LS7 crate in C5, reliable?
Team Owner
Joined: Jul 2004
Posts: 24,652
Likes: 298
From: NJ
St. Jude Donor '05-'08
If you have your heart set on a LS7, get an LS7. It is an assome engine. The 58x to 24x crankshaft encoder wheel is no big deal! You don't have to pull the crank and change it. There are boxes to make it easy. Yes, other things have to be changed, but non of them are that bad. Dry sump would be the way I'd go. You need to move thing to make room for the tank.
My second choice to the LS7 would be the newer 480 HP LS3. Both engines as recieved have great reliability.
My second choice to the LS7 would be the newer 480 HP LS3. Both engines as recieved have great reliability.
LS3 is another very good choice.
Thread Starter
Former Vendor
Joined: Oct 2006
Posts: 7,331
Likes: 61
From: Port Huron MI
Thanks! Looks like LPE has all the bells and whistles! Not sure they would install a stock LS7 for me however and would probably be a couple arms and legs. How often do you guys run across a stock used LS7 that you pull out for some power hungry customer? 
If you could, shoot me a PM with a rough price to get a stock LS7 in my car, of course price of the used longblock up in the air. Thanks! 
If you could, shoot me a PM with a rough price to get a stock LS7 in my car, of course price of the used longblock up in the air. Thanks!
Premium Supporting Vendor
Joined: Mar 2001
Posts: 5,241
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From: Knoxville Tennessee
I've gone down the engine modding route with my WS6 before I got the vette and loved it, however I hated the reliability it lacked. Was always having some issue and worried about others. (forged 347, APS TT) I LOVE the reliability of my C5 being stock with bolt ones but coming from 667 rwhp auto WS6 to this is quite the change as you can imagine. Looking for the best route I add some ponies and keep my reliability that I have now IF possible. Of course I understand I will have to loose some because more pwoer will stress everything else such as the driveline. After looking at my options I thought of a blower kit, heads/cam, etc and both of those I believe will hinder my reliability a lot either losing driveability, stressing valvetrain, or stressing the stock bottom end in a blower app. I know some people on here have had zero issues at xxxx miles on their blower set-up but for the average Joe, being there myself, I know that's not the case in most scenerios. So I've come to one option I thought MIGHT work for what I'm looking for..... LS7.
With this, was seeing if I could find a stock LS7, add the headers to it, keep my vararam, and see some good ponies with stock GM reliability. Obviously a clutch would be in order but GM has that solution as well with the LS7 clutch. I don't really see what else could be an issue if properly swapped with a crate engine reliability wise. Would I be dipping into my reliability if I wanted to toss a BABY cam in it? What do you guys think here? Is this a pretty good solution? Give me your thoughts, and ALSO, what all is needed for the swap besides the engine and clutch? I know some wiring changes for cam sensor and such are in order, anything else major though? Thanks!
With this, was seeing if I could find a stock LS7, add the headers to it, keep my vararam, and see some good ponies with stock GM reliability. Obviously a clutch would be in order but GM has that solution as well with the LS7 clutch. I don't really see what else could be an issue if properly swapped with a crate engine reliability wise. Would I be dipping into my reliability if I wanted to toss a BABY cam in it? What do you guys think here? Is this a pretty good solution? Give me your thoughts, and ALSO, what all is needed for the swap besides the engine and clutch? I know some wiring changes for cam sensor and such are in order, anything else major though? Thanks!
Not sure where you are located, but I can put an engine package together for you, even build you an LS7 that would be perfectly reliable. If you were going to ditch the dry sump setup you might as well build a new engine by the time to resource the parts necessary to do it.
As someone mentioned you need to change the reluctor on the crank as well. Timing set, front cover, the list goes on and on. I can do it for you if you have your heart set on it, but I am sure I could build you an engine and install it for what you are going to spend on just the crate motor and retrofit with a dry sump.
Thread Starter
Former Vendor
Joined: Oct 2006
Posts: 7,331
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From: Port Huron MI
I am putting a drysumped LS7 in my 1999 C5 and there is a LOT of custom work being done to make sure the dry sump fits. It is not something that you are just going to put in there.
