I have to say have got old and dumb. My sbc dragster has slowed 6 to 8 hundredths since last year with no changes. Fuel adjustments, timing and shift time showed no change. Simple suggestions please. Converter two years old. Builder said didn't think that it is the problem. Thanks for any replies.

Make sure your throttle cable hasn’t slipped. Seen that more than once. It’s become a habit for me to check that carb is opening all the way several times during the season.

Is the converter spragless? If it is you can rule it out completely. 8 hundredths is a lot. Do you notice anything else about i? Idle in gear, start , stall rpm etc etc etc?

Post some photo's of current and previous slips?

quote:

Originally posted by rerun:
My sbc dragster has slowed 6 to 8 hundredths since last year

That’s not necessarily cause for concern. That swing can happen from one week to the next depending on weather/track conditions and the fuel you run. Here in the northeast, we swing tenths on gas from spring to summer to fall.

my car lost .08 to .10 all of the sudden. ran good at end of 18,start of 19 it is slow. very consistent and raceable. worked great on the stop but bracket racing it would just not accelerate. changed everything from front to back. fuel, ignition, carb, timing. installed data logger over winter and noticed converter would flash right 6400, .5 in to run flat line at 6000 for 1.25 sec then start to go. rpm drop at shift was right so you think motor is not making power making conv. look tight.

Not so. Reitow is on to it I think. sprag may be slipping in converter if it has sprag. if spragless I don't know. I changed converters and mine went right back to where it should be.

when this was going on it would run within a few numbers all year no matter what the air conditions where. it was good but weird.

ep

Have you blown out the fuel lines? I knew a guy had a lizard in his fuel line, spun him out for a few races, 8 hundredths slow.

I agree with Ed, especially if you run on gas. If you are comparing your last run of Fall 2019 with cool dry air vs the heat and humidity of June 2020, that swing of less than a tenth wouldn't scare me. DA could be 3,000 feet different (or worse). If it was in comparable atmospheric conditions, then I might be thinking Converter, Tires, etc.

Car has Ron's Toilet injection. Pump is Enderle style new in 18. Clean all fuel related items Friday. Don't remember if converter has sprag, I think it does. Some of the recent runs feels like it lays over a little before shift. This thing ran 5.45 or .46 most weeks the past two years. Now the past 5 weekends 5.517 to 5.539.

quote:

Originally posted by rerun:
Car has Ron's Toilet injection. Pump is Enderle style new in 18. Clean all fuel related items Friday. Don't remember if converter has sprag, I think it does. Some of the recent runs feels like it lays over a little before shift. This thing ran 5.45 or .46 most weeks the past two years. Now the past 5 weekends 5.517 to 5.539.

Send the torque converter to Transmission Specialties in Aston PA, have it made spragless. Ask for Justin. Tell him I sent ya he give ya a few bucks off. They'll do a wonderful job for you. Great work, it's what I run Transmission Specialties spragless. Fastest N/A sbc converters around 1.27 60 ft 3250 lbs.

quote:

Originally posted by rerun:
Car has Ron's Toilet injection. Pump is Enderle style new in 18. Clean all fuel related items Friday. Don't remember if converter has sprag, I think it does. Some of the recent runs feels like it lays over a little before shift. This thing ran 5.45 or .46 most weeks the past two years. Now the past 5 weekends 5.517 to 5.539.

So your dragster has only varied .01 in 2 years?

must be true, we read it on an internet forum.

quote:

Originally posted by 1320racer:
must be true, we read it on an internet forum.

I mean i run on methanol my car can swing 2 tenths fall to summer... What am i doing wrong lol

exactly! the nonsense some people post here, like claiming a carb spacer will have you running 3 tenths quicker than without it.

quote:

Originally posted by 1320racer:
exactly! the nonsense some people post here, like a carb spacer claim that will have you running 3 tenths quicker than without it.

In the right hands Ed.

Ya don't see anyone else running like this sbc, 3250lbs, 10 x 28 bias slick, n/a.

Transmission Specialties spagless 8" quickest sbc converter around.

**** sell me a spacer that will give me 3 tenths lol

exactly, mickey is a liar and a tool!

A .3 reduction in et is approx 300 hp depending on the car....no way in hell you're going to bolt on a spacer and pick up that much...If that were the case, every racer in the country would be scrambling to add spacers to their cars instead of building new combos, changing cams, compression, supercharging, etc.....

I say to put this one to bed, lets to an A to B test as previously suggested. Take said car, remove spacer, make a pass. Photo time slip....Then add spacer, no other changes to car other than adding fuel if required. Make another pass....photo time slip....IF there is a .3 difference, with no significant change in the weather, then it's documented and proven. If not, then it's disproven....simple as that.

A video without time slip isn't proof. A time slip with partially covered up information isn't proof..no a to b runs and proof of runs isn't proof...I can say all day long I ran a 6.20 after adding one degree of timing on my junk, and I bet I can get a time slip to substantiate that (not mine of course)....but unless you have proof it was MY car on the slip, and WATCHED me make the runs and changes, it's all BS......

Hell, my buddy back in Denver just did that to me...He was testing his new funny car two weeks ago, and after his first run, messaged me what he "ran" and sent me a pic of the time slip......I didn't notice at first, but he conveniently had his thumb over the car number......turns out he used the timeslip from another car parked next to him to play a joke on me.......I called him on it because I know his combo and knew better, but that's an example......

quote:

Originally posted by RacerVX54:
**** sell me a spacer that will give me 3 tenths lol

Ed is taking that out of context purposely because he has no evidence to back up anything he says.

We were discussing picking up 12 hp with a spacer, 15 hp with a vacuum pump, 10 hp oil, etc, etc etc,

How it all adds up.

This message has been edited. Last edited by: Mike Rietow,

Ed, who has the quickest / fastest 8" spragless torque converter 3250 lbs sbc n/a?

The original is still the best eh?.

Sorry to bother any of you. As I stated up front old and dumb.