another race question
02-18-2009, 04:20 PM
#22
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02-18-2009, 04:48 PM
#24
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LS1, notice no intake cover and coil packs on the valve covers.
Last edited by 83gtragtop; 02-18-2009 at 04:50 PM.
02-18-2009, 05:33 PM
#25
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I think that LT1 Trans Am is going to have a rearveiw mirror full of Mustang headlights. The LT1's Make real nice low end power (better than LS1's) where the LS1's start shinning past 3500 rpm. The LT1's also responded very well to very slight mods. A K&N cold air kit picks them up 20+ hp at the wheels. The hypertech tuner can get it another 15-20 hp at the wheels. I did a lot of work to the LT1's when they first came out and if you try to run him as is it's going to be a slaughter if his car is running on all eight. Your only hope is if that little 7.5 rear end under his T/A lets go. You are out gunned on this one.
the lt1 torque peak is like 2800 or so, its pretty low. the ls1 torque peak is 4500 or so, and is relatively high. so people assume the lt is torque happy and the ls is a high breather. but no
at 2500 both motors, according to the graphs we pulled, make about the same torque, ~290rwt. from here the lt1 starts to fade slowly, while the ls1 rises slightly until it hits around 300-310rtw around 4500. so really, at ANY point in the powerband, the ls1 is making more torque than the lt1, which makes sense since torque and hp are just angular and linear equivalents (kinda).
another factor is that the ls1 head allows for higher valve overlap and higher lifts while still making power, so people put cams in these motors that would make any other stock SBC crawl in a corner and cry. one thing about high rise cams is that the torque curve is shifted higher, much higher. so stock the ls1 is torquier, but after a massive cam swap it may be making only 200rwt down low. I lost TONS of torque down low after my swap, but the extra 1000rpm and extra hp makes up for it in a big way.
Brand new 95 Z28 Automatic 13.20 right off the truck on street tires. Cold Air kit and Hypertech 12.95s. Edelbrock 50 state legal headers and SLP Cat back 12.60s. Drag Radials 12.40s. Those cars are very responsive to the slightest mods. They were only rated at 275 fwhp. I've seen one bone stock lay down 280 at the wheels. They were a nightmare to Mustangs when they came out. The biggest plus to those cars was the low end torque. I have to give credit where credit is due.
they were rated for 275 bhp, and typically dyno (and ive seen this myself) around 240rwhp (not fwhp which means front whell.... wtf
) depending on the dyno. In fact the lt4 conversion nets about 290rwhp using the stock grand sport cam, which is much better than the stock lt1 cam and valvetrain.the only reason they were a nightmare to mustangs when they came out is because the mustangs at the time were the 302 making 215hp, or the 4.6 npi making the same. it wasnt till 99 when the stangs closed the gap... on the older ones... but by that time the 300rwhp ls1 was out. dude, ur figures are just straight from fairytale land
check the pic above me, thats the best way. ls1 has plastic loopy intake manifold. lt1 has a metal manifold. if its red that means he has probably had an lt4 conversion which, as i said earlier, is good for 290ish rwhp, unless hes got the hotcam or bigger and then maybe hes anywhere up to around 340rwhp. but u would be able to hear the cam loping
Last edited by SpecterGT260; 02-18-2009 at 07:06 PM.
02-18-2009, 05:53 PM
#29
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S/S? dude, its a trans am 
and who the hell says fwhp for fly wheel? this is the first time ive heard this, and ive been into this stuff awhile.....
bhp stands for: I actually know what im talking about when i speak w/ my mouth... er.. um... hands, in this case
and who the hell says fwhp for fly wheel? this is the first time ive heard this, and ive been into this stuff awhile.....
bhp stands for: I actually know what im talking about when i speak w/ my mouth... er.. um... hands, in this case
02-18-2009, 06:40 PM
#30
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For those 5.0 guys who don't know.... S/S= Street/Strip section here at mustang forums.
Also, typically FWHP stands for FrontWheelHorsePower
ie. Bob's Civic made 119 fwhp on the dyno.
Last edited by 83gtragtop; 02-18-2009 at 06:42 PM.