which LS3 to go with?

[class67]

I am new to the LS swap and am wondering if it's better to buy the 430hp version and change the cam, springs etc.. for more power? or do I just buy the 525hp version and be done with it? which is more cost effective? what should I know?

I appreciate any advise or thoughts this...

[sd67]

My opinion on this is that you shouldn't buy a crate motor and then open it up and modify it. Go with either the 480 or 525 and be done with it. If you are going to modify a motor, pick up an LS2 put the cam in it and new heads. I personally don't have the skills to build a motor myself and don't have an engine builder that I trust, so I felt better with a create motor.

[JKnight]

I think there's some merit to the logic in the statement above. That said, it's an intriguing question that I'm curious about as well. Seems like it would make sense to drive a 480hp version for a few years (use up the warranty) and see what you think. If the flat torque curve of that LS engine isn't enough as it comes from GMPP, tweak it later and there's really no significant money lost.

By significant I mean that you're spending 11k+ on an LS swap, what's another $800 2 years later if you decide you gotta have another 40-60hp. These cars are never really done right?

[Z06vette]

I can def understand not wanting to tear into a new motor. Buying the 430 and swapping the cam & springs is the best bang for the buck. And the power difference is significant. In most situations you'll have to change the oil pan anyway. Its a much easier and cleaner job to change the cam & springs while the motor is out... Really only need to pull the balancer, timing cover, cam sprocket, rockers & valve springs. If you'd have to pay someone to do this, the crate 525 is best choice. There is the issue with tuning, however. The crate motors come ready to go if you buy the ecm & harness. Everyone's situation is going to be different. I was just about to buy a 430 crate, and I decided to look around for some low mileage pullouts from reputable places. I found one complete with harness, computer, accessories, all sensors, etc. I sold everything I didnt use, sent the heads to texas speed to be cnc'd, and bought one of their cam kits. It worked out well, and I enjoy doing the work. I have a good local tuner which also helps. Scott

[jwcarguy]

Steve,

It is best to describe your "comfort level" in your skills and/ or acess to people with skills to do any engine work, etc

I always tell people to ask themselves, what are your goals and driving expectations with the car, as well as budget?

Those two things, basically answer your question

If you are limited on skills, tools or people to do the added work, stick with a crate engine option
Or look into the many builders that can build you a engine to fit your needs
you can choose between Gen III or Gen IV setups and pcm's (effects some harness/ pcm, tuning prices)
examples (not promoting, just a fyi)
http://www.thompsonmotorsports.net/product_info.php?cPath=23_31_33_439_487_492&products_id=206
http://www.thompsonmotorsports.net/product_info.php?cPath=23_31_33_439_487_492&products_id=207


As mentioned earlier, if the new engine warranty is a main factor, then cracking the engine open to install a larger cam is of the table, due to voiding the warranty
Also, look into if even swapping the crate engine oil pan, effects warranty??
Not sure on that

Also, check with some tuners and find out how adaptable the GMPP pcm/ harness setup is to engine mods?
some earlier versions were only good for the GM configuration

Plus, there are so many other aftermarket companies selling the pcm & harnesses (some cheaper than GMPP setup) and can get up up and running with a "base/ mail order" tune, then either dyno tune or remotely with a setup like EFI Live Autocal, etc

Hope this helps
Jeff

[gnx7]

If you look on Corvetteforum you can often find LS7 pullouts for about the same price as a crate LS3. The main issue with the engines is the valve guides can wear prematurely from the factory so the heads should have either had that done... or will need it done. 20% more cubic inches does wonders for power output.... namely torque.

The oiling system can be converted to wetsump via a spacer and different oil pump/pan. Add a bigger cam and MSD Atomic intake/headers/tune and gains of 100rwhp+ are achievable.

That being said I'm ordering a crate 430hp LS3 for a customer as he wants a warranty and gets used to the car.... before going nuts on it :G-Dub:

[class67]

Thanks for all the thoughts and advise. food for thought for sure, I'm not really afraid to work on the motor or to worried about the warranty either. Just wondering if it was really worth it to start with the lesser hp motor and upgrade it. I'm leaning towards just going with 525hp motor and be done with it, most likely.

