The reason the bars have heim joints is so that you can change the IC without ruining the pinion angle

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Originally posted by Bucky:

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Originally posted by racerdude2054:

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Originally posted by Bucky:

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Originally posted by racerdude2054:
The below is quoted from Luke Bogacki on September 23rd 2016 in regards to the CV drive shaft and why he chose to use it.

“• A big reason I wanted to switch to the CVD on Jessica’s car is that I typically run a lot of pinion angle on a more underpowered car like this (her car runs 4.90’s) to help the motor drive the tire into the ground down track. I mean a lot of pinion angle. Like, I have to keep an eye on u-joints pinion angle. With the CVD, I’m essentially unlimited on pinion angle; where a typical u-joint will start to wear and fail if it’s in a bind, the CVD offers constant velocity at any angle.”

I respect Luke's experience and knowledge. But we are applying downward force to the rear end from the driveshaft? No? Then what affect is the pinion angle having on "driving the tire down to the ground down track"? What would cause this? From an engineering stand point, this makes little sense. He can do whatever works for him, and he obviously sees a lot of success. But this doesn't make sense to me.

Could the 4-link setup not place the rear-ends pinion facing down into the track, resulting in a lot of pinion angle?

What is the advantage of that?

I think what he might be doing is setting the suspension up to have a lot of extension. If the suspension extends a big amount (even with a 4 link) the pinion angle can change enough to cause the pinion to run with the wrong angle (pointed up in relation to the crank angle). Can't say I agree with this method but not gonna argue that it works for him. If set up like this a person better have a shock or shocks with really good dampening.

Scott

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I think what he might be doing is setting the suspension up to have a lot of extension. If the suspension extends a big amount (even with a 4 link) the pinion angle can change enough to cause the pinion to run with the wrong angle (pointed up in relation to the crank angle). Can't say I agree with this method but not gonna argue that it works for him. If set up like this a person better have a shock or shocks with really good dampening.

The beauty of the four link design is that the pinion angle changes little within any regular working range. I have seen cars that played with big extension, on dragsters, and it never seemed to be a good all around setup.

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Originally posted by Bucky:

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I think what he might be doing is setting the suspension up to have a lot of extension. If the suspension extends a big amount (even with a 4 link) the pinion angle can change enough to cause the pinion to run with the wrong angle (pointed up in relation to the crank angle). Can't say I agree with this method but not gonna argue that it works for him. If set up like this a person better have a shock or shocks with really good dampening.

The beauty of the four link design is that the pinion angle changes little within any regular working range. I have seen cars that played with big extension, on dragsters, and it never seemed to be a good all around setup.

Luke has rented out tracks and experimented with 4 link changes on 60 foot hits for 12 hours at a time. The super comp world champion, multi time national event winner, and million dollar race winner says pinion angle adjustments work for him and its hard to deny the success he has had

I have talked to Luke and also called some dragster fabricators who have all stated they have had seen improvement with a pinion angle of 1 to 4 degrees with the rear yolk pointing downwards. 1 to 4 degrees depending on the horsepower of the car (just as luke said)

That said, I saw personal improvements in overall consistency by going to 2 degrees

People may choose to disagree, but based on personal experience I truly do believe it made a difference. Or, it could just be in my head. Regardless I will continue to believe it has made a difference

Hey that's the beauty of drag racing. You can experiment all you want and run it the way you find that works!

Luke could convince a lot of people to believe a lot of things just because of the success he has had. Not saying what he says isn’t true.

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Originally posted by green1:
Luke could convince a lot of people to believe a lot of things just because of the success he has had. Not saying what he says isn’t true.

Ditto

every dragster chassis builder will tell you that pinion angle has nothing to do with better bite/traction/hit.

End of discussion!

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Originally posted by 1320racer:
every dragster chassis builder will tell you that pinion angle has nothing to do with better bite/traction/hit.

End of discussion!

I guess the ones that I spoke to don't count, and I'm guessing you called every chassis builder there is to therefore include "every dragster chassis builder" in your statement

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Originally posted by green1:
Luke could convince a lot of people to believe a lot of things just because of the success he has had. Not saying what he says isn’t true.

I haven't seen Luke post on here nearly as often as he used to. It's probably because all the people who are much smarter than him ran him off

Question. Has anyone seen a change in car performance or consistency with change of pinion angle? Just wondering.

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Originally posted by wideopen231:
Question. Has anyone seen a change in car performance or consistency with change of pinion angle? Just wondering.

As stated on this thread. Yes, I have.

As Luke stated in his facebook video that I linked. Yes, He has

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Originally posted by 1320racer:
every dragster chassis builder will tell you that pinion angle has nothing to do with better bite/traction/hit.

End of discussion!

Give Jerry Bickel or Tim McAmis a call today and ask them if pinion angle can make any fine tuning changes on the bite

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Originally posted by racerdude2054:

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Originally posted by wideopen231:
Question. Has anyone seen a change in car performance or consistency with change of pinion angle? Just wondering.

As stated on this thread. Yes, I have.

CLUELESS^^^

I'm am no means an expert on this.

It's all about driveshaft/u joint alignment and not pinion angle. Even the best have changed their minds on this subject in the last few years and almost all agree, pinion angle has nothing to do with how hard a car hits the tires. Even Dave Morgan has said such. (I include him by name because that is who everyone seems to quote for the last 15+ years)

Watch this video on u-joint velocity and how it changes with driveshaft alignment. Tell me how adding "pinion angle" will help a car hook.

https://www.youtube.com/watch?v=gmV4qwLfOMY

It's quite simple (to me), if the car responds to an angle change, you had the u-joints in a bind previously. Add more and go to far, you are back to binding.

You want to change the chassis, you need to change the bars, ride height, shock or torsion bar setting, etc. "Pinion angle" makes a difference because of the movement of the rear housing. We call it pinion angle because in order to change the alignment, you need to move the pinion up or down. The car responds to better alignment and people assume its "pinion angle" that was the cure.

Dave Morgan was clueless when he wrote that book 25 years ago and still is today.

Yep, but everyone still quotes him for some reason.

The clueless. Same clueless that think David Vizard knows.

If there is an effect of pushing the rear down by using the driveshaft as a lever.....do you really want to be part of that method? If the car needs more bite, there are half a dozen suspension adjustments you can make to achieve that. None of those adjustments rely on the driveshaft to help plant the tire.
Again, if folks have good results with it, that is great for them. But I think I am going to be nice to my plain ol driveshaft with regular joints. Everyone can make their own choice.

The problem is, those in the know need to educate those who still think old school instead of treating them like idiots.

I had the same problem when I didn't understand. My buddy, a chassis builder, treated me like an idiot, well anyway, I told him "time out, please educate me so I understand." At this point he sat down and took the time to explain it to me. Then, over time, I started to understand it better as I worked on many different cars and set ups.

When you tell someone they are wrong or clueless, the feel the need to defend themselves and the message is lost. It's all in the delivery.