hey guys I'm doing a big brother,little brother project with my 16 year old brother jesse and I have a few questions.well first off he wanted to do the 4.3 because not to many people have done it and I don't feel like he's ready for a V8 swap just yet.(not enough disipline with the lead foot) so what will I need other than the engine?I know I'll have to swap in a v8 tranny,it's a stick so that should be easier.So what else could I do? What's a good year of 4.3 to use?any help would be greatly appreciated.

 

come on guys,someone has to have some info on this.

 

You might check out some of the chevy s-10 forums, there's quite a few 2.8 to 4.3 swaps discussed over there. Here's a link S-Series.Org :: Index

If you do a search on thirdgen.org there are also quite a few similar questions about this swap (if you can sort through all of the "swap a V8 instead" - you've already explained why you don't want little bro' to have one yet).

You might look into a 3.4 swap too.

 

I know that on an M-van (Astro/Safari) they use a motor mount that offsets the position of the engine bolt holes 3 inches forwards; basicly you could do the same thing if you can move the mounts 3 inches or so back, or you could use a set of Astro swap mounts "backwards" probably. Electrical should be pretty darn easy, extend a few wires and check the pinout of your new and old ECM (if it's SD I'd imagine it'll be damn near identical just swap a few pins) The stock box that's preferred for M-van swaps is the 1227747 ECM. A bit on mods to these motors:
Most of the TBI 4.3Ls are 145hp stock, however check whatever vehicle you're looking at getting the motor from if the 8th digit is a "B" that is a HO motor that puts out about 175hp.
The CPI engines have a balance shaft type motor, but make 200hp. They have a good cam and decent heads, unlike the above mentioned engines. They used some TBI intakes on balance shafts, the way you know is there'll be a core plug in the bottom of the intake right in the middle of the engine where it'd hit say the balance shaft If you have a welder that does aluminum you could probably modify a stock TBI intake. You'd need to cut a chip for this motor though, the stock TBI one would be marginal with it IMO (the cam is 208/208 in the M-vans, most TBI are the same as the peanut cam)

Look in the JY for 1988 or earlier manifolds. some have a "tubular" style passenger side manifold, supposed to be worth 5-10hp. I'd also run the sanding drums through em a bit.
You could probably use a set of 229/200 headers for this motor, but your milage may vary.
make the FPR adjustable. How to do it home made is probably covered somewhere in the TBI tips section; these motors are tuned LEAN at WOT.
While the 92-95 have the best heads and a GREAT cam it's also CPI and a balance shaft motor so swapping a TBI intake onto one is implausible unless you find one without the core plug on the bottom (check "late model" vehicles that are TBI for this intake) Those stock short blocks came with about 200hp.
Bump the timing 4-6 degrees from base and run mid grade in it.

ED:found out that Summit makes Super Comp headers for an 80-81 Camaro and the 229, these should fit your 4.3L as well. Not sure if the change from second to third generation will be an issue, but figure I'd mention it.

 

As far as mounting....get a pair of V8 frame mounts. Stab the motor and transmission as a combination. Have a set of V8 motor mounts on the V6. With the transmission properly mounted in the crossmember, you'll easily see the appropriate holes on the frame to mount the frame mounts. The holes should already be there in the frame.

Are you going carbed or fuel injection? If you're going fuel injection, go with a 1996 or newer. These motors have the same Vortec head design as the V8's....and the fuel injection can be adapted using a Painless Wiring Harness specific for that application.

If your going carbed, get yourself a pair of those 1996 or newer heads. There cheap on eBay and use the proper Edelbrock 4bbl manifold to use these heads. Like the V8, they require a specific intake. You can mount this head/intake combo on any of the motors described by Drac0nic as well as the headers.

You need to use a V8 transmission with the proper V8 flywheel with respects to one piece or two piece.

PM me if you need clarification.

 

it's still a toss up whether we're going fuel injection or carbed.I was planning on a vortec head set up at least.do they make tbi manifold's for 4.3's with a vortec pattern?

