Pee Wee's Big Adventure

[jbcollier]

I took my S1 out for its first long road trip.  An 1825 km round trip to Nelson BC from my home in Edmonton AB.  The weather was cool with occasional showers on the way out, and hot for the return. The roads and scenery are amazing and I managed to time it to miss most of the traffic.  I was typically humming along at 4K rpm in 5th which works out to roughly 125 kph.  The police were very kind and no official hinderances were encountered.

https://jbcollier.smugmug.com/Lotus-Europa/i-zRmbSrs/A

Made it all the way with very few issues.  My AC and 100w alt run off the same belt and that proved to be a bit taxing:

https://jbcollier.smugmug.com/Lotus-Europa/i-pCH6ZVb/A

I had a spare but it survived all the way home, no problem.  I'm going to try a larger idler pulley first.  I may end up having to convert to dual belts.

Still some lingering vibration at high speed so It’s time to sort that ancient tire shaver I have lying around.  Fortunately there were sweet spots where it completely disappeared — 125 kph for example.

https://jbcollier.smugmug.com/Lotus-Europa/i-vJB4K78/A

Handling is sure and positive at low to medium speeds but a wee bit nervous in high speed corners.  It feels like the front and rear are slightly "disconnected".  Will recheck the alignment all round now that things have had a chance to settle in.

https://jbcollier.smugmug.com/Lotus-Europa/i-Dd7Nj3q/A

The AC worked like a charm — other than the belt.  I do not have it set up to recirculate but there was ample amounts of ice cold air once the revs were up.  Very pleased and a real life saver on the way home.  Temps remained cool on the highway but crept up in stop and go traffic with the AC on, hardly surprising.  I once saw 110C on the gauge but it quickly went back down at speed.  No coolant loss or unsettled running so the gauge may be reading a little high.

It’s noisy in the cab at speed, very noisy.  I used a rally intercom system with a mic-ed headset (like a helicopter).  Worked very well.  I could listen to my music/books and take calls.  Ears got a little sensitive after five hours though.  And I had temporary funny lumps on the top of my head — a serious issue for us bald people ;-)

https://jbcollier.smugmug.com/Lotus-Europa/i-srjp9dM/A

Power is adequate with the car being “60s” fast.  Football/soccer moms in their 300 hp mini-vans have no problem dusting me at the lights. Which leads to the strange phenomenon of struggling to pass in twinned passing sections — where the 80 kph travelling F/S mom/dad speeds up to 150+ — but being able to handily pass in short, single lane sections in the mountains.  People are odd.

In summary, the oft-repeated war cry of the sports car enthusiast, “Delighted and there’s just a few issues to sort…”

[BDA]

Thanks for the trip report, JB! It sounds like it was enjoyable and successful!

I would guess that the A/C is robbing you of some power but the comfort in hot weather has got to be such a huge plus that it must be worth it. As for outdragging minivans, besides the drain from the A/C, the bottom end torque is wanting even for a 1400# car.

Your car must be REALLY loud. Didn't you install a SuperTrap muffler along with a conventional muffler? I would have thought that would be sufficient. My car has stainless headers that empty into 2 1/4" exhaust with a single conventional muffler. It's loud but you can have a conversation - albeit at an elevated volume. I can even listen to my radio! The problem is that when I adjust the volume for higher speed (i.e. noisier conditions), it is too loud when I come to a stop light!

Mine has some handling issues, too. On high speed corners, it feels like it's trying to swap ends. Alignment is the first obvious place to look. Since I had to fool with my steering rack, I'm going to revisit that with more careful attention to the resistance at the pinion shaft and tie rods. I also don't remember if I paid attention to the "handedness" of the trunnions, I probably did, but I'll check that, too. I welcome other suggestins.

Congratulations on your successful trip! May you have many more!

[surfguitar58]

I've told my wife A/C is not an option in the Europa. Let's keep the possibility our little secret.

You have a beautiful photogenic car JB. The lines of the S1 before they monkeyed about with fed mandated headlight heights is truly gorgeous. Congrats on your big day!

Tom

[dakazman]

Congrats on your road trip.
That belt really got chewed up . Your thoughts on an adjustment of the tensioner , I believe I saw on your build. Some of my vehicles cycle with oil pressure. They also add some rpm at idle.
Dakazman

[Certified Lotus]

JB, I have huge admiration for anyone who engineers their own design and solutions for historic cars. Fantastic work!

[Rosco5000]

Hey John,
Looking at your belt route, do you need to run a vbelt back to the idler like that.  I know you don't have a lot of contact area on the alternator if you don't but you don't often see v-belts like that run on an idler very often, I only ever have seen poly-v run like that.  Do you think you would have slippage issues with a shorter belt and skipping the idler?
Ross

[jbcollier]

Good question.  I think the answer is that I do need the idler for the increased wrap on the pulleys.  Even with the increased wrap, the belt has to be tight or it will slip.  The best solution would be to fit twin belts.  The small belt from the cam to the water pump also has to be tight but it has good wrap and is "bent" the right way so it lasts just fine.  I'm going to try a larger idler pulley first -- I'll just press one onto the existing idler.  That will reduce the amount the v-belt is "bent" backwards and increase its life.

