Are their many people in this forum that run a true single four inch exhaust. I see a lot of you use the hooker long tubes and duals but what is the fastest anyone has gone with a single exhaust? Just wanna know to see how fast I can possible go before changing my exhaust.

 

A single 3" exhaust can get you into the 11's. A 4" is good for single digits. I know many people in the 11's on a single 3".

Tim

 

Any more info on these cars. I hope to run in the mid tens with a new motor. I have shorty headers a custom mandrel 3 inch y pipe into a 4 inch mandrel bent tube over the diff and into a flowmaster 30 series top ten race muffler.

Do these people running single digits use a shorty header?

 

would a single 3 inch exhaust system be good enough for a 388 to run 10's or 11's? or would I be suffocating the engine?

 

There is a difference between being enough and being right. A 3 inch exhaust on a 10 second car won't keep you from running 10's, but a larger diameter size would be better and you will be faster and have more power. I have a 3 inch y pipe with a 3.5 inch single pipe on my LS1 and would running just a single 3 inch pipe keep me from having 400+ hp, no. Would I have have even more hp with the 3.5?, yes. A 3 inch would be enough, but the 3.5 inch would be better. There is a difference people. If you're only running a 12.7 at 105 then I would say the 3 inch is probably best for you though. At the point you are at it is not a restriction.

 

Ya I realize that my exhuast is not to restrictive for my car as it is right now but I have another motor to put in it that has gone 10.09 and runs consistant ten teens. I will be running the same converter, gear ratio and nitrous system as was run on his combination. I was just wondering if there was anyone who has gone tens with a single four inch because I'm wondering if it has been done.

 

yes it has been done.

 

ive posted this before, but it seems most everyone has forgotten it.

suggested pipe sizes for street performance-

"This is information is provided merely as a guideline to Flowmaster muffler inlet size selection for peak performance at full throttle levels. For vehicles that are street driven on a daily basis, consider using the next smaller pipe diameter for best results."

300-350 ci
single 3" or dual 2.25" for 250 hp
single 3" or dual 2.50" for 300 hp

350-450 ci
single 3" or dual 2.50" for 300 hp
single 3.5" or dual 2.5" for 350 hp
single 4" or dual 3" for 400 hp


choosing the right pipe size for racing applications-

"The table below will help you to choose the correct pipe size for your racing exhaust system. Use it as a guideline as special applications may have specific needs.

single 2.50" for 150-200 hp
single 3.00" for 200-275 hp
single 3.50" for 275-350 hp
single 4.00" for 350-425 hp
single 4.50" for 425-525 hp
single 5.00" for 525-650+ hp

dual 2.50" for 250-300 hp
dual 3.00" for 350-450 hp
dual 3.50" for 450-650 hp
dual 4.00" for 650-800 hp
dual 4.50" for 800-950 hp
dual 5.00" for 950-1100+ hp




there are pipe size recommendations for smaller engines too, but i didnt figure too many people needed that info with camaros

 

Jester is running a single 4" on his twin turbo 350.

Like everyone else said, 4" should be good for single digits.

 

a single 4" exhaust system is only ideal for single digits if you think you can run 9.99s and lower with only 400 hp . you better have one light car . of course you can run 10s with a single 4" exhaust system, but im assuming youre wanting to know what would be the ideal pipe sizes you should run, and not what would be possible to run even though its restrictive. to figure out what would be right for your setup, refer to my post above.

 

Where did you come up with that chart? I believe it is flawed. You don't need that big of piping for the hp you mentioned.

 

its from flowmaster, and i found it in a PAW book. someone else posted similar numbers from a different resource a few months back too. the one section is race-only though....its just for pure racecars that are hauled to the track and never driven on the street.

 

That is a good guidline to follow but it is not to say that you can't achieve more hp then the guidline size with the recommended pipe size. A good friend of mine has gone 9.04 at over 150 mph with dual 3.5 inch pipes. I garuantee you that he makes well over 650 horsepower.

 

I also think that your charts are off. It seems to put the pipes a bit on the large side. I would think that you would be loosing scavenging with that large of pipe copared to those numbers.

 

again, you should go by the street performance chart in most cases. it also says to consider going the next size down for a daily driven car. fastta is completely right.