The Cal-look Lounge

Cal-look/High Performance => Pure racing => Topic started by: Trond Dahl on February 02, 2015, 15:53:53 pm



Title: Pre-loading before launch
Post by: Trond Dahl on February 02, 2015, 15:53:53 pm
What is the best way to pre-load suspension, gear/axles before launch? Rear or front wheels?
As discussed in other threads some people use line locks(front) and some use staging brakes or parking brake(rear). What do you think is best and why?


Title: Re: Pre-loading before launch
Post by: Neil Davies on February 02, 2015, 19:24:21 pm
Trond, I always used the handbrake to stage on and pre-loaded the gearbox that way. Ran a stock '66 gearbox for a couple of seasons, 8 meetings a season without any gearbox breakages, just with a 1584 running into the 16s. Put the close ratio box in and ran a season with the 1584, followed by a 2180 and two 2276 IDA motors. Had 6W slicks and 1.55ish 60 fts. When I broke the engines (did three in three years!) I put the 1584 back in and carried on racing! I had the box freshened once but never broke it, and put that down to pre-loading it on the handbrake.


Title: Re: Pre-loading before launch
Post by: JS on February 02, 2015, 20:46:00 pm
Trond, I also always used the handbrake to stage on.

It works for me, therefore itīs the best way.  :D


Title: Re: Pre-loading before launch
Post by: Trond Dahl on February 02, 2015, 21:40:48 pm
I use the line lock on my beetle and I am happy with my procedure. But now that I am building my Ghia I am wondering about a staging brake vs line lock.
One thing is what we have available and prefer. But I'm sure the must be a "best" solution because of ......?!?


Title: Re: Pre-loading before launch
Post by: Type1/DVK on February 02, 2015, 21:55:51 pm
handbrake pre-load, stock box '64bug, with 130hp 1776 no problems :D  14.74s @402


Title: Re: Pre-loading before launch
Post by: Erlend / bug66 on February 02, 2015, 21:56:51 pm
 In my mind a line lock would tilt the car forward, and the hand brake pull down the whole car (or atleast the rear)

Or?


Title: Re: Pre-loading before launch
Post by: BeetleBug on February 02, 2015, 21:57:31 pm
Some like the mother, other the daughter.

My personal opinion is this:

One pre-load the trans and the other the whole car. After the burn out I roll the car to the pre-stage. Hit the brake pedal and lock it with the line lock then push the car to stage. I follow up by letting the clutch out to where it starts to grip. The car is now pre-loaded and ready. Or just take a look at the one of the fastest guys out there:

https://www.youtube.com/watch?v=rX49ZczJZPM

Best rgs
BB



Title: Re: Pre-loading before launch
Post by: Trond Dahl on February 02, 2015, 22:04:15 pm
That is exactly what I do today, but I'm looking for the technical correct way. But maby there is none?
I would expect rear preload to squat more/more wheelie?!


Title: Re: Pre-loading before launch
Post by: reijo5 on February 03, 2015, 19:50:50 pm
Some like the mother, other the daughter.

My personal opinion is this:

One pre-load the trans and the other the whole car. After the burn out I roll the car to the pre-stage. Hit the brake pedal and lock it with the line lock then push the car to stage. I follow up by letting the clutch out to where it starts to grip. The car is now pre-loaded and ready. Or just take a look at the one of the fastest guys out there:

https://www.youtube.com/watch?v=rX49ZczJZPM

Best rgs
BB

That s a fast few seconds of work , great video




Title: Re: Pre-loading before launch
Post by: richie on February 03, 2015, 20:03:05 pm
My personal opinion is this:

One pre-load the trans and the other the whole car. After the burn out I roll the car to the pre-stage. Hit the brake pedal and lock it with the line lock then push the car to stage. I follow up by letting the clutch out to where it starts to grip. The car is now pre-loaded and ready. BB




What do you think is the advantage of pre loading the car as opposed to the drive train only? I just can't see it


