I'd say it's a matter of preference/budget/what deals you find. I opted to swap in a 4th gen rear with 3.23 and posi into the back of mine. Got me posi, decent ratio, good disks... all in good condition... for $100 - complete from caliper to caliper. It was really hard to beat that. The posi is a bit weak with the 275's I have on there right now and will only engage properly about 60% of the time. No problems at all though before the tires warm up or when I was running 245's.

Search on here and you'll find all the info about doing the actual swap. There's even a guy who makes conversion cables for the e-brake, but I made mine work 100% with using the stock 4th gen cables. No welding... nothing.

Gears, posi, disks, etc... will def. set you back more than $100... so it's all kind of a matter of what deals you find and how sure you are that the piece you're getting is in good shape. I think that $100 was pretty well spent for me. Held me over till I can get a much stouter rear back there.

Your tires will rub running 3rd gen wheels with a 4th gen axle unless you've got decent travel on a fresh suspension.

Good luck

 

Pros to the fourth gen rear is that theyre easy to come by and are newer, more likely to be in better condition, and usually have a good ratio 3.23 3.42. The cons to them would be that you will need custom e-brake cables. I couldnt find any that fit except for Eb Miller's. And the personal preference part is that they make stock wheels stick out more. They sit at about perfectly flush with the lip. I cant decide if I like it or not, you should mock your wheels up and see how you like it before you buy one

 

I modified the 4th gen balancer bracket for the e-brake cables so i can run factory 4th gen e-brake cables at a fraction of the cost of the 3rd gen kit, and the balancer is fully functional and adjustable and everything. 4th gen axles aren't bad, but to confirm, without my air shocks my 245s on '88 formula wheels do rub. I got a set of 91/92 camaro wheels with 235s on them i'm going to try and see if they are any better with being a little less wide.

 

guess ill keep my eye out for one and if i get a good price then ill grab it and look for some vette wheels later on.

today i pulled what i think is the speedo cable from the tail of the transmission and drained more fluid, and removed the bolt through the trans. mount. just gotta get the shifter off and then put the car back on the ground.

 

I'll confirm this once more since there's always conflicting info about this - you can use ALL 3rd gen e-brake balancer components with 4th gen e-brake cables. I've done it. Just running all from memory, I re-routed the way the cables ran around the axle, ran the cable guides through the portion that the 3rd gen guides would usually clip to (3rd gen has longer exposed cable length). There was then a bracket in the tunnel that i fastened the end of the 4th gen guides to with some clamps. It's worked perfectly for me for 6 months.

If I wasn't so busy, I'd do a quick tech writeup for this. There's always conflicting info and tons of people say you need to use a 4th gen balancer or conversion cables, but I've been running without either for months... using the e brake every day... working 100%.

 

alright so besides watching the classifieds now for a rear end, i was reading up on the fuel level sender problem for my plastic ls1 tank since it feeds a 40-250 ohm range empty to full, and thirdgen gauges read 0-90. a new sender for the proper range is 100 bucks, and i dont feel like doing the radio shack mod, so heres what im planning on doing-

i am going to leave the tank sealed up like it is now with the regulator removed but the stock sender, wire it in, and then up under the dash mount an Arduino microcontroller (about 30 dollars, i have a bunch from robotics) with its own 12v power that will scale the ls1 sender to 0-90. This should give me an accurate reading and save me a good chunk of change. If i get a simple schematic and code for the controller i will post it up in case somebody else feels inclined. I was also considering running sequential turn signals and other stuff through the arduino, but thats all extra once im done.

 

started removing the interior, pushed the shift cable and grommet through so the transmission is ready to come out. i started chaining up the motor and tranny, so the pull will happen by the end of the week.



in other news, pocket has convinced me not to use the plastic ls1 tank- instead its for sale in the classifieds: i am taking the pump out and installing it into a thirdgen sender and retaining my stock tank to make less work for myself in modifications and fuel lines.

 

did some miscellaneous stuff today - pulled the cruise control wiring out entirely, disconnected the rest of the stuff from the auto shifter except this one cable that i dont recognize- there was one to the trans. through the tunnel, then the wiring clip, then this:

what is it? it disappears into the depths of my console.

i also cleaned up my blower motor and resistor pack so i can get my firewall cleaned up after paint (which i am now doing black after the motor is out)

also removed the ls1 fuel pump from the plastic tank for re-use.

 

Looking good

The cable goes to the column. It prevents you from pulling it out of park unless the key is on

That blower box is flippin sweet

Pulling the pump wasnt so bad was it?

