Project V8 S-10

[tardis454]

The Iron Duke in my 91 S-10 is tired, so it's time for a V8.
I want a solid daily driver that will pass emissions.
I'm using a NV3500 & a stock 78' 350.
I have the parts for the project, but I have a few questions.

1) Exhaust:

I hear long tube headers are the way to go on S-10's.
But I've seen people use exhaust manifolds too.
I'd like to use manifolds, a Y-pipe & converter(s).

What manifolds fit an S-10?
Are there any off the shelf Y-pipes that fit?

2) Instrument Cluster/Gauges:

The NV3500 uses a VSS sensor for the speedo.
"As far as I know" the VSS requires the ECM to work.
I want to use the factory speedo/gauge cluster.

Is there a way to make the factory electronic speedo work without an ECM?
If I hook up the NV3500 wiring, & leave the ECM intact will the speedo work?


If anyone has info on this let me know.
Thanks.

[Loren]

Re: V8 S-10 Questions.

I gather you're not going to use an F.I. on it.

Just to throw a thought out there, I know the TPI cars used a speedo "buffer", I wonder if that would let you dis-include the ECM.

[tardis454]

Re: V8 S-10 Questions.

I gather you're not going to use an F.I. on it.

Just to throw a thought out there, I know the TPI cars used a speedo "buffer", I wonder if that would let you dis-include the ECM.

Thanks for the reply Loren,

I'd do an EFI swap, but I don't have the cash, plus the 78 carb'd 350 is free.
Ohio E-Check doesn't look under the hood during the test.
They only check for a converter, probe the tailpipe, & run it on the rollers.

As for the speedo, a friend claims leaving the ECM intact "should" work.
I want to make "sure" it works, or get the parts to make it work.
I read about TPI "buffered DRAC modules", but I don't understand how they work.

I still use the truck to get to work daily so I'm not in a hurry to get the swap done.
I'd like to have all the parts & info beforehand to make the swap go easier.

[CTX-SLPR]

Re: V8 S-10 Questions.

Buick Regal digital dash cars also used a buffer setup and its available as they do go bad from time to time.

[Schtauffer]

Re: V8 S-10 Questions.

Mid-80's Camaro/Firebird manifolds should fit. I'm doubting on the Y-pipe. I know of several V8 S-10's, they always had an exhaust shop take it from the headers back.

http://www.jagsthatrun.com/Pages/Chevrolet_S-10_V-8.html#intro

[tardis454]

Re: V8 S-10 Questions.

The next question I have is about the flywheel.

I have the 4.3L flywheel with an 11 inch clutch from the donor truck.
The V6 & V8 flywheels are different, & the 4.3L has a 1 piece rear main.
I'd like to use an 88-up fullsize Chevy truck flywheel on the 78 motor.

Are the crank flanges on the 1 piece rear main motors different?

If so, do I have to use an adapter to make the late flywheel fit the early motor?

-Or-

Do I have to use an 85-down flywheel?

[fabricatordave]

Re: V8 S-10 Questions.

no adaptor late flywheel wont work bolt pattern different and all one peice flywheels have ballance weight need to use 85 back flywheel

[BangShiftChad]

Re: V8 S-10 Questions.

The VSS works without the ECM. That doesn't mean your speedo will work without the ECM, but the VSS has power going to it, and then a ground and signal wire if I remember correctly. Anyway, when it is wired correctly, you will have a signal coming out of it. If your stock speedo needs a buffer or whatever, I don't know. Aftermarket gauges will take the VSS signal and work fine.

[HoosierGTA]

Re: V8 S-10 Questions.

Mid-80's Camaro/Firebird manifolds should fit. I'm doubting on the Y-pipe. I know of several V8 S-10's, they always had an exhaust shop take it from the headers back.

http://www.jagsthatrun.com/Pages/Chevrolet_S-10_V-8.html#intro

If this is your first S-10 swap I highly recommend buying the JTR s-10 swap manual It is worth the 30 bucks. they also have one for putting a fuelly motor in one. On the tranny I think that if the 91 has an electric ( no cable ) speedo just pug it up and it should work

[Huskinhano]

Re: V8 S-10 Questions.

