Webmouth247

iTrader: (1)

ok i read through this thread and the other how to t56 thread and maybe i missed it but the answers im looking for seem to get loopped around.
Lets start with this. My car is a 89iroc 5.7 tpi auto
Q1. My speedo, is it worth getting the abbot box or better to get an autometer? and where do i get a abbot box at?
does the autometer fit in my stock guage housing? and do i need a sgi-5? i dont care about cruise....
Q2. Do i need to change my ECM or get a chip? if so.. which?
Just to verify.... which starter do i use???
I think i got everything else figured out i just dont quite get the wiring part yet but i guess that will come when i get started on the swap.

thirdgenrs

iTrader: (1)

LT1 Starter with a T56, I havent had a working speedo in 3 years. GPS FTW.

TKOPerformance

I've yet to read a post from anyone who uses an Abbot box. I looked at the option when I did my swap, and for $350 at the time it was not cost effective. I decided to run an Autometer speedo and a Dakota Digital SGI 5 instead. The SGI 5 sends a corrected VSS signal to my ECM and cruise module. Even with a mechanical speedo you still have a VSS in a 3rd gen if you have EFI.

The Autometer speedo does not fit in the stock cluster; you didn't really think it was going to be that easy did you? I built a new cluster to house mine and swapped all the gauages for Autometers at the same time.

Do you need to change the PROM? Maybe, maybe not. The car will run fine without a change, but you may get trans related SES codes. If you do a chip for a 5 speed car or a custom chip will solve the problem.

You don't need to use an LT1 starter, which tends to be expensive. You can use any small block starter for a 153 tooth flywheel. If the bolt holes are straght across it's for a 153 tooth flywheel. Stagged bolt holes are for a 168 tooth flywheel.

Webmouth247

iTrader: (1)

Thanks TKO....
So what did your cluster run? Do you have pics of it in the car? I don't know if this is covered but what about switching to 91 speedo of cluster? Is that an option?

TKOPerformance

My new cluster cost about $500 by the time I was done. It is completely custom fabricated. PM me your email and I'll send you some pics. It looks awesome, but I am partial of course.

tom86iroc

iTrader: (1)

i use the cable x box wasn't that hard of an install at all i just needed a cable made up with the right ends and length since i put it under my pass seat works perfectly no problems and its been in for like 5 years now and it's easy to configure and wire up

(GYTR)-YAMI_SR

where would you guys say would be the cheapest place to get the speedo conversion box? And i assume it will be easier with the motor out to to the master cylinder and pedals?

TKOPerformance

Not sure on the speedo box. The two places that offer them of which I'm aware are Abbot and JTR. Keep in mind that's dated information.

It makes no difference with the motor in or out doing the master and pedals. I didn't have mine out when I did my swap and it went smooth as could be. One thing I will advise is to pull the master cylinder bracket, associated hardware, and the pushrod mounting hardware from a T5 3rd gen in a wrecking yard. Using those parts it's an easy bolt in and it looks factory. The only thing you have to do then is cut the hole, and the firewall pad should be cut for it already. Use that as a template and cut from the inside. It's very straightforward.

alloy

iTrader: (16)

JTR doesn't do the speedo mods anymore. Hasn't for a long time. I believe I'm the only one that does them now.

https://www.thirdgen.org/forums/clas...xcellence.html

88 TA GTA

Hi Everyone,

Belated Merry Christmas and Happy Holidays to everyone!

I wanted to say thank you to all that have helped here. Greatly appreciated.

I have a question about the bell housing cover or shield. No one has discussed this part. I bought a complete set from a 4th gen w/ pedals master/slave cylinder, bell housing, but it didn't come with a shield. I have read where some bought from Mcleod for 400 to 700 dollars. In other threads they mention NHRA rated scatter blanket/s. Is this part necessary for 320 to 350 HP?

Additional Pedal info: Mine didn't come with the wiring connectors, I pulled mine from a yard and even the front wheel drive sticks use the same wiring. Found mine in a 2000 Pontiac Sunbird GT I wasn't sure these would fit but they are identical.

Does anyone know what the pin switch (white) at the top of clutch pedal is for? (small two wire connector) It touches when the pedal is at rest (not pressed), I do not believe this needs to be connected to a 3rd gen, correct?

Thirdgen89GTA

iTrader: (5)

I know very few people who run a shield under 400rwhp. That is not to say that something catastrophic can't happen, but its an expense that usually doesn't get added till later. I'm not running one on my swap and its expected to go a little bit past 420whp(if I'm super lucky and hopeful)

88 TA GTA

Thanks for such a quick response! Good luck on the 420WHP!

