[Formulajones]

If 600 streetable HP is all you're after, back when I was fooling with this stuff, the popular thing to do was grab the iron 4" bore block and stick a 4" crank in it.
Usually .030 over making a 408. Bunch of those were running around before the after market LSX block really took hold. At that time the aftermarket was scrambling to produce CNC heads and there were a few good ones that hit the market.

Had a few buddies that ran 408's in their 4th gen camaros, with mild gears, and either an auto or 6 speed. They would run 10.60's or so at 125-128 mph and they were very mild street cars. Certainly not 7000 rpm screamers.

I don't remember what the engines dyno'd at but they were well over the 600 mark to move a 35-3600 lbs. street car that fast. Just a nice set of cathedral port heads (The square ports weren't around yet) and a mild hydraulic roller cam. Most used the stock LS6 intake too unless you had the coin for the LSX intake, but again that was fairly new stuff when I started playing with them.

I ran primarily LS1's and had one 6.0 (LQ4) and one LS6. As far as torque goes, that's all relative. Certainly the LS1's weren't comparable to the DZ 302. As a DZ 302 owner and having owned many LS1's I can say with certainty the LS1 wasn't all that bad down low, and even the little DZ does well for what it is, the LS1 just does it better. But a 4" crank in an LS will certainly improve in that department as I would think that would provide enough torque to satisfy if that's what you're after.

For me, the LS1 with a cam and some bolt ons were enough to satisfy my fun factor in our daily drivers. And it was cheap fun. I liked 3.73's with the 6 speed, 28 mpg and on street tires spinning I could dip into the 12's at 114 mph, only had a 224 @ .050 cam in it LOL. Probably dip into the low 12's or high 11's with a good tire based on the mph. It weighed 3620 without me in it. For a 346 they are still impressive. My wife drove that to work daily for years.

[cdoggy81]

Having owned both & gone down this path you can make anything work if you throw enough $$$ at it That being said it is easy & cheap to do it with a LS & you don’t need a lot of displacement. This is why I don’t think you see a lot of over 500 CID LS.
I went down this path for my last build. I wanted ~600hp at the crank (500hp at the tires basically) & fuel injection. What it was going to cost me to get to that going all Pontiac was more than I wanted to spend. Enter the LS solution...
I took a 48k mile bone stock LS3 ( that’s 6.2L or 376 cid for the non LS guys), had the heads ported, put in a mild cam (225/232-.595”/.610”-112LSA), a set of 1 7/8” headers with 2.5” exhaust & hit those numbers. MPG is close to 20 with a 3.42 rear & a 26” tire. Even with a 295 width & 220 traction rating tire I can’t floor it when taking off as it shreds the tires. Those who say LS have no TQ clearly have never driven in a built one. If this engine ever goes south on me my next step up would be a 408 stroker. From there a LSX454 but I’ll just tell everyone it is a 455 😎

[Scarebird]

Originally Posted by cdoggy81

..If this engine ever goes south on me my next step up would be a 408 stroker. From there a LSX454 but I’ll just tell everyone it is a 455 😎

You may want to examine the LT architecture. Direct injection does some really nice things efficiency and power-wise.

https://www.motortrend.com/features/5-3l-l83-dyno-test

[Formulajones]

Originally Posted by cdoggy81

Those who say LS have no TQ clearly have never driven in a built one. 😎

Agree. Even a stockish one isn't bad.

As an example of a really broad power band with plenty of torque, here is my stock LQ4 6.0. Even had the stock truck manifolds on it. Engine was never cracked open. All I did was give it a custom tune. Put it in this Blazer that weighs 5300 lbs. without me in it. Stuck 3.73 gears in it which honestly wasn't enough with the 33" tires, if you listen I'm just getting into 3rd gear at the finish line, nearly finished in second gear, which is a 1.62 in the 4L60E I'm using in it.

Yet it still made enough grunt to push the truck to 14.30's at 95-96 mph, and was enough to embarrass that brand new 2010 SS camaro at the time. And that was a soft leave because it had a habit of snapping the pinion clean off the 12 bolt truck rear, and I needed to drive it back home 110 miles. Yeah it makes decent grunt

https://youtu.be/msgSc3S-yHA

[62posbonny]

Yeah. I personally have a 370" LQ9 with AI ported cathedral heads, cam motion 227/232 cam, 1 7/8" headers, truck intake, stock truck TB, built 4l65e trans, 2600 stall converter, 3.73 gears in my 71 Cutlass. From a standing start it burns the Nitto 285/35r18 555G2's to 80mph before gettting traction. I haven't gotten dyno numbers with the latest tune, but it made 400tq and 405hp at the wheels with my old tune, and my new tune feels like a whole new car. That car is snappy and will prove to a lot of LS haters that torque is not lacking.

