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View Full Version : '94 TBI 350--- factory roller capable????



rob
11-10-2006, 11:57 AM
looking to see if my '94 L05 (TBI 350) motor is roller capable.. I know that all '87-up blocks have the provisions to run the cam retainer plate, and the bosses in the lifter valley for the lifter retainer "spider"

but does my block have these holes drilled and tapped already? I HAD a '92 LO5 motor and it was not drilled, had all the provisions, but no holes.

the reason I ask is that I plan on putting a roller cam in it, but don't wanna waste my time taking the intake off, and messing with all the crap, if I can't just slide the cam in, and not drill anything (which I wouldn't do, unless I had the motor apart)

jeep45238
11-10-2006, 01:53 PM
You'll have to take the intake off either way, you wont' be able to just slide the cam in, since you'll have to drop in new lifters, a spider, and the lifter retainers to keep them from spinning.

You probably have the provisions, but I seriously doubt that they would drill/tap if it wasn't going to be a roller. Think of the extra cost to do supply the labor, drill it, thread it, and not use it....times several hundred thousand/million and you'll understand why.

I was able to score a vortec roller short block for $150. Hunt around a little bit.

chevydad
11-10-2006, 02:04 PM
watch on ebay for a complete roller set up from a lt1. they can go pretty cheap.

rob
11-10-2006, 03:52 PM
here's the twisted thing about it all:

the other day I took the intake off a '93 305 (LO3) motor, and, while it was a flat tappet cam, the 3 bosses in the lifter valley were drilled and tapped for the "spider"
but:

that '92 350 (LO5) motor I took apart, was a flat tappet motor, and, while having the bosses, they were not drilled and tapped.

I think you're missing what I'm getting at here, I realize that you have to remove the intake to put a cam in a motor, all pushrod motors- save for the LSx motors do you have to do this (hell, I've had the intake off my LT1 formula 15 times in the past 2 years)
what I'm saying is, I don't wanna tear in to this thing, and find that it doesn't have the holes drilled and tapped, then I would have wasted a day taking it apart, just to put it back together with nothing done to it--- and I'm not wasting my time by putting a flat tappet cam in this motor.
the dealer confirmed that it has a flat tapet cam in it, but could not specify whether the block had the holes in it or not.

Busted Knuckles
11-10-2006, 04:50 PM
They actually made engines with shorter cam bores that can't go roller. If it has the tall bores with machined flat tops and the bosses in the lifter valley, it's roller capable. What's the problem with drilling and tapping 3 holes?

Jake Wade
11-10-2006, 06:22 PM
There is no way to tell other than to see for yourself,I have seen 87-95 TBI trucks with blocks that were completly factory roller cam ready,ones that had the bosses but no holes and the ones that were strickley flat tappet...unless you wanted to go with a retro fit kit.

rob
11-11-2006, 01:29 AM
What's the problem with drilling and tapping 3 holes?

it's not so much the drilling and tapping that bothers me. it's the half-assing involved while doing it.. see, I'd also have to drill and tap the cam retainer plate bolt holes as well.. if it's any more work than just sliding the cam in, and bolting on the associated roller hardware, then I'd just assume wait till I rebuilt the motor to do such a thing...

Fast305
11-11-2006, 07:17 AM
There is no way to tell other than to see for yourself,I have seen 87-95 TBI trucks with blocks that were completly factory roller cam ready,ones that had the bosses but no holes and the ones that were strickley flat tappet...unless you wanted to go with a retro fit kit.

I have also seen some 1992-1995 Fullsize Vans and trucks with factory roller cams. My 1992 G20 350 that I put into my 1983 had a factory roller cam and my 1994 G20 305 had a factory roller cam. Walking around in the Junkyards I have also seen many factory roller 350s in trucks, vans, suvs. My uncles 1994 C1500 350 was a factory roller cam as well.

Fast305
11-11-2006, 07:20 AM
There is no way to tell other than to see for yourself,I have seen 87-95 TBI trucks with blocks that were completly factory roller cam ready,ones that had the bosses but no holes and the ones that were strickley flat tappet...unless you wanted to go with a retro fit kit.

