Headers and hi flow up pipes
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It was about 150 on the top end, but it felt like the vanes on the turbo were "holding the truck back". After some fooling around with them the turbo hit like a ton of bricks. I had tried to do that befor headers but couldnt get it to. Maybe the extra flow was just too much for the vane settings I had???
Did they make a difference? YES, but I feel most of it was from the up-pipes, but I cant say that for sure since I havent tested just up-pipes. If I am correct about it, all the headers themselves did was allow me to drive around with no inner-fenderwells and look cool
EGT drop was 2-300deg. But we lost power. I think it's similar to turbo upgrades. If you put a big turbo on your truck you're gonna have to add fuel to make it work. So in before and after comparison they only help EGTs. They allow you to make power easier but then you're right back in the same boat. So yes, they'll make power. I believe and want to try a set on some good flowing heads and intake. I think for them to be a good deal every thing has to work together. You can have the best headers in the world, but with a plugged air filter they won't work. We saw this with the ford 7.3 powerstrokes. With porting the head it picked up 30% air flow. Put the manifolds on it was lower than stock. With our headers the flow rates came back up. You gotta put the horse before the cart.
Did you notice any difference between the two? I'm curious if Jerod used bigger tubing and found lower egt but a loss in power. Just a thought.
Not really any diff, since I think the up-pipes are the bottle neck. This is just a guess but I would say theres a diff in egts cuz they were not tested on the same trucks. Also I am very concervative when it comes to things like that, cuz I'm sick of seeing parts that say they will drop egts 200 but they only drop them 50 at the most, ie. some intakes. By the way, I didnt experiance any noticable power loss. I dont know anything about anyone elses headers, and this could be comparing apples to oranges here. I was trying to build something for a daily driver and not an all out max effort truck
Here's what I know to be true:
When we put a less restrictive downpipe on Wendy, it did not affect power 0-2800 rpm. After that, the higher the RPM, the more gain. IIRC, 9 rwhp at 3600.
I believe we will see the same thing on up pipes, and Y-bridges. 0-3200 is where the engine was designed to operate, and if we want higher RPM (more air per minute) we need to increase the flow of the tubes.
I bet Casper will show about 30 rwhp or more with riser pipes and log manifolds But I won't find out for years perhaps.
When we put a less restrictive downpipe on Wendy, it did not affect power 0-2800 rpm. After that, the higher the RPM, the more gain. IIRC, 9 rwhp at 3600.
I believe we will see the same thing on up pipes, and Y-bridges. 0-3200 is where the engine was designed to operate, and if we want higher RPM (more air per minute) we need to increase the flow of the tubes.
I bet Casper will show about 30 rwhp or more with riser pipes and log manifolds But I won't find out for years perhaps.
I want risers that would flow like a 2.125" dia tube. This means starting with a 2.75" and flatn'g it for clearance for the pass side and using 2.125 for the driver's side.
We now have wrong side dipsticks, so clearance is not as bad.
We now have wrong side dipsticks, so clearance is not as bad.
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I should clarify. We just moved the torque curve up higher. The bottom end did suffer some though. I cannot track down the dyno sheets. We moved shop last summer and I can't find a bunch of stuff. The truck we dynoed was an lly with dual cp3, ats a5000 and efi live tune. Seat of the pants the truck seemed to march a little harder at the higher rpm levels. But again it wasn't enough improvment to justify selling them.
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If we ever want to run 750rwhp on stock engines, we need to make our power from 3000-4500, and exhaust restriction is part of the equation. I've gotten the tuning so that ~800HP only needs 1090FTLB to get there, but the EGT's are nuts at 4400.
Headers and risers will help move the Dmax up to the next plateau. A stock Duramax could have more power potential than a stock Cummins engine before failure. We can run more boost than they can stock before we lift the heads. Only EGT's are holding us back now.
Headers and risers will help move the Dmax up to the next plateau. A stock Duramax could have more power potential than a stock Cummins engine before failure. We can run more boost than they can stock before we lift the heads. Only EGT's are holding us back now.
FYI, the tighest thing on the pass side for the up-pipe is a bracket that holds the egr cooler. Take off the egr and that should open up lots of room. I was able to make a 2 1/4 by 1 7/8 up-pipe on the pass side with that bracket still on and the dipstick in place....I did modify the dipstick mount to push it up a little closer to the firewall tho. BUT it was a pita and would rather see all that stuff out of there.
I've gotten the tuning so that ~800HP only needs 1090FTLB to get there, but the EGT's are nuts at 4400.Please tell me you mean 2400
I've gotten the tuning so that ~800HP only needs 1090FTLB to get there, but the EGT's are nuts at 4400.Please tell me you mean 2400
4400 rpm not °F
Even with water injection, it's VERY hot after 4000.
I've gotten the tuning so that ~800HP only needs 1090FTLB to get there, but the EGT's are nuts at 4400.
4400 rpm not °F
Even with water injection, it's VERY hot after 4000.
Makes a little more sense to me now :rofl:
1650 on a dyno, higher on the track. Datalogging is screwing up still.
This is WITH water. Without water, it pegs the gauge.
This is WITH water. Without water, it pegs the gauge.