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Re: Looking for header opinions [Re: challenger451ci] #2601320
01/04/19 02:35 AM
01/04/19 02:35 AM
Joined: Sep 2014
Posts: 4,457
Washington
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madscientist Offline
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Joined: Sep 2014
Posts: 4,457
Washington
Originally Posted By challenger451ci
Originally Posted By n20mstr
Originally Posted By challenger451ci
I'm looking for some real world examples on whether my hoagie would pick up with bigger headers. Current combo in a 3500lb E-body...
528ci Low deck, 12:1 on E85, Indy SR heads Max Wedge ported by Modern. 1050 Dominator. The car is setup for a decent amount of spray with a fogger. 3.73 gear, 28" tire, 2.28 first gear 727. Cam specs: .816"/.799", 284/300 @.050, 114LSA. Current headers are 2" primary 3.5" collector Super Comps that were probably bought during the Reagan Administration. I plan to run mufflers.


WOW, gave up all the info here !!

I can tell you from my real world experience. I went from Pro parts 2" to a set I made 2 1/4 with 4" collector. Really didn't pick up.
Now after getting my engine Dyno'd at BES, he says whats holding it back is the LENGTH more than the diam. He told me 25" long primaries. (my current headers have 35 - 40" primaries, but its hard in an A body without going fender exits) And we have pretty similar combinations.
Also I cant believe you have so much starting line ratio...?



Haha! Well, I figured the only way to get good answers was with good info. Besides, the my junk is waaaay to heavy and down a few hundred HP to hang with you guys!
When you're talking collector length, is that the length before a muffler or including a muffler? I'm on the fence for fender exits. Half my buddies are twisting my arm to do it and the other half have threatened to beat my @ss if I cut the car that much. I'm surprised to hear yours didn't gain with bigger primaries. I know you're throwing some spray at it.
I had 4.10 gear with a stock 1st gear. That was plenty of SLR! Not sure if it could pull a Glide at 3500lbs???



I don't like fender well headers. The primary pipes are always way too long. Collector length starts from where the 4 pipes come together (assuming 4-1 headers) and terminates at the point where you have a reducer, or the collector stops. If you have a full exhaust, it's a bit different. If there is pipe right off the collector, I count that as collector IF it's the same diameter as the collector. If it's smaller than I don't count that. If you bolt a muffler right on the end of the collector then it's collector length.

Again, if using mufflers I always go up one size in collector. Fender well headers have at least two faults. Primary tubes that are way too long and a collector that's way too short.


Just because you think it won't make it true. Horsepower is KING. To dispute this is stupid. C. Alston
Re: Looking for header opinions [Re: challenger451ci] #2601379
01/04/19 10:44 AM
01/04/19 10:44 AM
Joined: Aug 2003
Posts: 4,699
On the parachute mount
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n20mstr Offline
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collector length ? well if you plan on running a muffler I guess that would be included in the overall length. I would say go bigger if its longer. Instead of 4" consider 5"

The fender exits...Ughhh I really don't like them, but they are the way to a real short primary tube. Again you probably want 25-30" max. If you going fender exit im assuming you going to use a Burns type real short muffler? If under car then do what I did, Cut a cheap dynomax or similar straight through, I cut 5" off each end and ...there you go instant "shorty" mufflers LOL.

On the SLR, don't be shy. Im leaving in 2nd (1.48) and 4.11 out back.
I hate to say it but the trend right now is 1.40 or less and 4.30 or more. Works well with little SLR and a lot of gear out the back to pull the car through. Those 3.73 gears are lugging the car on top, but I know you got to work with what you got. Less SLR will always help with No Prep and junk tracks. If possible consider going back to the 4.10 or 4.30 and get a valve body that will allow leaving in 2nd. This also may require a stator change in your converter. Yes the powerglide could be a good option for you. It will also dump a bunch of weight over that 727...lots of stuff to think about

Do you have any racepak or data logger ? A sportsman racepak will give you so much real world info and help you see whats going on, it will eventually pay for itself in good decisions rather than useless testing. especially with converter and gearing...

Last edited by n20mstr; 01/04/19 10:46 AM.

