1600 Engine Build

There should be no clutch slippage under max torque. This problem might improve as the clutch disc and friction surfaces get happy together, but it might not. Resolution of this problem might require a pressure plate with higher clamp force. If the pressure plate is stock there might be too much torque from this engine for the stock pressure plate to resist slipping.

Kevlar friction disc are quite durable with smooth engagement.


Bernice


Part 3

The clutch was not broken it and slipping under full load, so I am not sure we got the maximum. Here is the outcome of the session:

Paul Davock
 
There should be no clutch slippage under max torque. This problem might improve as the clutch disc and friction surfaces get happy together, but it might not. Resolution of this problem might require a pressure plate with higher clamp force. If the pressure plate is stock there might be too much torque from this engine for the stock pressure plate to resist slipping.

Kevlar friction disc are quite durable with smooth engagement.


Bernice

Indeed, the clutch was new when the dyno work was done. It has improved and now it is smooth and has shown no signs of slippage. I am using the pressure plate that Superior Friction supplied with the clutch.

What is your experience with solid mounts and stress cracking? The mounts are very robust; I worry about the rest of the car.

Paul
 
Hi Paul, I enjoyed reading about your build. With respect to the NACA duct, can you share what you learned about their construction for effectiveness? I am also going to make some for my build and they will probably be dimensionally similar. On a separate note, I appreciate your application of the CBR600 intakes and your desire to make the most mid-range power/torque for your engine. I have a background in motorcycles and came across an interesting modification in the VFR forum. Perhaps it could allow you to shorten your intake and get rid of your solid engine mounts. Interesting reading regardless.
http://www.vfrdiscussion.com/index.php?/forums/topic/80640-yoshi-style-velocity-stacks/
 
I drove on the street a season with a solid engine mount (dog bone) and solid transmission/engine mount. The side engine mount was stock. I also had coil-over suspension with no rubber on the top mount. You could feel driving over any small rocks.

it didn't felt that bad. To be honest, I'm the kind of guy who can enjoy driving a race car to work in traffic, so you may have to take my opinion with a grain of salt. I have to admit, after a few thousand miles, I started loosing all nuts that weren't correctly torqued. In fact, part of my exhaust and a halfshaft falled on the road.

Didn't noticed any stress craks but a season was not probably long enough to create stress problems on the body. The car is in storage/restoration since then.

Driving with a solid engine mount is interesting cause there won't be any back and forth motion of the engine when accelerating or changing gears, so reaction are really quick. It is even more noticeable than switching to a lightweight pressure plate (that I did previously).

Those who drove my car agreed it was still street driveable and got quicker reactions.
 
Hi Paul, I enjoyed reading about your build. With respect to the NACA duct, can you share what you learned about their construction for effectiveness?

Here is the source:

https://digital.library.unt.edu/ark:/67531/metadc65007/m1/

Way more than I wanted to know, and math that was beyond me. But it can point you in the right direction.

If you decide to buy them, go to an aircraft supplier, such as Aircraft Spruce.

For a different size than they offered, I contacted the supplier of the duct I liked.

Paul
 
I thought I would compare Pauls 1600 chassis dyno curve to my 1500 from 2009. I think this is an excellent example of what two different engine builds will yield. I biased everything to high rpm horsepower for the track and Paul focused on max torque. The builds are so different but it is certainly cool to compare and contrast the info. If anyone sees any errors let me know, I ran through the data fairly quickly. Thanks Paul for posting the dyno info.

From the data available:
1600
Avg HP = 81.11
Avg Torque = 90.58

1500
Avg HP = 77.43
Avg Torque = 69.78
NOTE: The data was extracted and not provided so look at everything as an estimate
NOTE: The 1600 and 1500 were not run on the same dyno




Slide1.JPG



Slide2.JPG
 
Paul's screenshot says "Flywheel hp" and "Flywheel torque".
Is that really what it is?

The differences to the numbers of the engine dyno are pretty large, aren't they?
 
ULIX! Greetings my friend! Yeah both good questions for sure. It has always been a rule of thumb around the local dynos that the loss through the drivetrain is 17-22% so I normally use 20% because it is easy to calc with. Thumb in the air calc from the engine dyno is peak of 122hp and as loss of 20% is about 98hp. This is just slightly higher than Pauls peak chassis dyno power of 95hp that was estimated from the graph. Considering factors of error etc it passes the smell test but yes lots of assumptions too. For the chassis dyno the numbers are consistent with WHP numbers even though it says flywheel so I took the leap of faith and assumed they meant WHP. I cant remember a dyno sheet that did not have some erroneous info of some sort on it. Just the same probably warrants a quick call to the dyno guy to confirm what he is really measuring.
 
I stopped summing up the cost when I realized that knowing the total would be a big interference with my pleasure in the process. The build was spread across a number of years, so this was easy to do. Sorry, I don't know the total.

I too worry about stress cracking. Today I was under the car adjusting the shifter, and I was looking for any disturbed paint in suspicious places.

