View Single Post
Old 12-23-2009, 04:00 PM   #7
Bill Baer
Senior Member
 
Join Date: Jul 2007
Location: Nothern IL
Posts: 596
Likes: 1
Liked 1 Time in 1 Post
Default Re: Dragster Chassis Length

Quote:
Originally Posted by Tony Curcio View Post
Is there a formula or rule of thumb for determining the approximate wheelbase that will be best for a certain power level?

I've been seeing some interesting deals on E-Bay and such, and have wanted to put together a 4 cylinder dragster as a sort of rolling test lab, comparable to an F/D or F/ED. These cars seem to have a shorter wheelbase than any of the small block V-8 dragsters, like a C/D, and they are definitely shorter than most Super Comp applications. And then the Top Fuelers are over 300" long.

Looks like there's a correlation between available power and wheelbase. Can anyone explain it?

In particular, is a 220" wheelbase too long for a naturally aspirated 4 cyl with automatic?
Well Tony here's my 2 cents worth, The longer the wheel base the more flex you can build in to the chassis itself and most comp dragsters also try to run the narrowest rear tire possible (the less rotating mass the better) And overall the longer chassis will hook up better but you want to be as close to the min. weight for the class as possible because to some extent the cylinder head (flow) will dictatate the power you can produce so in general if your car is heavy (above the min) it will require more ci. but a bigger is not always a more powerful motor. I have seen some of these 4 cylinder comp dragsters with very little and or smaller tubing beyond the drivers area.
So My thinking is to focus on keeping it light and flexable with light having priority. The basic correlation is that the more power you try to put to the chassis the more it needs to flex. The reason all of the top fuel cars are 300" is because that's the max allowed by the rules . And if you study what's going on with comp dragsters you note that the A/D and A/ED cars are longer than the B/D or B/ED's and that they in turn are longer than the D/F cars. What the super comp guys are doing has nothing to do with max performance were about consistency (the larger the tire the better)
So a 220 wheelbase would probably fine if you could get it down to the min weight, but a 200" or shorter car is probabley lighter.
There may be some of then out there but I have never seen a land shark car in comp so I don't know if they would work with narrow rear tires.
I also have seen very few suspended cars in comp which I assume is due to the added weight.

For what it's worth.
__________________
Bill Baer 3391 SC, 339B SC, QR
Bill Baer is offline   Reply With Quote