[nickelsun692]

Just getting started on my 1991 S10. I've selected lots of future parts and maintenance items. At the top of my list is a performance engine rebuild with a change to Vortec heads. Does anyone know of any reason to not try this swap??


Added features:
None yet!
4.3 five speed SWB
great body, lousy interior

 

[sYkboY]

They will require modifications. There are several threads. Try some searching, if you haven't already. Intakes aren't the same/ they don't just bolt up, you may be able to mod the one you have or you could switch to an edelbrock intake and carb or get the injection with the heads.

 

[nickelsun692]

Thanks, I will keep looking. I'm going to somewhat follow a Hot Rod Magazine performance rebuild article however their engine had non-vortec heads. Everything I've read seems to say the vortec heads are much better. And yes I plan to use the new vortec performer intake. Now I'm wondering if the MSD distributor will seat correctly???

 

[meeh350]

depends on the year head......... CPIs were vortecs and had vortec heads........heck... vortec heads date back to the mid 80s....... they were vortec by definition but not what most people consider vortec now adays. ANY WAYS... early 92-93 CPI heads will bolt up to the 91 intake... just make sure its a 12 bolt head/intake surface and not an 8 bolt... the 8 bolts will require modifications to make them fit and these mods arn't reccomended

I have the CPI heads on my truck... I didn't notice ALOT of performance change but I did notice a smother power band and stronger mid range.

I would have to recommend waiting to put the CPI heads on when you rebuild your engine... make sure you get a cam made for the CPI heads and not for the old heads... the newer cam profile matches the heads alot better...... from what i understand, the vortec heads cant take much more lift or much more of a radical cam than they already have... so my point is just make sure the cam manufacturer knows that its goin in a motor with those heads.......

from my experience... if you have an intake made the same year as the heads they will bolt up....... they made TBI clean into the new body style......94 i believe is when they quit so there are tbi intakes for some of the newer heads

 

[bg's]

I believe it's the 96+ heads is where the bolt pattern changes. I'm going
for a set of CPI/Vortec for my 92 soon. I had a link once that had a
decent breakdown of the heads that can go on 1st Gens. It's here
on this forum a few wks back. A search will find it.

I should also say you could use the late 96+ heads as long as you
changed out the manifold to an Edelbrock 2114 or 2116, and used
a TBI adapt. That way you could go with Edelbrock's cam, or a
Comp, Crane, maybe even a Isky cam. I do think you'd need to get
a chip made up for this though, to optimize the performance parts.

 

[nickelsun692]

I've almost gone blind from trying to read the past threads regarding vortec heads, which is which, modification possibilities, disagreements of facts, etc. I've come to the conclusion that for me and my situation that a V8 swap is probably best. Building a performance 4.3 is simply to confusing and potentially expensive.I have the JTR S10 swap manual which I would recommend to anybody contemplating a V8 swap. Thanks for all the replys.

 

[bg's]

Yep there's a lot of stuff out there. Here's a site that may interest
you.

www.leeshightechtrucks.com

 

[meeh350]

I've almost gone blind from trying to read the past threads regarding vortec heads, which is which, modification possibilities, disagreements of facts, etc.

yeah..because too many people who dont know what they are talking about and yet post replys.... as stated above you can make a tbi 4.3 with vortec heads... its all about the right parts... if you seen the newer heads and compared them to your old ones you would see what all the confusion is about and its really stupid

 

[nickelsun692]

I will keep reading since I'm not in any rush. Our S10 is a project car, not a daily driver. I just wish that a quality shop/company offered mail order performance 4.3 engines. It would make my project a lot simplier and probably cheaper compared a V8 swap. Thanks to all that replied.

 

[964pt3]

All GM stuff people like to call Vortec, Vortec heads, you know the ones that flow the best are the 96+'s. Yes the current intake will not bolt up to it, but if you look at Edlebrocks site you'll find some marine and street intake that do bolt up, requires a new throttle body and doesnt come with EGR.

Even CFM-tech gets into the game with one, has a carb fitting or get and adapter to run a TBI.
http://www.cfm-tech.com/catalog/_ca...fold_for_chevrolet_96__vortec_4_3l_954542.htm

 

[meeh350]

I just wish that a quality shop/company offered mail order performance 4.3 engines. It would make my project a lot simplier and probably cheaper compared a V8 swap.

jegs, summit, edelbrock......... you name,, they sell it ussually for the 4.3.........they just dont put it in their catalogues often... i call ussually and you would be suprised what all they have...

I aggree with 964pt3 the newer the heads the better and there are parts out there to make them work...

as for being cheaper to build a 350... .yes and no...... yes its cheaper to get 400hp out of the 350 but you have to remember all the other parts you will need to do the swap... and plus you still need to dump money into the 350 to build it up... but if you are willing to do that, the 350 would be more impressive in the end...... with respect to the whole picture the 4.3 is alot cheaper to build up even though the end product isn't as potent as the SBC

 

[964pt3]

I just wish that a quality shop/company offered mail order performance 4.3 engines.

Suprised someone didnt jump in with this, but there are more, here's one

http://www.speedomotive.com/4.3 chevy v-6 street master.htm

 

[nickelsun692]

Thanks for the link to Speedomotive. To me it looks like a crate"delux" 350 vortec from GM would out perform the Speedomotive "fully assembled" combo and save $$ to boot...at least on the engine question by itself. My plan is to end up with a strong and dependable s10 that ocassionally "surprises" people.

 

[TruStinger]

Suprised someone didnt jump in with this, but there are more, here's one

http://www.speedomotive.com/4.3 chevy v-6 street master.htm

thanks alot i wish they put dyno charts on their for each engine tho