TPI conversion 95 GMC truck

[Hardrock]

Hi all.

New to EFI tuning and wanting to learn as much as I can before I dive in.
Right now, we're building a new (to us) shop truck from several parts we have underfoot.

The truck is a 100% stock 1995 GMC 1500.
305 TBI, 4L60e, 3:42 gearing.
It runs well, the stock harness is nice, and it has no codes showing.
It runs the 16197427 PCM.

We're not wanting to deal with the "one year only" '95 4L60e, and the 305 is getting re-purposed into another truck.

Here's what we're dropping in.

A non-electronic 4L60 with a recent (18K mile) HD rebuild from a reputable shop.
Low mile (60K-ish) 350 TBI non-roller shortblock.
Long tube headers and a 2 1/4" true dual exhaust. (no cats)

Right now, cam, heads, induction, and ECM choices are up in the air.

I'm favoring re-pinning to the '730 ECM, and removing the 4L60e trans wiring from the harness.
I believe both the '730 and the '7427 have ESC filters on board the MEMCAL, so no worries about external ESC modules.
(hopefully...)
I know the ESC filter, KS, and cu. in. displacement all have to match.
As I understand it, the '730 also supports on/off (not PWM) converter lockup for the 4L60. Yes?
I will most likely have to incorporate the OEM 4L60 trans wiring/plug into the existing '95 harness. No problem.

I'm not sure if there's any difference in the VSS signal between the '95 4L60e and an earlier ('89) 4L60, or between the '7427 and the '730 ECM?
Optical-vs-magnetic?

As far as cam choice, we've pretty much settled on the old Mellings MTC-1 grind, or the Summit #K1102 equivalent.
(204*/214* @ .050, .421/.444 lift, 112 LCA)
This truck will serve as my wife's back-up vehicle, our shop truck, gopher, daily, winter beater, etc. do-all pickup.
(no towing)
It has to be relatively mild mannered and fairly fuel efficient.

For induction, I'm really wanting to pull an old TPI off the shelf I've had for 20 years collecting dust.
It's an '87 unit off of a 305 Camaro. Just the hardware, no harness, or ECM with it.
It will of course, be ran as a SD setup with the '730 ECM.

Heads with the TPI are pretty much limited to what we have on hand. Stock #193 swirl-port truck, with 64cc.
(unless a nice pair of '083 heads find their way to my front porch....)

Option #2 is a fresh pair of L31 Vortecs that are on the shelf, and either an aftermarket 4 bbl. Vortec intake with single or twin TBI's, or....

May try running a stock Vortec MPFI (not CSFI) in batch-fire mode?? Anyone tried that?

Most likely a pair of .015 steel shims will find their way under whatever heads we go with, and dual electric fans are in the plans. Does the '730 ECM support electric fans? One? Two?

Tuning is going to be handled by either Moates APU1 Autoprom, or Dynamic-efi. Still undecided....

It's going to be a low-budget build, so it's more of a learning experience than anything else.
Most of the cash saved, and experience gathered on this one, will be put to use on my other "toy", later.
('93 Gen V 454 with a vintage SuperRam MPFI)

I know the '95 trucks are kind of an oddball, so any help or suggestions would be greatly appreciated.

TIA.

[dave w]

I'm confused, why use the '7730 when there is an easier and less expensive option to use the '7427 in MPFI mode?

See attached .zip for details.

dave w

[Hardrock]

Hi Dave.
Thanks for the reply.

Basically, I figured swapping to the '730 would give me the option to tune with Dynamic-efi.
I didn't see any support for the '7427 on their site.
Also wanted 4L60 compatibility, and the '7427 used in the '95 trucks is sort of an oddball from what I've gathered.
PWM converter lockup and shift solenoids with one year only Ohm specs.

I didn't know if that was all in the programming, or built into the PCM itself.

Can I run a '7427 with a 4L60? Like a '95 MT program?
How do I handle TCC lockup?

Mike

[dave w]

There are numerous options.
Using the Moates.net Ostrich 2.0 chip emulator ( http://www.moates.net/ostrich-20-the...eed-p-169.html ) with a '7427 is "On Par" with the Dynamic EFI system. Both the Ostrich 2.0 and Dynamic EFI system use TunerPro RT to upload / download a "Tune File".

Possibly installing PWM delete kit ( https://gmtnation.com/forums/threads...from-tcc.7238/ ) into the 95 4L60E is an option, so the '7427 can use a "Tune File" from a 1994 '7427 non-PWM 4L60E.

I've done several '7427 MPFI conversions, it's an AWESOME low cost option!

dave w

[dave w]

Pic of a 16197427 connected to an Ostrich 2.0.

dave w

DSCN4240.jpg

[Hardrock]

Thanks for the link.
I had no idea TransGo offered a PWM eliminator kit. PWM on a clutch apply circuit never made any sense to me. Just more/faster wear.
That would be a nice upgrade to the '96-newer 4L60e's.

I pretty much need to run the 4L60, though.
One, I have it in front of me, and I know the history on it. Two, the '95 4L60e is in a 2WD configuration, and the truck will end up equipped with 4WD when it's done.

Essentially, what we have under our current shop truck is a well maintained 4WD chassis with upgrades we'd like to keep, but the sheetmetal is toast.
The '95 is a cleaner truck, so it's getting a chassis conversion. the 4L60 comes with the chassis, along with a recent Moog front suspension and a 14 bolt SF rear with a locker. Wheels, tires, brakes, etc. Just too fresh and reliable to abandon.

The two combined will make a respectable shop truck, and a TPI should add a little fun to the mix.

Mike