fixin up a 91 sonoma

[howley brad]

i have a 91 Sonoma obviously and im wondering if i can use any s10 / s15 part and how to tell if i have the 2.5 6cyl or the 2.8 6cyl


thanks !!

 

[howley brad]

no one can help me ?

 

[Molson02536]

In 1991 you ether have a 2.5 4 cylinder , 2.8 V6 or the 4.3 V6. No once can help you cause we don't know what is a 2.5 V6. On your Vin# the 8th character will be your engine type. 1991 A = 2.5L 4 Cyl E = 2.5L 4 Cyl R = 2.8L V6 Z = 4.3L V6

 

[howley brad]

ya the guy who sold me the truck was a retard its a 2.8 v 6

 

[Molson02536]

i have a 91 Sonoma obviously and im wondering if i can use any s10 / s15 part and how to tell if i have the 2.5 6cyl or the 2.8 6cyl


thanks !!

Suspension:

One of the reasons the S10 truck is so enjoyable is that the suspension can be modified with Bell Tech 2" drop spindles or from a Extreme S10, de-arched rear springs with air shocks (the softest riding air shock for the S-Truck), a 1-1/8" front anti-sway bar from an S-10 Jimmy/Blazer, and a quick-ratio power-steering box (2-3/4 turns lock to lock) from a 1997 S-10 SS or one from the extreme S10.

Engine:

Your best bet for a close to stock looking engine bay with increased power would be the 3.4 SFI. those can be had from newer GM minivans like Montana's and Chevy Venture's. You CAN also change to a 3.1/3.4 and keep it looking 100% stock... the stock intake platinum fits right up to the 3.1/3.4 so when you look at the engine you see the same 2.8 but your really looking at a 3.4!!!!!! :beer:

The problem with getting power out of 2.8, 3.1, or 3.4 60*V6 is the intake. It is unbeleivably restrictive. It simply reaches maximum air flow at around 4000 rpm. Larger bore, stroke, or cam will run you out of air sooner. Many have put the 3.4 rated at 160hp into your S10 with the new intake and run it as a MFI from a Montana or Venture. To get any real power out of the 60*V6 and keep it stock looking you MUST Find a way to modify the inside of a stock manifold and mode out the Throttle body by swapping it out the injectors with a one from a 4.3/5.7, but your going to have to mode the throttle body.

The bores on the 2.8 throttlebody are the first big bottleneck, you would have to grind or hone the bores in the intake manifold. Thats the most complex part of the swap, and you would also need to rework the throttle bracket and cable because the 4.3/5.7 throttlebody mounts it slightly different. Then you would have to switch out the 2 fuel injectors from the 4.3, you can just swap the whole injector pod from your 2.8 TB to the new 4.3 TB.

You can always do a simple custom turbo set up. With a TBI set-up, the best bet is to add auxilary injector(s). Using an FMU will only go so far, though it would be enough for a low boost application on a fairly stock engine. Swapping to larger injectors from a 4.3 or 5.7 might almost be needed, depending on how far you go. Then tuning the bin file on the chip will be needed.

Going MPFI will get a better dispersion of fuel, but is not completly needed.
You can also convert just the intake, while retaining your existing ECM with only mild wiring changes. But again tuning the bin file will be needed.

A turbocharger will NOT increase gas milage, no way no how. The turbo no matter how you look at it, is a restriction in both the intake and exhaust, and because of this fuel comsuption will go up silghtly in off boost situations. A turbo charged engine will usually get better fuel economy over a similar power output naturally aspirated engine, due to the additional fuel only being needed when in boost.

Adding a turbo is that it is used to increase power, to gain more power you need to use more fuel, fuel economy will go down, especially when you get into boost. If just simply adding a turbo to an engine would increase fuel economy, EVERY OEM manufacturer out there would be adding a turbo to every engine they built, to get the total fuel consumption down across the car line, they would probably make it so that it never created positive intake pressure if it were that simple that just simply slapping a turbo to the side of an engine magically made it drink less fuel.

Good luck on your project and sorry if i got carried away.

 

[howley brad]

holy shit man thanks for the post that alot of good info but its not an s10 i have leaf springs from an s10 and they were too short i of them in by puching the brackets closer together but that put a huge hop on the back end of my truck !!! haha any suggestions how to now lower it back down ?