The real way to determine proper primary and collector size?

MY FYN 79

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The more I read on the internet, the more I get confused.

I currently run a pump gas 11.0 to 1 6300ish RPM hydraulic roller 406. The headers on my car are coated Hooker 2242 Super Comps. They have 1 3/4 primary tubes with 3 inch collectors. I dont like the primary tube that goes around the frame and limits my turning radius.

The ratio of coated VS. uncoated parts of the headers is equalizing over time :x , so it puts me in a position to have these recoated before they get scaly.. or research some new headers.

I see alot of people talk about how fast their SBCs run with 1 5/8 primary headers. I always read those posts and wonder... are you running that fast because of the headers... or in spite of them?

Could my motor handle a 3.5 collector? Would a stepped 1 3/4 into 1 7/8 be overkill? Would my motor choke with a stepped 1 5/8 into 1 3/4 header? So many questions.. any input guys? Header recommendations, formulas, dyno experiences, tried and true theories?

Thanks in advance for any input!
 

Goob

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Jun 6, 2003
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I'll dig around tomorrow, I used to have a link to a calculator for primary tube size and length.......
 
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Anonymous

Guest
Here, this will make everything perfectly clear...

Clear as mud maybe. :lol:

http://www.burnsstainless.com/TechArticles/Theory/theory.html

http://www.headerdesign.com/

http://www.ssheaders.com/header.htm

http://www.pontiacstreetperformance.com/psp/exhaust.html

At least keep you busy for a while.
 

MonteMike79

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Nov 7, 2003
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Check out the Hedman 1 3/4 headers they stay inside the frame with lots of clearance around everything, they are part no. 65218 I bought coated ones and am very pleased with them. I was looking at the Hooker's but their stupid outside the frame design turned me off. Why go outside when you can stay in ? If you saw the Hedman's and how much room they have and how good they fit, you would say to yourself, what was Hooker thinking when they decided to run those tubes outside the frame.
 
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Anonymous

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MonteMike79 said:
Check out the Hedman 1 3/4 headers they stay inside the frame with lots of clearance around everything, they are part no. 65218 I bought coated ones and am very pleased with them. I was looking at the Hooker's but their stupid outside the frame design turned me off. Why go outside when you can stay in ? If you saw the Hedman's and how much room they have and how good they fit, you would say to yourself, what was Hooker thinking when they decided to run those tubes outside the frame.
How is the collector length on those headers? Is it real short or a fairly good length?
 

540Malibu

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May 22, 2003
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as long as the exhaust gets out of the motor as quickly and efficiently as possible the header details dotn matter.....pretty vague, but it depends 100% on your specific combination
 

Barry 85 SS

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I'd like to know about primary diameters too. I'm running a 548 bbc and some people say I absolutely need 2 1/4" are bigger primaries. Others say 2" in plenty big. I have the 2" Hooker,2241's and would like to know if it is worth the extra money to get bigger custom made headers.
 
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Anonymous

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heavy duty said:
Schoenfeld makes headers that go inside the frame.
and they fit nice and cost a lot less...the paint on them is cheap as hell though.

i run the 1 3/4 stepped to 1 7/8 and they fit nice...but I am turning about 8000 with a 383
 
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Anonymous

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Hey FYN 79, Are you more street crusin or tear'n up the track? What do you have for exhaust. Pipe size,muffles,X-pipe,turn downs after the mufflers or over the axles? I was never really happy with the way 5/8" or 3/4" fit my car with the small block. I ran a set of Stahl 1-7/8" and the fit was great and stayed in the frame with plenty of starter room. They made a HUGE differents from 6200 to 7700 on my 383.
 

