ScaryFast

Updates in BOLD

The swap is done! Thanks to all who helped. Specifically, Ch@os, COPO, 68steiny, 85Mike TPI and Steve85 were invaluable down the homestretch. Thanks guys!!

History: I've read through several threads but there is information overload, and they all seem to be tailored to a T56 or Auto trans. So I'd like the experts to chime in to help make a short, difinitive list of what parts I need to do the swap.

This is a gutted race car so this swap was a little less complex than on a street car. Here is the list of parts needed to make it happen.

The complete list now that the project is done:

1. LSx motor, pan to pump
2. Exhaust manifolds - this is a tricky one. Melrose makes conversion headers, but they're $900. I used stock manifolds from a 2001-2004 Corvette but had massage the passenger side to make it fit. See post 134
   LS conversion header link - http://vettaid.com/LSxPackagesKits.aspx
3. Harness - I had a custom harness made by jleonard.chevypro@yahoo.com
4. PCM - The best computer is the 1998-2004 GM. Easy to get and program.
5. Motor mounts - A few options here, vettaid makes some
6. Bellhousing - Quicktime PN RM-6039 Needs machining to work, see page 6, post 105
7. Accelerator pedal interface - F-Body cable drive TB with Lokar cable TC1000LS1 . Remove the end link and just use the button on the end for the pedal interface
8. Power steering - The C4 hose will thread right into the c5 pump; bend exisiting or make braided AN6 line
9. Alternator - LS alternator should work without modification
10. Fuel lines - Flip the LS rail and use existing C4 lines with filter in next item. Make a new line from the filter to the rail. See complete list of fittings here: http://forums.corvetteforum.com/1580651859-post14.html
11. FPR - stock c5 corvette fuel filter-regulator, WIX/NAPA part number 3373
12. CLutch - Stock LSx clutch
13. Clutch throw out bearing - McCleod 1345 YOU MUST LIMIT CLUTCH PEDAL TRAVEL!!!
14. C4 Clutch master cylinder is fine, but the pedal is a little stiff
15. Tach signal - signal wire is the pcm tach output wire, see post 15
16. Front crossmember mod pictures - not necessary on '92+ cars
17. Guages - My guages are all aftermarket Autometer, I run mechanical oil and water temp and oil pressure so I don't need that interface to the digidash. However, Vettaid has kits for street cars.

In return I will update this first post with links / PN's to the stuff you guys recommend to make it an easy reference for others. I am putting all the info above (with prices, etc) into an excel sheet. If anyone wants it PM me.

lt1396corvette

Here's a link to Melrose Motorsports that has the bell housing.It's made by Quick time,part # RM-6039.You can buy it from Jegs or Summit.They seem to be best price.There's other stuff on there too for the swap.I will be doing an ls1 swap in my 94 vette with a zf tranny.Good luck
http://www.melroseheaders.com/produc...ers/C4_LSx.php

jaa1992

IIRC ZFDOC was going to make a modified bell housing to connect the ZF6 to an LSx

Hmmm - what class are you going to chase with this one??

For the power steering you may be able to modify the DRM high pressure hose.
Good Luck!

ScaryFast

ST1 or 2, not sure...I just want the joy of an LS motor for the track. I haven't decided what to do with the 383, I'm just tired of running so damn heavy because it makes too much power. Dyno'd in July at 414 RWHP, about 50 more than I want. it's too painful to choke her back, so I started thinking about this project...I think I can do it for about $4000 and probably get that money back out of my current motor and extras if I decide to sell it.

dizwiz24

What parts are in your 383? Is this a high compression motor or a low compression one (for forced induction)?

dizwiz24

ScaryFast,

I know you didnt want a bunch of misc. questions, but I have to ask:

What are the advantages of a zf6 vs. A t56 on an LSx swap ?

Your ideas may give me ideas for my next build.

ScaryFast

Standard compression, 10.5:1. It's built for reliability over power. I'm probably leaving 50 hp on the table but it runs all day long without worry. It's a stout all forged motor.

It wasn't that I didn't want a bunch of questions, I was just trying to save the next guy (me in this case) from having to wade through 10 pages to get the info needed. I decided to solve that by updating the top post with links and info so that if this comes up in a search all the info is right there.

I chose a ZF6 because I have one. That's all. I may switch to a lighter trans someday, but for now there is no need. Stairman here on the forum has done the swap with a ZF, I talked to him Friday and he'll be sending me the ZF info today or tomorrow when he's home. I will of course share it here.

