LM7 5.3 verses 5.3L LC9
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LM7 5.3 verses 5.3L LC9
I'm in the process of converting a 1956 Chev Handy Man station wagon 350/350 to a LS 5.3 3ngine. My goal is to have a solid sharp cruiser and to maximize the mpg range. To date I have located a complete 2004 LM7 5.3L engine and a complete 2007 5.3L LC9 engine for a swap out.
To cut to the chase which of the two applications will give me greater options for tuning and ease of conversion? They say the LC9 engine is a drive by wire verses the LM7 having more varied after market applications.
Are their known issues/concerns with with either set up?
Going super fast and quick is not the goal. Either engine over the SB 200 horse 350 will be a vast improvement.
Thanks for the feed back.
To cut to the chase which of the two applications will give me greater options for tuning and ease of conversion? They say the LC9 engine is a drive by wire verses the LM7 having more varied after market applications.
Are their known issues/concerns with with either set up?
Going super fast and quick is not the goal. Either engine over the SB 200 horse 350 will be a vast improvement.
Thanks for the feed back.
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Be sure to check which computer the 2007 motor comes with. If its the E38 ecm you will need the body control module to get any kind of signals from the computer for your gauges. I would go with the 2004 motor if you cant confirm which ecm the newer one has. This is just the surface of the differences that there are in the ecm's and other associated electronics.
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Thanks for the heads up. It appears that the LC9 might be to technical of a swap to put into a 56 Chevy. From what I read it seems that the LM7 has more versatility in going forward.
Appreciate the advice!!!
Appreciate the advice!!!
#6
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Be sure to check which computer the 2007 motor comes with. If its the E38 ecm you will need the body control module to get any kind of signals from the computer for your gauges. I would go with the 2004 motor if you cant confirm which ecm the newer one has. This is just the surface of the differences that there are in the ecm's and other associated electronics.
#7
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The LC9 uses an ECM with a TCM for both 6sp and 4 sp autos. The TCM for the 6sp is inside them.
The LM7 is a Gen III and the LC9 is a Gen IV.
Both are DBW. The LC9 will not have a TAC box. And will have returnless rails. The LM7 that year will have a TAC and may or may not have a return.
Either is just as easy a swap. No really advantage of one over the other with the right ingredients. The LC9 is an aluminum block and will have AFM.
If you going for max MPG your really need an overdrive trans as well.
The LM7 is a Gen III and the LC9 is a Gen IV.
Both are DBW. The LC9 will not have a TAC box. And will have returnless rails. The LM7 that year will have a TAC and may or may not have a return.
Either is just as easy a swap. No really advantage of one over the other with the right ingredients. The LC9 is an aluminum block and will have AFM.
If you going for max MPG your really need an overdrive trans as well.
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#8
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Be sure to check which computer the 2007 motor comes with. If its the E38 ecm you will need the body control module to get any kind of signals from the computer for your gauges. I would go with the 2004 motor if you cant confirm which ecm the newer one has. This is just the surface of the differences that there are in the ecm's and other associated electronics.
The LC9 uses an ECM with a TCM for both 6sp and 4 sp autos. The TCM for the 6sp is inside them.
The LM7 is a Gen III and the LC9 is a Gen IV.
Both are DBW. The LC9 will not have a TAC box. And will have returnless rails. The LM7 that year will have a TAC and may or may not have a return.
Either is just as easy a swap. No really advantage of one over the other with the right ingredients. The LC9 is an aluminum block and will have AFM.
If you going for max MPG your really need an overdrive trans as well.
The LM7 is a Gen III and the LC9 is a Gen IV.
Both are DBW. The LC9 will not have a TAC box. And will have returnless rails. The LM7 that year will have a TAC and may or may not have a return.
Either is just as easy a swap. No really advantage of one over the other with the right ingredients. The LC9 is an aluminum block and will have AFM.
If you going for max MPG your really need an overdrive trans as well.
#9
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The BCM isn't really needed. Unless your using the stock gauge cluster or cruise control or TUTD function of the 6sp on a truck tune. Most those can be over come though so no big deal. The LC9 will use an E38 in stock form. He may be talking about a tach function.
Last edited by Bo185; 11-05-2012 at 11:21 PM.
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Well I have 99 Isuzu Amigo it has a tach and coolant temp gauge .How difficult wil it be to get a signal to them, or would it easier just to get all new gauges and go mechanical. The engine would be new body style 2007 truck 4.8 LY2 or 5.3 LH6 and keep it stock except headers.Oh yea I will be running a manual trans behind it.
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Regardless which engine I go with (LM7 or LC9) it will have a 4L60E overdrive trans behind it. At this point I'm assuming that the transmission modular/electronic controls will be part of the of the ECM which can be tuned for tire size and rear gear ratio.
I plan on using the stock gauges. Not sure what that would entail with the donor harness or if I'll have to go with mechanical gauges.
Given the LC9 does not require fuel return lines can I get by with a external pressure controlled electric fuel pump? I have a new fuel tank and would prefer not to have to install a fuel pump in the tank.
Any thoughts or suggestions are appreciated....
I plan on using the stock gauges. Not sure what that would entail with the donor harness or if I'll have to go with mechanical gauges.
Given the LC9 does not require fuel return lines can I get by with a external pressure controlled electric fuel pump? I have a new fuel tank and would prefer not to have to install a fuel pump in the tank.
Any thoughts or suggestions are appreciated....
#12
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Trans controls are in the ecu and can be tuned.
The stock mechanical speedo will be a problem. You can use an expensive modified trans tail with mechanical speedo output or a cable x box. Just use the original senders for the other gauges.
Either motor can be easily setup for a retunless system. External pumps work well on tall, deep tank. They tend to starve for fuel and suck air on flat, shallow, unsumped tanks ie. 68-72 A body. What's yours look like?
The stock mechanical speedo will be a problem. You can use an expensive modified trans tail with mechanical speedo output or a cable x box. Just use the original senders for the other gauges.
Either motor can be easily setup for a retunless system. External pumps work well on tall, deep tank. They tend to starve for fuel and suck air on flat, shallow, unsumped tanks ie. 68-72 A body. What's yours look like?
#13
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fuel tank
Given it's a station wagon the tank sits between the rear axle housing and spare tire compartment making the tank deep however, with a flat bottom. Their appears to be no baffles in the tank.