World Formula?

[Corey Poynor]

Has anyone else been seeing a variation in the piston out of the hole dimension on these engines from the factory? We have had them everywhere from .023 to .041 in recent years. The last batch we received had anywhere from .029 to .038. We are measuring it just as the IKF rules state, with a tool steel bar and a dial indicator over the center of the piston parallel with the wrist pin.
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Poynor/Dean Racing Engines and karting supplies
www.pdrekarting.com

[Mike Burris]

Corey, I heard there is a gag order on responding to your post!

[Dean Graves]

The gag order has been lifted @ Bobs 4cycle.

[Corey Poynor]

The numbers do not lie. Reading a micrometer or a dial indicator is what I do for a living.. Gag order or not, I find it interesting that we are the only ones asking about this. We have had the same problem for several years now with nothing being done to change it. We have talked to Dave Klaus and he has next day aired us blocks that should fix it. Those blocks only made a .001 difference. We have measured the rods, stroke, compression height, and crank pin diameter and they are all well within the spec. Therefore, that tells me they (Briggs) have a machining issue with the deck dimension to crank centerline on their blocks.

All we would like to see is some resemblance of consistency and stay within the rules as written.

Enough of this crappolla, I'm going to watch the race..

Later
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Poynor/Dean Racing Engines and karting supplies
www.pdrekarting.com

[Ryan Knowlton]

Ick, that much variance on an engine that is 12x the price of a clone?
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03 Italkart Supersonic V
420cc Predator Clone

[John Matthews]

Perhaps Briggs should go to the LO206 manufacturing process for all it's engines?

I would speculate that blocks not within certain tolerances are used for Animal and World Formula production since these engines are normally blueprinted by builders, or just raced straight out of the box like they do at some clubs. Unfortunately for US sprint karting, sealed box stock World Formula racing has only caught on in a few places (like the whole World Formula platform). I happen to think that running them straight as they come from Briggs makes a lot of sense, but when you start blueprinting them you're really competing with the KT100/KPV in terms of cost and power. With a heavier package this makes it a hard sell in a lot of clubs. The places that run them really do like them, but when everyone is trying to get the last .05% of HP it makes the prices go up. I've only had one Duffy winning World Formula customer, but if I was trying to build a bunch of them to that level I would probably be buying LO206 short blocks for my parts sorting program....

The market has spoken with 4 stroke and Briggs is trying to keep up with LO206 production since that's where most of the orders are. If you find excess variance in World Formula it's probably because of that, overnight shipping of replacement parts at no charge is going above and beyond in my book

Cheers,
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John Matthews
Heartbeat Power, LLC.

[Corey Poynor]

Shipping blocks to us was cool, never questioned that. Lack of consistency is what the concern is and has been.

As for racing them out of the box, this last 5 had 1.1 hp and .9 tq difference between the best and worst. And the dimensions showed us where that was from.. That is why we don't speculate, we measure and test.
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Poynor/Dean Racing Engines and karting supplies
www.pdrekarting.com

[John Matthews]

Never meant to say there isn't power in blueprinting these motors, Luke Pascoe can probably testify to that for me

You're in one of a few pockets where World Formula has taken off, Southern California is another one but I'm not aware of too many others in the states.

There are a few programs out there that seal World Formulas but they're pretty spread out too. If the World Formula had been widely accepted in the US we might be looking at a program similar to the LO206 where tighter consistency is ensured through manufacturing processes. Briggs Racing has demonstrated it's possible now but pretty much all World Formula racers fall into one of two categories that don't really need it. Either they're recreational karters who just want an electric start, low maintenance engine with enough power to have fun on a sprint track. Or, they're running a series where they buy their engines from a builder or do the blueprinting work themselves.

Briggs has kept the World Formula pricing pretty much the same since I became a motorsports dealer in 2005, at least that part is consistent

Seriously though, if there's an increase in pop-up variance it's probably because of the LO206 program. They can't be expected to throw away perfectly good blocks for the variances you've noticed, it does make a difference but that's what racers pay a builder for anyway isn't it?

Cheers,
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John Matthews
Heartbeat Power, LLC.

[Corey Poynor]

Maybe I am not understanding, .018 variance overall and .009 in just this batch is not enough to make someone say HUH!? .005 sure as heck would make us take a second look at something in our shop!

