Vortec or not? U be the judge

[cfan10]

Does this engine look like a 5.3 or 5.7 it doesn't really look like a vortec to me. Interested in buying this truck but the owner does not know what the engine it is. The truck is a '70 chevy suburban with a vortec swap. Any advice is greatly appreciated.

[79Betty]

If it has the centerbolt valve covers and only 8 bolts for the intake it's vortec, i believe.

[anubisani]

Originally Posted by 79Betty

If it has the centerbolt valve covers and only 8 bolts for the intake it's vortec, i believe.

what this guy said is absolutely right.

[f.monroe]

Not a close enough pic but it sure looks like it could be a vortex engine.
Frank

[Ziegelsteinfaust]

I have worked 60 hours so far this week, but my guess would be a LT-1 350. Plus one of the kits I was shopping on a LT-1 swap used that type of accessory arrangement.

350 or 305 Vortec engines do not use that type of water neck. Rather TBI or Vortec headed Vortec engines. 88-97 trucks, or 04 Vans.

LS series Vortec or just LS series engines can not use what appear to me to be Ram Horns.

[f.monroe]

Originally Posted by Ziegelsteinfaust

I have worked 60 hours so far this week, but my guess would be a LT-1 350. Plus one of the kits I was shopping on a LT-1 swap used that type of accessory arrangement.

350 or 305 Vortec engines do not use that type of water neck. Rather TBI or Vortec headed Vortec engines. 88-97 trucks, or 04 Vans.

LS series Vortec or just LS series engines can not use what appear to me to be Ram Horns.

Nice catch on spotting the water pump assembly. I didn't notice it looking at the pic on my phone.
Frank

[csdineley]

Hard to tell from the Picture. But here's the Vortec 5.7 when I was putting it in my truck earlier this year.

Doesn't look like an Ls 5.3 to me. No coil packs and the valve covers look like center bolt style.

[csdineley]

Then again, I found this pic on the forums. So I think Ziegelsteinfaust is right LT-1

[BigBlocksRule]

Get the casting number off of the tranny ledge on the driver's side of the block and post it here.

[95 S_Trucker]

Center bolt valve covers started with tbi in 87. vortec was 96-00 and used 8 bolts to attach the intake manifold. The engine in the first pic looks like an lt1 with the water outlet/waterpump

[cfan10]

LT1 brings value down substantially, doesn't it? (asking price is 5k) Vs. Vortec 5.7, 5.3...what are the benefits with lt1 vs. stock engine, didn't most 1970 burbs come with a 350?

[silverbear]

Look at the intake manifold bolts. If the bolts are angled towards the head then they are most likely just center bolt valve covers. If the bolts are pointed straight towards the ground then is should have the Vortec heads. I discovered this a few years back when trying to install a older aluminum intake on a Vortec engine.

Judging from what I can see in your original post, that is a 350 (5.7L) and not a Gen III 5.3L. The 350 will have a distributor on the back of the intake. The 5.3L does not because it uses coil packs.

[cfan10]

Hey, guys found out that it is def a lt1 guy talked to po...question is he's come down to 4k cash...how many miles are too many? Is that a fair deal?

[meatwagon83]

not an lt1 either, the lt1 has the optispark distributor behind the waterpump, that is just a centerbolt 5.7 with a serpentine setup on it, and it looks aftermarket

[95 S_Trucker]

Originally Posted by meatwagon83

not an lt1 either, the lt1 has the optispark distributor behind the waterpump, that is just a centerbolt 5.7 with a serpentine setup on it, and it looks aftermarket

from the factory it would have an lt1 specific manifold without a distributor, it would have a oil pump drive and that's it.

With a different manifold, you can run an hei dist. a lot easier to work on than optispark.

[meatwagon83]

Originally Posted by 95 S_Trucker

from the factory it would have an lt1 specific manifold without a distributor, it would have a oil pump drive and that's it.

With a different manifold, you can run an hei dist. a lot easier to work on than optispark.

true, but dont lt1s have a reverse flow coolant path as well? but guess you could change the water pump too

[TrybalRage]

Yes, LT1s have the reverse coolant, with the crossover tube from head to head at the back of the motor. They can be modified to run carbureter/HEI distributor.

If you get rid of the optispark, you've essentially gotten rid of that engine's weakest point. LT1s are solid motors that can run higher compression due to the reverse cooling.

That would not scare me away at all. I've owned two 200K+ mileage LT1 cars.

[Ziegelsteinfaust]

The LT1 uses a distributor built in to the water pump, but it can easily be removed. I heard a large freeze plug works good. They still have the factory gear on the cam for a distributor.

Yes they are reverse cooled, but GMPP still has a carb'd manifold for them.

The best part about them is they are good for almost 350 hp with a carb set-up, and full bolt-ons. Depending on condition of the motor you start with, and which version too. Iron headed ones flow more cfm then aluminum other then LT-4.

A cheap build for a Vortec headed 350 is to use any of the LT-1 series cams, and they can be good for 330+hp with out a loss of torque. When I was shopping LT-1's or a Vortec build I would of used the B body cam for a touch more low-end.

[meatwagon83]

Originally Posted by Ziegelsteinfaust

I would of used the B body cam for a touch more low-end.

is that the cam from the 91c cars?

[rfmaster]

Originally Posted by meatwagon83

is that the cam from the 91c cars?

Any Y or F body LT1 cam will be a significant improvement over vortec or even 9C1 cam, just have to replace or trim dowel pin:

Vortec L31 cam (GM #10241264) 96 to 01
191/196 0.050 duration; 0.414/0.428 Lift; LSA 111

Factory LTx Camshaft Specifications:
1992 Y-body: 205/207 0.451/0.450 lift 117 LSA
1993-1995 Y-body, F-body: 202/207 0.450/0.460 lift 116 LSA
1994-1996 B-bodies (including L99 4.3L): 191/196 0.418/0.430 lift 111 LSA
1996 Y-body, 1996-1997 F-body: 200/207 0.447/0.459 lift 117 LSA
1996 Y-body, F-body LT4: 203/210 0.476/0.479 lift 115 LSA