S10 Hop-Up

[shmonty]

Hello there. I have a 1993 S10 2wd 5spd with a 2.8L TBI. My question is how
or what can I do to get more power out of my engine? I really don't want to
swap engines. I know the basics of cold air, exhaust, ignition upgrades and
pcm chips. I am mechanically inclined so I won't be scared away easily. I greatly appreciate any info I can get.


Thanx

[G-U-NOT]

All that stuff you just mention that you know about... thats pretty much all your looking at with that engine!!
If you want to get more power, you're going to need to port & polished the heads, maybe even have them milled down to bump the compression up a tad.
You can also get a performance cam too!
Your truck probably has 3.42 gears in it... step it up to some 3.73 posi gears or maybe even a steeper set!!
Do all that stuff to your truck, THEN tune the pcm for all the mods!!
I have a 93 s15 Jimmy with a 4.3L Vortec engine in it and Im working on some mods as well and Im going with 4.56 gears because Im putting 31s on it!!... let me know how it goes!!

[ezrollin]

If you want any noticeable gains swap do a 4.3 tbi w/2.8 injs. a 260 cam and free flow exhaust. You will need to bore your intake tb bores and you might check the 272 cam.

[G-U-NOT]

He doesnt wanna do a motor swap, thats the thing...
Besides, the 4.3 TBI is junk!
If you're going to go with a 90* engine, might as well get a 4.3 Vortec with a 700R4 trans!

[Canyonero]

http://www.4x4wire.com/tech/60degreeV6/index.htm

[ezrollin]

He doesnt wanna do a motor swap, thats the thing...
Besides, the 4.3 TBI is junk!
If you're going to go with a 90* engine, might as well get a 4.3 Vortec with a 700R4 trans!

No,you misundestood,I meant to bore the throttle bores on his manifold and install the 4.3 tbi unit with 2.8 injs;it's like putting on a bigger carb,with cam and freeflow it will wake up your 2.8 !

[shmonty]

By the way. I live in California so smog will be an issue. If I use the 4.3 tbi , do I have to change computers or will the 2.8 pcm work fine?

[Canyonero]

The 2.8L ECU will work fine. You'll be keeping the injectors from the 2.8L, the larger throttle bores on the 4.3L throttle body simply allow better air flow.

betterthanyou has a nice write-up on this: http://members.shaw.ca/betterthanyou...3tb/28to43.htm

[jwvess00]

Hi there!

The fastest path to power in a 2.8V6 S-10 is a 3.4V6, either as the crate engine from GM or as a donor engine from a F-body. It is a bolt-in swap.

The 4.3 TBI is a great swap. It makes a noticeable difference. You're looking for a 4.3 TBI that has the throttle cable bracket bolted to the TBI -- the older ones don't, and there isn't enough meat on those to drill/tap the TBI for the 2.8's throttle cable bracket. You'll also have to remove the 4.3's throttle lever (it's platted/spotted on, so this means a die grinder or similar to cut it off of the shaft -- do NOT cut the shaft!) and install one from a 2.8 TBI (or one that matches) on it. and weld it in place (30 seconds or less with a MIG).

If that sounds like too much work, the 2.8V6 Holley TBI has the same throttle bore size and bolts on with not cutting/welding (though boring the intake is recommended). I have one that I don't need and am willing to sell, but it needs an injector cleaning after sitting for two years.

[Canyonero]

If that sounds like too much work, the 2.8V6 Holley TBI has the same throttle bore size and bolts on with not cutting/welding (though boring the intake is recommended).

Doesn't not boring the intake to match the larger throttle bores defeat the purpose of installing a larger throttle body?

Tell me about this Holley you have. I know people who may be interested.

[jwvess00]

Hi there!

Canyonero, boring the intake to match the TBI is done for a couple of reasons;
1) On a stock 2.8 TBI intake, the 4.3's butterflies will hit the intake when you open the throttle. Your choices are to bore the intake or put a spacer under the TBI that has a bore size that matches.

2) Boring the intake lets the intake flow more air to match the additional air from the TBI. The 2.8 needs more air, and a larger TBI combined with the intake machined to match helps. Without machining the intake, the intake becomes a restriction.

[jwvess00]

Hi there!

I bought the Holley 502-3 2.8V6 TBI used several years ago, and ran it without any problems until I took two years to do paint/bodywork (I'm slow. and lots of things jumped ahead in line over those two years). After sitting for two years, one of the injectors stopped spraying. As far as I can tell, it just needs a good cleaning (i.e. LIndertech ) but I haven't gotten around to it. I have the TBI and the injector connectors (Holley used a different connector than GM) but not the adapter plate that allows it to be bolted to an unbored intake. If memory serves, I have tried it on an unbored intake and it does not have the same issues with the butterflies hitting the intake like the 4.3 TBI does. It has the "old" style 3-pin inline TPS connector. I am not using it, and do not plan to use it in the future. If someone is interested in it, ping me.

[Canyonero]

2) Boring the intake lets the intake flow more air to match the additional air from the TBI. The 2.8 needs more air, and a larger TBI combined with the intake machined to match helps. Without machining the intake, the intake becomes a restriction.

Yeah, that's what I was getting at. You don't HAVE to bore your intake to use a larger throttle body, but if your intake is still restricting you will only get partial benefit.

[daytonxx]

so what do i need to do

i have a 1987 2.8 v6 can i get more horse power out of this

[jwvess00]

Hi there!

The easiest upgrade is the 3.4V6 crate engine from GM, or a '93-'95 3.4V6 Camaro long block. It is a bolt-in swap.

Otherwise, all of the standard hotrod methods work -- headers, cam, head work, different rocker arms with a higher ratio, bigger throttle body, machine work to the intake, etc.