LS4 Into an MGB

[Scott Costanzo]

Thanks guys.

Beat me to it, Scott.

I figured you'd have something to add Carl which is why I tried to beat you to it! 😊

I much prefer the new color of the fan cover/shroud.

Yeah, it's all new. I had to move the radiator forward a little to accommodate the Volvo fan so I decided to do it over rather than trying to adapt the original. It's very visible so it has to be right. I applied the lessons I learned from the first time too. I went with semi-gloss rather than satin this time. It's not perfect but I think it looks pretty good.

[standard32]

Nice job and thanks for all the documentation

I'm trying to get my head around balancer/crank/timing cover compatibility...

you posted this on page 9..... "I also replaced the timing cover. The main reason I did this was the original LS4 timing cover has the cam sensor positioned 180 degrees from the position of the RWD LS motors. Obviously, the signal from the cam sprocket reluctor will occur at a different time. I did a lot of investigation but couldn't tell if the 0411 looks at a rising edge, falling edge or just an edge and didn't want to take the chance of finding out the LS4 cover doesn't work when everything was together. An added benefit is the water pump fits without having to modify the timing cover. ....

If I'm understanding correctly, you are saying you still retain the original LS4 crank and cam ...but with a RWD timing cover?

If so, which RWD timing cover did you use? Or maybe they are all the same though?  (I haven't had any luck finding that info yet).... I worried that the truck timing cover would protrude too far and hit the balancer so that's why I was curious if that's a truck or a shallower version.

[Scott Costanzo]

Hey Kenny,

Thank you!

If I'm understanding correctly, you are saying you still retain the original LS4 crank and cam ...but with a RWD timing cover?

If so, which RWD timing cover did you use? Or maybe they are all the same though? (I haven't had any luck finding that info yet).... I worried that the truck timing cover would protrude too far and hit the balancer so that's why I was curious if that's a truck or a shallower version.

Yes, I'm using the original LS4 crank, cam, cam spockets/chain with an "LS2" timing cover. I took the old timing cover off and directly placed the new one on the motor. It was from a car motor I believe. I got it off of a guy on LS1Tech. The dimensions of the new timing cover appear to be the same as the LS4 cover (except for the position of the cam sensor) and it's been on the car for close to 5,000 miles now with no issues. I'm pretty sure the truck covers are the same and will interchange but you should double check that yourself before buying one.

You probably already know this but the original LS1 had the cam sensor at the back of the engine and with the LS2 it was moved to the front and placed in the timing cover. The LS4 is of the same "generation" as the LS2, in regards to the timing cover/position of the cam sensor at least.

Tell us a little about what you intend to put the LS4 into. It's ok if it isn't a British car. What computer are you going to use?

[standard32]

Thanks. I have a 34 Ford pickup and an LM7 5.3 (from a truck). Like you, I have a very tight physical space to fit it in... I made it worse by making my own front crossmember that sits a couple inches higher than the original (thus lowering the truck a couple inches.)  I don't want to cut any more than absolutely necessary on the firewall, so I'm trying to make the engine as compact as possible.

After digging around on the internet, I stumbled on to the front wheel drive LS4 balancer. I just bought one and am anxious to try to put it on. Through cross referencing dimensions for part numbers, I found that the LS4 and LM7 balancer share the same inner diameter and it should fit. But, the LS4 crankshaft is 10mm shorter....meaning the LM7 crank will stick out 10mm further.
I am thinking that, if I'm lucky, and the depth of the balancers is the same where it fits on the crank, I might be able to solve this problem by making a spacer that is clearanced to slide over the crank to allow the bolt to tighten against the balancer.

I will have to do some searching on the timing covers. That is definitely helpful to know that an Ls2 timing cover worked with the LS4.

I am very new to LS stuff. I'm just sort of going at it with the mentality of working my way through it and trying to figure out as I go.
I plan to go with a carb rather than the fuel injection though.

Here are a couple before/after pics where I made tubular crossmembers and how much tighter it is around the balancer now.

[Scott Costanzo]

Very cool project! Thanks for sharing. I really like your garage too!

I'm quite sure that you'll be OK with the truck timing cover. I'm just cautious with advice because I don't want to lead someone down the wrong path. I didn't take any measurements but the crankshaft was still recessed into the pulley when it was fully seated on the LS4 crank. I'm not sure there was 10mm of space left but at least there was something there.

Keep us informed how this works out for you if you don't mind? I think this will be very useful information.

[BWA]

Hello Scott it has been a while since i have talked to you.
I have been driving my TR6 (Gm 3400 v6 engine) for a while now and I have 2900 miles on it now.
When I switched out the TR6 diff which I had set up with a reluctor wheel and a 2003 Olds Alero vehicle speed sensor I installed a Nissan r200 diff and I used one of the abs sensors for a vehicle speed sensor.
It seems that the Nissan abs sensor does not talk to the ecu and the air idle control system is not working as well as it could.
So I am looking at re-using the Alero speed sensor.
The alero speed sensor has two wires one is yellow and the other is purple.
The last time i used this sensor I did not pay attention to these colors and I hooked up the sensor to the two wires that go to the ecu.  
Now I am wondering if I need to make sure the wires goes to the proper connectors on the ecu.
Or does it make any difference?
When you set up the vss for the ls4 engine did you have to make sure that each wire went to a respective hookup on the ecu?
This stuff drives me nuts anyways thanks for your time and consideration.
Cheers
Byron

[Scott Costanzo]

Hey Byron, I'm just seeing this. Can't believe it's been two years since there has been a post to this thread! Time flies.

When I did mine, I did some research to make sure I wired it correctly. I'm not 100% sure it makes a difference but I can tell you that my VSS works. My cruise control works and the speed shows up in my logs. What ECU are you using and what operating system is installed on it? There should be tags on the unit with that information. Are you able to log and are you sure nothing is being returned? I can tell you that the configuration in my ECU has been updated to account for the pulses I send to it with my 4 tooth reluctor. It may be helpful to determine the number of pulses per mile the code you have in your ECU is expecting and then compare it to the number of pulses/mi you're generating with your setup. It is possible the pulses you are generating are too low or too high to be recognized by the code in your ECU. I had that happen with my V6 ECU.  

Let me know if you have any other questions.

Hope you've been doing well.

Scott

[BWA]

Thanks Scott for your reply.
I dug into the GM manual that my friend copied to do the electrical on my car.
The manual shows that the two wires at the ECU are purple and yellow which match the wires on the VSS.
Today I am going to switch the wires where I spliced the Nissan abs sensor and see if there is any change.
If nothing changes I am going to fab up a bracket and mount the GM VSS and make sure the wires are connected properly.
The reluctor wheel will be the mounting hub on the passenger side of the diff, this hub has six lugs.
The original setup had a reluctor wheel with 8 blades and it seemed to work better than it does now.
Hopefully it will work with six lugs.
I will keep you posted as to what happens.
Cheers
Byron