Melt-Down prevention / 5.7 engine swap

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Elbert

Elbert

Joined
Jul 20, 2006
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Location
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Ok..I'll post a pic up in a little bit. So I have a 5.7 vortec setting in my FJ60 with the ECM sitting on the drivers side fender-well...similar to how GM had the engine sitting in a 1999 or similar pickup/suv. My large wire bundle that (engine harnees) runs from the rear of the engine over across the driver side valve cover, and then over to the ECM. Well this is right over the driver's side exhaust manifold and so I'm looking for something to sheild heat off the wire harness. I do have home made heat shield over the EMC and fuseblock but looking for something to shield the wire harness itself. The wire bundle is close to something like a 2.5 inch hose or so.

Don't know whats out there right now, it would need to go over or wrap around the wire harness ...which is approx 4feet or so I'm guess in length in this area. Friend who works in commercial plant says they have some type of crap used to shield hydraulic lines...

Looking for ideas? I don't want my sparkling new wiring loom to melt in a sticky nasty mess on to my engine harness. Anyone seen anything like a wrap or some type of flexable heat shield tube? I have some heat shields on my spark plug boots that have worked very well (from napa) but others make similar...don't know if its nomex or what but works good.

Post up some links or ideas.
 
note the large wire bundle ...thats what I'm trying to protect.
20180428_160120.webp
20180502_185527.webp
 
Exhaust Wrap, Heat Shields, High Temp Insulation | Heatshield Products

Found this... I posted ..then googled :) Loom is there to avoid shorts to ground and hopefully mitigate wire rubbing metal or sharp objects. A good heat shield product might do all of this together and protect from heat.

don't know how crazy $$ the costs are...fore sure I need to do something where the radiated heat of the exhaust manifold makes everything within a foot or two...very toasty.

The angle of the pic makes the distance between the wire harness and the manifold look closer than it is...but even then it is fairly close and not much I can to about that with respect to re-location .

Heatshield Products at Summit Racing

links may help me and others....

the other part that seems important to me...is the product must be flexible to conform to the wiring harness and also of such a design that it does not damage the wires itself from having sharp edges or abrasive edges/surface...etc.
 
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I was going to suggest header wrap, but looks like you may have already got there. I'd say that plus a shield on the manifold should be about as good as you can get. Unless you want to fab another shield to go over that manifold to help block more of the radiant heat from moving upwards.

I'm not sure, but I know they make heat sleeves for spark plug wires and I think they also make generic sleeves that you might could look into also.
 
I used a heat shield tape from summit or jegs. its ugly so i put the plastic loom over it. ive had to replace the loom once but the heat tape is still good.
 
jynx said:
I was going to suggest header wrap, but looks like you may have already got there. I'd say that plus a shield on the manifold should be about as good as you can get. Unless you want to fab another shield to go over that manifold to help block more of the radiant heat from moving upwards.

I'm not sure, but I know they make heat sleeves for spark plug wires and I think they also make generic sleeves that you might could look into also.
Click to expand...

hard to see in the pics...but I do have "heat shields" on the spark plug boots as the ram's horn style manifolds will cook your spark plug boots otherwise. If I could find some material like this is in a larger tube that would be perfect. Header wrap was suggested too. Yeah I've thought about asking my friend to see if we can come up with a "better" heat shield on the ECM/fuse block. As you noted I'm not sure what would work regarding a heat shield on or near the manifold (some of that stuff gets to be more painful than anything), I might go looking around to see what's out there in the GM world, I do know the OEM type heat shields for the spark plugs that fit the 1999 5.7 cylinder heads don't align with the old school rams horn manifolds (but those heat sheilds ) only work for hte spark plugs and only work with the old school GM heads due to some minor issues with the bolt holes that do not align with the new heads. Some of the newer engines from GM have some nice metal heat sheilds that go over the spark plug boots ( i have some of those, just not used yet). And the old school spark plug heat shields that work with the rams horn manifolds don't work with my cylinder heads.

I think I'm just going to focus on some type of wrap or shielding material on the harness and look to see if we can make a better shield over the ECM/fusebox (the one I have is not shown in the pics) but however you slice it the wiring is close to the radiated heat coming off that manifold. Its a challenge to have something in this area that does not become its own problem due to the proximity of the radiating heat source heating the heat shield up too much and the shield becoming its on hot plate that melts anything that comes in contact....may need to look to see if I can isolate the heat shield I have...better between it and where the wire harness may touch it it (have some type of air-gap.. May just have to employ red-neck technology to see where I get. I'll post another pic over the week end to show the home-brewed heat shield for the ECM/fuse block.
 
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radioridge said:
I used a heat shield tape from summit or jegs. its ugly so i put the plastic loom over it. ive had to replace the loom once but the heat tape is still good.
Click to expand...

I need to check that out...I bought a large 2 inch loom section so I could likely do the same... I'm thinking the large loom right now might melt as we approach summer. Loom may come off on some area where heat is the strongest and I'll use header wrap or something to see what happens. If that plastic melts (loom) its going to be nasty and hard to clean up.

Effort is to avoid further wiring issue with the *&^#$ feed to the cam sensor and the resulting code that screws performance. Engine is currently running good with no codes.....I want it to stay that way as I have to screw with these other things that need to be fixed.
 
thanks for the feedback....at least I have my own mobile "microwave oven"....
 
Not sure how much you want to throw at it, but a set of 5.7 ceramic coated shorty headers, or look into having a set of the stock horns cerami-coated. That should drop temps across the board, but is going to be in the higher end of the price scale. Header wrap is probably going to be your best starting point
 
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