[grandam1979]

Well not really port work more the lack of. This is the 69 intake I just had blasted it was definitely a little worse than most.

[PAUL K]

Wow..... I know if that was a reproduction intake manifold a bunch of folks would get a worked up over that.

[steve25]

Go look up into #8 runner at the crap that needs to come out below the bolt boss.

[b-man]

And it didn’t affect how it ran.

I purchased a ‘71 455 HO intake back in the early ’90s and of course it looked much worse than that iron intake and much like the current repros, it’s not like it slowed those cars down and made them run like turds.

People get too worked up about these things, some intake to head port mismatch doesn’t really matter much if at all on your average street engine.

[Stan Weiss]

Originally Posted by grandam1979

Well not really port work more the lack of. This is the 69 intake I just had blasted it was definitely a little worse than most.

Does all 4 pair of ports look like this?

If so do all of the larger ports match up to the same manifold "H"?

Stan

[J.C.you]

Originally Posted by grandam1979

Well not really port work more the lack of. This is the 69 intake I just had blasted it was definitely a little worse than most.

Night shift Saturday night? Or Monday morning? Hehe

[mgarblik]

Originally Posted by b-man

And it didn’t affect how it ran.

I purchased a ‘71 455 HO intake back in the early ’90s and of course it looked much worse than that iron intake and much like the current repros, it’s not like it slowed those cars down and made them run like turds.

People get too worked up about these things, some intake to head port mismatch doesn’t really matter much if at all on your average street engine.

Yikes! That must be the manifold The Parts Place used to create their reproduction! I have to disagree some with B-man on that one though. As bad as that intake is I bet you would see an average HP loss of 5-7 HP and 10-12 at peak rpm. Would love to do a back to back dyno pull to verify. True the average new car owner would probably never know the difference but it would be there.

When I worked at the Pontiac dealer we would of course take the new cars out and run the crap out of them during PDI's. I remember distinctly identical cars running quite a bit different from each other. It all depended on whether the engine was built more or less closely to the engineers design specs. or just barely within tolerance like that manifold which probably should have been rejected, melted down and re-poured. (Must have just made it through inspection at 4:55 PM on a Friday)

[Skip Fix]

My SR 72 HO intake I bought in '79 was a little off but not that much. My factory intake on my 78 TA original motor was almost a perfect match-of course I tossed it when I got the HO intake
And in high school we tossed a 409 block that could have been sleeved that now guys would pay $1500-2000 for !

[grandam1979]

It’s definitely worse than most I have had but it doesn’t take long to clean it up to a stock gasket. The pictures are 3 different ports I should have put all 4 but the one was actually pretty good.

[android 211]

Way back Car Craft did a before and after port match dyno test and picked up 3 hp. I had a '72 cast iron intake with a huge glob of slag inside the #8 port. It was as big as your thumb nail. I got it off a junk yard car so someone drove around like that for 20+ years.

[steve25]

If the manifold flange exit is even a 1/16” smaller then the head that’s not a issue, but you do not want a mismatch the other way.

[242177P]

Had a 69 intake with a thin chunk of casting flash, around the size of a nickel, obstructing one port. Only needed a light tap with a hammer to remove most of it.

[Steve C.]

Google....

Is intake manifold port matching worth it?

You will get dozens of responses, and the same amount of opinions on the subject !

Here is one....

"On the surface, this would appear to be an important part of any high performance engine build.
This would seem especially important when the intake port opening is smaller than the manifold.
This is even supported by flow bench testing where any obstruction or sharp edge at the port inlet results in major flow losses."

"But this is one situation where the flow bench can lie to you."

Source, and more here:

https://www.onallcylinders.com/2016/...0flow%20losses.


And here a discussion we had on PY....

https://forums.maxperformanceinc.com...d.php?t=815791


.

[PAUL K]

Originally Posted by Steve C.

Google....

Is intake manifold port matching worth it?

