I have not posted on this board about my swap, but the engine is being assembled at the machine shop and need some help on the finer details.

Here's the run down.....

6.0 iron block, re-using crank, rods, pistons. Having all new bearings installed (incl cam) having the machine shop build the short block. Just align hone the cylinders, polish the cranks, measure tolerances for correct bearing sizes, and of course new piston rings.

Using a LS1 hot cam.
L92 cylinder heads, with stock rockers, and ls6 springs.
LS3 manifold, ect.

With the lower comp ratio, I am hoping for a modest 400-450 crank hp.

I am going to use a drive by wire throttle body.
Also using my built 700r4 trans

So here are my questions. What PCM and wire harness should I buy (crank is 24x reluctor). And what modifications will I need to make to the harness? I know obviously were going to be dealing with PCM tuning ect.

How will I mate the fuel feed line to the manifold.

Will stock motor mounts work with the Spohn mount relocators?

What about exhaust? Some LS manifolds, or headers....

This is a "budget build" and do not want it to run away from me.

Basically, for those of you who have done this swap, what small time consuming things do I need to prepare myself for?

I am considering yanking the 350tpi very soon, and getting the engine compartment ready to go and to handle the small bits right away before the motor is done.

Please fill me in. Its very hard to search the forums to gain all of this info individually?

Once we dive into the motor install I want this to go as smoothly as possible!!

And when done I want this to be a fun little vert

 

for startersread the lsx swap sticky over several times.

you will need to get a hold of an ls1 fbody or a swap oil pan and all the associated parts there, pickup, etc.

the throttle body, wiring , ecm and dbw pedal should all come from the same donor vehicle if at all possible. the ecm from the 99-02 fbody wont support the dbw stuff, so the best bet there is probably the same year truck as your engine came from. again, get the ecm, tac module, and pedal all at the same time, and harness too if you can. if you are gonna do the harness yourself, just find the wiring diagrams and start tracing out what everything is. its not too hard, but it is time consuming. you have to weigh your budget vs the cost of your time to get it figured out.

start searching car-part. com and ls1tech for accessory brackets. the f-body stuff should work, although the ac compressor will have interference issues. see the sticky and search here, you'll find all the info you need.

read a ton, there are great build threads here that will cover most all the issues. mostly read and take notes. there are many issues that you have to just decide what you want to do, so arm yourself with all the mistakes and knowledge written here and it'll be all good.

 

Get a custom cam for your setup. Hotcams wake up a stock/mild engine and yours is neither

LS3's are all DBW, cable conversion means aftermarket TB or adapter plate. Neither are very budget oriented

The 700R4 can be built to handle the power, but it wont live very long behind the massive torque the 6.0 consistently puts down. TH350/400, 4L65E, 4L80E or better fits the bill, but its your car

Use any LS series car or truck harness. They all require mods. Find a cheap one and go with it

Read:
https://www.thirdgen.org/forums/ltx-...p-3rd-gen.html
https://www.thirdgen.org/forums/ltx-...rt-finish.html
https://www.thirdgen.org/forums/ltx-...formation.html

Diagram in the additional info thread. Use all or part of it

Mounts are wide open. Aftermarket C style reuse the LS1 engine side mounts, plate style reuses everything SBC. You can modify stock SBC mounts to LSx engines without anything aftermarket if you're crafty with a welder. The trans crossmember also changes for the swap, dont forget about it. Most people end up building their own for exhaust clearance, torque arm mounts etc

Fbody manifolds are the most common aside from the swap longtubes

Budget LSx is a risky venture, esp when you dont know exactly what to expect

Leave the original engine alone until you are ready to do the swap. Most build threads are over several months because all the ducks were not in order before disassembling the car. Most simply didnt know of the hurdles, but some needed extra time for prep like undercoating and bay painting

Gathering parts should be done via checklist
Get your engine ready in Fbody dress (pan, accessories, etc)
Get the trans, converter, starter, flexplate, bolts etc
Have the harness ready or even installed on the drivetrain and a rough tune in the PCM
Build the fuel system off the car and be prepared to install once the TPI is out
Nab a spare K-member and notch it in case the mounts dont let the oilpan clear. Some swaps need the notch, others are just fine without
Have atleast some idea of how the exhaust will run

This knocks the biggest issues out, you should be able to do the swap and start the engine up in one long day

 

You could start with a truck harness, and use an LS2 or LS3 throttle body. You'd also have to use the gas pedal from the DBW vehicle too. When it's all said and done, I don't know that this option will really save you much, if any money.

Your best option is probably to just scan the classifieds and ebay for the right throttle body. There are guys selling used aftermarket cable throttle bodies all the time. Another option is to look at the FRE 90mm cable throttle body... it's only about $275 brand new.

I'd also reconsider your cam selection. Do some real homework on cams for this motor. L92 heads seem to favor a split pattern cam because their exhaust flow isn't quite up to par with the intake flow. I'm not sure what impact your low compression might have, but because of it, your car may be best off with somewhat non-typical valve event timing, especially if you want to maximize low and midrange torque.

