Another topic for discussion

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sverbus
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Another topic for discussion

#1 Post by sverbus » Fri Mar 19, 2010 2:21 pm

I don't think I've ever seen this topic on here in the years that I've been trolling this site. But with the rack & pinion that I'm putting on this year, I'm going to finally be able to install my adapter plates to the heads, and bolt on the badass Stahl headers that I bought off of Craig W. at the beginning of last summer.

They are 1 7/8 into a 3.5" collector. And in watching what guys run at the track and even on the street with big stroker SBC's like mine, I see alot of them running big headers like I'm going to, and then they run 3.5" exhaust all the way and through bullet style or 2-chamber mufflers.

I want to get as much flow with the exhaust on as I can, so I'm guessing that after I get this motor running right, it should be able to utilize 3.5" exhaust. Any advice/opinions on that? I currently run a 3" collector with 3" exahust through 2 chamber 40series FlowMasters.

AND....I was trolling the net and came across Dr. Gas's website..where they sell oval exhaust tubing and even have a conversion chart that tells you what size you need in oval, for whatever size you were going to run in round. So, 3.5" exhaust is going to kill alot of ground clearance, but if I run oval exhaust, the oval equal is 2.5" x 4" oval. that gives mea solid 1" of ground clearance extra.

So I'd adapt my collectors to go from round to oval (dr. gas makes these) and from oval to round for my bullet mufflers that I have, and then dump out by the rear-end again with simple dumps.

Any of you wild guys have some info on this? How does it sound and if you think it's worth it to run that large of a exhaust pipe. :) :bling:
'70 Nova
434 small block
Best so far of 10.51 @ 131mph with a best so far 60' /1.46

waterdog
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Re: Another topic for discussion

#2 Post by waterdog » Fri Mar 19, 2010 8:17 pm

sverbus, I've got 1 7/8" hedman race headers with 3 1/2" pipe to flowmaster race mufflers. The mufflers sit under the front seats with turndowns angled inward, it is loud but not punishing and sounds badass. I just got a some spintechs with oval pipe that's gonna give me alittle more ground clearance. Walt
1970 Nova SS 3580lb, Shafiroff 434 na, 9.94@135.8

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sverbus
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Re: Another topic for discussion

#3 Post by sverbus » Wed Mar 24, 2010 11:13 pm

Wow...no other responses/opinions/advice on this subject? Interesting...
'70 Nova
434 small block
Best so far of 10.51 @ 131mph with a best so far 60' /1.46

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John_Heard
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Re: Another topic for discussion

#4 Post by John_Heard » Thu Mar 25, 2010 6:06 am

Never tried to run that big of exhaust that far back. I think the biggest I ever ran on mine to the back axle was 3" with an X pipe, that was on the old small block and that worked out fine. Didn't have trouble with clearance.

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supernova
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Re: Another topic for discussion

#5 Post by supernova » Thu Mar 25, 2010 6:35 am

I have 4" under my car with 5" Dynamax bullets. The mufflers are at the rear floor pans with turn downs under the rear set. The rear floor pans drop down lower than any other part of the floor so I cut out and tunneled the rear floor to gain more clearance for the mufflers. I also tucked the rest of the exhaust as tigh as I could under the car. I have pics and will load them later today.
Last edited by supernova on Thu Mar 25, 2010 8:20 am, edited 1 time in total.
Blackhoodmafia!!!! :mrgreen: :mrgreen:

1972 Nova SS
572 C.I. BBC

Best to date: 1/8
et: 5.28
mph: 134
new wt. 3340 lbs

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ytnova
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Re: Another topic for discussion

#6 Post by ytnova » Thu Mar 25, 2010 7:00 am

I have a full 4" exhaust under my car with a x-pipe as well. I have never had any clearance issues and my car sits pretty low. I have some old picks with the racer bullets, but none with the new vibrant mufflers.
I am not really sure what the question is, but I am pretty sure the answer is Big Block.

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John_Heard
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Re: Another topic for discussion

#7 Post by John_Heard » Thu Mar 25, 2010 7:03 am

ytnova wrote:I have a full 4" exhaust under my car with a x-pipe as well. I have never had any clearance issues and my car sits pretty low. I have some old picks with the racer bullets, but none with the new vibrant mufflers.
You got any bye run video of the car with that setup on it? I'm curious what it sounds like...

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sverbus
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Re: Another topic for discussion

#8 Post by sverbus » Thu Mar 25, 2010 2:29 pm

well than maybe the 3.5" won't be to bad to tuck up under there...have to play with it!
'70 Nova
434 small block
Best so far of 10.51 @ 131mph with a best so far 60' /1.46

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ytnova
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Re: Another topic for discussion

#9 Post by ytnova » Fri Mar 26, 2010 9:05 am

I can't play any video's here at work, but here is a link to saturdays qualifing, about half way down on the page in the heavy street class. I should be making a pass with a g-body in the other lane, but he spun so you should be able to hear just my car on the top end, I think it was a 9.xx something pass, but it gives you and idea.

http://www.streetlegaltv.com/forum/orla ... l#post7642
I am not really sure what the question is, but I am pretty sure the answer is Big Block.

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Re: Another topic for discussion

#10 Post by John_Heard » Fri Mar 26, 2010 10:09 am

That's about what I thought it would sound like. Sounds good, I like the sound of an X pipe.

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