turbos
Hotshot
Joined: Jul 2008
Posts: 11,231
Likes: 130
From: Thomasville, GA
If you don't already have a aftermarket downpipe, then putting in a 3" isn't very hard. You definately don't have to pull the engine, and if you want it to mate up to the 4" exhaust get a downpipe from Tymar that is 3" at the top and then expands to 4" at the bottom.
New User
Joined: Dec 2005
Posts: 5
Likes: 0
From: Americus
Is a backpressure can neccessary with bigger exhaust?
Hotshot
Joined: Jul 2008
Posts: 11,231
Likes: 130
From: Thomasville, GA
It's not neccessary...
With 4" exhaust you are perfectly fine and it'll be capable of 500+ horsepower.
5" will slow down the exhaust gasses and have less back pressure so it won't perform as well on a lower hp truck, but not really noticable.
With 4" exhaust you are perfectly fine and it'll be capable of 500+ horsepower.
5" will slow down the exhaust gasses and have less back pressure so it won't perform as well on a lower hp truck, but not really noticable.
Logistics Pro
Joined: Oct 2008
Posts: 4,818
Likes: 1
From: Avilla, IN
True dat. I hate engine covers. lol. So if it's a PSD. It's pretty easy to know whether it's a psd or not. If it's a PSD then the front of your engine will look similar to this picture, but you won't have the extra pipes for the IC like my pic has and you won't have the regulator on the front. You will have a fuel bowl in the middle of the engine instead.
GT_350, you do not need a back plate like the CIA have on them.
GT_350, you do not need a back plate like the CIA have on them.
OP probably needs to turn up the IP on his IDI to build more boost to get the whine.
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Elder User
Joined: Jun 2010
Posts: 854
Likes: 0
From: Salisbury NC
well thats the problem with these old girls mines that idi motor in the pic max boost 15psi and there are no stud kits or anything for the 7.3 idi the only way to make boost is lowered compression to a stroker ratio which cost and the ip is a deffinant do easy power adder im tryin to help him get his whine mines gettin that 6637 for that reason and ill set him up with one also thnks guys
Junior User
Joined: Oct 2010
Posts: 61
Likes: 0
From: Washington PA
The easiest way is to do a custom intake... IDK if the 6637 intake setup we guys use on our strokers will work or not.... and a 3" downpipe with a 4" exhuast all the way out the back and she will whine pretty good.
haha
