you did not gain that much just from a merge. Not possible. Unless you dynoes your car b4 and after.
Sorry bud, your strectching it a little to far
He didn't gain that just from a merge, he gained that from the merge, and I-pipe together. Having a 4" I-pipe greatly increases exhaust flow, and will allow maximum power for a Y-pipe. Someone posted the correct math before, but I will explain it a little more.
You have to think about two 3" pipes merging into each other. The combined area of two 3" pipes from your Y-pipe would be 14.13 square inches. If you have a 3" I-pipe, you have an area of 7.065 square inches. Which now means you are dumping a combined 3" Y-pipe into 7 square inches, or basically halving the output. If you were to merge into a 4" I-pipe, the 4" I-pipe has a area of 12.56 square inches. The 4" pipe has 43% more area than the 3" pipe. It also almost matches the output of two 3" pipes, which will greatly increase exhaust flow. Also just for reference, a 3.5" I-pipe would only have an area of 9.6163 square inches. The 4" pipe still has 23% more area.
If you want to check the math, Area of a Circle, A = Pi * r * r. In this case, we are dealing with diameter, so you would first convert diameter to radius ... d / 2 = r.
He didn't gain that just from a merge, he gained that from the merge, and I-pipe together. Having a 4" I-pipe greatly increases exhaust flow, and will allow maximum power for a Y-pipe. Someone posted the correct math before, but I will explain it a little more.
You have to think about two 3" pipes merging into each other. The combined area of two 3" pipes from your Y-pipe would be 14.13 square inches. If you have a 3" I-pipe, you have an area of 7.065 square inches. Which now means you are dumping a combined 3" Y-pipe into 7 square inches, or basically halving the output. If you were to merge into a 4" I-pipe, the 4" I-pipe has a area of 12.56 square inches. The 4" pipe has 43% more area than the 3" pipe. It also almost matches the output of two 3" pipes, which will greatly increase exhaust flow. Also just for reference, a 3.5" I-pipe would only have an area of 9.6163 square inches. The 4" pipe still has 23% more area.
If you want to check the math, Area of a Circle, A = Pi * r * r. In this case, we are dealing with diameter, so you would first convert diameter to radius ... d / 2 = r.
where can you get a 4" I pipe from?
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I have the same Spohn TQ. It will fit in there, I have the 3 in 4 out setup, and it fit, barely. You have to put the merge in there, and then cut accordingly. I'm not sure how far your Y goes back into the loop.
I had a custom piece done, that looks like shit, so I'm about to do it with the Eldebrock Y. Plan is to cut that Y right where it merges, place the Flowmaster Y where it fits best, and then cut pieces to bridge the gap. I'll post up pics when I'm done.
Yeah some pics would be great. Thanks for the info...
He didn't gain that just from a merge, he gained that from the merge, and I-pipe together. Having a 4" I-pipe greatly increases exhaust flow, and will allow maximum power for a Y-pipe.
Everything you say is true, but you also need to take into account the output of the motor to determine the most effective pipe size. Piping that is too big will cause loss of exhaust heat and velocity. Too much pipe for too little motor doesn't gain anything.
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Everything you say is true, but you also need to take into account the output of the motor to determine the most effective pipe size. Piping that is too big will cause loss of exhaust heat and velocity. Too much pipe for too little motor doesn't gain anything.
Oh I agree. It just seems this setup works well for mild to highly modded LS1's. Let me rephrase, it is the best y-pipe setup I have seen on any modded LS1's to date.
It is nothing more than a pipe that goes from the collector to the catback. The correct term is intermediate pipe, but I just say I-pipe for short. If you have the proper merge collector, it would be an easy swap, then just reduce it back down to 3" or whatever your catback size is.
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