Stocki'ish LM7 rebuild?
11-26-2012, 08:34 PM
#1
Launching!
Thread Starter
Stocki'ish LM7 rebuild? Hey guys n gals,
I have been searching for a few days now, but nothing seems to pop up, so if it was covered I am sorry!
I am putting a 5.3 LM7 into a 1998 Range Rover, and with all the other issues I will have (never done before AFAIK), I dont want motor issues too.
I am doing it due to the high cost of getting over 250hp out of the lethargic 4.6's they have, and have rebuilt quite a few of them as a side business. The offerings are pretty slim, so choices are easy to make on that motor.
The LM7 is currently stripped and at the machine shop (block, crank, heads) for some basic machining and measuring. What would be a simple, but good bang for the buck, rebuild to do? Consider this is being used in a 4k lb permanent 4wd SUV, so high peak HP is not a concern.
It will be getting new pistons/rings, bearings, ARP head studs, oil pump and cam/lifters. Heads are going to be surfaced, so no real bump in CR to speak of, crank will be polished if it mic's OK, and the cylinders at least honed if there is very little runout. Engine had 108k miles on it and no signs of HG issues etc. Just a little dirty inside from lack of good oil before it was pulled IMHO.
Exhaust will hopefully be the OEM (2001 Tahoe) manifolds, mated to the Range Rover exhaust.
Suggestions on a good, basic and reliable rebuild? Parts? Best suppliers?
I have seen the "rebuild kits" on Ebay, but am a little apprehensive about their quality. Anyone have experience with them? I have always ordered name brand stuff for the motors I have built in the past, and it served me well. Obviously with a swap like this, cost is a factor
Any and all suggestions welcome. I am sure to have a crap load of questions down the road, but this will do for now!
Many thanks in advance.
Martin
I have been searching for a few days now, but nothing seems to pop up, so if it was covered I am sorry!
I am putting a 5.3 LM7 into a 1998 Range Rover, and with all the other issues I will have (never done before AFAIK), I dont want motor issues too.
I am doing it due to the high cost of getting over 250hp out of the lethargic 4.6's they have, and have rebuilt quite a few of them as a side business. The offerings are pretty slim, so choices are easy to make on that motor.
The LM7 is currently stripped and at the machine shop (block, crank, heads) for some basic machining and measuring. What would be a simple, but good bang for the buck, rebuild to do? Consider this is being used in a 4k lb permanent 4wd SUV, so high peak HP is not a concern.
It will be getting new pistons/rings, bearings, ARP head studs, oil pump and cam/lifters. Heads are going to be surfaced, so no real bump in CR to speak of, crank will be polished if it mic's OK, and the cylinders at least honed if there is very little runout. Engine had 108k miles on it and no signs of HG issues etc. Just a little dirty inside from lack of good oil before it was pulled IMHO.
Exhaust will hopefully be the OEM (2001 Tahoe) manifolds, mated to the Range Rover exhaust.
Suggestions on a good, basic and reliable rebuild? Parts? Best suppliers?
I have seen the "rebuild kits" on Ebay, but am a little apprehensive about their quality. Anyone have experience with them? I have always ordered name brand stuff for the motors I have built in the past, and it served me well. Obviously with a swap like this, cost is a factor
Any and all suggestions welcome. I am sure to have a crap load of questions down the road, but this will do for now!
Many thanks in advance.
Martin
11-26-2012, 08:50 PM
#2
If your just doing a basic run of mill rebuild then I would trust the guidance of your machine shop as far as what parts to use and what parts he would warranty. In your case a hypereutic piston will be fine. Head studs are kinda overkill for what you are doing. I would just stick GM bolts back in it. The 5.3's and 4.8's are pretty stout in stock form as is, so I would be half tempted to just throw it back in with stockish internals and let it ride. You most definately will be making more power than you would have with the 4.6. Not sure how stout the Land Rover driveline is, but if you start getting crazy with power you might find a bunch of weak areas there.
11-26-2012, 09:00 PM
#3
Launching!
Thread Starter
They just had a fire, at the machine shop, so their parts department is a little scarce right now!
If an Ebay rebuild kit ill work, then I will go that route. My main concern is the make of the rings and bearings. If I can get name brand stuff there, it will save some coin.
The 4.6's are a decent enough engine, for a 40+yr old design! They were originally the Buick 215 all aluminum motors, then just got bored and stroked every few years to end up being a 4.6. Boy did I notice the weight difference when I picked up the LM7 block!
The transmission is also a concern of mine. The diffs and transfer case are pretty stout items, but the OEM ZF4hP24 is the limiting factor. I will be rebuilding it, as it has 235k miles on it and never been touched besides fluid and filter changes. So hopping it up to some 400BHP fire breather would bite me in the rear for sure.
I always use ARP studs in the motors I build, so it's just a habit I guess...Will price them up and compare to the OEM stretch bolts.
Martin
If an Ebay rebuild kit ill work, then I will go that route. My main concern is the make of the rings and bearings. If I can get name brand stuff there, it will save some coin.
The 4.6's are a decent enough engine, for a 40+yr old design! They were originally the Buick 215 all aluminum motors, then just got bored and stroked every few years to end up being a 4.6. Boy did I notice the weight difference when I picked up the LM7 block!
The transmission is also a concern of mine. The diffs and transfer case are pretty stout items, but the OEM ZF4hP24 is the limiting factor. I will be rebuilding it, as it has 235k miles on it and never been touched besides fluid and filter changes. So hopping it up to some 400BHP fire breather would bite me in the rear for sure.
I always use ARP studs in the motors I build, so it's just a habit I guess...Will price them up and compare to the OEM stretch bolts.
Martin