I'm thinking as I'm typing this... I could add another pulley to just the water pump and then run separate belts to the compressor and alt.  That would give me excellent wrap and no reverse bending of the belts.  I'll explore that option as well.

PS:  I'm no great shakes at all this.  I've seen better, much better, by others and other forum members.  I guess my one good quality is that I'm not daunted but intrigued by failure.  It makes me want to figure out why and sort it properly.  Even more fortunately, I make lots of mistakes and thus have lots of opportunity to practice ;-)

[GavinT]

I guess my one good quality is that I'm not daunted but intrigued by failure.  It makes me want to figure out why and sort it properly.  Even more fortunately, I make lots of mistakes and thus have lots of opportunity to practice ;-)

Ha . . join the club.
Sometimes I come up with a "brilliant solution" for some problem or other and fabricate a widget to fix it.
Upon installation, I find it didn't really work as I expected so it's back to the drawing board.

By the time I get to Version 3.2, it usually solves the problem.
At that point, I wonder how I ever thought Version 1 could possibly work.

[BDA]

Failure is the best teacher. Not being stopped by it and persevering through difficulties to analyze and then solve problems and then carry the knowledge further to the next problem speaks highly of you, JB, but then we are not at all surprised that you have those qualities.

[EuropaTC]

Hi John. Now what I'm about to post is probably poorly thought out rubbish so I'm very open to debate or correction on this.

My initial reaction was like Ross in that I'd not seen a toothed V belt run like that and too much flexing was the problem.

But after looking at your photo. one thing that came to mind was "is that double idler pulley a solid thing with the large & small diameters fixed together ?".  If it isn't, and the two rotate independently then ignore the rest of this waffle ! 

What occured to me was that where I've got an idler tension it has always been on it's own, a free-wheeling pulley that is entirely driven by the belt it's tensioning.  If it's driven independently from the tensioning belt with a secondary pulley then you get into heavy (for me) maths to ensure the belt speeds around the two diameters are the same. If they're not you might end up with some tension or even slippage at some point depending on which belt makes the running.

So....  if the double pulley tensioner is a rigid assembly, is it worthwhile fitting a secondary tensioner just for the alternator or could you dispense with the tensioner aspect on what I assume is the water pump ?

Brian

ps - also apologies if the above is a) complete rubbish, or b) you've done the calcs and I'm still talking rubbish !

[jbcollier]

The v-belt idler is a timing belt idler secured with a long bolt and a nord-lock washer to the camshaft.  The v-belt idler has internal bearings and rotates concentric with, but separately from, the stock camshaft pulley.  It's an unusual set-up but no laws of man nor nature are being violated.

[surfguitar58]

That is a beautiful setup John. Looking at your work is like engineering porn. But, just adding to the Monday morning quarterback, second guessing rubbish heap, my gut reaction is that your idler is a bit small in diameter. Add to that that it is a backwards bend, and I wonder if the reverse bend is fatiguing your belt. No doubt that is why you selected t toothed belt over a solid vee, and the idler obviously has no load on it, but still the belt seems to be flexing on a 1.5 inch back radius on the idler to a 1.5" forward radius on the alternator in rapid succession. Might doubling the diameter of your idler save your belt? Again beautifully executed and consider my observation just more crappy commentary from the peanut gallery. http://www.durabelt.com/crosssectioncalcinfo.php
Tom

[Rosco5000]

I wonder if you rerouted the belt to reduce the number of degrees it wraps around the idler pulley if it would help.  See picture below.  Still helps increase your alternator contact on the pulley but it will put less stress on the inside edge of the v-belt that seems to getting damaged quickly.

[EuropaTC]

The v-belt idler is a timing belt idler secured with a long bolt and a nord-lock washer to the camshaft.  The v-belt idler has internal bearings and rotates concentric with, but separately from, the stock camshaft pulley.  It's an unusual set-up but no laws of man nor nature are being violated.

ahh, I get it. Couldn't make that out when I was first looking but now you've explained it I can see how it works.

Brian

[jbcollier]

Hit the nail right on the head Tom.  The idler is too small in diameter.  I have been reading engineer manuals on belt drive design and they suggest a minimum of 1.5x the smallest pulley.  They suggest that belt life will still be negatively affected but should be closer to norm than with my present tiny idler.

I thought of that as well Mr Rosco5000.  It would significantly reduce wrap on both the compressor and the alternator.  It will already slip if the belt isn't kept very tight so I think routing the belt that way will make things worse.