does anyone know if there is a benifit of running a merge collector on a F/I motor?

i know they help the scavanging of the combustion gases , but with boost the gases are forced out anyway.

what do you think?

 

That's a good question..I have FLP's and i would like to open up the merge section alittle. I'm installing a 8# ATI with heads/cam soon so i would think opening up the merge collector on the FLP's would help. I'll just get a 3 inch piece of t-304 pipe and have a muffler shop cut the squashed section and weld in the new piece of pipe. Just a thought.

 

From what i have heard, merge collectors aren't worth the money on s/c cars, they are meant to scavenge exhaust gasses, and spped the flow more, but on s/c, you are already pushing the air in and out of a motor anyways, so it's not as much of a concern, if anything, i would think that the taper on a merge collector would hurt in a s/c application.

<small>[ March 15, 2003, 06:28 AM: Message edited by: ZYA_LTR ]</small>

 

Yes, you want to use a merge collector. Burn's Stainless and Specialty Products Design offer pre-made, double slip, turbo merge collectors featuring an internal diffuser cone. A 15* taper is typically ideal for most applications.

On street turbo applications, backpressure between the turbine and exhaust valves are typically 2x greater than manifold pressure (boost) so anything you can do to lower backpressure and increase efficiency and scavenging is beneficial. Of course there are plenty of non-optimized header/exhaust manifolds out there that work very well, but if you want to do it right, equal-length, tuned headers are still the way to go with turbos.

 

but that's on a turbo motor, how about a supercharger motor?? does this still hold true?

 

Of course, you still want to aid in scavenging the exhaust as much as possible. The exhaust side of an S/C motor is the same as a N/A motor, except it needs more help evacuating the exhaust since you are forcing more into the intake under boost. Look at any professional/race S/C or turbo car...

 

Supercharged applications like big pipes, but exhaust scavenging does little for Supercharged motors. If you have the money to burn, go ahead. But, it could best be used for something else that will make a real difference.