JAP
In the Brig (Banned)
Haha. Im the same way. My phone changed turbos to turbid 3 different times after I correct it. It was so annoying.
When is 4" exhaust not enough??
- Thread starter SkySki Jason
- Start date
8inchstroker
New member
haha mine too.......i typed dobson, n it said condom:shocked:
SkySki Jason
New member
Thanks guys, thats exactly what I was looking for. Anxious to see what you learn Vanderchevy... 
opcorn:
opcorn:I think what is going to be found out is that a tight 90 degree turn creates considerable restriction.
Without a increase in down pipe size decreases in pressure at the turbo outlet will be negligible would be my guess at what will be found.
In doing some reading in a few turbo books etc it seems the ideal shape at the turbine discharge port is bell or trumpet shape then continue that size on out. The reason stated for the shape is to cause a break up of the flow to create less back pressure.
How I saw the examples assuming a 4" discharge port would be to flare up to 5", then in our trucks, turn down the 90 and on out the back. Issue is room. Maybe it can be done with a 3" body lift.
Without a increase in down pipe size decreases in pressure at the turbo outlet will be negligible would be my guess at what will be found.
In doing some reading in a few turbo books etc it seems the ideal shape at the turbine discharge port is bell or trumpet shape then continue that size on out. The reason stated for the shape is to cause a break up of the flow to create less back pressure.
How I saw the examples assuming a 4" discharge port would be to flare up to 5", then in our trucks, turn down the 90 and on out the back. Issue is room. Maybe it can be done with a 3" body lift.
vanderchevy18
New member
I get that. Good point. What I was thinking is that there are a few bends from the down pipe back to the stock exit. I am going to go with 5" just before the 90 going from vertical to horizontal at the bottom of the down pipe. The thinking I have is, each bend in the pipe slows the gasses during redirection of flow. By increasing size, the bends shouldn't cause quite the backpressure.
I already ordered the kit. If for no other reason than to keep from smoking out the other lane during staging at the track and keeping in accordance with pulling rules. Its really no big deal to do some testing to see if there is any side effect from doing it.
Thoughts?
I already ordered the kit. If for no other reason than to keep from smoking out the other lane during staging at the track and keeping in accordance with pulling rules. Its really no big deal to do some testing to see if there is any side effect from doing it.
Thoughts?
Last edited:
vanderchevy18
New member
Ok Jason. Here's my findings.
Drive pressure- no change
Spool up time- Barely even worth mentioning. Nothing 99% of people would notice. Hell, its probably in my head. Lol!
Egt's- I do notice a small difference. Just cruising there isn't a difference. However, full throttle going down the track I don't peg my gauge. Instead of 1600+ I get about 1550 or so. LOL Also it doesn't take as long to cool down after running it. Instead of waiting 3 minutes to cool down to 400* degrees, it only takes about a minute and a half.
Overall- Jakes kit is incredibly easy ti install and looks super clean. It just mounts with 4 bolts to the bed floor. No mounting bolts up high. It looks good and is very rigid. Its also incredibly well priced! You wont find just a stack pipe as cheap as his entire kit! That being said, I HATE IT!! Good lord is it ever loud!!! I am going to fix it later with a nifty little trick but that'll be for a later thread of its own.
Drive pressure- no change
Spool up time- Barely even worth mentioning. Nothing 99% of people would notice. Hell, its probably in my head. Lol!
Egt's- I do notice a small difference. Just cruising there isn't a difference. However, full throttle going down the track I don't peg my gauge. Instead of 1600+ I get about 1550 or so. LOL Also it doesn't take as long to cool down after running it. Instead of waiting 3 minutes to cool down to 400* degrees, it only takes about a minute and a half.
Overall- Jakes kit is incredibly easy ti install and looks super clean. It just mounts with 4 bolts to the bed floor. No mounting bolts up high. It looks good and is very rigid. Its also incredibly well priced! You wont find just a stack pipe as cheap as his entire kit! That being said, I HATE IT!! Good lord is it ever loud!!! I am going to fix it later with a nifty little trick but that'll be for a later thread of its own.
