ET reduction

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mikedevore

mikedevore

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Trying to come up with a way to slow my car down.
Going to the Team finals in late October in Dallas.
The car will be running in the 7.0 range 1/8th mile.
I would like to slow this thing down to 7.50 to move it away from the fast cars.
Any thoughts on replacing the 750 Holley with a 500 two barrel on ET reduction?
My thought was that it would retain the 60ft time with the 500 & slow on the back end.
Open for suggestions.
 
If a double pumper, you could try disconnecting the secondaries, or modifying the linkage to only open part way. I race with a guy who does this to stay in a certain class.
 
short shift it by 1000 rpm's. this will slow it up some and save motor parts
 
Adjustment of the throttle cable,trial and error( if you have time). This,would give you confidence,off the line knowing it's set.
 
Well, having just finished doing this for the past season, this is what I did to take my 10.80's car up to 12.0's in the 1/4 (6.80's up to 7.70's in the 1/8 ).

Below are the things I did and what time it shaved (every car is different, so you will have to practice to see what works on your car):

Added any and all weight safely to the car = 0.2 seconds.
Disconnected secondaries = 0.4 seconds.
Short shift @ 5200 RPM = 0.2 seconds ish depending on whether or not I did the next step....
Launch in second gear = 0.3 seconds.
Retard timing to fine tune = 0.1-0.3 seconds depending.
I also used a really small restrictive air-cleaner on occasion that would shave another 0.12 if needed.

I will note that the second gear launch takes a bit of getting used to to cut a good light, I would only use that as a last resort....but it is WAY fun if you have someone next to you with almost the same ET because your 60' time will SUCK which makes it look like you missed the tree...then your car will come on HARD on the back end with a LOT of MPH for the ET you run. This helped me win a LOT of rounds this year in sportsman. For example, at the Division 3 ET finals the past weekend I dialed a 12.04, my 60' was in the 1.84 range, and my mph at the stripe was be close to 116 :D.

The short shifting can be tricky....if I missed by a few hundred RPM my ET would change anywhere from a few hundredths to a full tenth.

For what you want, I would just disconnect the secondaries, short shift and see where it lands....probably will be in the high 7.40's....then either add weight or pull a little timing to fine tune it.

Good luck!
 
Can't remember what it's called but it is a plate you install under the carb to slow it down. Basically a restrictor plate you can remove or change in less than a minute. I have it saved on my other computor but don't have access to it now.
 
jefflock said:
Can't remember what it's called but it is a plate you install under the carb to slow it down. Basically a restrictor plate you can remove or change in less than a minute. I have it saved on my other computor but don't have access to it now.
Click to expand...

ET genie....yeah, those are close to 500 bucks.
 
EZ Plate System. Yep $500
 
Good advice from everyone.
I plan on going to test before we go to Dallas.
Disconnecting the secondaries & adding some weight might be the first thing I try.
Thanks Guys.
 
damn 500 bucks to slow the car down,**** pull a plug wire...
 
How hard is it on the transmission & convertor leaving in 2nd gear?
I run a 904 trans & 8" Coan convertor, with a 4:30 gear.
 
When I want to slow my car down, I throw on my bias-ply slicks (good for a tenth or two) and adjust my throttle cable back.
 
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