Author Topic: Intake manifolds  (Read 2787 times)

Offline old cars

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Intake manifolds
« on: April 18, 2022, 10:14:26 AM »

Offline Cliff Ruggles

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Re: Intake manifolds
« Reply #1 on: April 19, 2022, 02:00:08 AM »
Is there a point to be made here?

Googling up the efforts of others is at least 2nd or 3rd hand information.  Makes for nice reading but 474cid and over 525hp and up near 600 ft lbs torque is getting into the arena where we need to move a LOT of air to keep up.

I'll add here that a third party (I supplied the Q-jet for it) duplicated that engine build and used a "modified" Pontiac 455 HO intake.  It was not on the same dyno and the engine had a little more compression, but the same 290cfm heads and 236/245/112 "Old Faithful" camshaft. 

That engine made 554hp/604tq, or more power than all the intakes Dave tested on his nearly identical engine build. 

I've dyno'd all the 455's built here and when we want bragging rights number we finish the testing with a Torker II topped with a 1" spacer and at least an 850cfm carburetor.  They will always make more power from 4500rpm on up to peak HP. 

That set-up more times than not doesn't run as quick in the same vehicle at the track (gives up to much on the starting line, 60') but will typically run 1-2 mph faster on top end.........FWIW.......Cliff

Offline Mudsport96

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Re: Intake manifolds
« Reply #2 on: April 23, 2022, 04:31:24 AM »
Some time ago i found numbers on a ported and unported chevy iron manifold. And numbers on ported/unported performer rpm. And the ported iron manifold was just as good as the rpm. Albeit heavier, so maybe get a factory aluminum one from the 80s. But for a chevy making under 500 i wouldnt go to an aftermarket part.

https://cliffshighperformance.com/simplemachinesforum/index.php/topic,3260.msg14163.html#msg14163

Offline Cliff Ruggles

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Re: Intake manifolds
« Reply #3 on: April 23, 2022, 04:45:00 AM »
Way back when I tested my Pontiac iron intake against the RPM the folks at the dyno facility were shocked when the RPM made less power.  An RPM intake on at least 90 percent of the SBC builds I see wouldn't bring anything to the table in terms of improved vehicle performance.  Very few are at or much over 1hp/CID.  The place to spend money on SBC build are the heads.  So many excellent offerings out there these days that it surprises me folks still spend time/funds on "smog" era factory iron heads that don't flow for chit after you put tons of work and money into them.  They also don't take advantage of the excellent combustion chamber offerings.

A high percentage get "vortec" heads, simply because they are dirt cheap.  Then they have to buy an aftermarket intake, and they really need set-up for screw in studs.  No provision for an exhaust crossover either, so a horrible choice for your 4 x 4 truck engine that will need to plow snow next Winter.........FWIW........

Offline old cars

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Re: Intake manifolds
« Reply #4 on: April 24, 2022, 05:15:33 AM »
Some time ago i found numbers on a ported and unported chevy iron manifold. And numbers on ported/unported performer rpm. And the ported iron manifold was just as good as the rpm. Albeit heavier, so maybe get a factory aluminum one from the 80s. But for a chevy making under 500 i wouldnt go to an aftermarket part.

https://cliffshighperformance.com/simplemachinesforum/index.php/topic,3260.msg14163.html#msg14163

You Failed to mention the factory SBC intake manifold ported are numbers after 30 hours of porting by a competent person ( David Vizard ) who has much more experience with building SB and BB chevys than the people on this forum.
This type of porting would cost well above and beyond the price of a good aftermarket intake manifold that would equal the results.
Those results as reported by David Vizard also resulted in a 26 HP gain on a motor starting with some 300 hp.
That doesn't say much for those old SBC intake manifolds.

Offline Cliff Ruggles

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Re: Intake manifolds
« Reply #5 on: April 24, 2022, 12:18:01 PM »
There really isn't that much material to work with porting a factory intake manifold.  The biggest gains are going to come from opening up the plenum areas under the carb to the same apprx size/shape as an Edelbrock Performer or Performer RPM.

I "modified" my Pontiac iron intake is stages, doing the plenum areas first, drag strip tested it, spent some time at the openings at the intake gaskets, tested it again, then worked the runners a bit, tested it once again.  After all the work was done and verified the best possible drag strip runs I put it on the dyno, then did back to back testing against a half dozen aftermarket intakes.

I followed that testing with adding spacers to it, and spacers to several of the aftermarket intakes as well.

Decades prior I did the same thing with the factory iron intake sitting on the SBC in my 1965 Chevy II Nova race car.  That old iron intake, pretty sure it was a 1969 from a 350/300hp engine ran quicker than the older Edelbrock Performer intake I'd been using for quite some time.

I'll add here that when I tested, dyno and track the WORST intake of all of them was the Edelbrock Torker 1.  What a complete POS that intake is.  My modified iron intake outran it by 59 HP on the dyno.  Yes, not a typo, 59 HP!

The best intake on the dyno to date has been the Torker II with a 1" spacer.  It's a "turd" without a spacer but if you want bragging rights for peak dyno numbers get one.  It still didn't outrun my iron intake back to back at the track.  It was off quite a bit w/o a spacer and even with one and topped with my Holley 4781-2 850 DP carb it ran a tad slower in ET even though it ran a little higher in MPH.......

