Down pipe question

[js_customs]

I thought I'd read this info on here before, but I can't seem to find it now. I'm looking to get a new downpipe made for the jeep and I'm not sure what size to go with. For performance crap I have a bored out throttle body, CAI with Amsoil filter, and a flowmaster delta 40 with 2.5" from the cat back. I have the clifford header with the y-pipe so it's going to need to be custom made. Would 2.25" be a good choice?


It's for an 88 4.0L

 

[maybe2fast]

I would try to keep the pipe all 2.5, But the exhaust shop might not like bending the 2.5 the shape of the downpipe. Match it to the size of the collector of the header

 

[Johnnie Walker]

Make sure you go to a place that has a mandrel bender so the pipe DIA stays the same throughout. Definitely go for 2.5" all the way back.

 

[jamiemac]

Make sure you go to a place that has a mandrel bender so the pipe DIA stays the same throughout. Definitely go for 2.5" all the way back.

Not many shops have a mandrel bender. The cost about 5 times what a standard Ben Pearson or Huth brand bender costs, and those benders are 3 to 5 grand used.

 

[Johnnie Walker]

A majority of shops I have been to have them, especially any REALLY GOOD ones. This includes CA, WA state, AZ, and NV.

 

[POLAR_JEEP_04]

Kinda hard to find a mandrel bender here too

 

[Dobbs]

my 92 dosent have the dent in it .I got the jeep with 145,000 on it I guess some one replaced it at some time.Its 2 1/4 from the manfold to the flange where the cat bolts on.Looks like it been on a long time because it rusted bad going to replace the cat and put a cat back system on in a fu mo

 

[Crawler]

If you have the "dent", 2.25" will be a noticable improvement and easiest to fabricate.

Then 2.5" back from the cat through a magnaflow works great on the 4.0L...