Thread: 4-1 Headers talk!!

I am curious to see the truth about 4-1 headers being better than the headers we have been using at the time that are basically the pipes and the merge collectors of a Honda tri -y headers
I was thinking of building a 4-1 header using 1.75in stepped to 1.88in maybe from 21-23in long primaries into a nice 4-1 merge collector with a magaphone a reverse cone!!! Any input from the guys using 4-1 headers with good results will be welcome!!

Subscribe very interested in this thread due to 4-2-1 headers holding me back

JMR header all the way if you can find it

Burns Stainless LLC - Technical Articles

Have fun!

That spec looks similar to a mike k. Spec, ive tried a megaphone and a reverse cone on a tri y.
jmr spec looks promising.
Interestd in a spec that wud outperform the tri y

Payu: 21in sounds very short to me... id stick to 23-25in at least. I will be trying probably 1.75in primaries, 2.1in choke to a 3in transition. I have this merge collector, very nicely built for good price.

Please remember to do some before and after dyno charts if you can. This could be interesting.

i am using a custom 4-1 [designed by Blo0d]

23" x 1.75 runners and formed collector

it was used to do the fastest stock 20ve time in Ja so far - 13.1 second in n14 chassis

on my stock motor [n1 cams] i have used it to dyno 195whp and 213 on a high cr build with n1 cams



my plans were either:

1. tri y

2. step it halfway the runner to 1.875" and change to a merge collector

@ Payu, it would be good to do a 4-1 as you have spec'd and compare to your guys tri y results

peace

here is one i have made, yet to be tested, 1.75 primary into about 24" primary each runner is equal length, not sure if they suppose to be with in about 1" then merge into a 3" collect then drops down to 2.5" and then about 12" of pipe before the 2.5" muffler