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Posted by: Dave_Darling Jul 10 2024, 12:02 AM

Some footage of a four-cylinder 914 out on track. The first corner is a bit ... scruffy, but he gathers it back up and gets going reasonably well.


https://www.youtube.com/watch?v=2Psn3k9_oek


--DD

Posted by: Geezer914 Jul 10 2024, 04:10 AM

Nice run, but I can't believe they let you drive on the track wearing shorts! Long sleeve shirt and pants should be the norm.

Posted by: Superhawk996 Jul 10 2024, 05:55 AM

Never gets old seeing a 914 pass by a tail dragger.

Posted by: Superhawk996 Jul 10 2024, 06:52 AM

Posted by: GregAmy Jul 10 2024, 07:35 AM

My favs during historics racing is when a 911 driver that I passed comes up to me in the paddock and asks what sixer I have in there.

"It's a 2L four".

<blank look>

Posted by: Artfrombama Jul 12 2024, 06:52 PM

Fast in, slow out
Slow in, fast out

Posted by: BillJ Jul 12 2024, 07:10 PM

Nice driving!

Posted by: 76-914 Jul 13 2024, 09:06 AM

I'm thinking that's not in the USA. Speedo is in Kilometers. Germany? Fun video.

Posted by: brant Jul 13 2024, 09:56 AM

I thought his suspension tune could use a little more balance and front end bite. I’m sure a historic racing in Europe limits his tire choice. But the balance can still be achieved through spring choice
Plus a bigger front anti roll bar

Posted by: brant Jul 13 2024, 09:56 AM

Duplicate

Posted by: Superhawk996 Jul 13 2024, 10:32 AM

Say what???

Typically increasing front roll stiffness either by spring or by anti roll bar will increase understeer. [note: I know you didn’t say increase front spring rate]

There may be edge cases where a bigger front anti roll bar would help decrease understeer (if car is starting with huge body roll) but not knowing anything about that particular car and its setup, I wouldn’t be proposing more front bar to help front end “bite”. Maybe we are just not using the world “bite” the same way? . When I hear bite, I hear “grip”. In the case of an oversteering vehicle, the front end has more “bite”, more grip (traction) than the rear. As a result the rear lets loose and rotates faster than the front end.

If the proposal is to add more understeer via more front roll stiffness to reduce the car’s tendency to oversteer - I’m with you 100%. All things being equal, the same effect could be achieved by reducing rear bar and/or rear spring rate.

I’m not trying to be pedantic. However I feel it’s important discussion because so many guys are thinking they need huge front anti roll bars and huge torsion bars because of what they read on these forums. Too often people just want to follow a “formula” rather than understanding vehicle dynamics.

Note: one of the hardest parts of racing is getting the whole crew using the same language and having a common understanding of the language. This post isn’t meant to disparage Brant or imply he’s wrong or doesn’t understand race car setup.

Posted by: brant Jul 13 2024, 12:14 PM

Actually i shouldn’t have been that specific

It would depend what the current spring rates, and both anti sways are currently. Plus a trip to the scales and potentially adjusting ride height or the rake

I do mean grip

Agreed he may be on the limits but still see a little push starting the corrections

I agree with softening the front

Posted by: Superhawk996 Jul 13 2024, 12:28 PM

Yeah - it’s an interesting video. Wish I had data acquisition to go with it to understand the car more.

It oversteers, it understeers, and is neutral at other times. Driving behavior has huge influence in how it shifts between these behaviors. Sometimes I see him go to the throttle and then the understeer starts as the front end unweights. Can get the opposite (oversteer) effect by abrupt lift throttle and braking while turning in.

Then there also appears to me to be some aerodynamic changes where it oversteers more at low speed but less at high speed. Likely front end lift at higher speed providing some front end lift and increased understeer behavior that prevents the oversteer at higher speed.

Again, all reasons that simply copying what works on the track may not be the best thing for the average guy driving on the street.

Thanks for understanding the intent of the previous post.

Posted by: peteinjp Jul 13 2024, 07:40 PM

I'm curious about what unsettles the car at 10:23? Is it just the tire breaking lose?

Pete

Posted by: flat4guy Jul 13 2024, 07:56 PM

Time for stickier tires and some suspension tuning. Fun to watch though.

Posted by: emerygt350 Jul 14 2024, 04:42 AM

I agree with tires, and I think he cut in a little early. Elevation change should have been in his favor.

Posted by: moto914 Jul 14 2024, 06:33 AM

@http://www.914world.com/bbs2/index.php?showuser=121
FANTASTIC !
thanks

Posted by: mlindner Jul 14 2024, 07:25 AM

Thanks for sharing Dave...But you need to heel and toe on the down shifts. Engine speeds needs to match wheel speed so rear wheels don't break loose.

Posted by: r_towle Jul 14 2024, 11:24 AM

So many ideas and comments...its great to see him out learning how to drive his car on a track...I do think the shorts is a bit much.

Rich