I bought a 93 Mustang T5 trans for my 66 Mustang a few years ago. The 93 Mustang also used an electronic speedo and the T5 used conventional drive/driven speedo gears to drive the VSS, not a star ring with a proximity sensor. Check your tranny, maybe you'll luck out and just be able to remove the VSS and plug in a conventional speedo cable.

[tardis454]

Re: V8 S-10 Questions.

http://www.jagsthatrun.com/Pages/Chevrolet_S-10_V-8.html#intro
If this is your first S-10 swap I highly recommend buying the JTR s-10 swap manual It is worth the 30 bucks. they also have one for putting a fuelly motor in one. On the tranny I think that if the 91 has an electric ( no cable ) speedo just pug it up and it should work

The JTR books are on the way. My friend claims they don't give much info. I'll find out soon enough.
This isn't my 1st S-10 V8 swap, it's just the 1st S-10 V8 swap that's going to be done right ;)
I helped a friend do a carb'd auto swap in his 82 S-10. It turned out ok, but only half the dash stuff worked.

I bought a 93 Mustang T5 trans for my 66 Mustang a few years ago. The 93 Mustang also used an electronic speedo and the T5 used conventional drive/driven speedo gears to drive the VSS, not a star ring with a proximity sensor. Check your tranny, maybe you'll luck out and just be able to remove the VSS and plug in a conventional speedo cable.

From what I've read the Getrag 290/NV3500 uses a hall effect speed sensor.
I looked for a cable conversion, but found nothing.
Looks like I'm stuck with the VSS


I kinda screwed the pooch on this one though...
I found a good TBI 350 in lieu of the carb'd motor for dirt cheap!
but...
I had a S-10 4.3L 5spd harness handy & butchered it taking the trans out :'(
Now I can't find another harness, go figure! :D
I read that any 88-93 S-10 TBI 4.3L auto/stick engine harness will work.
I also read that 88-93 2.8L harnesses can be used too.

[tardis454]

Re: V8 S-10 Questions.

The last 24 hrs have been pretty enlightening.
I found my long lost Genuine GM Fuel Injection book.



It describes "all" of GM's fuel injection systems in detail.
Now I understand how a VSS sensor works & what the buffer is for.

I can't find a S-10 4.3 5spd harness to save my life.
After a lot of research I figured out a 88-91 Chevy 1500 5spd engine harness should work.
They're basically a lengthened 4.3 harness with a different connector at the firewall.
Hollander says full size trucks used 7165(same as 2.5) & 7747(have one) ECM's.
I figure I can transplant the pins & wires from Chevy truck harness to the S-10 harness socket.

That sounds feasible, right? :P

[fabricatordave]

Re: V8 S-10 Questions.

i have a tbi harness .4.3 stick and auto ecms .harness is out of a g van shortend. and ecms van and c/k truck it was in a toyota with a 4.3 7747 ecms


o yea you can have it just pay shipping!!!!!!!!!!!!!!!!!!!!!!

[HoosierGTA]

Re: V8 S-10 Questions.

I did a 4.3 tbi to a 305 tbi using the 4.3 wiring harness and computer/chip worked pretty good so......I think it should work the other way. ( your way )

[tardis454]

Re: V8 S-10 Questions.

Now that I have a TBI 350 I decided to use a full size Chevy truck harness.
The harness is out of an 88 1500 2WD 350 5spd truck with a 7747 ECM.
There's no cutting or lengthening required so it should work like a charm.

I got the JTR S-10 & TBI/TPI books in the mail today.
They're a bit pricey, but they offer a lot of insight on the swap.
Just a few more parts & I can get started...