My 355 is mild, I was talking 350 HP at the flywheel not whp, so I'm sure I'm fine with a SPEC stage 1 and SC66S (for the 2 pc RMS) Would it offer any protection from the rear seal leaking ( I don't believe it would, but I have seen a few suggesting to replace the RMS w/install as it can damage clutch etc. if it starts to leak. My block was rebuilt very recently less than 5K miles so I was just curious.

Hey it took a couple hours to read through this thread so I made a short step by step version strictly from all that is listed here. I noticed the thread got chopped so I fixed that in the short version. Let me know if anyone wants it or where to post it.

Cheers and thanks again to everyone.

88 TA GTA

Hey Everyone I'm having a starter issue. I thought that with the 2 pc RMS block you could use the smaller gear after market racing starter?
My Spec flywheel was designed to be just as the original flywheel so shouldn't it bolt up and engage properly? It looks to be an inch out with the one set of holes and it touches it with the other.
Any assistance would be greatly appreciated.

88 TA GTA

To answer the question above - yes it does bolt right up. Had to cut out a small corner on the starter block due to headers, but with that and adjusting rotation it works fine on the 153 tooth Spec SC 66S flywheel (custom for the 2 pc RMS), it was previously on the 168 tooth auto flywheel.

TKOPerformance

I am not familiar with every single combination over the course of the small block Chevy's production, but as a general rule there were two flywheel/flexplate sizes: 153 tooth and 168 tooth. Each uses its own starter. The starters have different bolt patterns, the 153 tooth version is straight, while the 168 tooth version is staggered. As far as bolting up to the block this isn't typically an issue because all but the very earliest engines are drilled and tapped for both starters because the factory didn't know which block was going in which car. Since the T56 setup uses a 153 tooth flywheel (a 168 won't fit inside the bellhousing; I tried one just to see) it needs the corresponding starter. I've heard of guys using the LT1 starter, but they are pricey, much like the aftermarket gear reduction units. I simply went to my local NAPA and bought a starter for a car my same year with a stick, which was less than $100 with a warranty. If it ever fails a replacement is cheap and available at a dozen stores. I had no header clearance issues either (Edelbrock T.E.S. headers). Long tubes are notorious for clearance issues though, so if you have them you may need to do some finagling.

As for the bellhousing vs. scattersheild debate I'd say leave it stock. Unless you are racing and it's required a scattersheild is really nothing but a waste of money and a P.I.T.A. The racing sanctioning bodies aren't taking any chances, and they don't require a scattersheild until you are running 11.99 or quicker, per NHRA. On a street car it's less of an issue, even with big power because the tires are the fuse. The tires will lose traction long before you shock load anything enough to cause a catastrophic failure like an exploding flywheel or clutch.

88 TA GTA

Thanks TKO

That's good to know, I am not so concerned about the scattersheild now.

I really wanted to use the mini starter because stock replacements would suffer from heat soak after a year, I replaced a few and each time it would be fine for a year and then after a 35 min drive, wouldn't start until she sat for at least an hour.I even tried a Ford solenoid on the fender which did help, but I installed it after last stock starter started giving up. This issue vanished w/ mini starter and it under $100 on ebay w/ 5 year warranty.

TKOPerformance

That's a good deal for a mini starter. When they first hit the market you were lucky to find one under $250. Chevy's with headers always have starter problems. The Ford solenoid helps, but doesn't eliminate the issue if the actual starter heat soaks. I have found over the years that reflective fiberglass backed blankets, aluminum heat shields, and ceramic coated headers all also solve the issue. 1 gauge battery cables and a big battery also help. I run an Optima in almost everything and they are usually 700-800 cca I believe. The only downside is the weight, but if placed in the well in the hatch area it can actually work for you to help with traction. That's where mine is. Then the big cable is even more necessary, because the length is much greater.

88 TA GTA

So its in, but believe one of the wires or maybe a fuse link?
My power mirrors, interior lights, headlights, parking lights, heater, (can't select anything - only fan comes on), radio, and digital odometer and Miles / KM selector doesn't work. The system check tells me that all is OK, the beeps and tells me trunk is open, a few seconds and then trunk open again.
I'm going to check fuse links first.....any ideas would be helpful, thanks in advance.