[randy]

I went with the 480hp version. More than enough power, warranty, great cam sound, and sounds mean as hell.

[class67]

I went with the 480hp version. More than enough power, warranty, great cam sound, and sounds mean as hell.

That's what I like to hear :thumbsup:

[71RS/SS396]

The 525 is a good engine that has a cam that will be easy on the valvetrain. Keep in mind you'll pay $1,400 dollars for a cam and valve springs buying the 525 vs the 430, unless you don't want to mess with changing the cam.

[kwhizz]

A friend put a 525 engine in his car and doesn't like the driveability of the combo.......we just put a 480 version in Gary's car and it is freak'in "Awsum".....Just my $.02

Ken

[fishface]

I'm different from most here. I went with the stock 430 up version. My car is 100% street and my thinking that with headers, CAI, and a tune it will be a blast to drive and more than enough power for cruising.

[Schwartz Perf]

We put cams in LS3 430hp crates quite often. I can get you a better driving combo that'll have the same hp as the 525 for the same price. However, it won't have GM's warranty anymore once you open it up.

I agree with Kwhizz's friend, I don't like the 525 driveability, but many people have no problem. Guess it's all about what you're used to.

-Dale

[class67]

A friend put a 525 engine in his car and doesn't like the driveability of the combo.......we just put a 480 version in Gary's car and it is freak'in "Awsum".....Just my $.02

Ken


I'm curious, what are the drivability complaints?

[Yelcamino]

A friend put a 525 engine in his car and doesn't like the driveability of the combo.......we just put a 480 version in Gary's car and it is freak'in "Awsum".....Just my $.02

Ken

I heard the same thing from a few people. I opted to get the 430 and swap out the cam, pushrods, timing set, timing chain tensioner to a LS2 style (I was told the LS3 version was an issue), trunnion upgrade, valve springs, retainers, and locks.

Now it has a nice hot rod sounding idle and made decent power to the wheels (454hp/412tq) when I got it tuned.

[class67]

I heard the same thing from a few people. I opted to get the 430 and swap out the cam, pushrods, timing set, timing chain tensioner to a LS2 style (I was told the LS3 version was an issue), trunnion upgrade, valve springs, retainers, and locks.

Now it has a nice hot rod sounding idle and made decent power to the wheels (454hp/412tq) when I got it tuned.

Thanks for chiming in, Herb
I think I've changed my mind on the 525hp version, going off of what I've heard from all of you recently. You have a custom ground cam, right?

[Yelcamino]

Thanks for chiming in, Herb
I think I've changed my mind on the 525hp version, going off of what I've heard from all of you recently. You have a custom ground cam, right?

Yes it's a custom grind. I'm sure there are plenty of off the shelf cams to choose from that are proven and will make good drivable power. :thumbsup:

[Johnny@Speartech]

The LS376/480 crate engine is a really good option. The 525 we have heard issues with driveability as well. The 480 is what we put in our 240SX shop project and we love it. I'd recommend that.

https://www.speartech.com/ProductDetails.asp?ProductCode=speartech240lsx

[1965_SS]

I'm curious, what are the drivability complaints?

X2, curious as well.

[abadsvt]

I'm not a motor guy but why is the 525hp crate ls3 causing people to complain about it? I just ordered a 515hp ls3 crate from smc performance and am a little concerned now. I plan on driving my car every where so drivability is important to me. Thx.

Josh

[dhutton]

I'm not a motor guy but why is the 525hp crate ls3 causing people to complain about it? I just ordered a 515hp ls3 crate from smc performance and am a little concerned now. I plan on driving my car every where so drivability is important to me. Thx.

Josh

Weak low end torque and surging as far as I know. Some guys love them.

Don

[abadsvt]

Weak low end torque and surging as far as I know. Some guys love them.

