Cams, followers, wrist pins. Engine men please read...
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cannondale27
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- Joined: Wed Mar 10, 2021 10:41 pm
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cannondale27
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- Joined: Wed Mar 10, 2021 10:41 pm
Bringing this one back up.
As you may know Wayne did come through with the cams. Will take some pics but both Timbo and I ran these cams with only issue being from the coating on the buckets which we tried. Some coating transferred to the cam. But cams were fine.
Next step is to try Wayne's coated buckets. Yes Wayne I got them today. Can't wait to see how they work. Will be using them with one stock modified Intake cam and Waynes Exhaust Cam. This coating is definitly not the same as any we have tried before. Very shiny appearance. Hope it works. Thanks Wayne.
[attachment=7144:Waynes_Buckets_047.jpg]
As you may know Wayne did come through with the cams. Will take some pics but both Timbo and I ran these cams with only issue being from the coating on the buckets which we tried. Some coating transferred to the cam. But cams were fine.
Next step is to try Wayne's coated buckets. Yes Wayne I got them today. Can't wait to see how they work. Will be using them with one stock modified Intake cam and Waynes Exhaust Cam. This coating is definitly not the same as any we have tried before. Very shiny appearance. Hope it works. Thanks Wayne.
[attachment=7144:Waynes_Buckets_047.jpg]
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wayneschofield
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- Joined: Wed Mar 10, 2021 10:41 pm
Sorry for leaving things in the dark..... I did the 24hr race with a 996 GT3 Cup at the weekend so time up to that was used up prepping.
We were running 4th overall at 20hrs when it seems some track debris damaged the cooling system somewhere and the current driver didn't notice the alarm on the dash (everyone is very tired 20hrs into a race) and the motor fried, 190 degC coolant and 178 degC oil temp is never good! We would have been two laps clear in the lead but a broken driveshaft and a phase sensor oil leak had meant a couple of uncheduled stops.
Anyways, the followers.....
Glad they arrived, I was worried they might be lost.....
They have to be made 'shiny' with micro-finishing before the DLC is applied or else the rough (and now very hard) surface becomes essentially a file which will cut away at whatever it rubs against. Fine surface finish and the super-hard suface reduces friction, and thus heat, making life easier and cooler for the cam and followers. This combination also allows for more aggressive cam accelerations to be used before reaching the limits of the materials in use. There's much less chance of material transfer when oilling is starved too.
When a 'fresh' crank arrives back I will re-build my lad's Speed. I built his engine with the same DLC coating on the wrist pin so we will see how it has held up so far. The crank in it was badly balanced and is vibrating the thing to bits. It also had my stud/washers/k-nut arrangement so if they have done the job with a very out of balance crank then they will be fine as an 'ultimate' crank plate fix. I know 'Boomers washers 'work' but bolts into an alloy casting is plain bad engineering. If the crankplate and case are good on inspection I will have more studs made for anyone else wanting the ultimate fix.
I have ordered 50 decomp sets to be made to the new encapsulated design. The machine shop wanted a 'decent size' order to go ahead so I hope they work out, or I will be more out of pocket!
I need to go to the cam manufacturers with the desired profiles to be made as the cam design itself is different for the new decomp mech, the 'slot' for the decomp pin is radiused rather than flat bottomed and the extended end of the decomp pin anchors in the base circle of the cam lobe to keep it absolutely secure. The section of the cam that is waisted between the decomp land and the lobe is not waisted on the new design cams to give further support.
I should get time soon to modify the flywheel design so that is at least as light as stock and address the machining in the centre that was not as per the drawings.
I'll alter the flywheel sent back to me and return it to C27 for him to appoint a 'tester' for the lighter design.
I was supposed to be doing Weston beach race but time and fitness is against me, having only a week or two to build a machine and get fit, on top of working etc. The good news though is that should allow me a little time to sort the above out......
I think that's all for now....
We were running 4th overall at 20hrs when it seems some track debris damaged the cooling system somewhere and the current driver didn't notice the alarm on the dash (everyone is very tired 20hrs into a race) and the motor fried, 190 degC coolant and 178 degC oil temp is never good! We would have been two laps clear in the lead but a broken driveshaft and a phase sensor oil leak had meant a couple of uncheduled stops.
Anyways, the followers.....