Offline Cliff Ruggles

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Re: Intake manifolds
« Reply #6 on: April 24, 2022, 12:32:25 PM »
I'll add one more thing here, this is specifically for Old Cars.

When you get time please do some testing of your own.  Google searching the efforts of others just doesn't cut it for me.  It's at least 2nd had information, you weren't there when the testing was done, nor did you have any input or help with any of the parts that were tested.  If the magazines had anything to do with it they are EXTREMELY bias anyhow (ask me how I know that sometime).

From almost the first day I got into this hobby I NEVER fell into that BS put out by the magazines about how great all this aftermarket stuff is.  Sure I ran out and bought Holley carbs, Mallory dual point distributors, and Tarantula intakes like everyone else did, but they SLOWED my car down at the track, didn't make it faster.  Even the Crane Fireball cam I put in the 440 powering my 1970 Roadrunner cut the nuts right off of it.  So I decided to start testing parts.  I've tested truck loads of intakes, spacers, distributors, bug zapping coils, modules, camshafts, torque converters, air cleaner assemblies, air cleaner lids,  spark plugs, headers, and cylinder heads.  Even did the HPP and Engine Masters articles about 20 years ago which included dyno runs and backed it up a few days later at a private track rental. 

So I'm more one to actually test a part vs Googling around and seeing how it did for someone else........Cliff


Offline old cars

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Re: Intake manifolds
« Reply #7 on: April 25, 2022, 01:47:52 AM »
interesting how you say you replicated the plenum of an Edelbrock . I don' get my information by google nor am I referring to intake manifolds from the seventies.
Anyone who says " I've tested truck loads of intakes" is when I stop listening.

Offline Cliff Ruggles

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Re: Intake manifolds
« Reply #8 on: April 25, 2022, 02:25:11 AM »
Well then.......where are the results of YOUR testing?

Since you don't want to listen, then you can not learn anything except for what you "google".  You mentioned at least once that you don't race your car......so tell me how do you learn what works and what doesn't?  Do you just believe that everything Dave Vizard says is gospel?

I have some DIRECT examples from customers who tried his cam recommendations and absolutely HATED the end result.  104LSA with the ICL clear down at 100 produced nothing but a "turd" and they couldn't amputate those cams out of their engines quick enough.

I used to buy into all that BS about aftermarket intakes, distributors, camshafts, etc.  Then I decided to start testing them to see how much more power we could make on the dyno and quicker our cars would run at the track.

I also street tested the parts as well.  This is when I discovered that "seat of the pants" testing is next to USELESS and some of these parts really pack some punch in a higher or narrower RPM range.  Since we "feel" transition or going from making less power to quickly making more, or like a shot of NOS, we very quickly evaluate this as an improvement compared to smooth strong power over a broader RPM range.  So transition very quickly fools the "butt meter" into thinking we have improved vehicle performance.

So how do you know aftermarket intakes outrun factory ones? 

How do you know tight LSA works better than wide LSA in street and street/strip engines?

How do you know those JUNK accl pump seals you boasted a while back are better than the ones I sell?

I'm all ears?

PS:  I did some over the last 30 days.  I put a NAPA blue pump seal, a NAPA black pump seal and my accl pump seal in a metal container with 93 octane 10 percent ethanol fuel from BP.  Early this morning I removed the seals and took the pic below.  My seal is on the right, the two NAPA seals, including the "black" one you mentioned being as good as the seal I sell here.  The two NAPA seals (Walker products origin) woln't even stay on an accl pump.....FWIW.....
« Last Edit: April 25, 2022, 08:37:10 AM by Cliff Ruggles »

Offline Cliff Ruggles

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Re: Intake manifolds
« Reply #9 on: April 25, 2022, 02:28:08 AM »
https://www.facebook.com/photo/?fbid=10227026615669088&set=a.2010563781498

As for factory intakes and carburetors, check out Anthony Mauro's "hemi-killer" Pontiac Firebird.

Yes, he's using a factory iron intake and one of my Quadrajets.......

https://www.youtube.com/watch?v=_k00pT74-8s
« Last Edit: April 25, 2022, 02:34:47 AM by Cliff Ruggles »

Offline lightning boy

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Re: Intake manifolds
« Reply #10 on: April 25, 2022, 02:02:29 PM »
Hey Old Cars, take a break. although everyone appreciates your extensive "research".
There are some very smart people on this forum who legitimately try to help someone with a problem
There are plenty of other forums where people like to banter back and forth with their expertise, which most often is nothing more than an opinion.
Chill out!

Offline Cliff Ruggles

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Re: Intake manifolds
« Reply #11 on: April 26, 2022, 04:07:00 AM »
I for one like to see DIRECT testing vs googling up your information from Internet sources.

Putting up 2nd or 3rd hand information then referencing someone "famous" like Dave Vizard doesn't cut it.  Just because you are taking warm showers with someone who does some great things doesn't make you a great person.....IMHO.  Nothing wrong with using their input to make your own engines run better and cars quicker, but using that information in discussions to argue the efforts of others DOES NOT CUT it here and will not be tolerated. 