 

I must disagree. The HOT cam is a fine choice. It is split pattern, and with it's modest lift, it makes it easy to get the valvetrain geometry correct. In fact, GMPP is offering a crate LS3 with the HOT cam, rated at about 480 horses, and they offer a computer and wiring harness for it. The issue is you have 24X instead of 58x. I'd spend the $300 to change the crank, and the difference in bore diameter won't be a problem for the computer.
Neither will your slightly lower compression.
On the other hand, those heads would like a 220/228-114 581/58? cam, because the flow keeps increasing right on up through 0.575" intake valve lift. This cam would squeak through an emissions test, but nothing wilder. even going to a 113 lobe sep could cause you to fail.
As for a 700R-4, most aren't up to it, but I have a BTO level 2 that I bought used, and since then I've put nearly 200,000 more moles on it, including a summer in my '88 Camaro that ran low 10s at the dragstrip. BTO's level 3 is rated to 620 ft-lbs of engine torque, so getting a 700R-4 to survive is possible.

 

first off. the ls6 springs are incorrect. get some comp 918 minimum, but for a few $ more might as well go with PRC or PP duals.
the l92 intake valves are significantly heavier than the cathedral port valves.
the hot cam will work fine since its heavy exhaust biased.
use ls2 head gaskets.
can also use ctsv pan.
reuse 6.0 flexplate with spacer for use with 700r4 and new converter.

i make brackets that allow use a tbi alt, and plu to your existing wiring or run with 1 wire. also make the bracket that allows use of gm tc ps pump. cheeper than actual ls pumps, but same design in aluminum casting, remote fluid resvoir like lt1.
bolts on with truck wp and crank pulley but can also be used with car wp(what u will need since going efi stock manifold) with slight, easy mod to wp.
no need to use ls1 fbody or c5 accesories any more in 3rd gens.

if using ls3 rail and injectors and manifold, the c5 fpr/ff is your lowest priced option. run single feed line from fpr/ff to rail. no need for return at the rail or fpr.
Morris Motorsports (very good friend of mine btw) has the cable drive 90mm ls2/ls3 4 bolt pattern cable drive tb for 275$ new.

headers. shorty or stock manifolds will work great for what your building.
if need lt, diy is the best option.

 

Thank you very much for the info, as this is what I am looking for.

Responding to all posts here.

I already have the LS1 f-car oil pan, tray, and pickup and new oil pump already. So I am stuck there.

Why the LS2 head gaskets?

Where can I find info on the flexplate spacer? and why do I need a new converter, mine has 3,000 miles of use since my 700r4 build?

I am interested in the bracket to re-use my alternator, and is there anything that allows the use of my current PS pump?

I'm going to find a car LS water pump.

I am going to stick with the 24x reluctor crank (im not pushing for a new crank)

I think I will end up with stock LS3 Camaro manifolds for my build.

Now, knowing I am going to stick with drive by cable and a 24x reluctor, which ecm # and harness(I cant decide to work a used one or buy a custom.....)

The answers I am looking for are, which fuel pump to buy, going to go with the c5 fpr/ff.

electrical above.

motor mount configuration?

Am I going to modify my trans crossmember and have any driveshaft issues?

once again, I am going to stick to most of my guns on this as I do not want a run away money train.

Machine shop verified, need align hone only, pistons are still round and re-usable with this block, and a crank polish, not too bad on a 170k lq4 that was well maintained. They will also check my used under 10k l92 heads tomorrow.

Thank you to all of you for your time here. I will make this my build thread.

 

I am also building two of those crafty checklist that list parts and the other for when the stab begins........ "ducks in a row"

 

Look at the engine side of your torque converter. See that nub in the center? That's different than the nub on LSx-specific torque converters, so you'll have to change the torque converter. As for the spacer, GM offers one, as do Hughes Performance, TCI, and others. But if you just use an LM7 flexplate, you shouldn't need a spacer, as the LM7 flexplate is a bit bowl shaped.

 

LM7 plate doesnt help anything. The early transmissions pilot is too short.

Ive got a hughes perf. spacer in my tool box if your interested in it. Had it in my LM7/700R4 setup at first, then switched up to a 4L65

 

id be interested, send me a pm and we'll seek terms!

 

So with this spacer, am I going to need any sort of starter setup?

 

Spacer is a misleading name for it. It goes between the flexplate and conveter and doesnt space anything out, it receives the converter snub. Use the stock starter

 

the oe 6.0 piece locates between the crank flange and oe flexplate. generally known as a "spacer". im not sure what your talking about.

 

http://www.ls1tech.com/forums/automa...0r4-4l60e.html

Nearly every site selling the spacers says to put the flexplate on first then the spacer then bolts. Its main job is to receive the converter snub, not move the flexplate