 

no it was easy- i had already had the sender apart before, im always just nervous with the unknown- this is an expensive hobby :P i just snipped the two fuel lines off the pump and left the electrical unplugged, im assuming that will be ok. I also pulled it out of the rubber sleeve and left that in.

can i remove that cable entirely from the shifter and column?

also im going to have to cut the nipple for the condensation hose/vent tube and screw it in to the new box as well.

 

You wont need it for your T56, so yes

Drop the column and pull the switch off. Id suggest putting a shred of cloth under the rod with a piece of tape to keep it from rattling

 

ok perfect.

tomorrow im planning on taking the motor out- everything should be free and i started chaining it up. if it doesnt come out by the end of the day im going to be really disappointed. its going to take a few days of my lab time to clean up the bay and then paint, so i want to get going as soon as i can, plus i have to install the front end steering rebuild kit i have. (my big question there is adjusting everything properly, like the tie rod adjusters, how do i know where to adjust them to haha, and also installing ball joints...?)

anyhow, everything still seems to be in order. i bought paint tonight for the bay, im going to spray the blower motor before i screw it down to the box to clean it up.

 

Ball joints are pressed in, borrow the tool from advance auto

You cannot adjust the steering components correctly without an alignment machine. Eyeball it semi strait and drive it directly to a tire shop for a front end alignment

 

well today was interesting...

during my lab time i chained up the motor under the bellhousing, then to a lift point on the front of the intake. Everything was disconnected and ready to go, but when tension was put on the chains the whole car came up with it. After a whole lot of shinnanigans with the transmission and a TON of lost fluid on the ground (i know, you guys warned me), it finally started to slip out. It pinched against the exhaust and got stuck on the oil filter, but overall the pull took about 15 minutes once we got it moving. Now on to pics:


my teacher helping me out


me being silly



the old drivetrain


the bay now!

my fuel line stuff also arrived from Jegs today, minus a few fittings that are on backorder.

 

looking good man! I'm about to do the same, except the tranny. Its staying in. Can you do me a favor and tell me how many bolts are on the bell housing? Connected to the tranny? I plan to disconnect the tranny from the engine and then slipping it out. I think now that the engine is out, you should get a sponge and bucket and clean around in there...maybe rattle can some of it...keep us updated!

 

Congrats on the swap, I have been there and it is going to get to be stress full

 

there are 6 bolts from bellhousing to engine block plus the 4 little screws for the torque converter dust cover and 3 converter to flexplate bolts

 

thanks

 

so i got a few rattle cans of black engine bay paint in today, still waiting on two back-ordered fuel rail adapters from jegs for the fuel lines. In the meantime i am going to clean out the bay and start my paint prep, as well as install my spohn front end steering kit.

a friend mentioned using aircraft paint remover instead of sanding the bay, then priming the bare metal, then painting- sounds easier than sanding to me. any reason not to?

~Steven

 

no if it will strip it all off then go for it...where did you get your AC delete box for the firewall? it looks aftermarket and im jealous lol

 

HCR13 i believe the auto trans bell housing has 6 bolts holding it to the motor...2 at the top being the hardest.

 

the heater box is from acdelete.com

it was pricey, but i got it as a birthday present. it is really a nice piece, but you have to drill/cut mounting holes for whatever you need yourself. It is dimpled for the stock screw locations, but if you want your resistor pack etc. and the condensation vent...

 

yeah it really is..i have the stock AC delet box but i may go with that one for a cleaner look

 

started wiping everything down today, and got the exhaust un clipped and ready to be sawzalled to pieces. I am simple greening the layers of grime out of the bay before i start stripping the paint, maybe not necessary, but makes the process smoother in the end.

i cleaned up my lake of transmission fluid, and cut that cable off of my auto shifter on the column near where it terminates.

I also stopped by autozone and got a ball joint seperator as well as a Haynes manual (finally).

 

actually after reading the paint instructions again- i am not going to strip the entire bay, its too much of a hassle to roll the car outside multiple times. instead im planning on cleaning the whole area thoroughly, then sanding rough areas and priming over rust- then spraying the actual paint over the existing finish.

i loaded up my car with tape, plastic bags, aluminum foil, and newspapers to mask everything off well.

any objections to that process for paint?


final question for the day- what do i do with the cable going into the firewall that was in the tail of the transmission (speedo i believe)? how do i remove it / do i have to pull the cluster yet?

 

I have a few questions regarding motor mounts:


this is how the old ones are currently- are they supposed to be centered on the k member or is that proper?


one of my new motor mounts looks like this... why?




and this is just me scrubbing the bay down more and more- hopefully it will be painted by next weekend.

