Another one. Exhausted

[revster]

For some reason this thread reminded me of this movie.

 

[426Cuda]

For some reason this thread reminded me of this movie.

Ahh Marissa Tomei. You can advance my timing anytime you like!

 

[blackve76]

i just noticed the REX headers I bought are equal length, lots are not equal length(called tuned length)

Does this make any difference? I've googled and looked at you tube and really not got an answer.

Equal length to me means all equal pressure in all pipes which should be good, but some have a bigger bend than others so maybe a little more restricted but the pistion is forcing exhaust out so all this make little to no difference, genuine confused now

 

[Not_An_Abba_Fan]

Are they 4-1 or 4-2-1?

 

[lmoengnr]

Rex headers are 4-1.

 

[blackve76]

What he said 4>1, heres a pic

sorry cuda not try to move in on your thread.

 

[monstar]

i just noticed the REX headers I bought are equal length, lots are not equal length(called tuned length)
Does this make any difference? I've googled and looked at you tube and really not got an answer.
Equal length to me means all equal pressure in all pipes which should be good, but some have a bigger bend than others so maybe a little more restricted but the pistion is forcing exhaust out so all this make little to no difference, genuine confused now

In this design if anything it would spread the peakiness of the torque dome more evenly. It's a good thing. I'd seriously consider putting on a tuned collector and moving the cats back, otherwise leaving a lot of power on the table.

 

[Not_An_Abba_Fan]

Absolutely it makes a difference. Especially on 4-1's. As each pulse reaches the collector it creates a low pressure point in the collector and this scavenges the exhaust gas from the next pipe. However the effect is lost on that design as there is no effective collector. The outlet of the merge is a certain diameter, looks like it could be 3". The "collector" is the length of pipe after the merge before it changes diameter, they look like they have the cat bolted directly to the merge, the cat body is larger than the outlet of the merge so the collector is virtually non existent. The extractors will still work to a degree, but not as well as they would if they had some length after the merge.

FYI, long primary 4-1s that are all the same length are great for bottom end.

 

[426Cuda]

What he said 4>1, heres a pic
All good mate. It's all relevant.
View attachment 196068

sorry cuda not try to move in on your thread.

 

[dimetime]

What he said 4>1, heres a pic

View attachment 196068

sorry cuda not try to move in on your thread.

be wary of these headers as my mechanic has tried fitting these on a few cars and they dont line up very well and he had to go through a few sets from gmm to get a set that lined up, could have been a fluke but still be wary