I have been lenient with Old Cars and allowed three personal attacks.  I couldn't imagine putting a comment in public Forum on a persons website that a part he spent many thousands of dollars on to develop to better this industry isn't any better than a part that isn't worth two squirts of duck poop from a parts store.  Who would say something like that right to start with ESPECIALLY if they hadn't tested the part in question......not to mention I do this for a living and sell these parts to pay my bills and keep this website afloat.


Then to tell the same person he doesn't know how to pick camshafts, really?  IF you think that's true take a gander at the attached dyno runs where I was asked to help a speed shop owner/engine builder/dyno operator how to improve power numbers and get his fresh 455 from pinging on hard pulls.

IF I believed everything I read or heard from others about what works and doesn't work with these things I'd never have made it this far in the hobby or as a business.

Just watching Anthony Mauro's "hemi killer" in the link above clearly shows us how good factory parts can be.  Who would have ever thought back in the late 60's and early 70's that Pontiac build using a factory intake/Quadrjajet (almost everyone at that time called them "Quadra-junk") could even run close to Chryslers 426 Hemi with it's two four barrel intake topped with AFB carburetors?

The 426 hemi has every advantage, hemispherical combustion chambers, better intake port layout with HUGE runners, stronger block, crank, rods, over-square design, etc.  Yet a Pontiac engine with a single cast iron 4bbl intake outruns it!

Before someone cries "foul" because of FAST Class rules keep in mind that Rick Mahoney's 400 powered 1968 Ram Air II Firebird runs at the top of the pile in Pure Stock as well.  I also do the carburetors for Rick as he has several Pontiac cars that race in FAST and PURE stock and has been a customer for close to 20 years now.........Cliff
« Last Edit: April 27, 2022, 03:00:17 AM by Cliff Ruggles »

Offline qjetsrule

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Re: Intake manifolds
« Reply #12 on: April 29, 2022, 05:17:10 PM »
Not to mention the Firebird is giving up almost 30 cubes to the hemi. Mr. Mauro must be an incredible tuner/driver. Those Ram Air Firebirds are lethal.

Offline Mudsport96

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Re: Intake manifolds
« Reply #13 on: April 30, 2022, 02:43:48 AM »
From my own personal experience with my 350, i went from a stock iron intake to a Performer. Then to a Torker 2 then a STREET dominator and now i have the first iron intake back on the engine. Albeit i ported it fairly heavily and opened the plenum up like a aftermarket style. It idles and drives so much better than the others. I dont have a big cam and it is done at 5000 so that is a consideration, but it seems to pull better everywhere vs the others.
Would like to try a factory gm 80s aluminum intake as well.

Offline Cliff Ruggles

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Re: Intake manifolds
« Reply #14 on: April 30, 2022, 04:54:30 AM »
The SBC intakes, iron and aluminum are based on the same basic design, even the EGR versions. 

I ran a stock one decades ago to his 11's sitting on a high winding 283 based engine (3" stroke) powering my 1965 Nova SS. 

I tried several other intakes on that combo and found that the only intake that ran faster was a single plane Street Domintor with a 1" spacer on it.  It didn't go any quicker in ET giving up quite a bit of 60' and short times but it did pull like gangbusters in the upper mid-range and top end.  I shifted that engine at 7200-7500rpm's and went thru end of the 1/4 miles in that range as well.  My converter only flashed to about 3800rpms  which is a little low for that sort of engine/drivetrain combo so it didn't whack the tires really hard and left nice making it an excellent bracket car.

I'm probably the only one you will ever hear from that has actually back to back tested half a dozen intake on the same outing at the track.  Have done back to back dyno testing as well.  It's pretty easy on a Pontiac engine as I remove the water crossover and put some car past wax on the gaskets to the intake lifts right off.  I can swap one out in less than 10 minutes.

Even on my the current 455 engine making over 550hp and the old 455 making around 1hp/CID I see gains in 60' and thru the 1/8th mile with the factory cast iron, 455 HO and RPM intakes compared to the single plane Street Dominator, Torker 1, Torker II and Tomahawk single plane intakes.  The engine dyno verifies the power losses below 4500rpm's and stronger top end charge up near the shift point with the single plane intakes, except for the Torker 1.  It's a complete TURD on everything we've tested it on. 

Ran the Torker 1 once on the dyno back to back against my iron intake on a 455 build we did here and it was down 59 HP!  Yes, not a typo, without a spacer we saw a 59hp drop swapping it out on the dyno.

The track testing verified those numbers on Ray's Firebird going from 12.20'a at 109-110mph to 11.70-11.80's at 112-114mph.  Never did figure that one out but I'm thinking the big "shelf" under the primaries to impede "fuel impingement creates turbulence without at least a 1" spacer in place. 

No one reading this would know about all that because they don't back to back test these things, just assume the aftermarket intakes are an improvement because the manufacturers tell us they are.......FWIW.......
« Last Edit: May 01, 2022, 06:22:42 AM by Cliff Ruggles »