Don

Gotcha. I hope that isn't the case with mine. I guess time will tell. Thanks

Josh

[cjsgarage]

Hey Josh, I was just in Atascadero this weekend picking up an LS1. I used to live down there for a long time. I'll be back a couple more times this month and next.

Also.. something to think about: The aftermarket cams will need periodic review of the valve springs if you go over a certain lift. The 525 has some sacrifices in order to achieve a higher HP number, but it's under warranty, and theoretically won't need valve springs to be changed.

Texas Speed has a cam that adds 104 HP to an otherwise factory LS3, but it's going to be rough on valve springs (which might not be ideal for a daily driver car) and requires tuning.

The headers and intakes most people put on the engines also helps a bit with power output. Tuning makes the most of these also.

[jwcarguy]

Hey Josh, I was just in Atascadero this weekend picking up an LS1. I used to live down there for a long time. I'll be back a couple more times this month and next.

Also.. something to think about: The aftermarket cams will need periodic review of the valve springs if you go over a certain lift. The 525 has some sacrifices in order to achieve a higher HP number, but it's under warranty, and theoretically won't need valve springs to be changed.

Texas Speed has a cam that adds 104 HP to an otherwise factory LS3, but it's going to be rough on valve springs (which might not be ideal for a daily driver car) and requires tuning.

The headers and intakes most people put on the engines also helps a bit with power output. Tuning makes the most of these also.


"Texas Speed has a cam that adds 104 HP to an otherwise factory LS3"
Where is that listed??

[Vega$69]

"Texas Speed has a cam that adds 104 HP to an otherwise factory LS3"
Where is that listed??

X2. Where is that TS cam?

The GM Hot Cam (525) is 95 HP over the stock 430 LS3. I liked the way it sounded and the performance was great. No surging or any other issues.

So where to you get the "sacrifice" on the GM 525 crate motor?

Torque at over 400#s at 3000 rpm and almost 500#s at 4500 rpm

BFG Rival S 335/18s with 3.70 gears and a T56 Magnum would spin the tires all the way deep into 3rd

[abadsvt]

Hey Josh, I was just in Atascadero this weekend picking up an LS1. I used to live down there for a long time. I'll be back a couple more times this month and next.

Also.. something to think about: The aftermarket cams will need periodic review of the valve springs if you go over a certain lift. The 525 has some sacrifices in order to achieve a higher HP number, but it's under warranty, and theoretically won't need valve springs to be changed.

Texas Speed has a cam that adds 104 HP to an otherwise factory LS3, but it's going to be rough on valve springs (which might not be ideal for a daily driver car) and requires tuning.

The headers and intakes most people put on the engines also helps a bit with power output. Tuning makes the most of these also.

Thats crazy. What a small world!!! I live in paso robles but my shop is in atascadero. Wow 104hp is a huge increase. I'll keep that in mind if I need more hp! Thx

[dhutton]

X2. Where is that TS cam?

The GM Hot Cam (525) is 95 HP over the stock 430 LS3. I liked the way it sounded and the performance was great. No surging or any other issues.

So where to you get the "sacrifice" on the GM 525 crate motor?

Torque at over 400#s at 3000 rpm and almost 500#s at 4500 rpm

BFG Rival S 335/18s with 3.70 gears and a T56 Magnum would spin the tires all the way deep into 3rd

I think the Hot Cam is in the 480 hp. The 525 hp version uses the ASA cam. Interesting thing is the 480 hp version has more torque and hp up to 4500 rpm in the curves I saw. Depending on how you drive the 480 hp MAY be a better choice.

Don

[abadsvt]

I was just looking to compare my motor to the 525hp ls3 crate. I ordered mine from SMC Performance and here are the specs they list. Its a 515hp ls3 crate. I didn't see many specs online for the 525 besides saying it has the ASA camshaft.

