is there any difference in the 350 engines between the two? mainly the block?


also, what's the best way to tell a 350 from a 305 without the vin #??

 

I am pretty sure the engines are the same...As for telling a 5.7 from a 5.0..it is stamped on the block at the back by the distributor. It will either say 5.7L or 5.0L. Like I said though I am pretty sure they are the same HTH

Keiran

 

Same-zorz.

However - they may have different performance options.
And I ask out of curiousity why not go by VID? Easiest way IMO.

 

vid?? or vin?

there is no visible vin on the car......... both were stolen recoveries; i checked the easy spots so i just figured i'd get opinions rather then go in blinded incase anything was filed down.

 

You could always take off a head and measure the bore. If it is just about 4" or more even it is a 350, if it is a bit smaller...305

Keiran

 

If its an unalterd car, Take a look at the bcc on the PROM.

Among other things...

 

thanks for the replies.........

i guess i'm just looking for the quickest way as when i do go i typically don't have alot of time and pulling it completely apart wouldn't be practicle just to check that out. although if that's the only way then i guess there isn't much choice is there?

 

Like I said ..It should be stamped in the block, back by the distributor. It is on my 89 Iroc 5.7L.

Keiran

 

Check RPO codes too for LB9 or L98 to tell if its a 305 or 350, thats if it retains its stock factory equipped engine...

 

He can't check the rpo codes, if they are not there. being that both are theft recoveries the rpo codes are probably gone.

Keiran

 

Who'd take time to peel away the stickers inside the console or hatch area??? id think unless it was in water or fire they would be there but it would only help if it retained a stock engine. Just one more thing to look at when youre there, what can it hurt?

 

8th digit of vin code will be a 8 if it is a 350 car!!!

 

He has no VIN#'s. Must read prior posts! LOL!

 

woops..sorry about that .lol

 

t-tops? not a 350

 

the ta has t-tops so it very well could be and the z28 doesn't........it's a 92 with the purple and silver stripe package. interior is completely gutted so there are no rpo codes in the rear or on the doors and such.

it has the black valve covers on the engine and had the tpi equipment until i stripped that part.

forgot about checking the back of the block.......but other than that everything else has been filed down.

there is no way to tell with the heads is there since the valve covers are off on the z; i mainly want the 350 bare block if it's good.

not sure what to do with the ta.....i have to figure out a way to pull the engine quickly as they will be made into cubes shortly.

 

for gods sake, dont let them turn it into a cube!

 

Mine has them and its a legit L98 car. Perhaps you meant for 1991 the t-tops weren't available with the L98?

Dave

 

My 89 Iroc had T's and a 350....factory!

 

Dont the 350cid and yhe 305cid heads use different spark plugs? If that is the cas I guess that could be a way to check assuming the heads have never been altered.

 

On the block, pass side, right where head meets the block, on the small "shelf" below the valve cover.

There will be a 3 LETTER code in there if it hasn't been altered. That will tell you what year and body that engine came out of.

For example 'SNA' is the block stamping for a '87 L98 F-body


Post the code and I'll search 'em for you.


HTH

 

I heard in a different message board that you can call or go to the dealer and they will have your RPO's..91- present you can do this... oh but wait I bet u need a vin # sorry but if there was a way u could come up w/ it you could definatly go to the dealer

 

This method works most of the time:

Reach down and feel the harmonic balancer. If the back side is scalloped out (feels hollow on the back side) then it is definately a 305.

The 350 balancers were solid.

HOWEVER, some 305s (TPI engines---some) had solid balancers also.

I had an '88 GTA with a 305 that had the hollowed out balancer and have worked on many 305s with the hollowed out balncer.

I have yet to see a STOCK 350 with a hollowed out balancer.

Also, why not pull one of the valve covers and check the casting number there? Then check back here or at www.mortec.com ?

jms

 

starting in 90 no 350 cars had t-tops as far as i know. also, if its a 5-speed, its a 305

 

alright, pontiac cars could have 350 autos in any year with t-tops pretty much. it's only the chevy's that had the stupid rule.

i can't save them from getting crushed as most of them aren't to be bought.........the way police run things is a little screwy. i just get in and get what i can off the frame before someone else does and they take care of the rest. once in a great while one will go to auction. but very rarely.


if i take the valve covers off where would the casting be?

i'll also check where the head meets the block. these are alot of good ideas guys and i appreciate the info.

 

.

 

shouldn't the vin also be under the front or rear bumper? and in the storage thingy in the hatch area?

 

Where exactly under the bumper????

 

The block in my IROC was stamped with 5.0 between the drivers side head and the firewall. It's easy to see with the engine in the car. Just have to pull the wire/hoses out of the way. A flashlight may be handy if the hood is still on or if natural light is low.

Hodge

 

On my 89 Formula 350, there is a sticker on EVERY body panel with the VIN ## on it. Inside of both fenders, visible with the door open; underside of hood, on the rear hatch, on the inner side of the doors, on the radiator to front bumper panel, everywhere. Look at all your body parts, and you may find a VIN somewhere. Then you just have to wonder if it's the right VIN for the car. (Lotsa people use used fenders, doors, hatches, etc. for replacement)

 

That's because starting in 1991.....GM put to much torque in the 5.7 L98 Z28 Camaro's. If the 91 and 92 Z28's had t tops with 5.7's.....the car would actually twist. 1987-1990.....the IROC Z's with 5.7's had t tops because there was not as near as much torque as the 1991 and 1992 Z28 5.7 TPI L98....that's why your 89 Iroc has t tops.......even with the 5.7.

 

UMmm?? Yeah I already knew that. KagA152 on the other hand didn't. I was just letting him know he was wrong. I guess the right thing to have done, would 've been to tell him just what you said....but I didn't.

 

oh! no prob man...!! you have any pictures of your car posted on here?

 

actually i did know that. and didnt no t-tops on 350s start in 90, correct me if im wrong

 

The 90s didn't have T-tops either. 90-92 the cars had the same hp/tq ratios. When you look up the actual hp and torque numbers, they really don't change significantly.

87 IROC-Z Formula Trans Am GTA
A4 L98 V8 9.3:1 5.7 (350) 225@4400 330@2800 TPI
88
A4 L98 V8 9.3:1 5.7 (350) 230@4400 330@3200 TPI
89
A4 L98 V8 9.3:1 5.7 (350) 240@4400 345@3200 TPI
90-92 identical according to this info
A4 L98 V8 9.3:1 5.7 (350) 245@4400 345@3200 TPI

Check out some more numbers here. Maybe there is an error in there, but it won't be by much, I've still yet to see someone correct any of those numbers.

And why they stopped t-tops...I don't know. I'm sure the car actually twisted. But I can't see it twisting THAT much more. Maybe GM just realized that it was causing problems or it was a safety issue?

 

thanks for the suggestions guys i'll look over the block better!!


understand that their is no vin numbers on the car anywhere. there are no pannels whatsoever as well as no interior. there is a frame and odly enough a drivetrain.......minus wheels as it's laying on the frame. no radiator either.