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Sun Aug 17, 2014 5:04 pm

Has anyone had any experience racing mile drags? If so how did you or would you set up your engine to go balls out?

Sun Aug 17, 2014 5:07 pm

You might want to talk to land speed racers. They should know everything about how to set up your car.

Sun Aug 17, 2014 5:19 pm

The biggest difference will be in the gearing.

Sun Aug 17, 2014 6:33 pm

Check over at the Vintage Speed section. Theres some land speed challenge topics there.

Sun Aug 17, 2014 7:09 pm

Are you takling 'Texas Mile"..... Its going to take horsepower and gearing.....Same as dry lakes or salt flats type of racing where top speed is everything---......

Its not a one mile "drag race" in sense of a 'drag race' is two cars dueling it out side by side over 1/8 or 1/4 mile where et (elapse time) and reaction time off the line determine winner.....

Dale

Sun Aug 17, 2014 7:20 pm

Yes, the Texas mile in Beeville.! I would like to go with a 1776 or 1835 with a freeway flyer tranny. Do you think that would suffice? I want more hp than the 36 hp land racer

Sun Aug 17, 2014 9:19 pm

I'm building a 68 Bug...turbo charged 2052cc engine, dual 44IDF carbs...I'm shooting for the USFRA 130 MPH club, Texas mile and the Silver State Classic 95MPH class. The trans has a .82 4th gear, 3.875 R&P, and I'm running 25" front runner drag tires. It takes money to go fast...More money to go faster!

Mon Aug 18, 2014 2:32 pm

Make sure you do everything you can to keep the heads cool since you'll be at WOT for awhile. Mine easily spikes to 400 at the plug on shorter runs (~1/4 mile) up to 80-90 mph.

Mon Aug 18, 2014 4:23 pm

Put a water misting system into the cooling fan to keep the heads cool.

That's what Black Line Racing does to run the salt flats. RV water pump will supply enough pressure to run a few patio misters.

You can also run a set of AC.Net's Super Squishy pistons. Build it right and it takes a LOT of heat out of the combustion chamber. Me and a friend are both running 24lbs of boost on 91 octane. They work.

Wed Sep 09, 2015 4:47 am

Are you going to the mile next month?

BGEE68
PostPosted: Sun Aug 17, 2014 9:19 pm Post subject:
I'm building a 68 Bug...turbo charged 2052cc engine, dual 44IDF carbs...I'm shooting for the USFRA 130 MPH club, Texas mile and the Silver State Classic 95MPH class. The trans has a .82 4th gear, 3.875 R&P, and I'm running 25" front runner drag tires. It takes money to go fast...More money to go faster!

Wed Sep 09, 2015 9:19 am

mister and a bottle thats kinda rich on the tune. :wink: and of course a retard. :shock:

Wed Sep 16, 2015 4:09 pm

From personal experience, what seems to work best for LSR (Land Speed Racing), is starting with a gear calculator and selecting a suitable 4th gear for the speed you need to go, at the max rpm you expect to reach with your engine combination. You have to be realistic, but as Stephen Covey used to say "Begin with the end in mind". Working backward from you selected 4th gear, R&P and rear tire diameter combo, paying close attention to rpm drop at the 3-4 gear change, select a suitable 3rd gear. Same with the 2-3 shift, but the 2-3 shift is a lot less sensitive to rpm drop, because of torque multiplication. The 1-2 shift even less so.

I'd want as tall a first and second gear main shaft set as I could find for the salt and dry lake beds, since traction is limited. I'd start with a 3.88 R&P as well.

Make the rpm drop too large at the 3-4, just like in drag racing, and the engine will take too long to 'dig itself out of the torque hole' that it goes into when the engine drops out of it's power band (read: Bwhaaaaaaaaaaaa...) . I've seen guys loose 10 - 20mph of performance in the 1 mile at Bonneville because of too much RPM drop between 3rd and 4th, the engine never recovers, and the car stops accelerating at the gear change, when it should be maxed out at the finish line stripe.

Your typical 'freeway flyer' deal wont work very well for LSR, because of the typical big rpm drop between 3rd and 4th.

Wed Sep 16, 2015 4:35 pm

I would think Safety would be a real concern. A roll cage, 5 point harness, a fire control system, and tires rated to run the speed you are looking for, along with clothing that's fire retardant, helmet, and a host or other required items.

Wed Sep 16, 2015 4:43 pm

Go big and do a 2110 with dual valve Springs and with a 3.88 R&P with a .82 4th....RB

Wed Sep 16, 2015 4:53 pm

Bugs get real iffy above 135 and start needing aero help with front and rear spoilers -- at the minimum a Herrod's Helper -- but more is better -- several guys run buggy's --

Here's my LSR -- -- 2989 turbo'd 091 trans with a .77 fourth -- wish I had went with the .70 -- In the 300 HP range -- I've been doing more autocross with it lately as there are a ton more events to attend and I love kicking some V8 butt..........

Wed Sep 16, 2015 5:37 pm

Is your objective ET or top speed? I am not sure if the Mile racing measures both...? (You will be at max speed before a mile so I guess my question doesn't matter!)
For LSR/Salt, gearing is critical; if you use an IRS chassis you can do relatively quick gearbox swaps to change your overall (diff x 4th gear) gearing... then chase the last one or two percent with a rear tyre change

Wed Sep 16, 2015 7:55 pm

Here's a link to the 57 I built for Bonneville. A big motor is one thing but having the a well handling car is a must for high speeds, and on the runway courses BRAKES should be your first upgrade as they have fairly short shutdown areas compared to Bonneville. Never had a problem with head or oil temps over the mile, Oil never cracked 190 and head temps were around 350-375 with stock cooling.

http://www.thesamba.com/vw/forum/viewtopic.php?t=483669&postdays=0&postorder=asc&start=0

brad

Thu Sep 17, 2015 7:13 pm

Brad IS the MAN!!!

Listen to his wisdom!!!

Thu Sep 17, 2015 7:57 pm

Fiatdude wrote: Brad IS the MAN!!!

Listen to his wisdom!!!

Thanks, but no I'm not THE man. I just have 3 events under my belt and some very good friends who have helped me out.

We all kind of pool our experiences and help each other out so we all gain knowledge fairly fast which is very good because when you only run once a year (or every 2 years like me) and only get 6 runs in at an event the learning curve is VERY steep. Finding out what works and what doesn't and what to expect before you even get there is a HUGE advantage. And then when you are there having people like Tom Bruch, Gaylen Anderson and Burly Burlile being able to impart their vast pool of knowledge and experience is invaluable.

But thanks for the kudo's.

brad

Thu Sep 17, 2015 8:29 pm

RailBoy wrote: Go big and do a 2110 with dual valve Springs and with a 3.88 R&P with a .82 4th....RB

If that is your spec, how fast did it go?
What car was it in? Tell us more!