You will get dozens of responses, and the same amount of opinions on the subject !




.

Oh christ! Google


I think it depends ..... a lot

I know of one case it would've made a significant difference. Your old 600 HP factory block build with the Torker 2.

[Steve C.]

Paul mentioned my previous 600 hp 462cid combo.

During the dyno session we tested a Holley Street Dominator intake that was worked by Dave Bisschop with a 1/2" open spacer and it made 589.4 hp at 5600 RPM.
The Victor was also tested with a 1/2" open spacer, it made 600.9 HP at 6000 rpm.
Then we tested a borrowed Torker II intake that was unmodified and not port matched to my heads and it made 566.7 hp at 5600 RPM.

My cylinder head ports were about 2.300" tall. My intakes are always port matched to the cylinder heads in use along with runner blending.

If that TT2 intake was properly port matched and runners blended would it have had better results?

Google won't help there

.

[TA63]

The 72 intake I just port matched looked just like that on one side. The other side was nearly perfect.

[mgarblik]

What we don't see in any articles I have read through is' "port matching the intake to the heads will hurt HP and Torque". If you are paying someone to do this work on a street car and they want $ 200.00 to do it. Then it may not be "worth it" for a couple HP on a street engine that may not see 4000 RPM. That's why the factory didn't do it and the lousy looking one in this thread made it on a factory engine. But if you are doing the work yourself, a chance to pick up say 5 HP for free is appealing. Labor is yours and making 5 extra HP for a couple hours work on a really bad intake is worth it to most hot rodders. Find 5 HP in 10 places on a blueprinted engine build and you have 50 extra HP when it's all done. We do this every class day at school. The little things add up, the gains don't all come in one place. That's why every engine we dyno, even with stock heads, stock cams, intake, carb and exhaust manifolds always make very close to factory rated HP or a little more. Last year a student did a regular 400 Pontiac for a GTO restoration. Rated at 350 HP. Everything stock, right to the cam and rocker arms. It made 377 HP @ 451 ft. lbs torque

[steve25]

Also please note that if the exit on the intake runner happens to width wise be less it 100% not a issue as long as it’s not more of a mismatch then the amount that the push rod budge sticks out into the head.
This can save you a good amount of unnecessary work at times.

[J.C.you]

Originally Posted by mgarblik

What we don't see in any articles I have read through is' "port matching the intake to the heads will hurt HP and Torque". If you are paying someone to do this work on a street car and they want $ 200.00 to do it. Then it may not be "worth it" for a couple HP on a street engine that may not see 4000 RPM. That's why the factory didn't do it and the lousy looking one in this thread made it on a factory engine. But if you are doing the work yourself, a chance to pick up say 5 HP for free is appealing. Labor is yours and making 5 extra HP for a couple hours work on a really bad intake is worth it to most hot rodders. Find 5 HP in 10 places on a blueprinted engine build and you have 50 extra HP when it's all done. We do this every class day at school. The little things add up, the gains don't all come in one place. That's why every engine we dyno, even with stock heads, stock cams, intake, carb and exhaust manifolds always make very close to factory rated HP or a little more. Last year a student did a regular 400 Pontiac for a GTO restoration. Rated at 350 HP. Everything stock, right to the cam and rocker arms. It made 377 HP @ 451 ft. lbs torque

Makes the case for flow testing heads with intake and carb attached. Be sure to tape all runners at the flange except the one pulling from.

[Formulajones]

Originally Posted by grandam1979

Well not really port work more the lack of. This is the 69 intake I just had blasted it was definitely a little worse than most.

Thanks for posting that. Like Ive said in other posts, OEM iron and aluminum intakes are like this, some more than others, and no one ever says a damn thing about it, but the minute you have a repop like this the whole world is collapsing LOL

Like mentioned not that big of a deal. Touch it up if its bothersome. Or run with it. The engines ran fine 55 years ago.