Question for the engine guru's here
 

I have been told and read countless times that the LS1 engine has less low end torque then the LT1 but a lot better high end. So in other words the LS1 will pull on LT1 from 80mph and beyond. I was told this was because the LT1 engine torque peaks at lower rpm's then LS1's.

Now I have a guy telling me that it is all wrong. That LT1's have just as good of top end pull as LS1's if you match the base RWHP. In other words If I take a 96 LT1 Z28 M6 and give it just enough bolt-ons to reach 300 RWHP and line it up with a 1999 Z28 M6 with 300 RWHP that the LT1 will stay neck and neck from 0-150. I was under the impression that the LS1 would still pull on that LT1 at 100 MPH and above and still win a 0-150 mph race.

Can anyone comment on this debate? Just trying to get the facts straight here.

Thanks

The LT1s torque peak is lower than the LS1s but I dont think the LT1 will pull on and LS1 at any part of the RPM band. No offense all you LT1 guys. Correct me if im wrong.

read what you said "give enough bolts ons to reach 300rwhp." with bolt ons the the peak power should move up in the rpm band (depending on what bolt ons). so it should pull a little more on the top end. but pull an ls1 on the top end i doubt it, what makes the ls1's top end so great is the heads. the lt1 heads are no where near the stock ls1 heads. now throw some bolt ons and heads on the lt1 then its plausible for it to walk a stock ls1.

Ok that seems logical. See his argument was the only reason a LS1 pulls a LT1 up high is the base difference in HP. So his argument is if you give the LT1 maybe headers or something that will bring it up to 290-300 rwhp to match a stock ls1 then it becomes just as fast up high as the LS1.

So if the LT1 stays with stock heads it should still get pulled a little up high by the LS1 it sounds like which is what I thought.

Anyone else wanna join in, feel free. If i'm proven wrong that's cool I just want the honest scoop here.

show him this :D, it will explain the fundimental differences between the lt1/lt4 and the ls1 and show why the ls1 is such a marvel.

its long yes but good reading. print it out for him or something.


http://www.idavette.net/hib/ls1c.html

I got pulled bad by a LT1 from the end of 3rd gear through 4th. I watch him do this to 3 other LS1's consecutively (there were 5 of us on the expressway at the same time). I hung better than they did, but still got beat. I dont know what the guy had, but he swears only CAI, and flowmaster, i say :bs: . I am glad that it happened to the other LS1's too, or i wouldve been wondering if there was something wrong with my car. Probably doesnt help with the debate, just wanted to add my .02

he definately had more then CAI, 3rd gear and 4th gear rolls for an ls1 are lethal in an m6. you should have walked him easy.

thats what i said!! i think he had some head work done or he was sprayin' cause we were pretty even through 3rd til right at the end, when he just kinda left me like i had let up on the throttle some. I was like :huh: It was a definate sleeper, looked like a run of the mill Z28, stock everything. I have since beat a few other LS1's, so i know its not me

Did you look under his hood, you should of handed him his a$$ from a 3rd gear roll. I bet he was spaying.

A friend of mine had an Lt1 with the LT4 hot cam and headers as well as many other bolt ons and dynoed just barely over 300 RWHP, or basically what a bone stock LS1 would dyno at (also ran mid to low 13s like a stock LS1 can).

Additionally, the mph is not the "top end". It's when you get above 4000 RPMS that the LS1 is great (or ~35 mph in 1st (M6 here, don't know about autos))

I have an a4 lt1 TA (just ram air and flowmaster) and a m6 ls1 TA ws6. I have never run them against each other but i can garantee my ws6 will pull away from my lt1. one thine is for sure, ill smoke a GT with either car. :devil:

I would think that the LS1 would have a better torque curve due to its longer stroke than the LT1??

yeah, thats the only lt1 that handed me my ass. I'm willing to bet he was on the NOS, cause it kind of came on all of a sudden. He pulled me about 1/2 car length at the end of 3rd, then in 4th it took about 4 sec to get another 2 cars ahead. I was pretty pissed, especially when he said all i got is CAI and a flowmaster! RIIIIIIIGHT! i dont know, what do you guys think?

Hes gotta be on the juice.

Having owned both engines, the LS1 defintely pulls harder up top and the LT1 had more grunt off the line. I speak, as do many others, with first-hand experiences in both cars.

Only if by more grunt off the line you mean its a weaker motor so it doesn't break loose in 1st or 2nd.

Having driven them both back to back, I don't think either "feels" particularly faster than the other.

The proof is in the numbers:

An ls1 will do 0-60 and the 1/4 mile AT LEAST a half a second faster in each category.

Where did you read this? I've never read it once.

maybe he's just talking about peak cince the lt1 has 325tq@2400 and the ls1 has 335tq@4000. the lt1 "feels" faster but the ls1 still is faster.

ok let me see if i get this right...
if both cars have 300 hp
weight pretty much the same
and have the same tranny and tires... then why on earth would you think either one would pull on either one???
my lt1 form runs 13.5 at 105
it dont put down 300+hp (285ish) cold air ,free mods, flowmaster , cutout, !about 100 lbs, lt4 km,airfoil,160 tm...and tuneing.... surprizes ls1's all the time....

the lt1 tq curve does not curve.... it is FLAT as a table(well all of mine have been)
the ls1 heads are WHY they make more power stock

whats the FASTEST N/A ls1???
joe overton has a 9sec N/A lt1....

my point is this... if you mod a simular displacment motor (lt1) to an ls1's same power so both are 300hp...
then the tq curves will look alot alike as well... (they will be alittle differant but not much) so if they make same hp and same tq and weight the same then they will stop the clocks at very close times(which one finishes first will be up to the driver)
now stock for stock there is no contest the ls1 blows the lt1 outa the water

"whats the FASTEST N/A ls1???
joe overton has a 9sec N/A lt1...."

9.7s I believe. I ran 9.82 NA with a hydraulic street cam and pump gas compression. Any LT1s doing that? :burn:

dont get me wronge colonel i know that the ls1's are very fast and i knew there where 9 sec ls1's..(good job on the hydralic 9sec!)
i believe joe ran 9.86
his best mph is 137.96!!!(and he did that foot braking thru mufflers on a stock suspention)(ls1's doing that?)
so the fastest ls1 is .1 sec faster ... if that....
true it means alot in the final match up of a shootout
but how many ppl make there best run time +/- .1? in any 3 runs??? most 3 runs are within .2-.3 which means on any given day he has a shot at ya...

but that wasn't my point...
the point is... equal power+equal weight+equal setup= close or same time slips
when modded to the same hp the lt1 and ls1 tq curve is much the same...
so how can one have an advantage over another???