V-8 swap questions

[mecwpri]

Been lurking in the 60-66 forum for a while as that project needed attention. I plan on swapping the 4.3 out of my 4 door blazer, 1991 vintage for the 5.7 out of a wrecked 89 or 90 van that I have. I plan to freshen the v-8 prior to install, my question is motor mounts, will the factory 4.3 work? seems everybody wants to sell 2.8 mounts and adapters, seems like a week setup to me. Also plan to use factory exhaust manifolds and remember reading somewhere that firebird are the desired ones? any help here? Will the ECM need work or will the van ECM work? how about the factory 4.3, will it work or what? I would like to keep all the factory accessories and factory look, dont want any bling, just more power.

[gchemist]

You can use the same motor mounts. Exhaust is a problem. Checkout this site for parts: http://www.s10v8.com/store/
You'll need a 5.7 PCM. You can order one from www.wait4meperformance.com

You'll find a ton of information here: http://www.s10v8.com/

[Scottshotrods]

check out www.scottshotrods.com
go to our scotts motor mounts section we do have motor mounts for your engine swap.
Justin
scotts hotrods

[2manyprojects]

I think the 4.3 mount sits the engine up higher for some reason. It doesn't cost anything to try it. You'll know as soon as you set it on the mounts if it will work or not. I flogged on 2.8 mounts in mine for 5 years with no problems. It's just a rubber mount it doesn't care what the engine is. Use 5.0 3rd gen F body manifolds, the 5.7 ones have clearance issues. If you decide to use headers get the thick flanges and ceramic coat. I didn't that was what I hated the most about mine. Use the van ecm. If the blazer is TBI the 4.3 harness should work, you might need to extend a few wires but no big deal. All the front accessories will bolt up they are probably the same as the van anyway. You will need an electric fan or move the radiator under the core support. A Taurus SHO fan works good if you go electric.

[v8blaze]

^ he pretty muched summed it up. I think the wires for the TBI unit will need to be extended but the rest should work fine. The acc. brackets will be the same. Ive got stock 4.3 acc. and water pump on my carb'd v8. Im also using the 2.8 frame mounts with the usual adapter mounts and ive had zero problems with about 2 years of regular driving.

[Dying2Live]

I've used both the 4.3 mounts and the 2.8 mounts, please use the 2.8 mounts, you won't regret it. The 4.3 mounts, as stated previously will sit the V8 at the same height as the 4.3, but you'll want it lower due to the front of the motor. The 2.8 mounts are actually stronger because they are fully incompassed in metal. The rubber on the 4.3 mounts will break after time and then you'll have a big ol V8 that's not being held down very great under the hood of your dime. Good luck on the swap, V8 S10's are fun it they are done correctly!!!!

[Myself]

I agree with the above. I have 2.8 mounts in mine and it has been a daily driver for 44,000 miles. Also been to the track a few times.

[blazer72]

NICE - I'm in the middle of a 2.8/4spd to 350/350T to my 86. Been on s10V8 constantly for 2 weeks researching.

I'm going with the corvette rad/elec fan kit they sell for $500 in the forward position, and I'm also modifying the core support and hood latch/bracket to put in the tripac condenser. In OKC, A.C. is an absolute must. I'm buying the manual from Jagsthatrun (JTR) and also the evaporator box plate on the heater box to make room for the rear passenger side head clearance.

I went with shorty headers for clearance issues.

I'm deleting the mechancial fuel pump and adding a fuel pressure reg. I'm undecided on the tilt column shift and the aftermarket floor cable shifter Hurst/B &M.

I was overwhelmed and apprehensive until I researched - now I'm just excited to take it for that first ride.

[Dying2Live]

Originally Posted by blazer72

NICE - I'm in the middle of a 2.8/4spd to 350/350T to my 86. Been on s10V8 constantly for 2 weeks researching.

I'm going with the corvette rad/elec fan kit they sell for $500 in the forward position, and I'm also modifying the core support and hood latch/bracket to put in the tripac condenser. In OKC, A.C. is an absolute must. I'm buying the manual from Jagsthatrun (JTR) and also the evaporator box plate on the heater box to make room for the rear passenger side head clearance.

I went with shorty headers for clearance issues.

