Cascade Crew

[scott in wa.]

Help....

I want to get a few good points of view on what the heck I should do on this wiring harness. Iam about two or three weeks away, motor and traini are in with no intake on yet.
It’s on the 88 Iroc vert, (TBI) putting on stealth ram, some what built motor, lt4 hot cam. This is out of the 87 z28 that was wrecked (165 computer)

Should I switch to S/D or stick with MAF ??

I had one heck of a time finding a chip that worked for the 87z28, then buying all the stuff to program with and alot of help form you guys came up with a chip that worked ok.
It’s a fairly big cam, 1.5 roller rockers .495/495 gross lift; you can here it, big time.

Iam worried that the S/D will have a harder time with that cam and I will not be able to get the chip and programming down. If I do go speed density can some one throw me a bone, (or the whole steak????)
Is speed density the way we should go?????
Hell, Iam having trouble finding a 1988 Maf harness anyway and the S/D’S are a lot more plentiful right now.


Thanks
scott

[scott in wa.]

So come on guys,
Anyone got any info ??
thanks
scott

[Twilightoptics]

Tuning will be more difficult and easier at the same time. Just a new learning curve is all.

You can use the same 256 chip... I believe you program it just once.. no stacking.

The adapter you have should be the same.

I like SD for a few reasons:
A: I hate maf (atleast ours they are inaccurate and restrict flow)
B: Making your intake looks and IS much cleaner/easier because the maf isn't in the way
C: SD is more like a carb, so It's easier for me.
D: Yeah I have others I just can't think of them.


Instead of the MAF sensor, you have all other sensors plus the MAP. So it's not a big wiring change, and you need to plumb the map to manifold pressure. I have mine coming off the back of the plenum.

[scott in wa.]

will the cam make it a huge problem? lt4 hot cam.

If I can't use the 165 harness for the speed density, what do I need? ecm number and harness year (speed density )?
will this harness plug into the drivers side fire wall like the original?
will the harness and stuff be plg and play.???
The speedo is set up different right?
thanks
scott

[scott in wa.]

re did last post

S/D
I have got to Buy a Harness and computer tomorrow, to be put in this weekend.

What year of a harness and what computer do I need? If I do buy both together, it should be pretty much plug and play correct? Except for the speedo.

Took the new stealth intake for powder coating yesterday, will post some pics when it gets back.

Got the new K member in and the front end back on, the wheel base is 101 inches from center to center on the wheels, it ise to be 1.5 off on the passenger side. It was a real pain putting in those springs. All new a-arm bushings as well. Engine and trani are in with no intake yet.
BUT now the car sits way high it sat very low before. same springs as well.
will the front of car settle??? crap maybe I did something wrong in the front end?
Well I tightened up everything when it was off the ground, so I will loosen it all up on level ground and see if that makes a difference, I bet it does.


any ideas on the front end as well???

Yep I think Iam DUMB A$$

I read the high dolor manuals and thought I did what it said, but Hey I could be dyslectic, I found this statement on the web for the third gens.

"Are the springs installed upside down?

The tops should be flat and the bottom should have a 1/2 coil left that feed into the slot on the a arm."

(Shoot I wonder if my manual has a typoo, (I dought it)

I will have to pull them again...
LOL..
And I was just telling my kid I love to help him work on his car....



thanks
Scott

[Dewey316]

I would go speed density if it were me, there is actualy a lot of info on TGo about switching from TBI to speed density TPI, you can basicly use yoru TBI harness, and just repin, and use the right computer.

[scott in wa.]

I will have to buy another harness, the old TBI was sold as a complete running package, motor tranni computer and harness. ($300.00 not bad)

So,
I have been searching TGO alot, But I like to beat a dead horse.

1.
what do you recomend as far as year, for the harness? 1991?
I have found one of these for $100.00 at the wrecking yard.

2. Will you guys give me a hand on the prom stuff again?

thanks
scott

[Dewey316]

91-92 are the only years for SD, they should be basicly the exact same thing.

We will try to help you as much as we can. As you saw last time, for 300 miles away, on the internet, we can only be of so much help.