So you are telling me that an engine that is roughly a $1000.00 is getting the hand me downs/throw aways from an engine that is roughly $550.00? Why don't they just send them over to the mower or tiller shop? Or better yet, set the machines up to work off the centerline of the crank bore and cut less material off the deck... Instead, we the shops and racers have to weed through and hope we get one that is within the spec of the IKF and or WKA rules.

You cannot tell me we are the only ones seeing this issue.. And by the calls and emails we have received, it is true, we are not the only ones noticing. We have been getting some flack from some WF supporters, and even though they are in full support of Briggs and the WF program, they too understand and see the issue and would like to see it fixed.
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Poynor/Dean Racing Engines and karting supplies
www.pdrekarting.com

[David Klaus]

I thought I would respond to Cory's post. He was included on a recent e-mail sent to the IKF tech committee concerning pop-up after raising concerns on the subject.

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The WF was released in 2003 and the potential piston pop-up from the first engine to the one we built yesterday has not changed. This was and has been expressed to both IKF, WKA and Kidsprint for that matter. It’s homologated right into the international rule set created in 2003. This maximum piston pop-up is .035”. This is across the center of the pin. This does not take into account the method used in the field of laying a bar stock across of a domed piston that has a 1 degree draft angle. I think everyone is aware that the part number can also displace material on which the bar is placed adding artificially to the popup.
The history for IKF's .020” I know because I was a part of it. It was chosen at the time to keep the rule as close to what was seen at that time. I don’t disagree with that method but I expressed my concerns and the potential of Corey’s remark below we have today. It’s time to change your rule to account for our manufacturing tolerance.
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Cory is a perfect example on why we actively work with organziations to prevent. We have a known tolerance and this is not reflected in the rule set. This tolerance has been known, openly expressed to every sanctioning body, and anyone that wants to contact us including Cory.

I did send Cory cylinders and I think I sent them next day air to help him out the week leading into the Grands. These were to replace cylinders on engines that were within our manufacturing specifications but not to IKF's choosen pop-up spec.

Imagine a manufacturer going above and beyond to help out even though this wasn't a manufacturing issue? That's what we did.

[Corey Poynor]

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Poynor/Dean Racing Engines and karting supplies
www.pdrekarting.com

[Corey Poynor]

[quote="Corey Poynor"]Shipping blocks to us was cool, never questioned that. Lack of consistency is what the concern is and has been.
quote]

You are right dave, you did send us new blocks, and they measured a whole .001 better than the ones that were .041 out of the hole..

This was not intended to be a briggs bashing question or post, just a question to the rest of the builders and racers.. You can take it how you like now.


You are also correct that I was included in the email with the IKF tech committee, as I was the one that asked the original question of them.. And I also did as I was asked and took pictures of the barcodes and the dimensions and emailed them to the head of the committee and you.. I can post all of them on here if you would like, but for now I am going to only post what I said and the response I received from yours truly...

"I should probably give you all some more info on this issue we are seeing.
We received these engines, checked the valve lash, added oil (red-e) and ran them on the Dyno. Our Dyno is a Land and Sea water brake with all of the latest software, a flow meter, weather station, oil temp, EGT, and Cylinder head temp. We run them for a total of a half our. We warm them up to 100 degree's oil temp and make 2 pulls. We shut them off, close the valves and cool them totally off with a fan blowing on them. We then warm them up again and make three hard pulls, drain the oil, and disassemble and measure them. At that point, we found one at .029 pop-up (which can be made legal by the time we clearance everything and sand the top of the piston a little), two of them were at .033, one was at .035 and one at .038.. Rod length, compression height and stroke are all well within the legal limit. We did run into a similar problem in 2010 also, and at that time Dave did send us new blocks. Unfortunately the new blocks had the same issue as the originals..



Any input would be appreciated.

Thank you

Corey "

In the middle here, there was another email from an IKF 4 cycle tech committee person stating that they have had the same problem with variances since 2005 and maybe we should change the rule again. (for the 4th time)

My response

"Changing a rule to suit an inability to be consistent as a manufacturer is not the answer, none of the other manufacturers are allowed that courtesy.. But that is a whole other story and I will refrain for now.. As for sanding the piston, I have been told several times that if the block still has the factory machine marks on the deck surface, you can sand the piston top as long as you can still see the numbers and arrow. If this is changed, please let me know.

