Need advice for slowing my car down consistently.

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flyfish

flyfish

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I normally run in Pro, but this year I’m going to run Sportsman. The “short” reason is, I only race with the money that I save over the winter, and this year (thanks to breaking my rear end last year) funds are in short supply. I could either race part of the season in Pro, or the pretty much the whole season in Sportsman. The bottom dial for the Sportsman class is 12.0, but my car is capable of running 10.7’s….So, my question is, has anyone slowed their car by over a second with good results (consistent, round after round)?

I was thinking of either adjusting my throttle cable so I only get about half throttle and trying it, or putting a block under the gas pedal. Has anyone tried either of these, and did you have success with it?

Another option I was considering was putting an adjustable dead stop on the carb that could be removed remotely using an old choke cable. So, for example, if I was running down the car next to me and needed my whole gas pedal (a little extra power to take the stripe) I could just “remove” the dead stop with the pull of the choke cable. I don’t think this would be considered cheating, but what do you think? The class rules say a dead stop is legal, and everybody and their brother has a nitrous system on their car for “just in case I need it”, so I think it would be OK in comparison…but I don’t know.
 
I see you run pump gas and I,m wondering what the cost differences are with running 10.70 or 12.00 ?? Parts breakage?I would think to change to a 12.00,you might wanna change converters,gears.It would be pretty hard to run consistant unless you have some type of throttle adjustment to fine tune to a 12.01-02.Maybe the block under gas pedal will work?Good luck.

Do you run MSD with rev-limiter?Lower the RPM pill to rev...say 4500-5000??
 
Sorry, I should have clarified, this is just a temporary change so I can compete all year in a points series. I want this to be a simple change that I can swap back easily and run the normal 6.8's in the 1/8. I'll be switching back next to Pro next year more than likely. Also, I really don't want to spend any money making it go slower; otherwise I might as well use that money and run Pro like usual.
 
Yes, I have an MSD with a rev limiter, but with a 5000 stall I would not have much room to chip it down. I think if I chiped it to 5500 it would still run mid to low 11's.
 
* Chipping it on the top end is very likely illegal - "stutter box".


* You can disconnect the back barrels which may slow it roughly 1/2 second and/or make a bracket with shims under the pedal.

* If you have a choke-type deal to remove a "throttle stop", you gotta be sure there isn't any chance of it somehow hanging the throttle open.

* Regardless of how you do it, any efforts to significantly slow a car down will reduce it's consistency. Mainly it makes the engine more sensitive to temperature, humidity and wind conditions. That's one reason why most Stock class winners are in the faster classes. Slow cars can still win and they do, it's just harder. Of course you'll be running against slower cars which will help your cause. But it's something to consider.
 
Locomotion said:
* Chipping it on the top end is very likely illegal - "stutter box".
Correct, down track stutter boxes are not legal in this class.

* You can disconnect the back barrels which may slow it roughly 1/2 second and/or make a bracket with shims under the pedal.

* If you have a choke-type deal to remove a "throttle stop", you gotta be sure there isn't any chance of it somehow hanging the throttle open.
Yes, the ONLY way I would attempt this is if there was NO WAY it could possibly make the throttle stick open.

* Regardless of how you do it, any efforts to significantly slow a car down will reduce it's consistency. Mainly it makes the engine more sensitive to temperature, humidity and wind conditions. That's one reason why most Stock class winners are in the faster classes. Slow cars can still win and they do, it's just harder. Of course you'll be running against slower cars which will help your cause. But it's something to consider.
Click to expand...

Thanks Locomotion, all good points to consider.
 
a friend of mine made and adjustable throttle stop that seemed to work great for him in the 12.0 classes.
 
I would give Brett a call at www.restrictorplate.com/. he runs his 10.00 firebird in pro and sportsman, you tune with different quick change plates and He will set you up. it takes 3 seconds to change out the plate for different ETs. Brett is a good friend and he wins alot of races with his restrictor plate.
 
I run super gas in my 1970 cuda and use a throttle stop to slow it down from 8.70s to 9.90s but I doubt this would help you. you would need a computer and elec. + a weather station
 
if all else fails...the best thing i found out for slowing a car down...Is to work on it...

Always works for me....LOL
 
It would only help a little bit, but there's always the option of adding weight - approx. 100lbs per .010. Of course you can only do so much and it needs to be done safely and legally. Best thing about it is that it would help quite a bit against spinning!

Less gear and/or taller tires? But that's getting expensive.
 
My friend lengthened his throttle cable so he would not get wide open throttle. It worked perfectly.
 
Fly, I've been monitoring the thread. Some good idea's. My first thought was to go with a 390 4bbl or a 500 2bbl, but I doubt even that would slow you enough and it would still be cash out of pocket.

I assume the main issue your dealing with is entry fee's. Would it be possible to pick up a small sponsor for a spot on the car to make up the difference? A friend with a business or a local small business maybe. I'd help if I could. Good luck however it works out.
 
Thanks for the all the ideas folks. OldmanRick, yes, it is just the cost of entry fees. I spent money I didn't have to fix my car last year, and I refuse to let my hobby put me in debt...so I used my normal racing funds to pay off my credit card debt that I incurred by fixing the rear end (broke it second race of the season last year). So, I'll go back to racing Pro next year, but this year I'm going to try something new...Sportsman...I believe I'm just going to try moving the throttle cable. It sounds like the easiest way to accomplish the goal.

Took the car for a drive for the first time in 6 months yesterday....it was GREAT....and the track opens next week :cheers:
 
The best way I know of is a stop , usually at the carb on the linkage.
But a friend ran super comp with some success using a bolt in the foot feed , preventing it from going wide open.
Easiest and cheapest.
A restrictor plate would sure work.......I have heard good things about using them , but they would run a few more bucks.
Over at moparts , Mr. Peabody made a simple stop that went on a carb stud and worked like a champ. There is pics in some of his replies on the same issue.
 
tubtar said:
The best way I know of is a stop , usually at the carb on the linkage.
But a friend ran super comp with some success using a bolt in the foot feed , preventing it from going wide open.
Easiest and cheapest.
A restrictor plate would sure work.......I have heard good things about using them , but they would run a few more bucks.
Over at moparts , Mr. Peabody made a simple stop that went on a carb stud and worked like a champ. There is pics in some of his replies on the same issue.
Click to expand...

simple answer: go ahead and run pro, just win more!!
 
First off, I just want to say your a good man for not sacrificing the family budget. Well done!

I'm assuming you will have to adjust your staging, "deep" and launch rpm to make this work with a throttle stop. Have you considered leaving in 2nd and just using 2&3? Not sure i'd like being on the converter that long and building the heat, but if it knocked off 3/4 tenths, you may be able to run a hair more throttle with the stop?

I hope you get a few T&T's in to try and figure it out. Dial in choice is gonna be even more critical and I hope your brakes are in good working order....lol. If you start winning in Sportsman with your car, i'm sure you wont make many friends there. :D

Please let us know how things work out when you get some passes and some data.
 
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