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tbi serpentine belt pulleys work on earlier carburated motor *dual altanators*

I intend to get this exact same setup for my truck. My blazer is an 87 TBI motor. Anyone know if I can reuse my alternator? Also will I have the correct water pump? My water pump is serpentine but not sure if it spins the correct way.
 
i found some where that if you use the full size brackets that you will be able to run a 2nd altantor where the compressor would be. just have to fab up a tab of some sort
 
what about the air pump? theres a belt option to not have an air pump. do i need to run a bypass pully as well?

Some serp set ups didn't come with air pumps. Those brackets wont even except an air pump. If you go back to my picture, there is a small pulley under the AC pulley. That changes locations depending on what other accessories you have.

I intend to get this exact same setup for my truck. My blazer is an 87 TBI motor. Anyone know if I can reuse my alternator? Also will I have the correct water pump? My water pump is serpentine but not sure if it spins the correct way.

If the alternator has the same pulley as the serp set up, yes. Or you can put a different pulley on it. My '85 blazer's alternator would not have worked on the serpentine brackets. The mounting holes are different.

If the water pump pulley is smooth, it spin opposite the crank, which is how the full serpentine belt set ups are.
 
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if you change over to the tbi setups you can also run a 12 si alternator in the air pump location with minor brackets made.

The 'log' style ac compressors or (a-4) were used on the 454 motors, and the 'pancake or (a-6) compressors were used on the 350. I am working on mounting an a-4 on top of the ds valve cover (just like on the 454 motors) but I am attempting to use the rest of my aluminum plate to mount the ps pump. I have already milled my plate to accept a 1/4" plate behind the aluminum plate on the ds to mount the front of the a-4. Then I have the original mounting brackets for the a-4 to mount it on the exhaust manifold and the intake manifold. I ran into a problem, the bolts to the ds manifold are froze up and I didn't want to take a chance and break them before winter hit. Then I can have compressed air and have the ac on at the same time!:D
 
so i can run the alternator i have now in the air pump spot? or is mine the 10 si? would i beable to find a high output powersteering pump to work with hydro assist? and will all this clear my mech. fuel pump? i know ill probly have to reroute my fuel line. i had a 77 with the log style compressor and it worked great for on board air. then it siezed up at the dunes on me. the po made the brackets and installed it. those things weigh a ton!
 
I installed a full serpentine setup on my '86 dually I had awhile back, it will bolt up fine, one bolt will be missing from earlier engine blocks on the passenger side, but I also installed the little bracket arm that connects near the water outlet on the intake and goes over towards the ac side (passenger) bracket area, was rigid enough and worked fine.

I did have to get a new water pump/fan & clutch and a new alternator, then researched which terminals on the alternator triggered the the charging and dash gauge stuff. I also reused the original power steering pump, even with the hydroboost setup, it bolted right into the bracket.

It was set up identical to my '89 Burb. aside from the hydroboost.

I have recently acquired another '87 Burb, and although it looks like a serpentine belt, it's not, it's just a flat ribbed belt system, the water pump still spins the way the older motors did.

I did not run an air pump on the dually, nor does my '89 have an air pump and belt routing works fine.

Mechanical fuel pump will clear the serpentine brackets.
 
Do the TPI style brackets support the A-6 style compressor or will it hit the valve cover?

Did the TBI brackets change between the late 80's and the mid-90's or was is all the same up to Vortec?
 
what about the air pump? theres a belt option to not have an air pump. do i need to run a bypass pully as well?

My '89 Suburban 350 does not have an air pump, no pulley there either, but there is a smaller idler pulley on the bracket between the crank and ac compressor.

I have run a serpentine setup on my '86 dually I had without that smaller idler pulley, belt just ran around the crank right up to the ac compressor, it worked fine, I think it's more of a belt stabilizer pulley, just to keep the belt from flopping too much, it's alittle bit of a stretch between the two pullies.
 
I intend to get this exact same setup for my truck. My blazer is an 87 TBI motor. Anyone know if I can reuse my alternator? Also will I have the correct water pump? My water pump is serpentine but not sure if it spins the correct way.

No, that is a standard rotation water pump. You need a reverse rotation water pump to install a newer serpentine setup.

Martin
 
I have a couple questions and suggestions on this since I am looking at doing the same thing on a 87 tbi that some clown threw a carb on.

First off, instead of worrying about the fan, put an electric fan on and improve your mileage, increase the cooling and open up the engine compartment a little bit.

Second, I understand that if you upgrade to a serp set-up from a later year model, you dont need the air pump. Theory is that you did an engine upgrade and are more efficient thus passing a visual smog inspection without having to worry about air pump smog issues. Just block off the air tubes on the exhaust manifolds. If you can get the 50 state smog legal headers that is an option. Also with the serp mod, you dont need the driver side manifold support for the ac compressor any longer now allowing the change of exhaust manifolds.

Any idea? Am I way off?
 
I have the factory serp set up with my oem ac compressor on the passenger side. I will put the log on the drivers side for oba. But both aluminum brackets are needed for pulley to mount onto for the serp belt
 
I have the factory serp set up with my oem ac compressor on the passenger side. I will put the log on the drivers side for oba. But both aluminum brackets are needed for pulley to mount onto for the serp belt

So you're going to install the A-6 compressor on the drivers side? where the alternator is located, or are you planning on fabbing up some new brackets for it, or the alternator?
 
Same place its at now. The log will be very close to it but lower. I have milled my aluminum bracket to allow me to add a 1/4" bracket behind it and into the heads for the front of the log. For the rear it will mount off of the first 2 or 3 exhaust studs. I will power the log with an auxillary crankshaft pulley (like what spools a supercharger) so I don't have to align the log (or change the clutch over to a serp pulley) with the oem serp setup
 
I found a picture of a Sanden installed on TPI brackets. The guy said he just had to make some spacers and use different length bolts to replace the R-4 with Sanden:

Sanden2.jpg
 
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Just goofin, the factory pancake style compressors on these trucks are R-4 compressors. A-6 are the long log type found on big blocks mainly.
 
Serpentine, Serpentine, /\/\/\/\/\/\/\/\/\/\/\/\/\/\


Sorry, Everytime I see or hear the word, that goes through my head. Back to the conversation.:thumb:
 
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