I know of a man locally (here in Ny, not michigan) running a 9.9x with STOCK bottom end, LS1 Castings, gears, stall, 200 shot. Suspension too . sounds damn tame too. Then it ate a viper like it was nothing


Ls1 also has some other improvements like the lighter all alum block, "better" firing order, better combustion chamber design amongst other things.

 

I'm not an LS1 guy, much to my dismay but I have never seen the above to be true EXCEPT on home ported heads which may well have been worse than stock. Cars pull 390+ RWHP with stock heads and small cams, that isn't exactly like an LT1, with or without LT4 heads.

 

Even if the stock internals could take it, I haven't seen it been done "yet."

Most solid roller stroker LT1s are seeing 450-470ish RWHP, not stock bottom cars like LS1s, who FWIW are missing 2 cubes vs an LT1 I think we are dreaming if we want to believe the LT1 isn't at a disadvantage, not saying its crap, who "needs" 600 HP anyway, but... I think the LS is king and I think it is very, very obvious. The reports of reliability problems with "high" miles though does not make me feel warm and fuzzy.

 

Well, peak torque of the LS1 stock is about 4400 RPM I believe, thats almost like an import 6 banger. Maybe a bad comparison, but it says something to me, whatever that something is it makes it appear peaky.

Linky no worky

 

This is one thing I looked at too, although more in line with lifters. Less lobe lift, more rocker, so lifter float should be less an issue if nothing else and probably allows for steeper ramps(?)

 

The torque peak isnt table top flat like an LT1, its defintely peakier... but that peak is hihger than any LT1 ive seen

my Stock LT1 (97) dynoed 267/312, and my grandmothers stock 02 dynoed 325/350. They have a big fat midle, and the power is up in the power band where it sees on acceleration. These cars never drop beleow 400 rpm when racing.

 

I hope the engine doesnt drop below 400 rpm when racing let alone idling.

 

Go look at the Cam. Look at the base circle size vs the lift, and the cam journal. You'll find out one more reason why this is possible. If you've ever seen a Cam lobe master, you'll get this imediately.

The point you made thou is very true. Still a AFR hydr rev kit would help.

Bret

 

I have a Corvette FI manual, and it has an interesting chart of the stock HP and torque curves for the L98, LT1 and LS1 (Corvette versions) plotted on the same chart. In all cases, the LS1 makes equal or more torque than the LT1. At lower RPM, the curves for the LS1 and LT1 are almost identical, but as RPM comes up, the LS1 torque starts to take off and leave the LT1 in the dust. Its a tiny chart, and hard to read numbers with any accuracy, but I think it demonstrates that the LS1 isn't a slacker on the low end, its just an over-achiever on the high end.... .

Buddy of mine with a 125-shot on a stock LS1 bottom end, stock LS1 heads, ZO6 intake, cam, headers is running almost the same MPH that I am with a 381 LT1, decent LT4 heads/intake and a 125-shot....... I've got him by nearly 10% more displacement and several kilo$$$ investment, and he is still running almost the same MPH..... I'm impressed.

 

DAMMIT!! I guess it's time to get rid of the 96 SS and get a 98 or newer.

 

I thought that too. I would think that the LS1's low end is made up by compression and head flow.

It's the LS1's heads and the extra lift make all tha HP. Funny how you get 350HP from a LS1 and 280hp from a LT1.

Bret

 

Even without the heads, the firing order is worth a small advantage, in exaust pulsation 'tuning.' Plus again with the heads, with removing the siamesed exaust ports from the center cylinders will help reliability in a race situation, keeping the center cylinders cooler and thusly have the ability to run some more timing/power, and less likely to blow a gasket.

Then how about the individual coil packs, better for high RPM stuff, although I dont believe the LS1 PCM has individual cylinder timing control (I dont think so, but dont know for sure), shoot its still a better engine. Internals just cost some duckets, and I wonder about these "reliability" issues people talk about. The only thing I'm aware of is a top ring flutter/oil consumption issue which was fixed in Y2K I think.

 

how about Chris Sikora Z28 or Goerge Baxsters Z28? aren't they LT1's? over 144 to 155 mph in the 1/4. i know they are blown but i think they are heavy and there is no wieght reduction at all as so many LS1's. in the end i know LS1/LS6/6.0L/5.3L heads are better than LT1/LT4 heads and they do make more power than LT1's.

 

But there is a "power adder" LS1 in the 8's!!!

Madman has run 8's with his former LT1 car, but that's with a Gen 1 aftermarket block.

It will be interesting to see how they manage to keep the LS1 heads on the block, with the reduced number of head bolts compared to the Gen 1 and LT1 heads.

 

Fred, i'm not interested in NOS'd LS1's that run 8's acutaly i will be interested in LS1's and LT1's that are NA, supercharged or turbocharged that can run 9's or 8's or quicker. for the MadMan LT1 that ran 8's wasn't that Z running LT1 or LT4 style heads and not SBC heads regardless of using gen 1 block