Jade Mills

I had always planned to swap a ls3 into my 82 Vette, as I already have an ls1 in there so it would be incredibly easy, but the past few days I have thought “stuff it, up just max out the ls1, that should get me fast enough”.
how much power am I missing out on, I have ordered a few things like a fast intake with throttle body, underdrive pulley, 243 cnc’d heads and a few other little things for my cammed ls1, so let’s say I have those on mine, with long tubes, gm asa cam, how much power difference is there if I put all that into an ls3?

If the ls3 is, say, 20% more powerful than the ls1 in stock form, will it be around 20% with the exact same mods? Or more Because of larger displacement? Or less because the heads flow pretty well, cam is more aggressive (per cubic inch), intake more efficient, etc

Basically I am weighing up if I should stop modding the ls1 because potentially I’ll mod the ls3, would that extra few thousand $$$ (including the sale of my previous ls1) is worth the gains?

anyone upgraded before and done similar mods to their previous LS?

HCI2000SS

iTrader: (2)

Basically if you put the same exact top end on a larger cube motor you'll make about the same peak power as the smaller one, but with a bit more torque.

Darth_V8r

iTrader: (4)

A tale of two bolt on cars. A 2002z06 and a 2012 1LE. Both I believe set bolt in records. Same basic recipes.

1-7/8 headers, x pipe, meziere wp, light clutch, high ratio rockers, tensioner delete, fast102 intake on the Z and modded ls3 intake on the 1LE, 102tb on the Z and ported stock TB on the 1LE. Both cars stock heads and cam. And I mean untouched heads and cam. And of course tooning. Both 6 speeds.

Z made 441/386 or very close to that.
1LE made 478/470 or very close to that.

To my knowledge, both hold the bolt on records for their prospective platforms. I don't know the track numbers on the Z but the 1LE ran 11.5x at 121.x. Not 100% on the trap speed. But that's about as good a comparison as I think you'll find.

Does that help?

99 Black Bird T/A

iTrader: (4)

Sounds like a fun project for the 82 vette regardless if I've choice is LS1 or LS3.

My 72 vette has a Dart 400 with a big fat flat torque curve but only makes bolt on LS1 horsepower. The car is an automatic and the low rpm torque is a lot of fun with every day driving. My 91 RS & 99 TA make way more hp but feel "peaky" compared to the Dart 400.

If ~ 400-425 rear wheel hp & 375-400 torque are enough the LS1 with intake ported heads and cam should get in the ball park. The drive line on the 86-82 Corvette tends to eat up more power than the new cars in my experience. If 450+ hp & tq is the goal the LS3 is a better starting point.

My vette is 3180 pounds with a full take of gas on calibrated scales. The 346 rear rear hp feels faster than the TA's 418 rear wheel hp due to the Vette's lower weight and fatter torque curve. The 72 vette pulls the my TA on the roll when we've ran them. Then at ~100+ the TA starts reeling in the vette. With fat torque curve the 72 vette has hurt the feelings of a lot of newer but stock or near stock LS1 Vette's on the street over the years.

Best of luck with the project.

BTW is used to want to swap an LS into the vette but am happy with the Dart 400.

Jade Mills

Yeah I have decided to make the most of the ls1 as opposed to upgrading unless I see a real bargain for a crate ls3,

i have done ALOT of weight loss mods for my c3. I’m at 2900lbs with full tank. So I am doing 0-60 in 3.6 with no wheelspin at all with my 2.87 rear end and stock verter, So I finish the quarter mile in 2nd still.

ready to install I have already bought a 3200 9” stall, fast 90 intake, fast tb and looking at aftermarket heads to port (or 243’s). So I still have a little bit to go for good numbers

i think if I could get a lighter car like mine to say 420hp, then I wouldn’t notice too much of a difference to 450ish hp of an ls3 with similar mods (as they will both be stupid stupid fast)

i will I’ll do a new write up of the mods I install and have installed. As I have a gtech (I know, it’s not as accurate as the stip, but it is a good indicator) and I have a 1mile stretch of private road on my property, so I gtech the quarter miles sometimes 10 times a day and average it out, (with no wheel spin and dead hooking on the street the et results never vary more than 0.05, so I’d say that’s pretty accurate.

VandykeT/A

Most of the cam only LS3 cars I've seen made in the 475-480 range and were very streetable considering they're mostly gonna be tuned MAF only. It takes a well put together Heads cam intake set up to make those numbers with a LS1. The LS3 would be a more driver friendly set up making big power. Basically your gonna need a well built LS1 to make cammed LS3 numbers and the LS3 will have more power in the lower rpm. Would I pull a perfectly working LS1 to swap a 3 probably not. I would just work with the 1 and if it blows and you decide to swap you could sell the cathedral stuff and not lose a lot.

G Atsma

Here is where displacement and BIG OEM intake ports have the edge for overall power.

Cahill93Z28

For the cost you already have in your modded LS1, I don't think it would be worth it, unless you got a steal on an LS3. But it depends what your goals with the car are.

Not-The-Johnny

Holy Crap 2.87 Gears... Put a Set of 3.73 Gears and 3200 RPM Converter in the thing, and you won't need an LS3....

Jade Mills

Ha, yeah, I really enjoy them. Awesome fuel economy is a bonus (but that’s beside the point with the Vette) but it means I launch every time with no wheel spin on the street, making me much faster on the street than nearly everyone, even if I pull up next to a Ferrari or a massively modded ls7 there is a good chance I’ll be up on them due to dead hooking on any surface. And I read that a stall will pick up 80% of the slack of the gears, apparently only worth .1 or .2 in the quarter if you have already put in a stall.

Tbh a 2.73 might be more beneficial to my times than 2.87, as my 0-60mph would be reduced (due to gears would shift at 65ish) and I would spend the quarter mile in 1st and 2nd without changing to 3rd (like I do the last second of my 1/4 runs)

i know a lot of guys say how good their rear ratio is without trying the higher gears, and most that upgrade say they should have done it sooner, but I think high 11’s on a mild cam with stock verter and 2.87’s on the worst roads imaginable is pretty alright for my needs

big hammer

Ls3 can make 500 rwhp cam only relatively easily while it takes a pretty max effort ls1 to do that

wannafbody

iTrader: (2)

I'd do Mamo heads, Fast intake on the LS1. Cost less than the LS3 and probably more fun on the street with better port velocity at lower rpm.

LS3 for an all out max track build.