 

That looks like a 4th gen motor mount. Use your third gen motor mounts. The old mount on the k-member looks like it is in the right spot.

 

Front mount is for the SBC

Youll see 3 holes behind it for the V6 mount

Your new mount isnt correct. Grab the uber common SBC 3rd gen mounts

 

and so the wiring begins...
i have the whole ecm side of the old harness chopped up- now I need to sort out my c100 wires and get a fuseblock. Then on to the lt1 harness.

 

pulled this out from under the drivers side battery tray..?



continued my engine bay prep



and got some paint on the blower motor so its at least all one color

 

The sphere under the battery tray is the vacuum reservoir for the HVAC.

 

vacuum reservoir goes into the glorious trash can.

progress from this evening:


c100 done...

 

dropped the y pipe and most of the exhaust today, also got the wiper motor out and moved the sbc clamshell motor mounts onto the lt1. did a bit more taping- the bay is a few hours of work away from paint.




any advice on getting that surface rust off the k member before i prime it up? right now im just going to town on it with a wire brush.

 

Wire wheel on a drill. Safety glasses are a must

 

cant believe i didnt think of that- ill take one in to school tomorrow.



here's my evenings work- just need to dremel out a hole for the resistor pack and get some black sealant between everything.

 

Gosh that heater box is sexy

 

what is the heater box from? S-10? I think I'm going to do the same

 

you must have missed it.

 

thats right!
I guess I didn't go back and re-read. Sorry about that...

 

yeah i was really scared drilling into it and while i was threading the screws every time i heard the slightest crack i widened it up a tad. i got some black silicon here tonight so im going to go down now and seal it up and add the resistor pack in.

i also got my fuel sender, 4th gen coolant/wiper reservoirs, and a power dist. block today from Jon

 

got the resistors in and everything sealed up- its ready to install.

now back to wiring...

 

spent all morning with a grinder- took the k member and other problem areas down to bare metal. I also finished masking things off so Monday i am laying down primer.

 

damn good work, hope to be able to swap an LT1 into my car by summer/end of summer,

but those pics of the old engine + trans in the middle of the class room, if i walked into my old tech school and saw a thirdgen getting an LT1 swap IN my class room, i would **** my pants right there and want to do mine with you hahahaha

 

thanks for the compliments.

tonight after swimming districts which took forever...



started on the lt1 harness



my fingers are killing me from fighting with the tape and looming, but whatever. Ill really get into it tomorrow hopefully.

 

Good progress, its not so bad is it? Just time consuming

Your fingers will love splicing 12-16ga wiring

 

ok so i almost got the whole lt1 harness apart tonight- here are my issues:

i could not find labeling info for the 4 t56 connectors- which is which in this picture?
i know im throwing out CAGS...



heres the rest of my spoils




right now i have three entanglements left- coil/icm/grounds, and two strings of four injectors each with pcm pins.

i really dont know what to do with those, and i untaped the injectors which i really shouldnt have done so i have a bit of a mess to deal with...

 

For the T56, connectors the top two are the same connector, but one wire is pink and the other is light green or gray

Light green is reverse lockout
Gray is CAGS

Bottom left is backup lamps
Bottom right VSS

94-95 cars disable CAGS by simply unplugging it. It will still store a code. Since you're knee deep in wiring, you might as well fix it now the right way. Go to radio shack and buy a 2200ohm 1/4W resistor. A pack of 5 should set you back 90some cents. run one wire from the PCM to the resistor, the other leg to IGN 12v. Your PCM will think its locking gears out for you while you're rowing away

You've got a fine start to the rebuild. Fbody harnesses have the injectors wired into banks, while Bbody harnesses have them wired in front/rear 4's. Yours is Fbody so you wont have to separate the individual injector connectors

The coil and module wiring is pretty simple. One to the PCM, several IGN hookups, and several grounds

This should help

 

thanks, im pretty comfortable with where im at right now- i just need to make sure i get the commons back in right.

also, i had CAGS removed from the pcm when i got it tuned, so I should be able to toss the connector right?

 

Correct

 

so i dont need to do the resistor fix.

at the lab today i took some of the rust off the sending unit, but had issues with the ls1 pump fitting where the old one was, here are some pictures.



the ls1 pump is slightly larger (not a big deal), but i didnt know the wiring connector is larger.

the big issue though is that the metal thing in this picture wont slide onto the new pump since there is a little plastic nib in the way from the connector


also, the ls1 pump has another line fitting coming out the top, what do i do with that?


also should i go back into the ls1 sender and snip the connector for the pump and put it on there?