I have always used the handbrake, new car I use staging break but still on back wheels, I only have one experience of using a linelock on front wheels and I found it a real pain in comparision to handbrake

Trond I don't think you need to pre load it enough to squat the car down, just enough to mesh the gears and axles, just my experience anyway :)

cheers Richie


Title: Re: Pre-loading before launch
Post by: BeetleBug on February 03, 2015, 20:19:59 pm
What do you think is the advantage of pre loading the car as opposed to the drive train only? I just can't see it

I have always used the handbrake, new car I use staging break but still on back wheels, I only have one experience of using a linelock on front wheels and I found it a real pain in comparision to handbrake

Trond I don't think you need to pre load it enough to squat the car down, just enough to mesh the gears and axles, just my experience anyway :)

cheers Richie

Thanks Richie,

I used to stage using the E-brake and changed to line lock after a while and I personally feel that there is a noticable diffence but thats me. I guess it is one of those things combined with old habits etc... much like venting from the valve covers  :) We have discussed this earlier here on The Lounge:

http://cal-look.no/lounge/index.php/topic,4713.0.html

-BB-


Title: Re: Pre-loading before launch
Post by: melvin on February 03, 2015, 21:55:43 pm
i always use the handbrake, for me its better than use the line lock . i think u most use the best option for you and not listing to other. everybody drives on his own way  ;)


Title: Re: Pre-loading before launch
Post by: Jonny Grigg on February 04, 2015, 21:48:25 pm
I use a line lock on the rear brakes as it conveniently also acts as a really expensive T piece. I stage the car exactly as everyone else does to load the trans, but the line lock is wired into the button on the vertigate, which has the two step.

I also have a line lock on the front circuit for burnout, with a toggle switch to change the shifter button function.

Confusing, but it works for me.  :)


Title: Re: Pre-loading before launch
Post by: Roman on February 05, 2015, 21:58:51 pm
I do like BB, with a small difference- I have a brake pressure gauge so I don't risk to lock up the front wheels.
One of the pros is that I don't have to move my hand from the shifter.


Title: Re: Pre-loading before launch
Post by: Dougy Dee on February 06, 2015, 14:22:33 pm
Wouldn't swing axle cars respond differently than IRS? I'm thinking of 'squat' or settling the car on or near the rear snubbers.


Title: Re: Pre-loading before launch
Post by: Dead Dog on March 03, 2015, 21:48:59 pm
I have a line lock for fronts
I have gone over to a hydraulic hand brake for staging, that also via a brake pressure switch engages launch control, simple and works well


Title: Re: Pre-loading before launch
Post by: Turbo_Rich on March 08, 2015, 23:05:03 pm
I used to use the handbrake for prestaging, it preloaded the box and worked fine even having to depress the button. (it also had a micro switch which activated the launch control/2 step)
(http://farm3.static.flickr.com/2458/3969534396_b5364c062f.jpg)

However as I started upping the power I discovered I could not change from 1st quick enough after launching (having to drop the handbrake and reach forward for the shifter) I now use a line lock with the button on the shifter. I get almost at pre stage dab the brakes hold the button then push the car into stage. The button now also activate the 2 step. I find this much easier for launching now and don't have to worry about the car creeping on the hand brake. It does take a bit of practice to get used to releasing the button though!


Title: Re: Pre-loading before launch
Post by: dannyboy on March 08, 2015, 23:22:57 pm
its a funny one ,i did the opposite used to use linelock to preload ,then went over to the handbrake and found it much easier to use .rich do you hold in the button or lock it in with tape or a pin? if not that would be a real pain to relase handbrake as all i do is let go and grab gearstick if the button isnt locked in you would have to keep your thumb on it until fully released?


Title: Re: Pre-loading before launch
Post by: Turbo_Rich on March 08, 2015, 23:57:34 pm
I just used to hold the button in, it was never an issue as there used to be time to reach for the gear lever! My handbrake is also well adjusted and takes close to the floor which helps