MickPB

Please share after you get the info from Stairman. I've got some suspension work planned for this winter but if that goes as well as I hope then an LS motor could be in the plans

wanabgts

I too have been looking for solid info on the ls swap with zf....thanks for the thread there is already alot of useful info here!

Zack

ScaryFast

Today's update:

I have heard two ways to attach the motor to the trans. I think the bellhousing listed above by lt396 works by itself. However, I talked to ZFdoc today and he did it differently. He used an F-Body bellhousing, made an adapter bracket, and also had to install a ZR-1 trans input shaft to make it reach. I'm hoping that's not required with the Quicktime bellhousing, but I'm not sure yet. Apparently the LS clutch and TO bearing assembly also work without modification.

I talked to tech support at Quicktime (they make the bellhousing) today as well, and the tech seemed to think it was ok without using the ZR-1 shaft, but didn't know for sure. I'm thinking it will take buying it and mocking it up to check the distances. I really don't want to pull the trans, I HATE the C beam.

ScaryFast

Short update - not much to report. Had to do a fuel pump change on the other car. Now that the space is free the C4 goes back in the garage tonight and updates should follow later this week.

littlesk8cracker

very interested, plan on doing an ls swap and im still unsure as to wether ill reuse my zf6 or switch to a t56

Kubs

Just move the LS2 from the C6 into Black Beauty! You better hurry up, Nationals is like 3 weeks away....

Did you find what went out on the 383 yet? If you part it out my dad may want some stuff for his '92.

cttech455

1. Power steering- I imagine you are going to use the corvette accessories on the ls engine which is the easiest way. The hose on you c4 will thread right into the c5 pump, but you will have to do some bending on the rigid part of the hose to get it to fit or get a braided high pressure hose from doug rippie motorsports like I did.

The vettaid motor mount adapters I believe are only for l98 cars. They are just plates that bolt on the side of the engine and then your stock motor mounts bolt to them. I believe lt1 motors are mounted differently. Check some of the lt1 to ls1 threads. People have adapted the c5 corvette pedestals to work and used volvo mounts.

3+4. You will use a stock c5 corvette fuel filter-regulator (its one unit). Mine is mounted in the stock location as the original filter. I ran -6an braided to the fuel rail. You could turn the fuel rail around if you want, I used a 180 degree hose fitting and left the fuel rail alone. I also upgraded the fuel pump with a high volume kit from racetronix as the ls engine requires about 58psi of fuel pressure.

7.Tach signal- I used a newer autometer tach with my swap. The signal wire is from the pcm tach output wire, in my case pin #10 on the red connector. Pcm connector pinouts are at chevythunder.com The tach has switches to be adapted to 4,6,or 8 cylinder engines. It needs to be on 4 for an ls engine. Then you need to amplify the 5 volt signal from the pcm so the autometer tach can read it (it needs more like 12) This is done by going to radio shack and picking up a 5 pack of 1/4 watt 4.7k ohm resistors for a dollar. One prong of a resistor goes on the signal terminal of your tach and the other on the +12 volt terminal. The resistors are very small.

ScaryFast

The T56 shifter location is dead center while the ZF6 is offset toward the driver. You can use the T56 (many here have) but more extensive mods are required to the car.

littlesk8cracker

ya trying to decide which would be easier, attatching the zf6 to the ls1, or cutting up the floorpan to make the t56 fit

miker2

the ls alternator has different spacing on the mounting holes than the vette bracket. the c5 power steering hose is a lot easier to tweak on the rack end--very minor bending required compared to the c4 hose. the c5 power steering pulley was a hair too large on my install--the belt wanted to rub on the k-member. i ended up making a pulley but there is a gm 12578552 thats supposed to work.

littlesk8cracker

appreciate the offer, but im nowhere near ready to start the swap haha. still in school and trying to make ends meet

COPO

Quick time bh housing fits fine on the zf to the ls. ls1 style clutch will fit fine. Ls7 fw/clutch will not fit. I haven't found a throw out bearing, but having one made is not a problem.

I used a lt k member with a auto c beam and c5 motor mounts and the bolts drop thru the holes like it was made for it. The stock ls rubber mounts are to tall and you will need to find some shorter. I made mine solid mount.

Kubs

What changed on the LT1 cars that makes the k member more desirable?

Andy, did you look into what Quartermaster has to offer for TO bearings? They several a couple different kinds and they can be ordered with different length pistons as well. When you guys find one that works with the ZF I will be interested!