afr, Brodix and super victor may be out Sunday.

[HQM383]

The version 1 hurricane has the least taper. Version 3 has more bend in the runner that the others don’t have. None of these are that close to the bow tie on the inside. Outside it might look that way. Version 3 is drastically different.

I’m editing video now and the video comparing the afr, Brodix and super victor may be out Sunday.

Another curve ball. Looks can be deceiving. I’ll go back and look at the numbers in previous vids.

Keep up the great work Eric.

[Hilton]

I purchased my AFR heads back in 95 , The 220 version I asked what manifold do they recommend Because at the time they weren't making manifolds yet . They recommended the GM bowtie so I shipped it to them , They port matched it to the heads

[Bob Hollinshead]

[quote=WeingartnerRacing

The hurricane with the worst port match was number 1. That’s why we test.
[/quote]

How bad was the match? Both height and width issues? There really might be something unseen that happens there with a SHARP edge mismatch in that location. Would be an interesting test subject...We see odd things happen. People making mid 600hp numbers with peanut port heads and a mismatched oval port rpm intake. Rectangular intakes on oval port heads outperforming a matched intake. Stuff sometimes doesn't make sense

[juuhanaa]

Ive been thinking about how to port match this sucker and now you say just put it on the bench and see how much it flows...

IMG_20211130_194518__01.jpg

-juhana

[Tom68]

The hurricane with the worst port match was number 1. That’s why we test.

How bad was the match? Both height and width issues? There really might be something unseen that happens there with a SHARP edge mismatch in that location. Would be an interesting test subject...We see odd things happen. People making mid 600hp numbers with peanut port heads and a mismatched oval port rpm intake. Rectangular intakes on oval port heads outperforming a matched intake. Stuff sometimes doesn't make sense

The match it appears wasn't horrid, the workmanship and blend distance was.

[GARY C]

I purchased my AFR heads back in 95 , The 220 version I asked what manifold do they recommend Because at the time they weren't making manifolds yet . They recommended the GM bowtie so I shipped it to them , They port matched it to the heads

BES told me the same thing, the last one I ordered was actually their raised runner cut to fit a standard runner head, they told me they no longer cast the standard runner version.

[brentry]

If I understood Eric correctly, he used a 1” open spacer on the performer rpm and the AFR tapered 4 hole spacer on the AFR dual plane and everything else. I wonder if the AFR dual plane would have picked up any with the 1” open spacer.

That's how I understood it.
That afr spacer on the flowbench is clearly worse on the afr duel plane. I happen to have that spacer , bought it with intake 3 months ago .A spacer that looks like the intake works well or open not bad, Or a shorter center, tapered spacer maybe worth a try,Tried 5 spacers.

20230218_141827.jpg

[Dave B]

Some tunnel ram rework for sons dragster, wanting to run some 4.30s this year

IMG_20230121_155550981.jpg

[skinny z]

If I understood Eric correctly, he used a 1” open spacer on the performer rpm and the AFR tapered 4 hole spacer on the AFR dual plane and everything else. I wonder if the AFR dual plane would have picked up any with the 1” open spacer.

That's how I understood it.
That afr spacer on the flowbench is clearly worse on the afr duel plane. I happen to have that spacer , bought it with intake 3 months ago .A spacer that looks like the intake works well or open not bad, Or a shorter center, tapered spacer maybe worth a try,Tried 5 spacers. 20230218_141827.jpg

Is it a fair comment to say the AFR dual plane and the Edelbrock RPM Air Gap are pretty much the same? From outside appearances, it looks to be that way.
My understanding is that the popular and apparently most effective spacer on a dual plane is a 1" open version. At least on the Performer style of manifold.
I would have liked to have seen that combination (AFR intake and 1" spacer) tested as well.

[brentry]

Haven't seen a air gap in person in awhile.
But I do know the carb pad is a little different I think . I wouldn't assume a open is best. One showed is good.
A short taper is good. Of corse I tried a Open.

[RevTheory]

I've got this 2 inch Wilson going on an RPM Air Gap under a Terminator X Stealth. I dunno...

IMG_0363.jpg

IMG_0360.JPG