TBI equipped Vortec Questions

[Jerrys1990]

Definitely false. I had a block cast in 1995, from a TBI Yukon that did not have the bosses as all. The block had the partial vin stamp for that Yukon on it. I have seen blocks without provisions at all, some that were not machined including tall lifter bores, some that were roller ready and others with OE roller cams. I was surprised when I opened the OE GM 350 TBI in my uncles 94 with him to find it was already roller cam equipped.

Wow! Ok then....GM confusing people since forever! I'm looking at both TBI engines (dirt cheap) and Vortec engines (cheap.) It helps that my best friend works at one of the bigger junkyards up here and has eyes on the inventory Looking for a decent core to begin building on and considering both options.

 

[98 Nitro]

Look for Caprice TBI engines as well, they were factory roller cam engines with flat top pistons.

 

[Erik the Awful]

I've heard of people using the spider as a template for tapping holes in the oil gallery in the lifter valley. Throw a little all-thread in there, put two nuts on it to lock it in place and space the spider up, and Bam! You have roller provisions. I haven't tried it, but I would do that before I'd run a flat-tappet cam.

 

[PlayingWithTBI]

I've heard of people using the spider as a template for tapping holes in the oil gallery in the lifter valley. Throw a little all-thread in there, put two nuts on it to lock it in place and space the spider up, and Bam! You have roller provisions. I haven't tried it, but I would do that before I'd run a flat-tappet cam.

Doesn't some of the flat tappet blocks come with too high lifter bosses for the dog bones too? The lifters don't stick out far enough...

 

[TylerZ281500]

Wow! Ok then....GM confusing people since forever! I'm looking at both TBI engines (dirt cheap) and Vortec engines (cheap.) It helps that my best friend works at one of the bigger junkyards up here and has eyes on the inventory Looking for a decent core to begin building on and considering both options.

i still vote you find an fbody lt1. betterish roller cam, aluminum heads, reverse flow but whatever, hoses are easy. which junkyard are you speaking of here?

just honesty here. in michigan the way people drive stuff and the stuff that ends up in yards, vortec heads are almost never usable when you get into it. they crack fairly simply and the cost involved to verify they are good has been a deterrant of mine for quite some time. i rarely use them anymore, better off buying new ones from sdpp or similar or just upgrading altogether.

i know your a hobbyist at heart and with a seperate engine to transplant i would almost consider and older carb heads, or even the tbi heads, pick them carefully as to not reduce compression and add some port work to the mix and any of those can perform decently. i scrapped so much of my stuff that i wish i could have given before i moved had i known youd get this truck

 

[L31MaxExpress]

i still vote you find an fbody lt1. betterish roller cam, aluminum heads, reverse flow but whatever, hoses are easy. which junkyard are you speaking of here?

Corvette LT1 or LT4 would be better. If I could have located the Corvette accessory setup for less than $1K, I would have had one in my 97 Van.

 

[TylerZ281500]

Corvette LT1 or LT4 would be better. If I could have located the Corvette accessory setup for less than $1K, I would have had one in my 97 Van.

sure but speaking about the yards near us any engine pullout at most pick and pulls is 250ish with accesorys, i never see c4's and if i do they are tpi still. ive plucked several sets of 113s off them for that reason. i cam across one lt4 and the yard knew what it was, it got plucked and sent to ebay.

 

[Schurkey]

I guess you'd use the head gasket as a template to drill the holes?

Not hugely helpful. That would give you the starting point, but the hole isn't "square" to the deck surface. It's angled, and you have to be precise because it has to intersect the lower hole drilled straight back from the water pump mounting surface.

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If I ever need to do this, I'll be welding-up a drill guide starting with an already-drilled block. Something to bolt to a few head-bolt holes, with a hardened tubular bushing to "steer" the drill bit.

Look for Caprice TBI engines as well, they were factory roller cam engines with flat top pistons.

I had a service replacement crate engine for a TBI Caprice (part number ended in "151") in my '88 K1500 for eighteen years, until the head gasket popped and blow-torched a gouge between cylinders 3 and 5. ZERO computer tuning, had "as stock" driveability with some minimal extra power.

 

[Jerrys1990]

i still vote you find an fbody lt1. betterish roller cam, aluminum heads, reverse flow but whatever, hoses are easy. which junkyard are you speaking of here?

just honesty here. in michigan the way people drive stuff and the stuff that ends up in yards, vortec heads are almost never usable when you get into it. they crack fairly simply and the cost involved to verify they are good has been a deterrant of mine for quite some time. i rarely use them anymore, better off buying new ones from sdpp or similar or just upgrading altogether.

i know your a hobbyist at heart and with a seperate engine to transplant i would almost consider and older carb heads, or even the tbi heads, pick them carefully as to not reduce compression and add some port work to the mix and any of those can perform decently. i scrapped so much of my stuff that i wish i could have given before i moved had i known youd get this truck

Good to see you on here, Ty! We will collaborate much, I'm sure. I have plenty of time to consider my options, since I have to cough up a big chunk of dough to fix my house first........

 

[Jerrys1990]

Not hugely helpful. That would give you the starting point, but the hole isn't "square" to the deck surface. It's angled, and you have to be precise because it has to intersect the lower hole drilled straight back from the water pump mounting surface.

You must be registered for see images attach

You must be registered for see images attach

You must be registered for see images attach

If I ever need to do this, I'll be welding-up a drill guide starting with an already-drilled block. Something to bolt to a few head-bolt holes, with a hardened tubular bushing to "steer" the drill bit.


I had a service replacement crate engine for a TBI Caprice (part number ended in "151") in my '88 K1500 for eighteen years, until the head gasket popped and blow-torched a gouge between cylinders 3 and 5. ZERO computer tuning, had "as stock" driveability with some minimal extra power.

Thank you for this.