You know, we live close to each other, I am in Kitchener. When the salt is off the roads we should check out each other's rides. Alas, that will be quite a while from now.

Paul
Ya, a few months before I get the car on the road again. Let's plan to hook up then.

Thanks.

TonyK.

Grimsby Ontario Canada
 
Paul's screenshot says "Flywheel hp" and "Flywheel torque".
Is that really what it is?

The differences to the numbers of the engine dyno are pretty large, aren't they?

Yes they are. The screen shot of the chassey dino must be wheel HP. It makes no sense otherwise. This would have to be around 70 wheel HP, and it drives too well for that, and the difference is huge for both being flywheel HP.I suspect that the brand new slipping clutch may have reduced the numbers slightly, he did have to turn down the dino resistance part way through the run but...

I never read the fine print on the screen shot and always assumed it was wheel horsepower.

I know my builder used a fully calibrated engine dino. I trust those numbers.

The tune is good from the wheel dino, and that is what I really wanted.

Paul
 
I remember Miller's Mule very well. When I had my first X (many years ago) he was still in business and he offered many very nice products. More recently when the current X come to my possession I went straight for his site, but he was gone. I'd love to have several of the parts he made...or even good reference materials to them (guess I did not save any of the data). I'd appreciate seeing your other crank pulley set-up. Also any pictures to illustrate the cam trigger tooth arrangement. Thanks

Sorry for the delay in responding, I had to take pictures.

I took the timing cover off so you could see the cam sensor and tooth. The tooth was made from a shaped bolt threaded into the pulley.

Here is the Piper adjustable cam pulley:

DSC_0157.jpg


And the Hall sensor with the tooth passing it

DSC_0159.jpg


I have three pix of the cast iron Millers Mule pulley and trigger wheel that I did not use. I wanted to reduce the rotating mass as much as possible, and used an aluminum one.

DSC_0166.jpg


DSC_0167.jpg


DSC_0168.jpg


Paul
 
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Thank you Paul. Very nice pictures, I appreciate seeing them. The bolt as a trigger point is simple and effective. Could be adapted to any pulley.
 
IMO, on a car driven on public roads, why? Unless this is a track specific car I'm not sure solid engine mounts have any advantage other than produce a lot of unnecessary vibration with significantly increased driver and passenger fatigue from all that added vibration, noise and more.

Keep in mind road cars are subject to significantly higher suspension bump loads than a track specific car driven on a smooth track unless the car goes "Farming". This will essentially pound the power train (engine-transaxle and all related) with each passing bump. This pounding will aggravate each and every stress riser baked in to the mounting points and all it's associated parts greatly promoting the possibility of stress cracks.

Urethane or similar properly designed power train mounts are likely going to prove to be the wiser choice with passing miles and time.


Bernice


What is your experience with solid mounts and stress cracking? The mounts are very robust; I worry about the rest of the car.

Paul
 
I have fairly long inlets with DCOE webers and plenum in the trunk, I used the original engine mounts but soft mounted the plenum on foam blocks and closed cell foam around the trumpets, works quite well. I do like the NACA ducts, I was thinking of using them but ended up using a scoop instead to try to get more ram effect, on one side only. Don't know if it's any more effective. Engine is 1500, 135 hp @ 7,000rpm.
 

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I have fairly long inlets with DCOE webers and plenum in the trunk, I used the original engine mounts but soft mounted the plenum on foam blocks and closed cell foam around the trumpets, works quite well. I do like the NACA ducts, I was thinking of using them but ended up using a scoop instead to try to get more ram effect, on one side only. Don't know if it's any more effective. Engine is 1500, 135 hp @ 7,000rpm.

This is an interesting approach. Do you have pictures of the soft foam blocks and closed cell foam around the trumpets? How far do the trumpets move during acceleration?

Very tidy work on your installation.

Paul
 
Sorry to get off topic Paul...
Greg I'd like to hear more about your aluminum engine cover. I will be starting a new thread on options for custom engine covers, custom tail-panel treatments, and additional engine air scoops (including snorkels). The NACA duct topic and your rear intake-scoop can also go along there. But I have not started that thread yet, so feel free to post separately or PM me and I'll include it when I get the new discussion going (soon I hope).
Thanks, and back to your regularly scheduled programming.
 
Paul, I would guess the trumpets move + or - 5mm. The whole plenum is very light, so hasn't caused any problems yet, the air filter is in the pod, attached with flexible duct. There are collars around the ram tubes to stop the foam sliding towards the carbies. The foam on the engine side looks black and smooth because it has a thin coating of silicone on it. There are 2 foam blocks under the plenum are nothing fancy, just bonded to the trunk floor and with 1mm thick aluminium on top with a captive nuts and 2 screws through the bottom of the plenum.
Jeff, I custom made the 1 mm thick alloy engine cover as a close replica of a series 1, for light weight as this is basically a track car. Also alloy door skins, trunk floor and front spoiler, fibreglass hood, trunk lid and light weight (3kg) roof.
 

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