....BAD A$$ STREET CAR.....
Re: Looking for header opinions [Re: n20mstr] #2601536
01/04/19 03:58 PM
01/04/19 03:58 PM
Joined: Mar 2008
Posts: 292
NY
challenger451ci Offline OP
enthusiast
challenger451ci  Offline OP
enthusiast

Joined: Mar 2008
Posts: 292
NY
Originally Posted By n20mstr
collector length ? well if you plan on running a muffler I guess that would be included in the overall length. I would say go bigger if its longer. Instead of 4" consider 5"

The fender exits...Ughhh I really don't like them, but they are the way to a real short primary tube. Again you probably want 25-30" max. If you going fender exit im assuming you going to use a Burns type real short muffler? If under car then do what I did, Cut a cheap dynomax or similar straight through, I cut 5" off each end and ...there you go instant "shorty" mufflers LOL.

On the SLR, don't be shy. Im leaving in 2nd (1.48) and 4.11 out back.
I hate to say it but the trend right now is 1.40 or less and 4.30 or more. Works well with little SLR and a lot of gear out the back to pull the car through. Those 3.73 gears are lugging the car on top, but I know you got to work with what you got. Less SLR will always help with No Prep and junk tracks. If possible consider going back to the 4.10 or 4.30 and get a valve body that will allow leaving in 2nd. This also may require a stator change in your converter. Yes the powerglide could be a good option for you. It will also dump a bunch of weight over that 727...lots of stuff to think about

Do you have any racepak or data logger ? A sportsman racepak will give you so much real world info and help you see whats going on, it will eventually pay for itself in good decisions rather than useless testing. especially with converter and gearing...


Thanks for all the input! I value everyone's help.
Fender exits are pretty much not an option at this point. I still like to drive the car occasionally. Loud is one thing...4"-5" open header mufflers out the side is a whole new level of obnoxious. I'm going to see what I can fit up close to the headers and keep everything as short as possible. Right now it's 3.5" all the way back to 2 chamber Flowmasters right in front of the rear. So it's a very loooong and small diameter collector the way it sits. Gotta be killing some power on the big end I would think.
Lenny at Ultimate told me I'm most likely driving thru the converter with 3.73's and a 29" tire and it's about as tight as he can make it. One of the reasons I knocked the tire down to 28", but still not going to make the difference back to a 4.10. Now I'm trying to stick the 28" tire....It's a vicious circle! The 2.28 1st gear did make it possible to get on the ramp a little faster than the stock 1st gear.
I have a 2nd gear leave CRT valve body but can't get a decent high gear shift. RPM drops about 300-400 from 2-3 on the sauce. Put an A&A VB back in and it's back to 700-800rpm on the 2-3. I haven't had the time to dig into that, but wanted to try 2nd gear for sure especially for zero prep stuff.
I use an LM-2 that I've added Pan vac, nitrous pressure and fuel pressure sensors to. It's no Racepak but helps see what's going on.

Re: Looking for header opinions [Re: challenger451ci] #2601671
01/04/19 09:20 PM
01/04/19 09:20 PM
Joined: Aug 2003
Posts: 4,699
On the parachute mount
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n20mstr Offline
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n20mstr  Offline
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Joined: Aug 2003
Posts: 4,699
On the parachute mount
you racing through the mufflers ? If so i would bet its a lot faster open headers ...youll lose a lot of weight, those flowmasters are heavy, and they really dont flow well either lol.

Have you tried tractor fluid in the trans ?

Last edited by n20mstr; 01/04/19 09:22 PM.

....BAD A$$ STREET CAR.....
Re: Looking for header opinions [Re: n20mstr] #2601874
01/05/19 12:42 PM
01/05/19 12:42 PM
Joined: Mar 2008
Posts: 292
NY
challenger451ci Offline OP
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challenger451ci  Offline OP
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Joined: Mar 2008
Posts: 292
NY
Originally Posted By n20mstr
you racing through the mufflers ? If so i would bet its a lot faster open headers ...youll lose a lot of weight, those flowmasters are heavy, and they really dont flow well either lol.

Have you tried tractor fluid in the trans ?


Yep, right through the ancient, heavy Flowmasters! I occasionally still run where open headers might be frowned upon. Would be an easy check to see how much it picks up.
I do have JD low viscosity oil in the trans. I'm going to try the high viscosity. I also think I need to bump the line pressure, but will see with the heavier fluid. Lenny also wants me to make sure I have enough pressure in the cooler lines. Apparently low pressure there can cavitate the converter.

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