old66tiger

Hey Everyone.

I have a 66 GTO convertible that is completly restored and sporting a 461 Pontiac roller motor. The engine is EFI and puts out about 550 HP at the crank. The engine is a beast and really propels the car down the road nicely. However, as i am getting older and more set in my ways, I want to move toward an LS conversion in the car. The car is a 5-speed car so I plan on keeping that trans and just swap to an LS engine.

There is SOOOOOOO much information on this forum that it just makes your head ache. So, I would like to do some homework up front and I hope that I can get some of the veterans of the LS swaps to give their input.

Let's start with a 30,000 foot look at this project. I was thinking of going with the GM crate 525 hp engine from Pace. This thing is pretty incredible and should be docile enough to have nice street manners.

http://paceperformance.com/i-7739382...te-engine.html

Anyone using this engine?

I was going to control it with their harness kit:

http://paceperformance.com/i-7788424...s-sensors.html

Anyone have any idea how long this harness is? Can I mount the ECM up by the battery? Does this directly control the fuel pump or do I still need a relay. Not sure if the 255 lph pump will be enough for this engine. I would think so.

Dirty Dingo LS mounts look like the hot ticket and should give me some adjustment.

As far as the pan, I am stuck here. GM offers a muscle car pan and Holley offers the new LS pan. Then there is the Autokraft pan. I just need something to clear the frame and allow the steering to function properly.

This serpentine from GM looks like the ticket.

http://paceperformance.com/i-6255430...7-engines.html

Not sure about if the PS pump pulley will hit the steering box. Anyone have experience here with that?

Lets start here and see where we go and what questions come up.

Thanks for everyone and their knowledge. This is new to me and am trying to learn as much as I can.

1989GTA

Here are a couple of thoughts.

1. Look into whether or not your transmission will bolt up.
2. Nothing wrong with that motor at all. If you add long tube headers you will see a power increase across the board.
3. I have seen that harness and the wiring should be long enough.
4. Yes, it controls the fuel pump. Can't remember on the relay. That is a minor issue however.
5. The 255lph should be plenty. I am running one and putting down more power without an issue.
6. The Dirty Dingo mounts will allow you to slide the engine back an forth to obtain the best clearance. If you decide on headers, have them on before you bolt down the mounts for the final time.
7. Yes the serpentine belt is the way to go. That setup will work.
8. Not sure on the power steering pulley but that setup looks like it would clear. It appears to have more clearance than I had.
9. If it was me I would use the new Holley oil pan. I am using the old one and had to but in steering stops. I still have plenty of turning radius.

By the way I have a 1965 Buick Skylark, so virtually the same car.

old66tiger

The transmission should bolt up. It looks like Hurst Drivelines sells the bellhousing for the TKO and my new Legend is a identical bolt pattern.

http://www.hurst-drivelines.com/?pro...cover-hardware

Looks like it would work???

Are you running the Walboro unregulated?

old66tiger

Any of the pans offer a npt bung? I am running an oil temp sensor and it would be nice to keep that feature. I think I can pull oil pressure off the back of the engine. Is there any other oil port that is not used?

dondb

iTrader: (1)

The holley LS swap 302-2 or 302-1 oil pan has a spot you can put your old oil sensor on….i blocked mine off and used the one on the back of the intake. I used the PSI conversion harness and it came with a fuel pump relay…not sure on the Pace one.

ijimmy

your trany solution

http://paceperformance.com/i-6535763...to-500-hp.html

as far as a pan , the holley 303-2 , is "supposed" to fit

old66tiger

Do I need a fuel pressure regulator? I would assume so. I was thinking of mounting it back by the tank and running a single line to the front with no return. Looks like I should not be running a vacuum reference unless I am boosting the engine. Thoughts?

oldgoat69

You can use the Corvette filter with regulator. Search the site for a gull run down.

1989GTA

Yep, the Corvette filter/regulator combo. Here is one with the fittings as an example. Yes mount it close to the tank.

http://www.speedwaymotors.com/LS1-Fu...Kit,41791.html

old66tiger

Thanks...That is the ticket. Although, it looks like any time you change the filter, you are in it for a complete assembly

Where are guys putting the ECM and fuse panel? I was thinking about drivers side by the battery, but when I got the lengths of the harness, it will not be long enough. I was thinking Speartech harness for a custom installation. I really don't want to put the ecm and the fuse panel in the car...holes in firewall make me nuts. Unless there is an inconspicuous spot somewhere.

1989GTA

"Where are guys putting the ECM and fuse panel? I was thinking about drivers side by the battery, but when I got the lengths of the harness, it will not be long enough"

That is where I put mine. However I moved the battery to the trunk. My harness was out of a 2007 Escalade and no problem with the wire lengths.

john 67

try looking at the mast oil pan . it seems to have the most clearence up front where you will need it .I used a modified f body pan from street and performance about 8 years ago , works fine but now there are a lot more options .JOHN

old66tiger

I saw those harnesses. They are actually pretty reasonable. Will they do custom lengths?

oldgoat69

I am using the E40 PCM, which is the same layout as the one you have listed, looks like it also uses the 05/06 GTO pedal. I mounted the PCM under the DS fender on the inner fender along with the TCM. Real estate in my engine bay is limited due to the supercharger aftercooler tank and plumbing, but similar to your car. I would be happy to send pictures if that helps. I used MSD rubber feet/insulators to mount the PCM/TCM. I made my own harness out of a truck harness.

dondb

iTrader: (1)

I'm not sure give Jon a call…very happy with the harness and service from them. Actually got to start the car Thursday night! Was only able to run the car for a short time because of the open headers noise. I live in a neighborhood and i didn't want to **** anyone off with school kids.

old66tiger

Yes, please. I would love to see pictures.

oldgoat69

Alot going on the picture, looks like lots of wires going everywhere.
I have the intake partly off replacing the cam sensor, and tore 1 of the intake seals. Oh well story of this project. I also just replaced the AC compressor for the third time and completed the charge to have the liquid line explode right after some really nasty noises from the compressor. I think the valve plate in the compressor gave up.

donnie_19

You can get your oil pressure sensor from the back of manifold or down my the oil filter with one of these adapters.

old66tiger

Cool. I talked with speartech and they can make the harness any length I want for about $1000 or I can go with a PSI harness for about half of that. Only catch is that the PSI harness has to go through the firewall. I still need to get over the phobia of cutting into the firewall. I have a regular heater box and may upgrade to AC in the future. Not sure on that one yet, so if I go through the firewall, I have to pick a spot that will clear the factory box and the vintage air box.

oldgoat69

Depending upon where you want your PCM to go you may be able to use an existing hole in the bulkhead. It may require unpinning the connectors to fish through, but the hole would be much smaller. If the plan is to go DBW the spot the current pedal attaches to the bulkhead would be an ideal location.