MY FYN 79

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Big M Motorsport said:
Hey FYN 79, Are you more street crusin or tear'n up the track? What do you have for exhaust. Pipe size,muffles,X-pipe,turn downs after the mufflers or over the axles? I was never really happy with the way 5/8" or 3/4" fit my car with the small block. I ran a set of Stahl 1-7/8" and the fit was great and stayed in the frame with plenty of starter room. They made a HUGE differents from 6200 to 7700 on my 383.
Hey Big M,

My car is mainly a street cruiser. In 2005 I made it to the track once, and 2006 never put the car on the track. Its just that when I go, I like to make respectable numbers. :)

My exhaust is a 3" full mandrel X-pipe system with Dynomax Ultra Flo mufflers and Monte SS style tailpipes out the back.

Lots of choices out there!
 
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Anonymous

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Well.... with what your doing I don't see why you couldn't drop back to 1-5/8". Like I said before, I didn't really like the fit and spark plug clearance with Hookers on my car with the small block. My buddy had the Hedman's that MonteMike79 was talking about and they fit alot better on his 86 Monte. :D
 

MonteMike79

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My Hedman 1 3/4 fit better than the Dynomax 1 5/8 headers that I have. The coated ones I bought cost me a good buck but for the fit and look they were worth it. They don't come with flanges for exhaust either but if you call whoever you're ordering from you can have them weld them on before coating. I have plenty of clearance around everything including the starter. If you want pictures or anything else let me know.
 

MY FYN 79

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If it wouldnt be too much trouble, I would like to see some pictures Mike. Did you have to ding ANYTHING on the headers to properly fit them?

Dynatech also has a set of 1 3/4 x 3 headers for our cars in a circle track application. I know the 1 5/8 Dynatech circle track ones fit, just not sure on the 1 3/4s.

:edit: Another request if possible Mike. To eliminate any doubt about different measurements on primary/collector and over all length, could you measure from the rear of your lower A-arm mount to the end of the header on both sides? I just stuck the tape measure on the bottom of the mount directly below the thru-bolt. As an example, my Hookers were 13.5" on the driver side, and 17.25" on the passenger.

Thanks! :)
MonteMike79 said:
My Hedman 1 3/4 fit better than the Dynomax 1 5/8 headers that I have. The coated ones I bought cost me a good buck but for the fit and look they were worth it. They don't come with flanges for exhaust either but if you call whoever you're ordering from you can have them weld them on before coating. I have plenty of clearance around everything including the starter. If you want pictures or anything else let me know.
 

MonteMike79

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Here's a couple pics I have, I can get closer ones in a few days probably, but the car is at the body shop right now getting a couple little things fixed so it's not here for me to take specific pictures. I didn't have to ding any tubes or anything, although the driver side clamshell mount I had to notch a little bit out of the corner, not too bad but had to do it. I believe with solid mounts the headers would fit with no modifications at all, but I am running poly mounts with the stock clamshells, so I had to make a little notch. I forgot to mention they are equal length tubes and do fit my angle plug heads. Any other questions or anything let me know



 

MY FYN 79

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Thanks for the pictures. I edited my post before I saw yours! :D

The #1 and #2 tubes look better designed than the Dynatechs, much better for plug wire clearance! If you could get those other measurements at your leisure, that would be great too.

Nice looking powerplant BTW, whats it run?
 

MonteMike79

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sure man I'll get them for ya tomorrow, sorry I missed the post the past few days didn't mean to blow ya off. My cousin built a Monte SS and he said he tried every different set of headers out there and the Hedman's fit the best. He didn't like the Hookers with the multi-piece design going outside the frame. These fit like a glove besides notching the clamshell. I'll measure for ya tomorrow and post back. It's a lil 383 and it runs 11.70s-11.80s right now with some more to be had, I just need to get it to the track some more, one that is actually prepped and doesn't spin. I'm done with the local track after the way the owner talked to me the last time I was there. Here's a picture underneath that I had.

 

MonteMike79

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OK I measured both sides for ya from the control arm mount under the bolt to end of header flange. Driver side was about 21" and passenger side was 25" give or take 1 / 16" on either side. They are long tubes come just about to my crossmember.