Corey"

From Mr. Klaus

"
I’ll start by saying it’s great to have everyone involved in the process this time around. I think Corey’s misguided response below is the exact reason why we work with organizations whenever possible to try to avoid. The WF was released in 2003 and the potential piston pop-up from the first engine to the one we built yesterday has not changed. This was and has been expressed to both IKF, WKA and Kidsprint for that matter. It’s homologated right into the FIA international rule set created in 2003. This maximum piston pop-up is .035”. This is across the center of the pin. This does not take into account the method used in the field of laying a bar stock across of a domed piston that has a 1 degree draft angle. I think everyone is aware that the part number can also displace material on which the bar is placed adding artificially to the popup.

The history for the .020” I know because I was a part of it. It was chosen at the time to keep the rule as close to what was seen at that time. I don’t disagree with that method but I expressed my concerns and the potential of Corey’s remark below we have today. It’s time to change your rule to account for our manufacturing tolerance.



More of an FYI but in the future our pistons will have the etching moved to try and accommodate for your method of field testing.



If any of you have any other questions that is why we are here.



Best regards,

Dave"

With all of this said, I am not quite sure where I am "misguided". I did ask you and the tech man the question and some of the guys on the committee had the same problems we have. My "remark" is spot on and a FACT that everyone knows. Having rules that are a living document does not do anyone any good except the manufacturer...$$$$$ out of our pockets.

Your statement in other emails of the parts being within "industrial tolerances" is not even acceptable as you are claiming these to be "racing engines" not industrial engines..

"It’s time to change your rule to account for our manufacturing tolerance."
Maybe it's time you fix your manufacturing tolerance to fit the rules set forth..
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Poynor/Dean Racing Engines and karting supplies
www.pdrekarting.com

[John Matthews]

I bet Briggs would be happy to change their manufacturing spec if someone placed a sufficient order to cover the costs

I'm sure as a kart engine builder Corey has some idea of the size market we're talking about. I'm also sure he has an understanding of the nature of karting organization rules committees

I don't run a manufacturing business so I can't comment on whether or not Briggs tolerances are reasonable for this engine but if they've been the same since 2003 and IKF chooses to use tighter tolerances and different measuring techniques I can only speculate there's somebody on the rules committee that wants it that way for a reason.

I do however build race engines and am fully aware of the investment in parts stock required to build really good "legal" engines. Parts sorting is the name of the game in every spec engine class, at least four cycle parts are cheaper and more forgiving of a thousandth here or there. Go buy a new KT100 or Leopard and see what you're up against for blueprinting

As for the guy who brought up clones what planet is he on? Talk about tolerances Briggs took care of potential flywheel issues, changed the ignition system to one that can't be cheated, and improved just about every part on the World Formula while maintaining the original specs and didn't raise the price

JMHO,
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John Matthews
Heartbeat Power, LLC.

[David Klaus]

Cory, You are the perfect example for why we want rule sets to meet our manufacturing tolerances along with a better testing method. Your issue is with your sanctioning body and yet your 'dig' is directed at the manufacturer? A manufacturer that helped you out by sending out good parts in addition to the good parts you kept. Frankly it's disappointing to see how you are acting on every level.

Cory you have a choice what you sell and don't sell. If our products disappoint you feel free to take a different path. I'm perfectly fine with that. The amount of WF engines sold to date and the track record of the product speaks for itself.

If those cylinders didn't help feel free to send them back. You know how to get ahold of me.

Take care.

[Corey Poynor]

Dave,

Can you point out the CIK homologation specs for pop-up in this, I can't seem to find it.

Thanks
Corey

https://docs.google.com/viewer?a=v&q=cache:2gKC6nuiwzEJ:www.haks.hr/pravilnici/karting/11k-teh_prilog5.pdf+CIK+FIA+WORLD+FORMULA+BRIGGS&hl=en&gl=us&pid=bl&srcid=ADGEEShSWqrCvmQ0x1Xfg2hTzfP9rB-XBDPXi8FrIZQNiunuevBtoOTV4rBUvDvUt32bAmng1zOqVmj2rM5jofkyPSjjmCdZAfj9aM5tIY55LUI9plHcEduqcvD5cyGt6ivkCIbonnej&sig=AHIEtbQhQROHYQY-vLjA0_9uuFFaLnzOlw
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Poynor/Dean Racing Engines and karting supplies
www.pdrekarting.com