Glad they arrived, I was worried they might be lost.....
They have to be made 'shiny' with micro-finishing before the DLC is applied or else the rough (and now very hard) surface becomes essentially a file which will cut away at whatever it rubs against. Fine surface finish and the super-hard suface reduces friction, and thus heat, making life easier and cooler for the cam and followers. This combination also allows for more aggressive cam accelerations to be used before reaching the limits of the materials in use. There's much less chance of material transfer when oilling is starved too.
When a 'fresh' crank arrives back I will re-build my lad's Speed. I built his engine with the same DLC coating on the wrist pin so we will see how it has held up so far. The crank in it was badly balanced and is vibrating the thing to bits. It also had my stud/washers/k-nut arrangement so if they have done the job with a very out of balance crank then they will be fine as an 'ultimate' crank plate fix. I know 'Boomers washers 'work' but bolts into an alloy casting is plain bad engineering. If the crankplate and case are good on inspection I will have more studs made for anyone else wanting the ultimate fix.
I have ordered 50 decomp sets to be made to the new encapsulated design. The machine shop wanted a 'decent size' order to go ahead so I hope they work out, or I will be more out of pocket!
I need to go to the cam manufacturers with the desired profiles to be made as the cam design itself is different for the new decomp mech, the 'slot' for the decomp pin is radiused rather than flat bottomed and the extended end of the decomp pin anchors in the base circle of the cam lobe to keep it absolutely secure. The section of the cam that is waisted between the decomp land and the lobe is not waisted on the new design cams to give further support.
I should get time soon to modify the flywheel design so that is at least as light as stock and address the machining in the centre that was not as per the drawings.
I'll alter the flywheel sent back to me and return it to C27 for him to appoint a 'tester' for the lighter design.
I was supposed to be doing Weston beach race but time and fitness is against me, having only a week or two to build a machine and get fit, on top of working etc. The good news though is that should allow me a little time to sort the above out......
I think that's all for now....
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cannondale27
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- Joined: Wed Mar 10, 2021 10:41 pm
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wayneschofield
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- Joined: Wed Mar 10, 2021 10:41 pm
I do appreciate Tim is busy all the time, I am myself through the summer and people moan that I don't answer the phone etc. The truth is though that time on the phone is time off the job, time we can't afford to just give away.
I also understand that cashflow can be the cause of lots of stress and problems and that the 'quick turnaround' jobs tend to get prioritised over the long-haul jobs to keep the cash flow in through the door (it certainly flows out of it fast enough). That's the reason I sent him a good chunk of cash up front when he was having trouble getting paid from some quarters.
It would be very helpful to have at least two stock cranks for now so I can do some updating of motors.
Cheers Steve.
I also understand that cashflow can be the cause of lots of stress and problems and that the 'quick turnaround' jobs tend to get prioritised over the long-haul jobs to keep the cash flow in through the door (it certainly flows out of it fast enough). That's the reason I sent him a good chunk of cash up front when he was having trouble getting paid from some quarters.
It would be very helpful to have at least two stock cranks for now so I can do some updating of motors.
Cheers Steve.
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cannondale27
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- Joined: Wed Mar 10, 2021 10:41 pm
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wayneschofield
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- Joined: Wed Mar 10, 2021 10:41 pm
Cheers.
I just paid Wistech for a crank in case I need it to get a motor together.
My 14 year old son Luke is on with building a new chassis, he was the one in line to get the short stroke motor but, since he's grown quite a bit lately he can probably manage a proper size lump now. Part of the plan was to do him a 'soft' motor that would last really well which I could still do with a 432 I guess.
I just paid Wistech for a crank in case I need it to get a motor together.
My 14 year old son Luke is on with building a new chassis, he was the one in line to get the short stroke motor but, since he's grown quite a bit lately he can probably manage a proper size lump now. Part of the plan was to do him a 'soft' motor that would last really well which I could still do with a 432 I guess.
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wayneschofield
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- Joined: Wed Mar 10, 2021 10:41 pm
The thinking behind short-stroke was less torsional vibration, lower comp with stock piston (by default since less swept vol) and less punch from the motor that might have him flipping it etc since he's light and over-eager. Shorter intake cam would be employed with later timing, 110 maybe to lose some mid range and help with stalling.
Cheers.
Cheers.