FWIW, I've had 2.25 or 2.5" pipe between my frame and T-case for like 14 years. Stock carb fuel lines in the rail for a lot of that time and TBI/TPI lines since 2006. No heat shield and no problems.
CK5
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Headers vs. manifold
- Thread starter Mastiff
- Start date
Did you run steel or flex? In my case I used the existing steel up to the tcase area, then ran flex up the transmission brace. I'm not very happy with it but haven't come up with an alternative I like a lot better.
I ran stock TBI lines from the tank up the inside of the frame rail. Then it transitions to teflon/braided flex line somewhere up front - don't remember exactly where, but if you used the whole TBI line it might be in the same place.
Can you explain or show a pic of how the lines route from the frame rail to the TB?
Also, do you know what year factory lines you used? IIRC, the last years ran the fuel on the driver's side. Hmm, maybe I'd be ahead to copy factory routing on that side. I ignorantly got a sending unit from 1991 and it aims toward the driver's side anyway.
All truck factory lines were passenger side that I'm aware of.
Edit: Can't really find any good pics online of the routing of the lines. Pretty much mirrors the brake lines up to the rear spring mount though IIRC, which is about where it transitions to flex lines up to the block/TBI.
Edit: Can't really find any good pics online of the routing of the lines. Pretty much mirrors the brake lines up to the rear spring mount though IIRC, which is about where it transitions to flex lines up to the block/TBI.
Hmm. I can't find confirmation for sure, but LMC only lists there pre-bent as good up to 89. Something different in 90-91?
Are there clamps at the firewall or something to keep the lines off the pipes? I need to get under there to refresh my memory of how it's laid out, but it seems like the headers could be in the way.
Lines are clamped at the back of the head. Factory lines from frame rail to TBI are one-piece (hard and flex crimped together)...one part is flex, the part that is clamped, up to TBI, is solid.
I guess no reason they couldn't have run the lines up the other side, but AFAIK the sending unit for say, a K5 is the same from 1987-1991, and that would pretty much require the lines to run up the passenger side.
Would probably also introduce all sorts of problems with the throttle cable brackets and what not.
I guess no reason they couldn't have run the lines up the other side, but AFAIK the sending unit for say, a K5 is the same from 1987-1991, and that would pretty much require the lines to run up the passenger side.
Would probably also introduce all sorts of problems with the throttle cable brackets and what not.
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Can you explain or show a pic of how the lines route from the frame rail to the TB?
Also, do you know what year factory lines you used? IIRC, the last years ran the fuel on the driver's side. Hmm, maybe I'd be ahead to copy factory routing on that side. I ignorantly got a sending unit from 1991 and it aims toward the driver's side anyway.
Well I don't have a TB. My TPI fuel rail fittings are kind of behind the water pump. I had a buddy working in a hydraulic shop at the time and we made the lines up custom. The stuff from the tank and rails was from a 1990 K5.
All TBI lines run up the passenger frame rail, and up the back of the block. My 1990 V10 Suburban has dual exhaust running next to it with no heat shield.
Martin
Martin
Here's a bunch of pics of my situation finally.
I have dual 3" that I ran all the way back and dumped out the sides behind the rear tires, if I can fit dual 3" you should have no problem fitting dual 2.5" or something. I did put some heat sheathing around the fuel lines in a couple areas that were close.
I need to reroute my fuel to pull that off, and I can't quite picture how it's gonna go. The third pic shows how the header is right there at the spot in front of the shackle where, I think, the factory routing goes up. Right now I'm running it up the back of the trans and it totally interferes with pipe routing beside the tcase.
My fuel filter is further back closer to the tank, so I only have a supply and return line there, and in that specific area where everything squeezes but the Tcase, I did put some heat reflective sheathing around the lines.
I had true duals, then switched to a single muffler with dual in/out. So there is a pipe on both sides of the transfer case, then it crosses over behind the T-case. It is pretty tight between the NP208 and frame on the PS with the 2.5" pipe, so it is actually flattened just a little in that section.
Bringing this back up. I'm clearing a path on the passenger side (rerouting fuel lines) and hope to be able to run a pipe beside the t-case. Do you have any more pics of this setup? I'm not sure the best way to crossover behind the t-case. It looks like you went close here, so if the case ever needs to come off, you need to cut off the pipes? Further back though, and there may be no space for the muffler. Why did you switch from full duals?
I switched from full dual to make room for the anti-wrap bar. Even with the full dual, there was always a crossover pipe under the T-case yoke. To pull the T-case, I just unbolt the exhaust at the header collectors and un-fasten some hangers and slide the whole tailpipe/muffler assembly backwards a few inches or whatever's needed.
Crossover is optional with full dual, right? What's the benefit of it?
I'd be surprised if I could get the pipes apart at the flange without major headaches. It looks pretty heavily glued together by age and gasket/sealant. I hope not to have to take the T-case down for a long time, but you never know.
A crossover evens out exhaust pulses. It is better for performance, by it does change that uneven dual exhaust tone.
Martin
Martin
texlurch
Old fart on a hill
Since the tcase mount drops down, why not route the exhaust outside of it, under the frame...
yeah, you would see it, but it wouldn't hang lower or be in the way of the front shaft.
yeah, you would see it, but it wouldn't hang lower or be in the way of the front shaft.
I have it like that in the front now and the front shaft hits it. Are you talking about for the crossover? The t-case hangs below the crossmember in back, so the pipe would have to be very low, the lowest hanging thing under the truck.
If you mean not going right beside the t-case at all, it just seems too low. Seems like the first place that would hit in a lot of cases.
skyhigh4by
1/2 ton status
Mine is just like Blue85 how the y-pipe is on the D-side just past the T-case but with dual 2.5" inlet and single 3" outlet muffler. I have the cheap flow tech long tubes so instead of dealing with the crappy flange I cut it right off and welded 3"-2.5" adapters right on then to exhaust. Doing that actually gave more clearance at the shackle as well.
