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anyone drive a '86 k5 or 1/2ton?

mostwanted

1/2 ton status
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I am just curious if the 350 that came in that particular year was a gen 2 block or not. The PO had put a crate motor in with center bolt valve covers and there was no lob on the cam for a mechanical fuel pump. Is it possible that there were a few carberated trucks built with a electric pump in the tank?
 
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afaik, by the '88 model year, carbs were history in the gm regular production line.

my '94 c1500 (with 4.3L v6, not 5.7L v8) has center bolt valve covers and no provision for mech fuel pump.
 
My buddy has a 96 2wd 1500 with a 305. it's a vortech motor. 96 was the first year of vortechs I believe and I doubt any were made with carbs...
 
mostwanted, we haven't asked yet, but why do you want to put a carb on there? being an obd2 system, passing inspection could be really tricky, that way. it would be throwing codes all over the place unless you found a way to trick the computer, i would think. of course, you may have more relaxed standards than we do, here.

the stock engine's power should have been 255hp, with torque somewhere in the low 300's. and yes, that is the first year of the vortec v8. the vortec v6 was offered as an option, for a few years, prior.
 
if its not an LT1, LT4, or an L99, its not a Gen II small block. on a Gen II small block the water pump is driven by a shaft from the front of the cam, and has no pulley on it.

FWIW, even if it is a Vortec, it still has provisions for a mechanical fuel pump. swap in a cam with a fuel pump lobe and run it.
 
Maybe I was misunderstood? It came factory with a carb, Not TBI. I was just checking on what the chances were of GM putting a center bolt block in 1986 specifically or possibly fazing in a electric fuel pump.. We all know TBI was introduced on 1987 model.
 
Many of the factory crate motors come with centerbolt valve covers , and carbed intakes . Could of been bought last week , last year , or six years ago .

Point is , get the numbers off the block ,and we can know for sure :thumb:
 
GM was switching fuel pumps alot during this time frame.
I didn't do specific research for your engine, but when I re-built my '86 4.3l V6 in my c10, what i found was
1985: Elec. Fuel pump Carb, lobe on cam
1986 early - Tonawanda plant engines: Elec Fuel pump, carb, no lobe on cam
1986 early (Romulus plant only) mid-late (All): Mech FUel pump, carb
1987: Elec fuel pump, TBI, no lobe on cam

So GM was acutually using elec fuel pump or mechanical fuel pump in the thing, depending on where the engine was produced! Talk about silly.

So, it's definitly possible they used elec. fuel pumps on some v8 engines prior to 1987., I only found this information because a guy who worked at the Tonawanda plant making 4.3L engines during this time had a huge page on all the little differences in 4.3l V6 blocks and heads.
 
It could be possible, I have an 86 K-5 and its a funny transitioning year because the replacement motors for those trucks go from 1970 to 1985 and then start up again from 1987 to 1995 right before they switched to the vortech. My truck has an identical engine from the 87-95 era and my truck is still carbureted but uses that style motor.

Hopefully that all makes sense or you get what I'm trying to say
 
I just pulled a replacement 350 from my 86 K10 suburban that a PO had put in. It has a 1 piece rear main seal and old style heads (perimeter valve cover bolts). I think 86 was the first year for the 1 piece rear main seal but some (most? all?) 86's had the old heads.

Dave
 
86 was the first year for the 1 pc RMS
87 was the first year for the perimeter valve cover as previously stated.

FWIW, most TBI engines have fuel pump lobes on the cam. torn into alot of 87-93 Capices with TBI, stripping them for derby cars. we've actually got a couple TBI to Rochester 2 Jet adapters. slap a push rod in it and the proper cover, bolt on the fuel pump and go. same with 88-92 Chevy trucks.
 
My K5 had the 1 piece rear main, and the older heads, like chevy_addict. Like was said, 86 is the odd year for K5's.....old heads, new block. My ride was the full CCC/ESC system and had a mechanical fuel pump. The 8-95 crates will not come with the fuel pump eccentric, because there is no mechanical fuel pump to drive. My crate motor didn't even have the hole available for the pushrod anyway.
 
My '86 305 in my K10 has a one-piece rear main (new style block) but the old style heads with a CCC carb setup.
 
btolenti said:
My K5 had the 1 piece rear main, and the older heads, like chevy_addict. Like was said, 86 is the odd year for K5's.....old heads, new block. My ride was the full CCC/ESC system and had a mechanical fuel pump. The 8-95 crates will not come with the fuel pump eccentric, because there is no mechanical fuel pump to drive. My crate motor didn't even have the hole available for the pushrod anyway.

the hole wasnt even there? my Vortec has a hole for a pushrod, just a plate bolted on where the fu el pump would be. i'd almost bet that's what you've got too, seeing as the L31 shortblock is i dentical to the 87-95 5.7s.
 
pauly383 said:
Many of the factory crate motors come with centerbolt valve covers , and carbed intakes . Could of been bought last week , last year , or six years ago .

I am sure that this is the most logical explaination. I am changing out my distributor this weekend with a new MSD. I will jot down those numers.
 
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