I'm deleting the mechancial fuel pump and adding a fuel pressure reg. I'm undecided on the tilt column shift and the aftermarket floor cable shifter Hurst/B &M.

I was overwhelmed and apprehensive until I researched - now I'm just excited to take it for that first ride.

The Corvette radiator that they sell on JTR is good, I went with the one that they make for my truck, but I have a mechanical flex fan on mine. I will upgrade one day to the Taurus E-fan. I did mount it in the forward position and put the serpentine setup from the 4.3 on the front of the V8. On the JTR manual, they have quite a bit of info, but I honestly got alot more the information from the forums (S10forum.com). I did alot of research (about 6 months worth) acquiring parts, and figuring out what I wanted to do, but it honestly wasn't that hard. The exhaust shop didn't like me, but it's all good.

And depending on how you mount the motor, you may not need the evap box plate, i haven't on the 2 that I've done, but you never know. Good luck, and ask questions if you need too!!

[454_72_4X4]

Use v8 mounts. They're a million times better and easier to work with than the 2.8 conversion mounts. Any old mount out of a mid seventies car or truck will work. The clamshell type.
Some trucks use a taller shell so ya wanna stay away from those.
I think I've still got scans of motor mount adapter plates if ya need/want 'em.

Like someone above said, the 4.3 mounts are junk.

Alot of guys like the 2.8 mounts. I don't because they have the offset plate where the actual mount sits behind the mount bosses on the engine block. Just seems like it would pull at a strange angle on the engine block.

I used a custom 4 core rad from Superior radiator for my 87. It worked really well and is now 13 years old and as far as I know still working just fine.
It mounted inside the rad support and I used a 19" flex fan with a shroud I built. Also a long water pump and a 1-1/2" fan spacer.

I haven't made up my mind on which rad I wanna use on my Sonoma though. I want to keep the AC so I gotta have room for the condensor?, (condensor or evaporator?, can't remember which it is up front...LOL).

[Myself]

Mine originally had a 2.8 with a 4 speed auto. I made my own motor mounts to work with the stock 2.8 frame mounts. I'm using a 700R4 from a Trans Am, with a Painless wiring lock-up kit. It's sitting on the factory crossmember, and my driveshaft is the un-altered factory version. I'm using my factory column shifter, although I had to bend it a little for clearance. I'm also using a long water pump setup and a 3-row copper and brass radiator mounted in the stock location. I have 2 Hayden Tornado fans pushing from the front and they're wired up in two stages. It seemed to me everything fit in very easily. Also very easy to work on. I will suggest using a 153 tooth flywheel and the corresponding starter. It tucks in a little closer to the block and gets your starter away from the headers.

[454_72_4X4]

Originally Posted by Myself

and my driveshaft is the un-altered factory version. mounted in the stock location.

That tells me you have room to move the motor back. I cut 1-1/4 in. out of my stock driveshaft.
Not sayin ya have to move it. Just sayin that's what I did. I like the motor as far back as absolutely possible, (+ an inch...LOL)

[Myself]

You can't move it back any further and keep the column shift rod. It starts to put everything in a bind. When I first got it broke in I took off with it in first and it shifted itself into 2nd before I was ready. Well, instead of going into 2nd , when it shifted the motor torqed over and caught the shift rod and threw it into neutral. It was very exciting with my foot to the floor and the lifters floating. I thought for sure I just blew the rear or the trans. Then I figured out what happened and slid the motor a little more forward. In an S10 truck this might be a problem because they have traction issues anyway. But with the extra rear weight in the s-blazer it's not a problem at all.

[454_72_4X4]

Originally Posted by Myself

You can't move it back any further and keep the column shift rod. It starts to put everything in a bind. When I first got it broke in I took off with it in first and it shifted itself into 2nd before I was ready. Well, instead of going into 2nd , when it shifted the motor torqed over and caught the shift rod and threw it into neutral. It was very exciting with my foot to the floor and the lifters floating. I thought for sure I just blew the rear or the trans. Then I figured out what happened and slid the motor a little more forward. In an S10 truck this might be a problem because they have traction issues anyway. But with the extra rear weight in the s-blazer it's not a problem at all.

Ahh yea, the column shift would be a problem! LOL I had a B&M floor shifter in mine.
I have a factory floor shifter for my 98. I think it's cable on the original column shifter too. Been awhile....LOL