Man I’m itching to get this thing in. Kind of at a stand still until I sell some more off of this old drivetrain. And waiting on wiring harness.
CK5
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'86 Jimmy 4in Lift, 40’s, tons, 8.1 Swap- 700r4 said PNNNNN
- Thread starter GWeakland620
- Start date
This is not a dedicated trail rig, but does trailer to the destination usually. I am currently in the planning phase of doing a 52/56" spring swap, and getting back to being more road worthy.
Do you have water pump, cross over tube, and timing cover yet?
Nope.
No. Water pump is obviously easy, just go to the parts store. Crossover pipe and timing cover may be a bit harder to track down
I found the timing cover on Ebay for pretty cheap.
Put a battery in the truck and the pos fired right up. It’s never done that in the 4 years I’ve owned it. Oh well, good riddance. Efi comes off Saturday and then I’ll pull the rest soon. Still not 100% sold on the idea of selling this motor and trans. Would make a great donor to a 4x4 K series later down the road.
That's the road to becoming a parts hoarder.
beags86
Eastbound and Down
That's something I would do. Don't be like me Greg.That's the road to becoming a parts hoarder.
But hoarding is what got me to the big block, So is it really that bad?That's the road to becoming a parts hoarder.
But I like you.
What headers are you 8.1 guys running? I want to run shorties in hopes that my current exhaust may work, and for clearance. Are there any frame issues with shorties?
Any BBC header for a squarebody fits an 8.1. I can't remember what Larry put on the burb but they were pretty nice. Check the polar bear thread, I know they are in there.
Looks like Sanderson’s. Not terrible on price, and they don’t use gaskets, so that’s cool.
Flanges are nice and thick too.
I was really surprised he went with them on the burb considering the endless shit he gave me about the crappy headers that were on my 75. It was an attempt to make use of the raylar can he used in that one I think. Then the cam came out and a stock one went back in.
beags86
Eastbound and Down
Sanderson are good stuff. The hot rodders have known about them forever.
They cost to much for me. And I don't think they give you the best flow either.
But there is a market.
They cost to much for me. And I don't think they give you the best flow either.
But there is a market.
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I purchased headers off summit racing that were designed for a mid-80's 454. Mine are mid-length cheaper Headman Headers. They're ok. I do have a small leak but it doesn't bother me too much. I may later on down the road re-do my exhaust and go with a nicer Sanderson header. But just as mentioned above, any old 454 header will fit in the 8.1 just fine. So you have plenty of options.
They clear the frame just fine. Mine were really close to the frame on the passenger side. I ended up shaving the frame down just a tiny bit to clear a few more milometers just for good measure. But you really don't have to
They clear the frame just fine. Mine were really close to the frame on the passenger side. I ended up shaving the frame down just a tiny bit to clear a few more milometers just for good measure. But you really don't have to
beags86
Eastbound and Down
Ok so the dude came and took the efi. While we were under the truck removing the wiring harness, he asked about my exhaust. Well I told him I’d sell the manifolds cheap, but wasn’t sure about the rest of the exhaust. So my 2 questions are:
1. What size of exhaust is this 8.1 going to require?
2. If I do sell the exhaust, what is my system worth?
1. What size of exhaust is this 8.1 going to require?
2. If I do sell the exhaust, what is my system worth?
4” turbo back. Just get a diesel exhaust and use it. It’ll be easier to hook up to the teriyaki Terror turbski.
2.25" full duals or 2.5" full duals or 3" single.
I think beags put up a link for an exhaust flow calculator some time ago. I put the stats in for my current system with the stock 8.1 hp/tq numbers and the 2.25" duals was adequate for it. 2.5" is probably the sweet spot. Anything bigger as duals and you have packaging issues.
I think beags put up a link for an exhaust flow calculator some time ago. I put the stats in for my current system with the stock 8.1 hp/tq numbers and the 2.25" duals was adequate for it. 2.5" is probably the sweet spot. Anything bigger as duals and you have packaging issues.
