Caught up on your swap, and really digging the 8.1L upgrade plan. Neat/clean execution, too.
David
David
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.
Hey thanks sir. That means a lot coming from someone that I view as a well executed perfectionist.
Can you cut down the first piece so it's closer to the throttle body? That would pull the whole thing down some.
Seems like it's going to hit the fan if it runs down much more but that might be the perspective of the photo.
Seems like it's going to hit the fan if it runs down much more but that might be the perspective of the photo.
That's a thought too!
I thought I remember reading that there was a set up off a van or heavier duty truck that had the outlet coming out @ 0 degrees instead of 45. I did a quick search on Larry's 8.1 tread and didn't find it but my search skills would get a D- if I was lucky.
Larry used a shorter 90° elbow since he's running the L29 cable throttle with the throttle body spacer. So his setup puts it 3/4" closer to the hood than the drive by wire throttle would be.
Just to illustrate how close his is, the elbow does rub on the hood slightly when closed on his '89 suburban. This isn't the case on his '78 K10 as the hood on the round eye front clip don't drop down like the '81 and later hoods do. If I remember right he used a silicone elbow instead of a metal or plastic one. It's a Spectre part for sure. And yes it's in the 8.1 thread.
Just to illustrate how close his is, the elbow does rub on the hood slightly when closed on his '89 suburban. This isn't the case on his '78 K10 as the hood on the round eye front clip don't drop down like the '81 and later hoods do. If I remember right he used a silicone elbow instead of a metal or plastic one. It's a Spectre part for sure. And yes it's in the 8.1 thread.
Found it.
Air Induction Pipe:
This one was a real PITA. For the first few years I used a stock Silverado air intake pipe which looked like poop. I had helped another guy (Blake H) on the 67-72chevytruck forum where he figured out a pretty nice concoction of Spectre air intake pieces to fit the 8.1L he swapped into his '86 2wd Crew Cab.
I cannot find the my Summit Racing invoice that lists the part numbers I used when I redid the air intake but here is Blake’s list. I pretty much copied all of Blake's pieces except I used a K&N filter.
Spectre Performance part numbers:
1 x 9781 4" Rubber 90 (throttle body)
1 x 9799 4" 90
1 x 9831 Filter housing
1 x 9729 4" 22 degree pipe that goes over the alternator.
1 x 990003 Adapter for the stock MAF Sensor
4 x 9771 4" coupler
All those part numbers cobbled together look something like this. I also used a Spectre bracket that connects to the alternator bracket to one of the large hose clamps to add support to the long pipe from flopping around but I cannot find the part number
Here is a novelty item one of my buddies made for me. A classic "Keep Your GM Truck All GM" decal modernized with L18 info. This is mounted on the radiator support
Looks great!
@Rick Capito is running an elbow that looks like it gives a lot of clearance. I remember him and Larry talking about it but do not remember what thread it was on.
Tunnel ram.
Martin.
Martin.
I have a factory intake tube headed in from Omaha tomorrow from work, so I’ll see what I can make fit.
Thanks dude! Yours next?
Haha once I figure out which one to put it in.
Whatever it takes! Haha I was actually thinking maybe a cowl hood would help enough.But that's probably the more expensive option versus a different layout. I'm pretty sure @Raggedy_Ann has the filter right on the throttle body, but he also has electric fans.
Running the filter straight off the TB means it has a speed density tune, and has eliminated the MAF. If he is still keeping the MAF thats a big no no. The MAF needs to be in a straight section of tube atleast 3" away from a bend. Otherwise the air flow model is off, and leads to weird drivability issues.
I don't know anything about that other than he has the HP tuner software and the harness and stuff were setup for his truck. He has a TH400 and doubler, but I know he put the VSS in the NP205 tailshaft. I'll ask him if he has the MAF on there because he was having some sort of trouble that he was hoping to fix thru the HP tuner.
This is true. When I did my 8.1 swap, I did my own air intake setup from a couple different pieces I bought off spectra. I ended up putting my MAF sensor a little closer to the throttle body than what factory does. When I had my 8.1 tuned, my tuner found that and it was messing with idle and other things. He ended up having to mess with the MAF trims/maps/settings (whatever the heck you call them) to get it to where it was reading correctly being a little closer to the throttle body then normal. It was interesting to hear him talking about it as he was fixing it.
Transmission and new starter bolted up. Test fit the L29 manifolds. Nice fit so I will most likely run those. Wiring harness is supposed to be finished up next week.
So the L29 manifolds will clear the frame rails just fine and the outlet is in a usable location and it looks like they do not have any air injection ports either? My buddy has a pair he said he would give me and I was hoping they would work on my C30.
The LH manifold does have a large air bung. I’ll snag a picture tonight. But the location of the outlet is perfect.
Careful, as I learned with my crew cab, there are frame differences between the C and K trucks. For one the frame flange on the C truck was wider. At least compared to my buddy's 79 K30.
