FLCJ8
Legacy Registered User
- City
- Palm Bay
- State
- FL
Meet Red, my 81 Restomod Build
- Thread starter Randyzzz
- Start date
- City
- Redmond
- State
- OR
The textbook answer is that it equalizes the exhaust flow between both banks creating smoother flow and more power.
My personal experience is that individual pipes create an uneven sound- almost like there is an occasional misfire. Even on 2 into 1 systems the exhaust pulses sound uneven. I think this is due to the firing order and even on 2 into 1 unequal length pipes cause uneven exhaust pulses. With the H-pipe, when 2 cylinders on the same bank fire one after the other, the extra pressure is equalized and the end result is a nice even rumble in the back. At least that’s my theory and I’m sticking to it!?
Edit: FLCJ8 and I must have been posting at the same time. His article sounds better than my rambling.
Belizeit
CJ-8 Member
- City
- River Ridge
- State
- La
Thanks for the response. I would like to see it played out with some clear pipes and maybe some special blue smoke coming out the right bank and a light yellow out the left and see this really happen. Seeing is really believing 
The equalize part I can fathom
The equalize part I can fathom
- City
- Redmond
- State
- OR
Thanks for the response. I would like to see it played out with some clear pipes and maybe some special blue smoke coming out the right bank and a light yellow out the left and see this really happen. Seeing is really believing
If it works according to plan, you would see green smoke out the back!?
I’ll let you know how it sounds once it’s running.
- City
- East Norriton
- State
- PA
There are also "X" pipe crossovers!
General consensus is H pipe for lower end power, X pipe for higher end power. I have an H pipe on my Mustang, I don't really remember X pipes being a thing when the exhaust was installed 25+ years ago.
General consensus is H pipe for lower end power, X pipe for higher end power. I have an H pipe on my Mustang, I don't really remember X pipes being a thing when the exhaust was installed 25+ years ago.
- City
- Crestwood
- State
- KY
Hey Randy I've been working on the body for awhile, but now back on drive train. Using Dave's motor mounts as well. Got the 5.3/NV4500 stabbed into place and will be using a Dana 300 xfer case. With "C" clamps I'm biased 13/16th to the drivers side and level front to back. It looks like my mounts are on the frame close to same location as yours. Have you set your final location on mounts yet? If so would you mind sharing where you ended up? Just wanting to see if I'm close or way off. Thanks, Brent.
- City
- Richmond
- State
- TX
Brentox,
What are you planning to use for the nv4500 to d300? I decided on using the np241c due to the adaptation issues, was just easier. Also allows the jeep to be flat towed for longer distances.
What are you planning to use for the nv4500 to d300? I decided on using the np241c due to the adaptation issues, was just easier. Also allows the jeep to be flat towed for longer distances.
- City
- Crestwood
- State
- KY
It's an early Dodge nv4500. IRrebuilt with a GM 10 spline input shaft, bearing retainer, and hydraulic throw out. The Dana 300 bolts right up to the Dodge NV 4500 no adapter required.
- City
- Redmond
- State
- OR
Measuring from the front edge of the frame to the front part of the frame mount, I’m sitting at 30 inches. I attached a couple of pics so you could verify points of reference. Once I was happy I drilled through the mounts in the forward stock bolt holes and ran a couple of bolts through. I’ll finish weld the mounts once the engine is back out. I ended up 1” to the drivers side. I wanted as much driveshaft to pan clearance as possible. I had to modify the drivers side mount bracket a bit to accommodate this position. (welded the slot shut and drilled where needed.) My engine also sat 3/8 low on the drivers side so I fixed that too while I was drilling the new hole. I leveled the trans pan so there is a 5* downward tilt to the whole powertrain. That’s how I’ve always done it and the 5* angle really helps with the rear C/V shaft angles.
Looking at your pic Brentox, your engine looks a bit further back than mine. Might just be the angle. I use the front edge of the body mount brackets as my limit line, that’s right about where the firewall falls. So I try to be a bit shy of that. I usually like at least an inch between the back of the heads and the firewall.
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- City
- Crestwood
- State
- KY
Thanks so much Randy. I am sitting further back than I would like. Did the first attempt when I didn't have the body on hand to transfer measurements. Now I've got it all back but work got in the way this weekend. Thanks for the 5* info as well. I did think level was optimal, but I thought I'd start there and tune it up. Thanks again for sharing your knowledge.
- City
- Redmond
- State
- OR
No problem. Glad to help. I dug through the "archives" (Dang Photobucket) and found a pic of where the engine was sitting in my Copper build. This is the best shot I could find, but I had it even further forward. I think you can see the body mount bracket in relation to the firewall in this pic.
Even in this position I had room for the stock mechanical fan and a shroud. These are modified MORE mounts that place the engine a bit lower too.
- City
- Redmond
- State
- OR
Zoom in- the Bellhouding /block seam is actually just behind or right in line with the spring rear bolt. (I had to do a outboard to fit the axle width). On my current build with the Dave’s mount it looks to be a couple inches in front of the body mount. About 1” behind the spring rear bolt. It’s hard to get things placed correctly with the body off. I remember on Copper I had the body on and off a couple times and ended up shifting the engine to accommodate the fan clutch. But the pic shows the final placement and I had about 1 inch between the fan clutch and the radiator. Here’s a pic currently looking straight down on the pass side- I can take a pic with a straight edge after work to confirm
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- City
- Crestwood
- State
- KY
That helps a bunch. I really do appreciate it. Don't mean to be a pain in the A$$.
- City
- Richmond
- State
- TX
Please, ask lots of questions! It not only helps you, but all of the others doing a similar swap.
- City
- Crestwood
- State
- KY
I just don't want to come off like I'm not willing to put in my own work. Hopefully I can return the favor.
- City
- Redmond
- State
- OR
No problem. I enjoy being able to help others out. That’s part of what makes documenting my builds so fulfilling. To be honest, I wish I lived somewhere closer to other Scrambler owners so that we could help each other in our builds.
I went out and took another picture with a straight edge. With the mounts in the position I told you in the first post, the back of the engine is 2” in front of the body mount bracket. (The straight edge in the picture is 2” wide. ) That places the back of the block 1 1/2” back of the spring hanger bolt. You should have a little under 2” firewall clearance on the passenger side with this placement. This is with the 5* tilt factored in. I’m thinking that the tilt might not matter as much with a manual trans but I’m worried about tunnel to trans clearance as is. I really don’t want a body lift...
Please ask if you have any more questions.
- City
- Crestwood
- State
- KY
That's what I'll setup this weekend. Then set the 5* up. I'm trying to avoid any body lift as well. Thanks again for the awesome pics.
