truck4canuk
Active Member
i have an offy dual 4 intake #5492. i cannot find any documentation on what sort of flow it likes best... anyone able to help?
offenhauser 2x4 intake and flow rates
- Thread starter truck4canuk
- Start date
You probably won't find any flow numbers, but we have used one in the past and they are terrible. Look cool though !!!
Dave
Dave
truck4canuk
Active Member
That seems to be my luck! I guess I should talk to you all before I get caught up in the 'shiny / nifty' stuff!!!
truck4canuk
Active Member
i knocked out the pistons... it turns over easier, but i don't have any better news!
took some pics, but there still too big... i will work on reducing them to post!
took some pics, but there still too big... i will work on reducing them to post!
truck4canuk
Active Member
I have the "tall" version of that intake on one of my W engines, only because I built it before the Eddie was released. I spent WAY too much time inside that thing trying to help it out...it looks kinda neat but it's not too well designed by todays standards. It just had a lot of sharp edges and corners, as I remember.
truck4canuk
Active Member
I think the dual 4 - well, .... it's sexy! 
I can limit the secondaires on the carters if I have too much flow...
I can limit the secondaires on the carters if I have too much flow...
They do have terrible 90 degree bends but you can still make good power with the single quad manifold. One of our members (Travis Horton) had a single quad 409 that ran really well. I think he ran high tens in the quarter mile so he must have been making well over 500 hp.
Edelbrock also makes a single quad 409 manifold. I'm sure it would make even more power.
Didn't he mention that at the 04 convention is KC?
Skip FIx
Well Known Member
Maybe using a single 4 on HIS intake, not a factory single 4. Iflowed one on my ported E heads and it killed the flow way more than the factory dual quad, which was worse than the Eddy dual quad. Now an Eddy single might not be too bad. Lot's of guys do go faster with a single 4 than 2 4s if they have a decent intake.
Back in '65 on the advice of a fellow racer I went from tri-power to single four on my '60. The advantage was to drop from C stock to D stock, plus he said the car would be quicker (which I doubted). Well, I was wrong. Went from 14 teens and low 20's to 14 0's and high 13's. But, I have to admit that intake was a little slick in the runners. 
Lonnie
Lonnie
truck4canuk
Active Member
Well - here's what I have decided...
There are few who think this is either pure art or pure science....
Personally; I think it is a combination of both.
When anyone makes a choice to use "old technology" they are proving that statement true.
So, as long as I am using small port heads, I will use the dual 4 offy...
Reason #1 It WILL work (well enough to keep a smile on my face)
and
Reason #2 They look so friggin' cool!
There are few who think this is either pure art or pure science....
Personally; I think it is a combination of both.
When anyone makes a choice to use "old technology" they are proving that statement true.
So, as long as I am using small port heads, I will use the dual 4 offy...
Reason #1 It WILL work (well enough to keep a smile on my face)
and
Reason #2 They look so friggin' cool!
Yes, I think they look great too. They aren't terrible but I'm sure the new Edelbrock would be better.
I think the problem with the Offy style intakes is the short runners. They never make great power in any of the tests I've seen.
Here's a big intake manifold test on a 383 Mopar.
http://www.hotrod.com/techarticles/hrdp_0712_mopar_intake_manifold_comparo/viewall.html
The Offy dual quad made.......................................... 425 hp and 431 ft lbs of torque.
A single quad Edelbrock Performer RPM made....... 451 hp and 457 ft lbs.
In part two of the test they bumped up the horsepower.
http://www.hotrod.com/techarticles/hrdp_0801_mopar_intake_manifolds/
The Offy made............................................................... 475 hp and 437 ft lbs on that engine.
The Edelbrock RPM made............................................. 505 hp and 470 ft lbs.
A Weiand tunnel ram made the most power with....... 540 hp and 494 ft lbs.
I'd love to see someone compare a single quad Edelbrock to a dual quad on a 409. I think the single quad might make more average power on engines with less than 450hp but the twin carbs might start to pull away on the more powerful engines.
The single quad has the advantage of longer runners but at some horsepower level it might be more important to have the extra carb.
I remember reading the specs on a couple of Edelbrock crate engines. The only difference was the carbs and manifolds. The dual quad engine made 10 hp LESS than the single quad engine. The engines were fairly mild 350's with about 320 hp if I remember right.
I think the problem with the Offy style intakes is the short runners. They never make great power in any of the tests I've seen.
Here's a big intake manifold test on a 383 Mopar.
http://www.hotrod.com/techarticles/hrdp_0712_mopar_intake_manifold_comparo/viewall.html
The Offy dual quad made.......................................... 425 hp and 431 ft lbs of torque.
A single quad Edelbrock Performer RPM made....... 451 hp and 457 ft lbs.
In part two of the test they bumped up the horsepower.
http://www.hotrod.com/techarticles/hrdp_0801_mopar_intake_manifolds/
The Offy made............................................................... 475 hp and 437 ft lbs on that engine.
The Edelbrock RPM made............................................. 505 hp and 470 ft lbs.
A Weiand tunnel ram made the most power with....... 540 hp and 494 ft lbs.
I'd love to see someone compare a single quad Edelbrock to a dual quad on a 409. I think the single quad might make more average power on engines with less than 450hp but the twin carbs might start to pull away on the more powerful engines.
The single quad has the advantage of longer runners but at some horsepower level it might be more important to have the extra carb.
I remember reading the specs on a couple of Edelbrock crate engines. The only difference was the carbs and manifolds. The dual quad engine made 10 hp LESS than the single quad engine. The engines were fairly mild 350's with about 320 hp if I remember right.