SB serpentine swap on the cheap!!!

gmachinz

Frequent Racer
Apr 5, 2005
511
0
0
Iowa
Just in case few people aren't aware of this, I am posting it because we recently tried it out and it was so easy, it should be illegal! We are putting together an '81 Regal and I decided I wanted a serpentine belt design but did not want to go big money on it. I figured after looking at a 4.3 V6 motor that the accessory drive belt brackets should bolt up to a traditional SB Chevy. I pulled the brackets off a 4.3 S-10 Blazer and it basically bolted right up with a few minor mods-very easy! To things were accomplished by doing this. First was being able to swap belts in about 30 seconds and you're done. Next was my desire to keep the AC. And third was to upgrade to a newer style ps pump design. Here's what to do: Yes, you can use TPI or TBI SB brackets but it's easier to find 4.3 versions. Find any serpentine 4.3 brackets up to 1993. You need a pulley puller, a metric socket set (deep) and a long breaker bar to aid in pulling the tensioner back to release the belt. Also, bring a standard and metric flare nut wrench set for the ps lines. Now, you have to use the pulley puller to remove the ps. pulley off so you can gain access to the bolt on the drivers side head that helps bolt the bracket to the head. Once the pulley is off, remove the bolts that go through the ps bracket which extend into the reservoir housing, then move it out and aside and then you can get to the bolt on the head. Above the ps pump is the alternator which comes off very easy-three mounting points here-4 and 7 clocking position bolts and one bracket bolt that is anchored to the exhaust bolts. Keep that bracket because with a few washers acting as spacers, it bolts up to a SB Chevy, too! Use your deep sockets to remove the remaining 3 nuts/bolts and the whole drivers side bracket slips off! On the pass. side, you have another 4 bolts/nuts to remove but this side is easier still. The compressor go ahead and leave it in the bracket once you get all the mounting points off and it all slips off as one big unit as well. Be sure to keep the idlers and tensioner assembly and all pulleys. With everything ready to transfer over to your existing 350 or whatever, you need to pick up a new water pump for your motor but since it's a serpentine now, you need a reverse flow pump. If you have a heater hose fitting in your radiator, use a 4.3 water pump. If not, use a TBI 350 water pump which needs to have the heater hose fitting in the water pump. All pulleys will bolt right up and you will end up using 6 of the 8 total mounting points for the bracket set-the 4.3 block has slightly more mounting locations but 3 on each side will anchor the brackets very well. One more thing, if the bracket set has the provision for a smog pump under the AC compressor, you will need to notch a section out of the lower corner of it if you are using a mechanical fuel pump. That's it-done! The ps hose has the same o-ring fitting if you're g-body is '81 or newer and if you want to retain your AC, grab a set of hoses for a 3.8 car and the hoses bolt right up-there may be slight differences with the bend depending on how the outlets on the drier is located but the hoses can conform to fit just the same. Be sure to grab the pressure switch from the donor car also for use on your AC system. I plan to snag as many 4.3 brackets as I can now from my boneyards. Overall, this can be looked at as an affordable serpentine swap and it works very well! -Jabin
 

Longroof79

MalibuRacing Junkie
May 10, 2004
8,948
9
38
Gainesville, Fla.
Thanks Jabin,
Very informative write up. I plan on going with a serpentine set up myself and appreciate the detailed information...
are you also using the late model A/C compressor, and is the PS pump fittings compatible with late year G-body hose fittings?
Can you also use the crank and water pump pulleys off the 4.3?
Jack :?:
 

ScotSea

Frequent Racer
Sep 21, 2003
381
0
0
These all use that little alternator don't they? The CS130 I think.

I picked up a couple of the larger 120 amp alternators, and would like to use the larger alternator. I was looking in the junkyard yesterday, and all the serpentine setpups I saw all used the little alternator.

Didn't the Camaro TPI's use the larger alternator? Anything else use the larger alternator? The other thing to look out for is if you need room for a throttle body to poke out the front of the engine.

Scot
 

malibujason79

Dragway Regular
Oct 1, 2004
755
0
16
sw ohio
www.cardomain.com
the caprice police cars had a larger alt (amp wise) if you look on the side of a cs style alt is will have amp. rating stamped on it. it is very easy to wire one up, if you need help let me know.
 

ScotSea

Frequent Racer
Sep 21, 2003
381
0
0
malibujason79 said:
the caprice police cars had a larger alt (amp wise) if you look on the side of a cs style alt is will have amp. rating stamped on it. it is very easy to wire one up, if you need help let me know.

I think the cop car setup is the one I am looking for, but I have never seen a cop car in any of the junkyards around here... Oh well.

Thanks, Scot
 

Longroof79

MalibuRacing Junkie
May 10, 2004
8,948
9
38
Gainesville, Fla.
Ribbedroof said:
Quick note: PS hoses went to the o-ring fitting in '80

Good info!
===================================================
So Bryan,
What you're saying is that the late type PS pump would also have the same O-ring type fittings,,correct?
Jack ;)
 

gmachinz

Frequent Racer
Thread starter
Apr 5, 2005
511
0
0
Iowa
Yes, we are using the later model ps pump and AC compressor too. The ps hoses do have the same style of fittings. We retained the stock ps hoses on the Regal and just had to slightly bend the pressure hose to clear the pulley a little better. And correct, you use all of the pulleys from the donor 4.3 motor. It all went together better than expected. The 4.3 motor has two or three long studs w/nuts that serve to help "locate" the brackets on each side but we opted to use bolts. The studs require the us eof an inverted torx socket for removal but we broke the tip off every one we tried to loosen and re-use so we just used bolts for the swap instead-works just the same. One other thing I forgot to mention. Because of the bend required for the upper radiator hose, we used a straight thermostat water neck instead of the usual offset one and used a stock 3.8 V6 Buick upper hose. This allows the hose to come up and over the alternator and it looks a little better, too. -Jabin
 

Longroof79

MalibuRacing Junkie
May 10, 2004
8,948
9
38
Gainesville, Fla.
Thanks again Jabin.
Alot of good information there. I would like to change over to the late type compressor, alternator, and PS pump.
I'll have to see if i can get a package deal on the whole enchilada. I know the U-Pull-It yards will nickel and dime you on every part...
Also, I can't recall...what side does the compressor and alternator mount up?

We do need to make this write up a sticky.
Jack :)
 

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