I love and will never swap out my 63 Catalina 462, but there is nowhere in the power band that it feels even close to as quick as the Cutlasss. Maybe after some forged rods and the ported 96's that flow 250@ .500 and a little more cam it might be a good fight. The cars are built for different purposes though, with the Cutlass being tasteful resto-mod and the Catalina more nostalgia street racer. I am of the belief that there are a lot of ways to have fun, and all options should be explored.

[Scott Roberts]

Back to the big ci ls engines Paul is "asking" about..
No need to go big on an LS. They weren't designed to be big ci engines. Like it or not, it's a better design than the Pontiac. Guys are running 3.70's on 440ci at 2550lbs... what was Tommy Y when he ran at a 3.90 ( best he got) and 505ci?

L

[Stan Weiss]

Originally Posted by Scott Roberts

Back to the big ci ls engines Paul is "asking" about..
No need to go big on an LS. They weren't designed to be big ci engines. Like it or not, it's a better design than the Pontiac. Guys are running 3.70's on 440ci at 2550lbs... what was Tommy Y when he ran at a 3.90 ( best he got) and 505ci?

L

2900 lbs. What size tire was the LS running?

Stan

[Scott Roberts]

Originally Posted by Stan Weiss

2900 lbs. What size tire was the LS running?

Stan

Big tire car..similar car went 5.80's at 243mph.. 1/4..also big tire car.

[Scott Roberts]

Damn...I've been gone for over a week and no one wants to address the fact a Pontiac can run 5.80's at 243 at 2550lbs on alcohol?

[Scott Roberts]

Been a month now... anyone? Like to hear the old guard admit a Pontiac can't run with the modern muscle on the street or track..
Not a Pontiac bashing session, god knows I have spent 10's of thousands on them...
Not gonna mention any names but the guy I'm after initials are Paul kinippan.. what say you?
I'm bored Paul so go easy ....

[Stan Weiss]

Scott,
OK since you have very deep pockets (which are needed for a Pontiac) tell, me why a 500 ci LS will make more power than a 500 ci Pontiac. People always bemoan the reason the Pontiac can not run with the BBC is its smaller bore spacing. Guess what. The Pontiac has a bigger bore spacing than the LS even if you go to an after market 4.5" block.

Stan

[Scott Roberts]

Originally Posted by Stan Weiss

Scott,
OK since you have very deep pockets (which are needed for a Pontiac) tell, me why a 500 ci LS will make more power than a 500 ci Pontiac. People always bemoan the reason the Pontiac can not run with the BBC is its smaller bore spacing. Guess what. The Pontiac has a bigger bore spacing than the LS even if you go to an after market 4.5" block.

Stan

I don't have deep pockets..the DirtyBird almost bankrupt me...
You tell me why a 440ci pontiac cant run 5.80's @ 240+ mph at 2550lbs... ??

[Stan Weiss]

Originally Posted by Scott Roberts

I don't have deep pockets..the DirtyBird almost bankrupt me...
You tell me why a 440ci pontiac cant run 5.80's @ 240+ mph at 2550lbs... ??

I never said it could not. As I said before it will just take a lot more money than an LS. I believe if Tommy Youmans was running big tires and had the car suspense / chassis tuning and convertor right that his 505 could have run a 5.8x.

Stan

PS Let add that is if he could get his car down to 2550#.

[Scott Roberts]

Originally Posted by Stan Weiss

I never said it could not. As I said before it will just take a lot more money than an LS. I believe if Tommy Youmans was running big tires and had the car suspense / chassis tuning and convertor right that his 505 could have run a 5.8x.

Stan

PS Let add that is if he could get his car down to 2550#.

And would that be impressive at 65ci's bigger..

[Stan Weiss]

Scott,
How many people have built very high PSI LS engine and how many people have built very high PSI Pontiac engines. Based on that ratio I would say somewhat impressed.

Stan

[krisr]

Are we talking 1000ft or 1320ft?

[Scott Roberts]

Originally Posted by krisr

Are we talking 1000ft or 1320ft?

1320...

[Scott Roberts]

Originally Posted by Stan Weiss

Scott,
How many people have built very high PSI LS engine and how many people have built very high PSI Pontiac engines. Based on that ratio I would say somewhat impressed.

Stan

Very few ls engines built at that level.. most run a proline or similar.. the LS isn't a major platform for those kind of numbers...like the Pontiac...however, it out performed the Pontiac with 65 less ci's...
I guess I'm just impressed with the LS over the Pontiac having run both..
And to ur point of deep pockets .. that's not me at all.. the DirtyBird almost bankrupt my ass.. it did get me a divorce but that was a welcomed bonus.. lol

[Scott Roberts]

So Stan, what does your computer have to say about all of that?

[Marv]

527ci is the biggest LS I've heard of, but Phonsy and his crew don't do too many - they're really a competition boat engine, though they did have one in a VF Commodore (Chevy SS) demo car for a while just to stir up some interest. We also featured that car in the magazine I write for but I can't find the feature online...

https://www.whichcar.com.au/features...-as-you-can-go