[scott in wa.]

On the S/D
How are you getting around the cam issue? (lt4 hot cam .495/495)
Aren’t you having some kind of idling issues?
What did you change on the prom?
Does it matter on the year as far as S/D computer and harness, are they all the same numbers as far as computer goes?


thanks
scott

[Dewey316]

they should all be the same.

You are tuning the VE tables. SD works by calculating the injectors pulse width, based on calculated load, via the MAP sensor, and the RPM of the engine.

[scott in wa.]

I looks like there are a couple ECM's to consider.

also on the cam problem, maybe its not the lift but the lobe center at .050
that are the problem area at idle.


@0.050 cam lift 210° 228°


Is any one running somthing like this or bigger with s/d??

scott

[Dewey316]

I'm runing 206/216 on my 305, Paul is running a much bigger cam on his 355. You'll be fine wiht that cam, you will just need to tune it a little.

--John

[scott in wa.]

So You guys are running the S/D harness?

I have been searching allot about doing that swap,
The problem is I don't have the original TBI harness or Id just do a re-pin.

So My other option is to go buy a used 91/92 S/D harness and computer.
I don't see anything on the web for doing exactly what I want to do, just some bits and pieces. (88tbi to a 91/92 S/D)


Iam just wondering If that newer harness will wrap around and plug into that firewall on the drivers side.
And how much work it would be to get the ADL working, so I can do some data logging.
What are the problem areas of doing this stuff?


Ps, Yep my front springs are in up side down…..LOL…

Thanks
Scott

[Dewey316]

Scott,

My car is TBI, from the factory TBI cars are a SD computer. Paul is running an aftermarket computer, that uses a SD system. So although we haven't done what you are doing, our cars are both speed density.

IIRC, CheezeX is running a SD system on his car also, and is running a 450hp 406TPI setup.

I am not sure if anyone here has swaped from TBI to the factory TPI computer, so you are probably on your own for some of that. YOu should be able to to get the ALDL stuff going, you just need to get the data pin connected to the comptuer correctly.

[Twilightoptics]

I can't say it enough....


C950 baby. Reuse your sensors... gives you real time tuning with harness and ecu! AND WB capability.

Wish I would have saved up and gotten that before trying all the other gm crap and having the maf die. lol

[scott in wa.]

Ya, I have been looking at those as well.
But Crap they are big bucks, like close to $1,000.
What’s the lowest price you have seen this system for?
Where at?

I see one on e-bay that doesn't work, he said Holley, doesn't not have a repair service for these units. So Iam thinking that if one does go out Your SOL. Do you know anything about that??

Id like to but big money.

Found a harness last night at the yard, 91 iroc tpi, 7730 ecm, said sure go take it out, 75.00, was starting to pull it when they stopped me, said they had to make sure the motor ran before we yanked the harness. Its a nice one but its stock, with a Napa 7730 computer, that’s an extra 60.00



Been talking with this guy on a new harness, sounds interesting, not this one, but specific for my car.
check it out, Iam trying to find out if they have a web page.
http://cgi.ebay.com/ebaymotors/TPI-Speed-Density-700R4-trns-fuel-injection-wiring_W0QQcmdZViewItemQQcategoryZ33553QQihZ003QQitemZ130016716804QQrdZ1QQsspagenameZWDVW

Scott

[Schultzy89GTA]

Commander 950 for TPI $865.99 at Scoggin-Dickey.

http://www.sdpc2000.com/catalog/4326/products/11838/1985-92-GM-TPI-Commander-950-Engine-management-Systems.htm

It is $940.69 at Summit Racing.

-Schultzy

[scott in wa.]

Ya that is better.
But Still Ouch.

Id go maybe $600.00

Oh, Here is another one that would work I believe. for our car.
http://cgi.ebay.com/ebaymotors/TPI-Speed-Density-700R4-trns-fuel-injection-package_W0QQitemZ130018021440QQihZ003QQcategoryZ33553QQssPageNameZWDVWQQrdZ1QQcmdZViewItem
what do you guys think??
scott

[Twilightoptics]

[aaron_sK]

BTW, what the hell is this?