I have also seen some 1992-1995 Fullsize Vans and trucks with factory roller cams. My 1992 G20 350 that I put into my 1983 had a factory roller cam and my 1994 G20 305 had a factory roller cam. Walking around in the Junkyards I have also seen many factory roller 350s in trucks, vans, suvs. My uncles 1994 C1500 350 was a factory roller cam as well.

One other thing, if you run across a late model TBI 350 crate engine, it uses a Vortec short block and all of the 880 blocks have roller provisions. Mine had a roller cam, HD 350 TBI like you would find in a C60 truck.

Jake Wade
11-12-2006, 06:17 PM
I have also seen some 1992-1995 Fullsize Vans and trucks with factory roller cams. My 1992 G20 350 that I put into my 1983 had a factory roller cam and my 1994 G20 305 had a factory roller cam. Walking around in the Junkyards I have also seen many factory roller 350s in trucks, vans, suvs. My uncles 1994 C1500 350 was a factory roller cam as well.

Your the only person I know/heard of that has seen this. The 50 plus TBI VIN K 350 truck engines I have been into all had flat tappets...every one of them.

Fast305
11-12-2006, 08:51 PM
Your the only person I know/heard of that has seen this. The 50 plus TBI VIN K 350 truck engines I have been into all had flat tappets...every one of them.

I have been into that many as well. Most are in G-series cut-aways, in otherwords School Buses. I have seen many others in the wrecking yards with factory roller cams.

If you don't believe me maybe you will believe Napa. Look at a 1992-1996 Fullsize G20 Sport Van with a 350 K vin engine and TBI. The factory cam is not an option, but 2 different performance hydraulic rollers are available for it. Come to think of it, I have not seen a 1992+ 305/350 TBI in a G20/G30 van that was not factory roller.

Next time I go to the Junkyard I am going with Digital Camera in hand. I will snap a picture of every roller cammed 305/350 Van/Truck that I see.

http://napaonline.com/masterpages/NOLMaster.aspx?PageId=430&CatId=10&SubCatId=2

Jake Wade
11-13-2006, 03:15 PM
My expierience with engines that cam in vans is pretty limited,two that I recall, both were flat tappet and pretty sure both were late 80's early 90's.

ss4ever
11-13-2006, 05:04 PM
There is no way to tell. You will not be able to tell until you have your intake off to see unless you feel like running a scope down through your engine ;)

Randy

95nProgress
11-13-2006, 08:13 PM
FYI my 95 was drilled and tapped, had a flat tapped cam in it too. You'll probably need to get the retainer plate and hardware from the dealer. You will also most likely have to clearance the block behind the cam sprocket if you go with a double roller.

Brian

SSCLONE1994
11-25-2006, 06:31 AM
okay I have a 94 w/350, can I put roller lifters in it and if I did what would be the benifit?

SSCLONE1994
11-25-2006, 06:34 AM
Okay I have a 94 5.7 350 and I don't know what it has. How can i find out and can I run roller lifters on my truck and should they be Mechanical or hydro?

jeep45238
11-25-2006, 07:30 AM
Peel out the intake manifold and see if there are 3 drilled/tapped bosses under it. If there are, then you can grab the OE equip. of a junker motor and stuff it in there and go.

If not, you're looking at conversion lifters.

For a daily driver, hydrualic lifters.

95nProgress
11-25-2006, 01:56 PM
yep, what jeep45238 said.


Also, you just can't add roller lifters to a flat tappet cam. The cam material is different. You need a cam that is compatible with roller lifters. And then you will need to make sure your distributor gear is compatible with the roller cam dizzy gear.

Brian

jeep45238
11-25-2006, 03:46 PM
The material isn't different, but the grind itself is. A flat tappen lobe has a slight angle ground into it, to spin the lifter in the bore. A roller cam lobe is ground flat.

tee-boy
06-06-2007, 02:35 PM
yep, what jeep45238 said.


Also, you just can't add roller lifters to a flat tappet cam. The cam material is different. You need a cam that is compatible with roller lifters. And then you will need to make sure your distributor gear is compatible with the roller cam dizzy gear.

Brian

There's no point in adding roller lifters w/o a roller cam. The whole point is to have option of cam profiles w/ more lift given a certain duration (only rollers can do that).