LS3 Engine Decision----which one?

[Vega$69]

Originally Posted by 1965_SS

You still need to tune those GM crate motors even if you use the GM harness, right?

Video would be awesome!

I like a lopey idle...........I had a big block with a Comp Cam [email protected], that was pretty radical.

The GM Performance Harness in both the 480 and 525 are plug and play. No tuning was needed on either one.

[gnx7]

Remember that HP is a measurement of torque over time.... so the LS7 would kick it in the nuts due to that alone (more torque). Add cam/headers to an LS7 and it will make 600hp+ with perfect driveability.

[Vega$69]

Originally Posted by gnx7

Remember that HP is a measurement of torque over time.... so the LS7 would kick it in the nuts due to that alone (more torque). Add cam/headers to an LS7 and it will make 600hp+ with perfect driveability.

The LS3 525 beats the stock LS7 across the board. Better HP and Torque

My 69 with the LS3/525 pulls my Corvette ZO6

Change the cam in the LS7 and 620-650 hp and 550 torque are easy #s to achieve and still very street friendly.

My last 69 I used an LS7 with a Texas Speed cam and ran 505 rear wheel at only 6200. Car was a beast. However my LS3/525 is also killer setup.

I just bought another LS7 for my kids build. Of course will do a cam change and convert to wet sump. Funny part is that just yesterday we started talking about selling the LS7 and buying a LS3/525. The money saved would pay for a lot of other stuff.

[markaaron80]

id go 430hp and contact Brian Tooley and pick a cam from the Hot Rod mag issue. picked up over 80hp from the 480hp crate engine with just a cam swap. ended up with 575hp max but very tight piston to valve .003
http://www.superchevy.com/how-to/eng...ick-boomerang/

[Tom.A]

I went with the 430HP LS3. Got the car running and then did a cam swap.
HP exceeds the 295/35/18 tires very easy. However the cam swap that I used does make car buck some what at low speeds but it is not a big issue and still does fine in traffic. It is 227/237 , 613/622 with 114 Lobe centers. Dyno numbers are very subjective but my car was 517HP / 497 TQ at the wheels through a 9" with 3.55 rear and a TKO600 with no other mods other than long tube headers. I feel it was a very generous day. Either way these LS engines are sneaky fast and start every time. They don't put out the same thump as a SBC can or BB does but way less drama on top of decent fuel mileage

[Vega$69]

Originally Posted by markaaron80

id go 430hp and contact Brian Tooley and pick a cam from the Hot Rod mag issue. picked up over 80hp from the 480hp crate engine with just a cam swap. ended up with 575hp max but very tight piston to valve .003

430 and a call to BT will get you 550 with good driveablity and you'll save a few bucks over the 525 if you do the swap yourself. Adding the cost of tuning may wipe out and savings.

Downside is you lose the warranty.

[awr68]

All great info guys! I love real world experience! I'm wanting to change to a LS soon and this helps a lot!

[MOREHORSEPOWER]

I would just buy the 525!

1 If I buy a new crate engine I would keep the WARRANTY !!

2 HP cost money ! I may be wrong but how to you gain 45 hp with just a cam swap alone in this engine ? If it started with the same platform as the 430 hp engine that is a gain of 95 hp .

3 When i was younger I was told a HP would cost $100 per HP . Today's money would more like $400 per HP.

[Vega$69]

The 430 is a smog motor. To meet epa standards the exhaust side gets choked down among other things

Swap cams and badabing you get big power and great drivability.

[randy]

i went with the 480hp version. Should fire up within 2 weeks. Might be next week. I wanted a little extra kick now and then in the future i will upgrade it. Nice learning curve and then tweaking everything else