4 inch exhaust

[sparks57]

I don't remember off the top of my head... I knew a month ago...



PM Nascar Mark or Pastor Bob, they can tell you. Mark makes them as far as I know.

 

[Greenleaf]

quikshft...........

... ... ... you have mail



Greenleaf

 

[RGT]

I like the 2 piece 4" pipe that goes past the transfer case I got from Stan's, I am pretty sure they would sell just that pipe, without the whole system, ... .

 

[JLEONARD]

I said the same thing he did, no power to be gained

Well, I had a decent power increase by going from the stock 3 inch to a 4 inch system.

No dyno numbers, but I'll describe it and you guys can judge for yourselves.

I recently installed a sytem from Janetty... . 3 inch downpipe, then 4 inch the rest of the way... also put in the muffler.

I saw a 2 to 3 psi increase in max boost.

I saw a very noticeable increase in spool up... the needle literally jumps now when I nail the go pedal.

Low end turbo lag is reduced by a noticeable amount.

Cooldown time is greatly reduced... I used to have to wait about 15 seconds after I backed into my parking spot at work before the pyro get to 300 deg... . now I'm at 300 by the time I'm backed in.

I did not notice any decrease in EGT.

I would say my results show that a marked performance improvement can be had by switching to a 4 inch exhaust with a low HP engine.







Jay

 

[glhs]

I too am looking to buy a complete 4'' system. I contacted Rip Rook a couple weeks ago and he said he was still waiting to get a 4" downpipe to complete the system. For now it is a 3" downpipe. Does anyone know if the PDR 4" downpipe is long enough to connect into the Rip Rook system? When I get it I will be selling my complete Banks exhaust system.

Kurt

 

[dpuckett]

glhs,

is the Banks downpipe 3. 5"? If so, I may be interested in just it. If not, I'll have to do some thinking, (oh boy ) and make my own 4" DP. I plan to start at the tailpipe and work my way forward. straight 4" pipe is like $3. 50 a running foot, and $50 for the 2-45s and a 90.



ANyone know where I can get a 3-4 adaptor? Muffler shops here only have 3-3. 5, then a 3. 5-4; @$25-30 apiece!! That's more than I plan to spend on the rest of it.



Daniel

 

[Forrest Nearing]

I've got a 3-4" adapter I'll give ya. email me at:



-- email address removed --



Forrest

 

[Wayno]

If I remember right the Banks down pipe is 3 , but its been awhile since I have been under my truck . I took the Banks muffler off my truck and put a straight pipe on it (some time back) and got the turbo lag back so the big amazon Banks muffler went back on . It looks to me the turbo outlet is just so big ( what like 3 in. ) so only so much exhaust is going to come out even if you put a 8 in. exhaust on it . Now a little port and polishing and a different turbo and exhaust manifold might change that . What ya think Joe D.

 

[sparks57]

Rip rook is going to make me a full 4", downpipe and all (and 5" tips). I'm just going to duplicate the dual system I have now.

 

[JLEONARD]

It looks to me the turbo outlet is just so big ( what like 3 in. ) so only so much exhaust is going to come out even if you put a 8 in. exhaust on it

I agree... . but there are some 90 bends, so a 4 inch would relieve some of this pressure reduction I suppose... at least in theory.

Personally I didn't think it would make that much difference in my set-up... . but it would be interesting to actually try one to compare.

Jay

 

[dpuckett]

Depending on how tight the turn is in the 90s I get, I may make it a full 4" from turbo back, or right behind the turbo; otherwise, I'll put the first not so tight 90 the bottom half of the downpipe.



Forrest, you'll have mail in a minute or two.



Daniel

 

[HonkinDiesel]

Having gone through this situation last year, unless you can find someone to do the 4" custom work (which I found mostly impossible around this town) or you are equipped to do the mandrel bending and welding yourself... . Good luck!



Almost all off the shelf kits have 3" downpipe and convert right after to 4". I think the key is to have good smooth flow without sharp bends and kinks (unlike the stock system does).



On the old stock system, my tail pipe was crushed just between the rear axle and the frame. What a stupid place to put the tail pipe!



To make a long story short. . Shopping around I eventually went with the Bullydog 4" Exhaust kit. Not a bad price at $500 and fairly easy to install (about 3 hours for backyard mechanic with few tools required). I had to make my own hangers.



With the Bullydog exhaust it was easy to route the tailpipe beside the frame. So now I don't use my tail pipe in an axle frame sandwhich, when I go onto those rough trails.



Once installed, I love the nice rumble sound, noticed a bit of mileage improvement (I'm getting about additional 50 km or 31 miles/tank on a combined city and highway commute), and acceleration is noticably faster too.

Soooo take or leave it, I'm convinced this was a worthwhile upgrade.



You hear it time and time again... if want more power, you need to increase the airflow to the intake as well as flow through the exhaust. (Refer to Banks, Bully Dog, or anyone else that knows about getting more power out an engine).



Kind Regards to those who contributed to this thread and hope I did'nt step anyone toes with my comments. Just my honest opinions and observations.

 

[quikshft]

Hmmm, sounds like there could be a market for some nicely constructed 4 inch down pipes... Too bad I couldn't make a living building those, I'm tired of working for one.

 

[sparks57]

You're a little late... Rip Rook and Mark Wilson make them already.

 

[JFitzgerald]

Originally posted by dpuckett

glhs,

ANyone know where I can get a 3-4 adaptor? Muffler shops here only have 3-3. 5, then a 3. 5-4; @$25-30 apiece!! That's more than I plan to spend on the rest of it.



Daniel

You probably have one by now, but in case it helps someone, I bought a 3-4" adapter at NAPA when I put a 4" tailpipe on the '93 a couple years ago. It's probably a Walker item.