Inliners International
Posted By: chevy 250-6 pipe size for 250ci - 02/14/07 12:47 AM
i was just wondering what size pipe people have used on true dual exauhst. i plan on using 1.5" straight pipes with langdons headers. will this give me the loud pop and crack when i rev it and the rapping when it is under load.

also if people could post any pictures of how they ran their dual pipes
Posted By: tlowe #1716 Re: pipe size for 250ci - 02/14/07 12:53 AM
when i ran duals on my elco, i used 2 1/4 pipe and ran them next to each other all the way. it has a better sound if both pipes come out at the same spot. sounds worse if pipes are on opposite sides of car. i also used glass packs. tom
Posted By: chevy 250-6 Re: pipe size for 250ci - 02/14/07 01:03 AM
for the "split six" sound should the pipes be on the same side or opposite sides of my truck
Posted By: tlowe #1716 Re: pipe size for 250ci - 02/14/07 01:12 AM
i vote for same side. opposite sides sound ''dorky''. tom
Posted By: John H. Meredith Re: pipe size for 250ci - 02/14/07 06:08 AM
The sound is determine by the type of mufflers used and there are many to choose from. Most use 2" pipes to the mufflers (in) and 1.5" (out).

It's important that the pipes remain separate for many reasons and running them on the same side, works best for trucks.

If you check the past posts you'll find several pages on this debate.

Good luck. \:\)
Posted By: inline300 Re: pipe size for 250ci - 02/14/07 11:46 AM
Any chance you can meet up with some inliners, with different exhaust systems, that would be ideal?

Good luck!!
Posted By: Road Runner Re: pipe size for 250ci - 02/14/07 12:26 PM
The smaller diameter and longer, straight pipes, the more they rap and the higher the pitch of the exhaust tone.

1-1/2" pipes on a 250 should rap plenty and also help with low end torque.

On my 235 I wouldn't go lower than 1-3/4" pipes, as it would feel choked at higher rpm and freeway driving.
For city only and midrange rpm - perfect.
I have 2" pipes on mine and that feels still choked on the freeway above 2500 rpm.

For the 250 the numbers are probably about the same, I would think.
Posted By: strummin67 I.I. Re: pipe size for 250ci - 02/14/07 12:39 PM
Make sure the louvers face the direction of the exhaust flow. I have a 2" system.
Posted By: John H. Meredith Re: pipe size for 250ci - 02/14/07 02:11 PM
It's all in the mufflers.

See what's in the salvage yard. If you calmp them on, there easy to 'change out' later, or you could start with 30" glasspacks (new).

Listening to others is helpfull too.

Happy trails. \:\)
Posted By: Randy S. Hager Re: pipe size for 250ci - 02/14/07 07:37 PM
What would work for best torque. I don't care if it even makes a sound, I just want the most torque I can get out of a Chevy 250 and a 2bbl TBI on an OFFY 4bbl intake (on outside holes) with full lenght headers. Just plain and simple!

Randy S. Hager
Venus, TX
Posted By: inline300 Re: pipe size for 250ci - 02/15/07 11:29 AM
 Quote:
Originally posted by Randy S. Hager:
What would work for best torque. I don't care if it even makes a sound, I just want the most torque I can get out of a Chevy 250 and a 2bbl TBI on an OFFY 4bbl intake (on outside holes) with full lenght headers. Just plain and simple!

Randy S. Hager
Venus, TX
Single outlet header, Id say a single 2.25" pipe, would work fine.

For dual outlet header, add a Y pipe and run a single pipe.
Posted By: border_line Re: pipe size for 250ci - 02/18/07 02:51 AM
I ran 2 1/2" pipes, side by side on my truck,flowing thru Summit welded mufflers (part# SUM-633222) which turn out just before the rear tire. I don't get much cracklin'-n-poppin', but then, I wasn't goin' for that sound..... Wanted a nice low rumble. Also, I've got a 292, don't know how different 2 1/2s would sound on a 250.I would post pics if I had the technological know-how but lacking in that dept.(sorry)
Posted By: John H. Meredith Re: pipe size for 250ci - 02/18/07 09:28 AM
Dear Randy;

For the best torque leave it (the exhaust) stock, or use the 292 CID (3 bolt) manifold.

Headers/dual exhaust add to the "top end" and remove extra heat from the engine.

Running headers/duals into a single pipe is a waste of time & money and defeats their purpose.

Checking past posts on this may help you understand.

Good luck. \:\)
Posted By: inline300 Re: pipe size for 250ci - 02/18/07 10:57 AM
Randy S. Hager

Definitely search for information, as there are theories/fact that long tube headers actually increase torque. You be the judge.

I was under the impression you had the dual headers already, if not, it would be easier just to go with a six into one header or just keep the exh manifold.


border_line

If interested, PM me and maybe I can help you figure out how to get pictures into your posts, Im no expert but Ive had success in the past.

Or if you have the pictures on your computer, email them to me, and I will post/host them for you.

Have a good one
Posted By: TP from Central PA Re: pipe size for 250ci - 02/19/07 03:52 PM
I ran 2.5" off the headers on my 250.....Due to cross members on the 4x4, I had to y them together into one and dump it out in front of the rear wheel on the drivers side........Works ok. I am running a glass pak.

We had a '69 C-10 that we ran 2.250 from the stock exhaust manifold to right behind the cab, did a 45 degree turn and then a 90 in front of the step box fender to a stack.........It was the most awesomest sound out of a gas engine that I ever heard!
© Inliners International Bulletin Board