Engine Build Specs. Upgrades marked in red

10:7 to 1 static compression
New GM LS3 Aluminum Block
New GM LS3 Aluminum Heads, Dual Patriot Performance valve springs with titanium retainers
GM flat top pistons, with GM ring pack
New GM Performance coated main and rod bearings
New GM LS3 rods with ARP rod bolts
New GM LS3 nodular iron crankshaft (58X)
New GM high volume oil pump
New GM LS3 1.7 rocker arms
New custom ground Competition Cams camshaft. SMC Stage 2 with good idle and driveability
New GM LS7 hydraulic roller lifter
GM head bolts
5/16" Chromoly push rods
New GM LS3 C6 Corvette wet sump oil pan
New GM intake manifold assembly 42 LB. injectors
New GM LS3 Ignition coils and wires
New GM gaskets and seals

Are most of these upgrades the same as the 525hp build? Im not a motor guy and went with this setup from talking with SMC. Thanks

[Vega$69]

I think the Hot Cam is in the 480 hp. The 525 hp version uses the ASA cam. Interesting thing is the 480 hp version has more torque and hp up to 4500 rpm in the curves I saw. Depending on how you drive the 480 hp MAY be a better choice.

Don

Yes you are correct on the cams

Here are the dyno sheets for both comparison. The torque for the 525 is higher across the curve

I also installed a 480 in a friends 69 and he loves it. If you look at the dyno sheets it appears the 480 dynoed closer to 500 hp at 6000 rpm and I believe I'm now seeing it marketed as Chevrolet Performance LS376/480 LS3 6.2L 495HP Engine

http://www.jegs.com/i/Chevrolet-Performance/809/19301358/10002/-1

[dhutton]

Yes you are correct on the cams

Here are the dyno sheets for both comparison. The torque for the 525 is higher across the curve

I also installed a 480 in a friends 69 and he loves it. If you look at the dyno sheets it appears the 480 dynoed closer to 500 hp at 6000 rpm and I believe I'm now seeing it marketed as Chevrolet Performance LS376/480 LS3 6.2L 495HP Engine

http://www.jegs.com/i/Chevrolet-Performance/809/19301358/10002/-1

Different curves with different result here:

http://www.pro-touring.com/threads/113156-Choosing-the-right-LS3-crate

I'm going to guess the 480 produces more torque down at 2000 rpm....

Don

[Vega$69]

Different curves with different result here:

http://www.pro-touring.com/threads/113156-Choosing-the-right-LS3-crate

I'm going to guess the 480 produces more torque down at 2000 rpm....

Don

maybe so at the lower rpm.

I see guys suggesting the 430 and cam swaps.

If you swap the cam you'll have to custom tune which will add to the cost.

Secondly and more important IMO is you will lose the warranty on the engine. For some that's not a big deal. However if you have any thoughts of selling the car having the GM Performance warranty is nice to have.

My buddy is extremely happy with the 480 I put in his car almost 3 years ago. Never an issue.

I really like the 525 for the extra $1000. For me it's was perfect and I would go that way again. It drove perfect and the sound is different then the 480.

That said you can't go wrong with any of the LS3 crate motors.

[randy]

don't mind the slight belt squeak.

Here is a video from tonight testing out the car. I still need to fine tune the car but for now the car runs great with the supplied tune.

https://www.facebook.com/photo.php?v=10100926957546926

[cjsgarage]

apparently Texas Speed has redone their website. The former version of the site listed their stage 4 as having gained 104 hp.

I also noticed their cams are now ground in house. I personally have stopped shopping from them. Their house crank went out of spec in less than 30 seconds of partial low oil pressure due to poor hardening process and their house rods were out of of round even when they supplied the ARP hardware installed.

[cjsgarage]

don't mind the slight belt squeak.

Here is a video from tonight testing out the car. I still need to fine tune the car but for now the car runs great with the supplied tune.

https://www.facebook.com/photo.php?v=10100926957546926

your caption for the video says you don't think the rpm gauge is working. The LS puts out a 4 cyl pulse. Not sure if you're alreayd over that hump. But I thought it might help