What's new
CK5
Register an account today to become a member! Once signed in, you'll be able to participate on this site by adding your own topics and posts, as well as connect with other members.

engine ?'s

Wicked Wolf Auto

Wicked Wolf Auto

1/2 ton status
 Premium
Joined
Nov 1, 2002
Posts
2,122
Reaction score
194
Location
T-ville, ut.
two questions...I'm thinking about swapping out the engine in my 97 GMC 1/2 ton. I'm seeing alot of crate engines with vortec heads that are set up for carbs. Will these work as a direct swap with my EFI and still pass IM standards? And I've seen them all being listed (vortec and HIPO engines) as using a 86-00 block. I have a engine out of a 93 in the garage, could I have it rebuilt with vortec heads and drop it in or will I have problems?
 
I don't know the particulars of the emissions standards in your state, but I know in many places in the US, it is illegal to swap a fuel injected vehicle over to carb. Look into that before you do anything.

Is there a specific reason why you don't want to get another Vortec 350 to replace your current one? A Vortec shortblock would be pretty cheap, just re-use your injection system, accessories, exhaust etc. If all you replace is the shortblock and the heads, there shouldn't be any reason why you'd have to change anything with the fuel injection.
 
You should still pass emissions with a carb setup, but I would stick with the EFI. Much cheaper to buy a short block or even a long block.
 
are you swapping the engine because it's worn out or because you want to upgrade/modify? Do you have the 5.0 or 5.7 in there right now?
 
AFAIK the vortec's are only a 350. Also i think he was talking about buying a carb'ed vortec and swapping his injection onto it (at least that's what i read into his post). At any rate, if he wanted to swap his EFI for a carb then he needs to check with the emissions people in his state. Here in California you are allowed to upgrade (this means you can go from carb to FI) but not downgrade (from FI to carb). Here in California you also can swap to a larger engine but not a smaller engine (once again, upgrade only) but the swap must be of the same year or newer as the vehicle it's being swapped into.
 
Yeah, it's a little unclear as to what his intentions are.

All the chevy truck engines after '96 were vortec's, with the exception of the old body style vans that were still produced in the early model year, the 5.0 engine code was L30 and the 5.7 code was L31. Difference was that the 5.0 heads didn't have the optimized combustion chamber/intake port design. However, the vortec label applied primarily to the new two-piece intake manifold and the new induction system, and these were used on the 4.3L V6, the 5.0 and 5.7L, and the 7.4L.
 
4X4HIGH said:
AFAIK the vortec's are only a 350. Also i think he was talking about buying a carb'ed vortec and swapping his injection onto it (at least that's what i read into his post). At any rate, if he wanted to swap his EFI for a carb then he needs to check with the emissions people in his state. Here in California you are allowed to upgrade (this means you can go from carb to FI) but not downgrade (from FI to carb). Here in California you also can swap to a larger engine but not a smaller engine (once again, upgrade only) but the swap must be of the same year or newer as the vehicle it's being swapped into.
Click to expand...
We don't have the kinds of restrictions that Cali does, but I think you are right about his plans. If he is keeping the FI then it is just a matter of making sure the intake will bolt to the heads he is looking at.
 
lectric80 said:
We don't have the kinds of restrictions that Cali does, but I think you are right about his plans. If he is keeping the FI then it is just a matter of making sure the intake will bolt to the heads he is looking at.
Click to expand...

Not necessarily, the cam for a carb might not be correct for the ECM.
 
4X4HIGH said:
Not necessarily, the cam for a carb might not be correct for the ECM.
Click to expand...
True, at least without a burned chip. I would think that just picking up a long block that is designed for the vehicle would still be the cheapest route. If he is planning a larger engine, then it will probably require a custom FI chip to handle a larger engine, and may require larger injectors.
 
lectric80 said:
True, at least without a burned chip. I would think that just picking up a long block that is designed for the vehicle would still be the cheapest route. If he is planning a larger engine, then it will probably require a custom FI chip to handle a larger engine, and may require larger injectors.
Click to expand...

I'm in that boat right now as i type this. I am forced to finally installed the engine i built which is full roller and AFR headed using a 454 TBI unit. I'll need to have Brian at TBIchips burn me a custom chip. Once i'm done it will head to a chassis dyno for thew results of my engine build. At the crank through Desktop Dyno and also through the Comp cams Camquest 6 program the engine is showing to produce 392hp @ 4500rpm and 508ft. lbs torque @ 2000-4000rpm.
 
I am not intending to use a carb at all my intentions were to use either a crate that says it was for a carb application and put my MPFI on it or use the block I have out of 93 and put vortec heads and all of my current MPFI and acc. on it.
 
Wrench said:
are you swapping the engine because it's worn out or because you want to upgrade/modify? Do you have the 5.0 or 5.7 in there right now?
Click to expand...

The engine in my 97 and the one I have out of the 93 are both 5.7's mine is just getting tired. I've had the truck since it was new and now that I bought the wife a new car it looks like it will be a couple years before I get a new truck so I want a bit more power for towing
 
If you want to use your '93 block, you just need to bolt Vortec heads onto it to make everything else bolt up. However, with the '93 you still have a non-roller TBI cam, which is pretty small and would likely require reflashing the computer.
 
Wrench said:
If you want to use your '93 block, you just need to bolt Vortec heads onto it to make everything else bolt up. However, with the '93 you still have a non-roller TBI cam, which is pretty small and would likely require reflashing the computer.
Click to expand...


Would I still need a reflash if I put in a roller cam?
 
If you put in a roller cam, you also have to put in a roller lifter setup, and if you don't want to reflash your computer, you would have to make sure the cam matched your Vortec cam fairly closely. You might be able to use the cam and lifter setup out of the VOrtec block, provided that your '93 block has the bosses in the lifter valley for the lifter holddown spider. It's likely but not guaranteed, a lot of those blocks were machined for roller cams but not all of them.

Still seems like a lot of work for a fairly small return--changing the cam and heads on a block, then installing it in the truck, just to freshen it up a bit. I'm guessing you're hoping for a low $$$ project?
 
Low $$$ is right plus this is my daily driver so being able to build what I have and do a quick swap is a big plus.
 
Sounds good ;) First thing I'd do then is pop the intake manifold off the '93 block to see if it's machined for roller lifters or not. If it's not, then swapping the roller cam in means buying aftermarket roller lifters=lots of $$
 
You must log in or register to reply here.

Latest Posts

Top Bottom