I have purchased a set of digital scales and am adjusting the corner balance on my circut car and need some technical info to help me with the set-up . Can someone that has some experience in this help me with some info or point me in the right direction .
I have set the car on the scales and the total weight is 749 kg's . I have scaled it as it came off the track at Wakefield park , and than adjusted it to what I feel is good . I have all 4 corners independantly adjustable and can get an even amount of weight on each corner . The problem is that the car looks all twisted and bent . I have gone the other way now and set the ride height to where I want it and now the corner weights are now all unevan . I have 100 kg's of weight in the drivers seat and am now moving such things as the battery to different positions in the car to even up the weights .
I have ended up with 48% of the total weight on the left side and 52% on the right . I now also have 37% of the total weight on the front wheels and 63% on the rear . I am happy with what I have done for now but dont know if it is the corect way of doing it . I am back at Wakefield park on the 6th of December and if it handles like a bag of shit I know what I can adjust to transfer more weight to another part of the car . Some experienced help would be good , thanks ROD.
More boost + More fuel = More power
1968 Beetle fastest run 8.96 sec @ 161 mph 4th Nov. 2001
2010 New Beetle 8.12 sec on 8th march 2014 http://www.rodpenroseracing.com.au
This is a lot of fun getting it right 🙂 Seriously it makes an enormous difference once you have it correct-You can even get to make minor adjustments for different circuits as you may already do with tyre pressures , sway bars and shocks.
Few articles here that may help.
Rod, I've been thinking about the corner-weight readings that you have been getting. The front anti-roll bar may be influencing the figures. I know that it cannot be dis-connected for corner-weight adjustments (normal race car practice), so David - my son - and I will try to work out a way to do adjustments with the roll bar in the normal situation. Will be in touch after Philip Island.
Cheers, Greg
I'd rather wear a Beetle out by racing it than by polishing it!
good stuff rod when i was ayoung fella working on sport sedans corner weighting was one of the best tuning tools we had, we made great gains. make sure your body double is basicly the same shape as you as this does make a diffrence also your not gunna get close to 50/50 without adding weight most 70's race porsche had about 40/60 front to rear, have you moved the gearbox forward any? do you remember what your tyre temps were from wakefield cause if the fronts are getting hot enough you may want to make very small adjustments as not to undo what is a good baseline to work from. ill ring ya this week some time and get some parts and have a chat!
Is the body double before or after lunch? As Greg said the front swaybar will be playing a part in all this, maybe adjust the front springs like a valve spring so that each is equal side to side, then do all the adjusting on the back end.
Ok just had a thought, maybe unworkable. On the front corner weight a solid fixed point each side of the car so that you get the car balanced side 2 side, then with those two fixed points corner weight the rear end, as I said this maybe unworkable.
Good day Rod-settled back to normal yet.Geez missing Dennys.Could you send me Michaels email and phone number when you get a chance.The Mustang and my parts left Able Cargo last Friday.
I played with corner weights on my tube framed car and found that the anti roll bar was the biggest influence.
Although mine was only on the rear.
I disconnected the anti roll bar link at first.
I used the coil over shock 'spring base' to set the car level with me in the seat,
and then any drastic error was improved with slight preload of the anti roll bar.
Trying to make it perfect in a static situation was no good, with engine torque unloading the rear suspension,
but moving weight around made the bst improvements,(30kg ballast, 10kg battery and 20kg fue tank).
If the ground is not level that will make a huge difference.
All the books I have claim the corner weight should be set with anti roll bars disconnected
and adjust them at the track.
gday Rod dont forget to check that your rear torsion bars are set at the same height jack the front of the car up in the centre ,then measure the rear at the torsion mounts to the ground if these are different, must be set first otherwise big weight transfer problems,will upset all your readings, cheers Rudi
Thanks for the reply's . I have done all what you have suggested with the exception of the front sway bar disconnection . This is a little tricky as it holds the front suspension in the correct place , so I will try to mount the front sway bar in the centre and see if this makes a difference . I also like the idea of the tripod theory if I can get a mount directly in the centre of the front . This is only a starting point for me and I need a base line in which to start from and improve it from there . I am also toying with the idea of removing the 26mm torsion bar from the right hand side only and replace it with a 27mm bar to compensate for the driver { before lunch } . I also have 275lb springs in the front and may go up to a 300 lb on the drivers side as well . I will scale it up again this weekend and see what it will do . I will also alter the thickness of the spacers on the wheels as this will alter the weights , but will also alter the track , ROD.
More boost + More fuel = More power
1968 Beetle fastest run 8.96 sec @ 161 mph 4th Nov. 2001
2010 New Beetle 8.12 sec on 8th march 2014 http://www.rodpenroseracing.com.au
Rod, go back to a zero adjustment....u need to take one wheel of at a time
adjust small amounts......
u will need to do this all for corners until right....
no adjustment on ur coilovers will be the same.....
rod why not make up 2 drag links that u can replace the sway bar with, then just tie up your sway bar in the approx place till you've finnished. make the links the same weight then subtract the percentage change from front to rear bias.
Daimo , I made it to the MX5 day and killed the engine on the first run . I had reset the suspension on the corner jacks and changed the oil to a heavier grade to boost the low oil pressure at the end of each run . I was concerned about the 10 psi of pressure at 115 degrees and decided to go for a heavier , thicker oil to prevent the oil breakdown .