Not sure where you are located, but I can put an engine package together for you, even build you an LS7 that would be perfectly reliable. If you were going to ditch the dry sump setup you might as well build a new engine by the time to resource the parts necessary to do it.
As someone mentioned you need to change the reluctor on the crank as well. Timing set, front cover, the list goes on and on. I can do it for you if you have your heart set on it, but I am sure I could build you an engine and install it for what you are going to spend on just the crate motor and retrofit with a dry sump.
Not sure where you are located, but I can put an engine package together for you, even build you an LS7 that would be perfectly reliable. If you were going to ditch the dry sump setup you might as well build a new engine by the time to resource the parts necessary to do it.
As someone mentioned you need to change the reluctor on the crank as well. Timing set, front cover, the list goes on and on. I can do it for you if you have your heart set on it, but I am sure I could build you an engine and install it for what you are going to spend on just the crate motor and retrofit with a dry sump.
Thread Starter
Former Vendor
Joined: Oct 2006
Posts: 7,331
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From: Port Huron MI
Can you put an ls7 top end on an ls3? I know you can stroke an ls3 out to 427, wondering how that would do with an ls7 top end and baby cam? Obviously not GM reliability, but it probably wouldn't be strained too much not going too aggressive. Probably a dry sump and larger radiator would be in order as well?
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Le Mans Master
Joined: Feb 2002
Posts: 5,970
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From: San Marcos Texas
Can you put an ls7 top end on an ls3? I know you can stroke an ls3 out to 427, wondering how that would do with an ls7 top end and baby cam? Obviously not GM reliability, but it probably wouldn't be strained too much not going too aggressive. Probably a dry sump and larger radiator would be in order as well?
BUT!!! ETP heads makes an LS7 head for small bore engines that bolt right up to LS2/Ls3 motors..
Premium Supporting Vendor
Joined: Mar 2001
Posts: 5,241
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From: Knoxville Tennessee
Can you put an ls7 top end on an ls3? I know you can stroke an ls3 out to 427, wondering how that would do with an ls7 top end and baby cam? Obviously not GM reliability, but it probably wouldn't be strained too much not going too aggressive. Probably a dry sump and larger radiator would be in order as well?
We could put an LS7 together for you. The heads are going to cost you more than a good set of LS3 heads, but I think the overall cost would be marginal.
You cannot put LS7 heads on an LS3 block, the 4.070 bore is too small, needs to have 4.125 IMO.
I will tell you, I am not sure why everyone thinks that a factory engine would be more reliable than one that I build? I use top quality parts and especially with an NA setup, you should have NO issues for years with a proper tune and good maintenance.
Again, I would skip the dry sump for what you are going to do.
Here are two of the pictures that of how I did mine.. I am happy to replicate the setup for you, it is just not cheap to do.
Thread Starter
Former Vendor
Joined: Oct 2006
Posts: 7,331
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From: Port Huron MI
looks great, if a dry sump is not necessary, then I don't see the need to drop all the cash on one. Fire me over some prices for a stroked ls3 and a basic ls7 whenever you get a chance. Everything that would be needed to drop into my C5
Burning Brakes
Joined: Apr 2009
Posts: 946
Likes: 2
I agree with Nick -- a gm engine is no more reliable than any other engine assembled with the same specs and clearances. In some cases, you can better that reliability during your one-off build.
Most of your long-term reliability will come from the tune (assuming a skilled engine builder checked tolerances and assembled the engine with care). Save some of that LS7 money for a great tune from a reputable tuner, have the engine professionally assembled, use quality parts, stay sane (e.g. don't max out every thing as you might in an all-out effort build) and you'll have a very reliable engine no matter what base you start from.
Most of your long-term reliability will come from the tune (assuming a skilled engine builder checked tolerances and assembled the engine with care). Save some of that LS7 money for a great tune from a reputable tuner, have the engine professionally assembled, use quality parts, stay sane (e.g. don't max out every thing as you might in an all-out effort build) and you'll have a very reliable engine no matter what base you start from.
Premium Supporting Vendor
Joined: Mar 2001
Posts: 5,241
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From: Knoxville Tennessee
Let me know where you are located too.
