thenewkid

Ok everybody I need your help again.

I have a 94 z28 with a lt1/4l60e.
Here are the mods as of now:
-52mm Throttle Body
•Hypertech Adjustable Fuel Pressure Regulator
-"Street Ported Heads"
•Crane Energizer 1.6 roller rockers
•MSD 6AL Ignition
•MSD Coil
-MSD Opti
-MSD Wires
•Edelbrock Headers
•Magnaflow Catback; no cat converter
•3.42 rear
•CSR Water Pump
•Hypertech 180 degree thermostat/fans programmed to come on early
•Tuning madtuner.com - Home LT4 Knock Module installed in pcm already
•DMS Motorsports Performance Lowering Springs
•Lakewood Rear Lower Control Arms
•Rear Lower Control Arm Relocation Brackets
•Edelbrock Panhard Bar
•Custom 3000 stall converter, built based on weight of car, rear gear ratio, etc
•CPT Transmission “Race” rebuild, updated “steel piston set for the input drum CPT - Cahall Performance Transmissions: Transmission pricing - 4l60e/700r4
•B&M Transmission Cooler
•Front 1LE Sway Bar
-Corvette wheels

Anyway, I'm trying to budget my LS1 swap and my biggest concern is the transmission. I REALLY would like the keep the 94 4l60e I have now if its possible. Unfortunately, I cant find much info about the 94 version.

Suggestions, questions, and happy thoughts are always welcome.
Thanks again.

Injuneer

The 94 4L60E has a "switched" converter lockup. 95 and up has a pulse width modulated lockup. I doubt the LS1 PCM can control a 94 4L60E. Check with Cahall - he is very helpful and can address the issue. Might need a stand alone trans controller.

thenewkid

Thanks for you reply. I guess my next question is, would it be more practical to just find a whole front clip with a t56? the only mods I'm thinking about are nitrous and a new cam.. long tube headers if my wallet allows it.

Would anyone be interested in the lt1 I currently have?

Injuneer

A donor car with an intact front end is the easiest way to go.

Why don't you just work with the LT1 you already have? There are several things in the mods list that can easily be improved upon, depending on what you mean by "street ported heads", whether there is a cam to go along with the 1.6X roller rockers, the Edelbrock headers. I also suspect you have a 160* Hypertech t-stat, since 180* is stock. Appears you are using the Hypertech AFPR to increase the fuel injector flow rate, etc.

thenewkid

by street port, I just mean the runners/ports have been cleaned/gasket matched. They have already had a surface grind once and now 3 bolt holes need helicoils. I could have my shop do everything including a full port but I just don't know if its worth building these stock heads.

I Like the LT1 I'm just not sure how much the stock bottom end will take, So if I have to pull the engine it just seems more practical to put in a different one.

Also it'd be a cold day in hell before I ever want to mess with that opti/waterpump for the 3rd time... Is it even possible to swap a cam while the engine is in the car?

Injuneer

Ported stock heads, by a knowledgeable LT1 head porter, plus carefully matched cam, can produce 500HP at the flywheel. Stock rotating assembly can support that with no problems.

thenewkid

That's respectable and I'm sure the LT1 route is cheaper. I just feel like I would be happier in the long run with and LS1.

EDIT: Also, could the stock rotating assembly handle nitrous as well?

Injuneer

The stock rotating assembly is probably good for about 600HP, pushing it. Above that, the connecting rods are in danger. And the hypereutectic pistons are at risk with nitrous at that level.

thenewkid

Cahall said it wasn't practical. So I guess im keeping the LT1

On another side note, I' always looking for a 383 short block.

Injuneer

Check the "parts for sale" forum.

thenewkid

Ok so I noticed my waterpump is leaking again so I've decided on a cam swap along with ported heads/ intake and some long tube headers if I can afford them. My concerns are how much the 2 bolt mains/ stock timing chain can handle. Also, what sort of cam would best fit my setup. I don't know a lot about the 3000 stall

Injuneer

These are now becoming questions for the LT1 Based Engine Tech forum. I'll move the post there.

ACE1252

I would not think that the stock timing chain is an issue, but I suppose at some point a roller might be better. I opted for the stock timing set, but my best guess for what I'm making is around 400hp at the crank. Nothing but your run of the mill all bolt on/cam LT1(no suspension work or slicks of any kind yet).

First questions are generally....

How much power do you want to make?
How much $$$$ do you have to spend?

maybe2fast

Stock bottom end. cam and ported heads and some other stuff


https://www.camaroz28.com/forums/lt1...1-dyno-881036/

97WS6SCharged

2 bolt mains are fine for most builds. I wouldn't concern myself with changing them unless you're going with an aftermarket rotating assembly. Timing chain could probably stand to be changed as they do stretch over time and the newest Gen 2 motor is almost 18 years old now. A replacement stocker should be adequate, won't cost a ton like the LT4 set and won't require clearance work to the timing cover or using an electric water pump like a double roller.

What do you want in a cam? Drive-ability/fuel economy? All out power? Something in between?

One comment on your original question about the 94 transmission; why not use a 4l60e from a donor vehicle? They don't cost that much when you buy a complete engine/trans/wiring combo and all you would need to swap would be the tail shaft housing for the torque arm.