88 TA GTA

Haven't seem much talk about the t56 inspection cover. Is everyone running without it?
Can't seem to find this part anywhere

88 TA GTA

Found out some info.....
There is a "Headlight Door module" located beside the wiper motor, on the driver side firewall. (to the right if you at front of car looking to the back) This controls all items listed above not working. Now mine started working on its own, then shut off and started working again while looking for info on the net. There are fuse links "D" "E" and "G" in the wiring harness under the master cylinder. Haven't had issue since she fixed herself, but will keep you posted.

TKOPerformance

The clutch inspection cover is GM part number 10241153. Mine came with the trans from the wrecking yard, but for some reason I know what that number is. It may be NLA (no longer available) too, but they can usually be fabricated from some sheet steel pretty easily. I had to do that on my old Nova because I had some mystery bellhousing that none of the stock inspection covers would fit. I made a cardboard template for the size and bolt hole locations and just traced it out on some 16 or 18 gauge sheet stock and cut it out. Once it was painted Chevy orange no one would have been able to tell you it wasn't a stock piece.

87350IROC

iTrader: (2)

Another option for the inspection cover.

http://www.f2bkit.com/dust_cover.html

88 TA GTA

I contacted them and they said I should use a T5 cover and modify it. They didn't think there cover would fit the 2 PC RMS block. I don't see how the block has any affect on cover, but followed their advice and didn't purchase it.

91phoenix

iTrader: (5)

I could be wrong but I am assuming that with the 2pc rr main seal the cover might have hit on the bigger end of that crank as compared to the 1 pc rr main. I would also think you could have just cut it a little bigger to accomodate that and have it work perfectly. You have to give them some credit for saying they did not think it would work.

88 TA GTA

Yes, they took the time to look into and got back to me in 4 or 5 days.....

nickdiesel

Good thread thanks for your time.

manolis1969

Here is a detailed video on how to wire a t56 to a dakota digital box...

tonys91rs

iTrader: (17)

I just completed a t56 conversion on my 91 that was a t5. when running all seems well. when I let off the clutch pedal it does not engage until almost all the way out. it feels weak as well. I don't hear any noises but the clutch begins to smoke and smell like its burnt. any suggestions?

tealman92

Did you used the stock t5 peddles and slave assembly?

tonys91rs

iTrader: (17)

Stock peddles and a t56 slave assembly. The clutch feels fine.

BOTTLEDZ28

iTrader: (9)

Did you use a new clutch?

tonys91rs

iTrader: (17)

No I used the set up that came with it. I've got another one coming. In another post it was suggested to put spacers in the slave and back it off

tonys91rs

iTrader: (17)

I'm going t5 to t56. How do I connect to the connections on the trans from the t5 harness.? I guess the cags can be deleted.
Also I may have disconnected my brKe light switch. When I depress the brake pedal there are no brake lights..

tonys91rs

iTrader: (17)

I've got it all out done and resolved a few issues. Last but not least I have these two questioans
1. I went from t5 tot56 in my 91. What do I need to splice or plug in from the t5 harness to the t56 in reference to the reverse lock out and reverse lights? I read cags does not need to be plugged in. I bought the correct t56 connectors
2. For vss I'm going to get a dakotas digital box. Is there a specific sgi-5 I need to get? I see 5 c and 5 e.

BOTTLEDZ28

iTrader: (9)

Its been a while since I did this swap on my last car (2001) but Im pretty sure the only connectors I had to mess with were the VSS signal. I used the SGI-5 box. It was the only one out at the time. The T56 reverse light and brake light connectors were just spliced into the 3rd gen harness and then plugged in. I left the CAGS alone. Leaving it alone will make it hard to go into reverse but you will get used to it.
There a plenty of write ups on here that show you how to make the connections AND how to wire up a switch to the CAGS solenoid in the trans, if you want to utilize it.

jmd

iTrader: (4)

The T5 reverse light wiring should work without change. Or, a pigtail / conn. she'll change at worst.

The SGI-5 has revisions; the newer ones (e) have push button changes which makes them easier to set up than an early SGI-5c with dip switches.

Reverse lockout is simple in that it requires - and + to activate it so pretty much any circuit can be used. There is no ECM circuit to activate it unless perhaps you tune and use the TCC circuit. So, figure out a button or switch. The brake light circuit is bad because it is used at speeds when you do NOT want the reverse gate to be open.

tonys91rs

iTrader: (17)

Ordered a sgi e box. Have that wired up soon. Just need to connect the reverse light. I can do without reverse lockout Is the reverse lights in the upper connector of the t5 trans harness?