On the first outing the oil temp was around 80 deg C as I left the pits , and after the 2nd lap I switched the fan on to operate the external cooler as the temp had got to 120 deg. . By lap 3 the oil was pushing 135 deg. and half way around the 4th lap it reached 150 deg. . I decided to back off and drove around at 3000 rpm's as this was the last lap . By the time I arrived back in the pits the engine developed a knocking sound . After letting the engine cool down , the crank pulley was wobbling all over the place and I thought that I had broken the crank .
I have stripped the engine and the # 2 conrod bearing is no longer there . The engine and cooler system holds almost 6 litres of oil and there was no issue with oil surging . I also have 1mm of sideways clearance across the lifter bores and 3mm of vertical clearance . I think that the engine was so hot that the magnesium has soften and gone all out of shape . The crank, rods , case and piston/barells are all stuffed . I have now built a 2276cc engine with all new components , the same fk46 cam and lifters , raised the comp. to 10.4 and changed to a set of superflo's and some 48mm IDA's . I will dyno this combo on Thurs/Fri this week and will run the car this weekend at Marulan with all of the other vw's , ROD.
More boost + More fuel = More power
1968 Beetle fastest run 8.96 sec @ 161 mph 4th Nov. 2001
2010 New Beetle 8.12 sec on 8th march 2014 http://www.rodpenroseracing.com.au
Heavy grade oil can cause over-heating, as I found out at Winton a couple of years ago Rod. As you will be at Marulan on Saturday, I'll explain why a lighter oil reduced the oil temp. Is your engine dry-sumped? If so, this can also cause high crankcase temps. See you on Saturday.
Cheers, Greg
I'd rather wear a Beetle out by racing it than by polishing it!
Hope the new combo goes well for you Rod.
I had also heard the same thing about heavier grade oil not cooling as well.
Look forward to hearing of it all.
I ran my 1998 11/1 well past 140c 7500rpm for three seasons everythings still fine, floged out lifters and bores possible too hi valve seat pressures.what type of oil you using, a good 15w/40 turbo oil should be fine,have heard of cam follower bores flogging out before on mag cases,dont muck around use an alloy case, Also check condition of camshaft thrustbearings,have had a few of these look pretty ordinary as well may have lost drive on oil pump.How many are heading to Marulan on the weekend.
RodPenrose wrote:Daimo , I made it to the MX5 day and killed the engine on the first run . I had reset the suspension on the corner jacks and changed the oil to a heavier grade to boost the low oil pressure at the end of each run . I was concerned about the 10 psi of pressure at 115 degrees and decided to go for a heavier , thicker oil to prevent the oil breakdown .
On the first outing the oil temp was around 80 deg C as I left the pits , and after the 2nd lap I switched the fan on to operate the external cooler as the temp had got to 120 deg. . By lap 3 the oil was pushing 135 deg. and half way around the 4th lap it reached 150 deg. . I decided to back off and drove around at 3000 rpm's as this was the last lap . By the time I arrived back in the pits the engine developed a knocking sound . After letting the engine cool down , the crank pulley was wobbling all over the place and I thought that I had broken the crank .
I have stripped the engine and the # 2 conrod bearing is no longer there . The engine and cooler system holds almost 6 litres of oil and there was no issue with oil surging . I also have 1mm of sideways clearance across the lifter bores and 3mm of vertical clearance . I think that the engine was so hot that the magnesium has soften and gone all out of shape . The crank, rods , case and piston/barells are all stuffed . I have now built a 2276cc engine with all new components , the same fk46 cam and lifters , riased the comp. to 10.4 and changed to a set of superflo's and some 48mm IDA's . I will dyno this combo on Thurs/Fri this week and will run the car this weekend at Marulan with all of the other vw's , ROD.
'56 Beetle, 1916
Craig Torrens6 times Australian, 7 times State Hillclimb Class Champion
RodPenrose wrote:Daimo , I made it to the MX5 day and killed the engine on the first run . I had reset the suspension on the corner jacks and changed the oil to a heavier grade to boost the low oil pressure at the end of each run . I was concerned about the 10 psi of pressure at 115 degrees and decided to go for a heavier , thicker oil to prevent the oil breakdown .
On the first outing the oil temp was around 80 deg C as I left the pits , and after the 2nd lap I switched the fan on to operate the external cooler as the temp had got to 120 deg. . By lap 3 the oil was pushing 135 deg. and half way around the 4th lap it reached 150 deg. . I decided to back off and drove around at 3000 rpm's as this was the last lap . By the time I arrived back in the pits the engine developed a knocking sound . After letting the engine cool down , the crank pulley was wobbling all over the place and I thought that I had broken the crank .
I have stripped the engine and the # 2 conrod bearing is no longer there . The engine and cooler system holds almost 6 litres of oil and there was no issue with oil surging . I also have 1mm of sideways clearance across the lifter bores and 3mm of vertical clearance . I think that the engine was so hot that the magnesium has soften and gone all out of shape . The crank, rods , case and piston/barells are all stuffed . I have now built a 2276cc engine with all new components , the same fk46 cam and lifters , riased the comp. to 10.4 and changed to a set of superflo's and some 48mm IDA's . I will dyno this combo on Thurs/Fri this week and will run the car this weekend at Marulan with all of the other vw's , ROD.
