Slow 5 speed 1/8th mile

[bgilbert]

Well, I got my speed up to 71mph and not quite as slow this past Friday at 11.24 . I'm not scared of 4wd anymore . I made 7 passes in 4wd. 1500-2500rpm 3rd gear launches. Of course after 3 or 4 passes the POS SBC FE got hot and would no longer hold anything . I think it could have had more to do with my driving technique than the clutch. I rode or let the clutch out too slowly and mostly the entire time. It's definately not the racing clutch, nor am I the 5sp racer.

Oh and it takes 5 passes to melt 44lbs of ice . Brian, I think if I continue racing with this setup, the tranny cooler will be necessary.. yeah yeah, you told me so:).

[CAJUN 93]

heavy vehicle, wide gear ratio's, low rpm motor. the cards are stacked against you . only thing you have going for you is 4wd launches.

are you only shifing once in the 1/8th mile? leaving in 3rd and crossing in 4th. what rpm are you crossing at. reason i'm asking is if you have some rpm to play with on the big end, you could put shorter, wider tires on to effectively lower you axle gear ratios. it will help get the mass moving and be a little easier on the clutch (simply because of the mechanical advantage). if your already out of engine at the end,this won't help at all.

if and when i build my drag truck, i'm thinking of installing a gm trans adapter and running a th400 with a brake. it's so much easier (and consistent) to load these things with an automatic.

daryl

[RumbleFish]

bill, where are you racing at?

[bgilbert]

Racing at Wabash Valley Raceway, I think it's called, at the Terre Haute (Vigo county) fairgrounds.

At first it launched hard and well in 3rd, shifted once into 4th and ran it out to about 3k rpm or so. Last dyno run I was making 350hp at 3800rpm, but for the most part I think the VE is about done around 3200rpm.

I'd have to check one of the calculator sites to figure up exactly what rpm I was at. 32" tires, 3.54 gears, 71mph, 1:1 trans ratio. If I remember right, from a glance it was around 3k rpm.

[DTanklage]

I would just barely stage and then launch early so it would start the timer about the time I hit 3rd.

huh? the et timer starts when the back side of your front tire exits the stage beam. does not matter when you launch in reguards to the ambers

don

[KTA]

My truck tire blocks the beam for about 12". If I just barely cut the beam I can roll 12" before the timer starts. If I am midways of the beam I can only get a 6" head start before the timer starts.

[DTanklage]

yes

this is referred to as 'shallow staging'

results are better 60' and et, but slower rt (reaction time)

but i still dont see how you can shift before the timer starts...

[KTA]

My truck eats the tires off in 2nd gear and really does not move. I never cliamed to have completed the gear change before the timer starts, but I am in the middle of it usually when it does. That is why I was launching as soon as the 2nd bulb came on and not red lighting because in .3 seconds my truck had not broken the beam yet but I had already built .3 seconds worth of boost and wheel speed. In reality I am probably in 3rd gear in 5ft.

[DTanklage]

on a .500 sportsman tree it is 1.0 seconds from the second amber to green

i guess it is just sitting there roasting the tires if you are not going red (getting a red light) and leaving that early

lol

thats funny to picture...

what is your name?

mine's don

laters

[CAJUN 93]

heavy truck, high torque, good clutch, hard launch= broken driveshaft, u-joint, or rear axle . it's probably better to spin the tires for 10-15 feet to get the mass rolling rather than try for optimum 60 ft times and deal with breakage. heavy vehicles require a different driving technique.

daryl

[DTanklage]

hey kta, have you tried starting in 3rd and sliding the clutch out?

kinda make it work like a tq conv in a auto...

not always, but almost always your 60' will improve (and so will 1/4 et) if you can get off the line w/o tire spin

don

ps - whats your name?

[dpuckett]

Pay attention, Don, you'll figure it out.

[DTanklage]

too broke to pay for anything...

[KTA]

The Name is Brian Block, but few people know me. I have pretty much given up on racing my truck in its current form with the twins, it either bogs and the turbo lag kills 60ft or it lights and annialates the tires and kills the 60ft. I know my truck would run in the 12's with a good 60ft, but it doesnt so I just play with it and make money off street races from people dumb enough to run a utility truck, especially a roll on.

P.S. I have a single disk clutch and I dont like to replace it so I don't slip it.

[DTanklage]

manual transmissions suck for drag racing - no tc to multiply at hit and no full throttle, no kill shifts

look at bg's truck - 11.25 = 18 seconds, maybe as quick as low 17's, but still, that truck has a lot of power and would be way quicker with a auto. dont know why he cant melt 40# of ice in one pass tho. that cooler must not be very effecient

if you guys put a nice auto in your trucks ($$$) and the tire to hook it they would FLY

you wanna build me a pump or are you too busy?

don