 

hey man did you do this swap yet because i am curently in th eprocess of doing a 2.8 to 4.3 swap any info on how your doing would be helpful i have a 4.3l ho out of a 92 s-10 and im gonna try to swap bell housings so i can keep the stock five speed i dont think it should be too hard with the bell housings seeing as both vehicles have a borg-werner 5 speed and im gonna swap out computers so it should be a plug and play operation.

 

If you're running a NWC I wouldn't reccomend it personally, the stock base model 4.3L is rated at like 245 ft-lbs. That being said, the 4.3L is just a standard 350 bellhousing and the 350 flywheel should work.

 

The part number / description for the carbed Vortec 4.3 is Performer Vortec V6 #2114. I don't find one for the FI. You'll have to go with the stock set-up I'm guessing.

The Painless Wiring Harness part numbers for the 1996-1999 4.3 Throttle Body Injection are 60214 and 60215. The latter being a exactly like the other except longer.

 

I believe they make an adapter plate for square bore to TBI. That'd be the direction I'd go personally.

 

Like mentioned above it's common on the S10 fourms. Off hand I dont remember when exactly they switched mounting points on the 4.3. Some will bolt up to a V8 crossmember but most will not without the swap mounts. IMO you guys would be better off with a 3.4 swap since it all bolts in but if you go 4.3L it's all good.

 

While the 3.4 would be an easier swap due to it's sharing the same family of parts as the 2.8, the rewards are less. The 4.3 shares so much with the 350 smallblock V8, it's a shame not to tap into the advantages.

The "for instances" are as follows:

A 4.3 block can easily be made into four bolt main block by simply using 350 four bolt main caps and drilling the outer holes. After market splayed mains for a 350 can be used for even better bottom end control.

The ports from the 4.3 Vortec heads are the same as the desired V8 Vortec heads (L31) so the same flow numbers and modifications apply. The small metric rocker arm studs in the 4.3 Vortecs can be drilled out and tapped to use standard V8 studs allowing the use of a fully rollerized rocker.

The pistons for a 350 fit the 4.3 so your selection is huge and affordable.

Camshaft profiles for the 4.3 are similiar to a 350's and how they perform is similiar as well. This familiarity keeps a builder from having to guess at how profiles will work. Camshaft profiles for the 4.3 are almost as plentiful as a 350.

There are no aftermarket wiring kits to put 3.4's into any vehicle not already using one. Painless has at least two that allow the EFI installer to retrofit into any vehicle.

 

this is for a camaro right? the best engine for you to use is the 4.3 vortec
from a 92-94 s-10(CPI motor). you want the one with the BLACK intake
manifold, it is the highest output. best bet is a bravada or high option 4x4
blazer. the motor will drop right in, i have done twice before. mounts from V8 will not fit no matter what.
you need motor mounts from a g-body with 3.8 CHEVROLET (malibu) and exhaust manifolds from a 2WHEEL DRIVE s-10 (4x4 are not even close, the drivers side kicks out to clear drive shaft) the 4.3 vortec wiring harness
is too short to follow the original camaro harness path but you CAN reroute
it to go in just below ac box (above pass. side exhaust manifold). if the computer you use is for a 4L60-E then get a trans. from a 94-96? f-body or 92-98? 2wd s-10 and swap the tail housing. use the 4.3 vortec torque convertor it has a GREAT stall (around 2400 in my cutlass 4.3Vortec)
there should be no extending of engine/trans harness wires.
you will use the same drive shaft and trans mountas you already have and V8 camaro ac lines.
if you need any specific info or pics i can provide them.
i used a flowmaster 50 with full 3'' exhaust and it idles like a hot 327 vette,
and under power it doesn't sound like anything else.

 

 

hp output
the 4.3 tbi motor is rated at 150/160 hp @ 4000 rpm, 230ft/lbs @ 2800
4.3 Vortec 1992-1994/95 at 200 hp @ 4500 rpm, 260ft/lbs @ 3600
this is through 2.25'' exhaust (ASTROs have 2.5'')with a cat. and a very quiet muffler.