Firts of all i got a 95 formula, but i must say how the hell do ALOT of lt1 i see run like low 13s to mid with full exhaust , DR and gears and other bolt-ons......i would figure a 350 with those mods should be running mid to high 12s easy

i aint dissing them or anything but to me that is horrible
i just want to know why they are like that...i know the heads arnt to good and the cam isnt either but i also see some with a cam only run like high 12s....

but at the same time i seen some run like 11s with stock heads and low 12s...but in general i see 13s

also i seen so many diffrent dyno numbers from the same mods

like some get 310rwhp with full exhaust and some get 280rwhp
and with a cam i seen some get 310rwhp and some get 355rwhp and are both dyno tuned

just help me understand more

 

There are more factors in that scenario than I could ever get into. The main ones are probably driver skill(M6 especially),track conditions,weather conditions,elevation,the car's actual tune(like if it's in need of a tune up),etc. Not to mention gears,tires,combination of any mods, etc. I've seen two cars with almost identical mods and the same tranny run 3-5 tenths different at the same track on the same day. Just depends on which tires they're using, their actual skill and driving habbits. I know dang well someone who's been down the track 5000 times will be able to get 11's out of a car that's capable, take someone else who's been down the track 5 times, or even none and they might have a hard time getting high 12's with the same car. Theres a lot to consider.

 

I would guess it would depend on what the setup is.. Two cars are never really setup the same way.. It also depends if it was beat on and the condition of the internals.. maybe those low horse power cars your talking about are loosing compression because of worn piston rings.. It can be a number of things.. driver as well..

 

It matters what kind of cam there running also if there running shorty/mid length/LT headers. gearing plays and important factor, along with race weight. The condition of the motor, miles etc. and if the driver is experienced with track driving. Conditions of the track at the time and altitude play a huge roll also. Hope this helps.

 

off course drivers make a diff....but im talkien about ppl getting about the same 60 foot 1.8-2....also i know setup is a diffrence but with the same mods iv seen a 30rwhp diffrence

 

Like someone else said before, running condition has a huge role in it. Some people like to start modding before they get everything else in a good tune. Mileage and internal condition was also mentioned, and that plays a major part as well.

Auto's and manuals also have different parasitic drivetrain loss numbers.

 

basically Dyno's are a tuning tool,every brand dyno reads differently. People on this board like dynojet,because they offer up the highest hp numbers when compared to a brake type dyno.

also,as said above,weather,tuning,general condition all play a role in the hp dyno game.

Also it doesnt help that these cars are HEAVY,3500lb without driver isnt uncommon,nor lightweight.

I have gone 12.36@109 with full bolt on's,stock heads/cam.

 

IMO, high 12s and even low 13s is a bit optimistic with just the standard bolt ons. For most, if you want to get in the 12s with an LT1 you are looking at doing a cam or cam/heads.

If you figure a stock LT1 runs around 14.0 to 14.3 in the 1/4, you are looking at over 100 rwhp to get down in the 12s from that. Standard bolt ons aren't going to give you that kind of power IMO.

 

It's all in the heads. LT1s have terrible heads. All the LT1 really needs is LS1 styled heads to hit their times. Even after mods, air still have flow through the crappy heads. Check out some LT1s with AFR head swaps... they're running excellent times.

 

very true, i noticed everyone with afr heads have awesome times and great RWHP #'s... Wish i could get a set of them, but right now with money being short, im stuck with stock heads not even ported.. and i know that will limit my times BIG time :/

oh well.. still enjoying :/

 

Lt1's do not have crappy heads, The tune and cam are a compromise between performance and emissions If you take the stock flow numbers and compare them to a standard old school 350 head [even double hump] there is no comparisson the lt1 head is a vast improvement.Thats why they wake up with a mild port and larger cam,the heads are able to take advantage of the extra flow provided. Case in point I ported my own heads and with only a cc305 have hit 12.0s, Its only because the heads and cam make good numbers.

 

I'm talking about bone stock heads, no porting at all. It was in response to the topic starters question of why bolt-on LT1 cars run crappy times. Most don't consider ported heads, home or cnc, a bolt-on modification.

 

That said, the stock LT1 heads flow well for an SBC head. Better than the old style, but not as well as the LS1. The iron ones flow better....

 

Actually, LT1 heads are the best SBC production head ever made (besides the LT4) up until the Gen III motor (LSx). 4th gens are heavy though, that's why they run the times they do. But the LT1 is a damn stout package considering the "old" technology and high emissions standards it had to meet.

Rich Krause

 

Seriously...I think it's because of "Suspension" that so many peoples times vary...you'd be surprised how much that matters when taking off the line in one of these cars...like adding a supercharger or something. IT's like a totaly different feel.