1985 LB9 TPI plug wire boots - 2 straight and the rest 90s?
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Car: 1985 IROC Z w/19D Conteur Int
Engine: LB9 305 TPI
Transmission: MD8 700-R4 Auto
Axle/Gears: GU6 3.42
1985 LB9 TPI plug wire boots - 2 straight and the rest 90s?
Bought a replacement set of "OEM-style" ignition wires for my 1985 IROC with 305 TPI. Two of the wires have straight boots and the rest are 90 degree boots. Anyone know for sure if this matches original, and if so which cylinders get the straight boots? Can't go by what's installed now because they are replacements from a previous owner and are a mess. Thanks.
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Car: 1 Owner 1986 TA with a WS6 package
Engine: 5.0 EFI
Transmission: THM700R4
Axle/Gears: 277 Posi Speedo
Re: 1985 LB9 TPI plug wire boots - 2 straight and the rest 90s?
IIRC, weren't OEM numbered
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Car: 1989-92 FORMULA350 305 92 Hawkclone
Engine: 4++,350 & 305 CIs
Transmission: 700R4 4800 vig 18th700R4 t56 ZF6 T5
Axle/Gears: 3.70 9"ford alum chunk,dana44,9bolt
Re: 1985 LB9 TPI plug wire boots - 2 straight and the rest 90s?
Was looking for a display tpi pix but I've seemed to mis-placed them.
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Car: 1985 IROC Z w/19D Conteur Int
Engine: LB9 305 TPI
Transmission: MD8 700-R4 Auto
Axle/Gears: GU6 3.42
Re: 1985 LB9 TPI plug wire boots - 2 straight and the rest 90s?
Thanks gents. I looked all over for TPi engine pics too. Hard to believe there's nothing out there.
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Car: 1985 IROC Z w/19D Conteur Int
Engine: LB9 305 TPI
Transmission: MD8 700-R4 Auto
Axle/Gears: GU6 3.42
Re: 1985 LB9 TPI plug wire boots - 2 straight and the rest 90s?
Thanks Tuned Performance. Looks like the 2nd boot from the left could be a straight boot but hard to tell definitively. I know the rightmost wire in the pic (rear of eng) gets the heat shield (#26) and the heat shield is shaped to accommodate a 90. I believe that much is the same on the RH side. Still stumped.
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#9
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Re: 1985 LB9 TPI plug wire boots - 2 straight and the rest 90s?
Funny... 1986 Assembly Manual shows #3 with a straight boot, but nothing on the even bank.
The 87 and 91 Service Manuals show straight boots on #5, #6, and #8. The 91 Manual says "typical V8" while the 87 calls out specifically LG4, LB9, and L98. Both diagrams are similar, but they show specific details like the emissions piping routed correctly (differently) for their years.
I know that from 86-87 GM switched from 8mm wires and the large coil-in-cap distributor to the divorced coil distributor and 7mm wires. Looks like the plug wire clips and maybe the heat shields changed too. I don't really feel up to digging into it further, at the moment. When you lay them in place, you'll know if you need a straight or 90* boot depending how they clear the manifold and heat shields.
Edit: Forgot to mention, 86-earlier spark plug wire sets have 2 straight boots, 87-92 sets have three. Which explains the diagrams.
The 87 and 91 Service Manuals show straight boots on #5, #6, and #8. The 91 Manual says "typical V8" while the 87 calls out specifically LG4, LB9, and L98. Both diagrams are similar, but they show specific details like the emissions piping routed correctly (differently) for their years.
I know that from 86-87 GM switched from 8mm wires and the large coil-in-cap distributor to the divorced coil distributor and 7mm wires. Looks like the plug wire clips and maybe the heat shields changed too. I don't really feel up to digging into it further, at the moment. When you lay them in place, you'll know if you need a straight or 90* boot depending how they clear the manifold and heat shields.
Edit: Forgot to mention, 86-earlier spark plug wire sets have 2 straight boots, 87-92 sets have three. Which explains the diagrams.
Last edited by Drew; 02-01-2018 at 05:17 PM.
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Car: 1985 IROC Z w/19D Conteur Int
Engine: LB9 305 TPI
Transmission: MD8 700-R4 Auto
Axle/Gears: GU6 3.42
Re: 1985 LB9 TPI plug wire boots - 2 straight and the rest 90s?
Thanks again Drew. Should be enough to get me through. Appreciate it!
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Car: 1985 IROC Z w/19D Conteur Int
Engine: LB9 305 TPI
Transmission: MD8 700-R4 Auto
Axle/Gears: GU6 3.42
Re: 1985 LB9 TPI plug wire boots - 2 straight and the rest 90s?
... I found an '85 service manual with this pic. Looks like both straight boots go on the passenger side - cylinders 4 & 2. Again, this is 305 TPI engine (LB9). Hopefully it will be helpful for future visitors to this thread!
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