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Discussion Starter #1 (Edited)
Evening all,

I’ve got a 2006 Elise and it’s been running great. On my last service visit, the mechanic mentioned that he wanted to further investigate some “ticking” he heard at idle on the next visit...time didn’t allow him to pursue it while there.

Today a friend helped me pull the valve cover and, sure enough, the number 1 and 3 intake cam lobes have a pretty good ridge in them. NUTS.

Question: I’ve been scouring LotusTalk using Google search and have found many posts about wiped cams but many date back a long ways and so my question is this:

Has there been any solid evidence that any particular aftermarket cams will wear better than a stock Toyota OEM replacement cam? I’ve seen posts by companies like BOE that refer to theirs being harder, etc. but that was a few years back.

A stock Toyota cam and follower kit can be had for about $250. While a Monkey Wrench Racing cam will top $700. Is the added expense truly worth it?

Thoughts?
 

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250 is a pretty hard to beat price. Really depends on your goals.

Just want to get OEM performance back, go with the OEM 250 route. But know you're signing up to do this again several years from now.

Want to avoid ever touching it again and/or performance. Then go with the more expensive aftermarket options with OEM or a stage 2 profile.

Keep in mind the cause of the wiping is still a guessing game. It could happen with any option after enough time and miles.





Sent from my SM-G965U using Tapatalk
 

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Watch out for the OEM cams. We ran into a batch of bad ones. I went that route but the bad part from Toyota caused us to rebuild the top half of the motor. Toyota engineers came out and inspected the engine, admitted that their bad cams caused the problem but the only remedy was to give us a new cam. Which we had to machine before installing. If I had to do it over again, I'd go with the BOE replacement, which is the stock profile. If you stick with the Toyota part, inspect it thoroughly before installing.
 

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Discussion Starter #5
Question...I will have the followers replaced as well as the cam. It looks like Toyota sells the followers only as a set with the cam. I see MWR sells oem followers for $75 each. (Interestingly enough, I see they sell oem cams on EBay for $79 + shipping. I wonder if they are buying the cam/followers from Toyota and then selling the followers at a hefty price and dumping the cams on EBay?)

Is there any other source for followers? I assume going OEM on those with an aftermarket cam is fine?

Sources for followers?
 

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OEM would likely produce the same result. I should know, I went through a replacement OEM in 7k miles. Consider this part from Monkeywrench SKU: MWR-300910-I. It's the same lobe shape but harder material.

Keep in mind that while there are several views on the cause, many point to over-cooing of oil as the culprit and I would agree. Instead of just thinking its the issue, I installed an oil temp and pressure sensors/gauge to validate my numbers. I posted previously about what the oil temp is at various water temps.

As you know, the car let's you hit the high rev cam once water temp is 160 or more,, regardless if what oil temp is at that time. I confirmed oil temp is WAY to low at that water temp to work efficiently at those revs.
 

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OEM would likely produce the same result. I should know, I went through a replacement OEM in 7k miles. Consider this part from Monkeywrench SKU: MWR-300910-I. It's the same lobe shape but harder material.

Keep in mind that while there are several views on the cause, many point to over-cooing of oil as the culprit and I would agree. Instead of just thinking its the issue, I installed an oil temp and pressure sensors/gauge to validate my numbers. I posted previously about what the oil temp is at various water temps.

As you know, the car let's you hit the high rev cam once water temp is 160 or more,, regardless if what oil temp is at that time. I confirmed oil temp is WAY to low at that water temp to work efficiently at those revs.
I wish your chart could be made into a sticky. It's not easy to find.
 

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And don't skimp on the cam installation lube. I have a (completely unsubstantiated) suspicion that Lotus bought engines and let them sit around prior to deployment long enough that some didn't have sufficient lube where it mattered at time of delivery (due to the effects of gravity).

I would have used the harder stock grind cam if it had been available at the time. Although to me, cost of parts pales in comparison to the value of my time investment. YMMV. I put in oil temp and pressure gauges soon after. You can find a bunch of charts (mine included) that give an idea of the lag time for the oil to come up to temp if you look at Exigegus' thread "dual oil cooler, answer to overcooling". My date was at idle but I think others are in motion. My shaky memory says wait at least 15 minutes after water temp up to snuff.
 

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OP, how many oil coolers in your car?

Two is too many.

My notes for new Elise owners say to wait 30 minutes after coolant is up to full temp before engaging "big" cam.

That may not be enough w/2 coolers.

My track days are over (I'm old) so BOE disconnected both of my coolers.

My cams were fine and I adhere to above rule and use Mobil 1 10w-40 diesel.

---

Toyotas with this engine do not suffer cam wiping much, if at all. Their oil temps w/no coolers are not as low as ours.
 

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You mean this?

did a timed "running around town" test and can report the following.
Cold start and go - ambient temp mid 50s F. Time-----------Oil Temp
4 Min 14 Sec = 120 degrees F
(Water temp hit 160, car thinks 2nd cam is OK now but is isn't)
5 min 27 Sec = 140 degrees F
7 Min 33 Sec = 160 degrees F
9 Min 48 Sec = 180 degrees F
This is when I would get on 2nd cam
 

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2005 Elise LSS Saffron Yellow
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You can find a bunch of charts (mine included) that give an idea of the lag time for the oil to come up to temp if you look at Exigegus' thread "dual oil cooler, answer to overcooling". My date was at idle but I think others are in motion. My shaky memory says wait at least 15 minutes after water temp up to snuff.
There's a definite time constant element to oil warm-up time. My hypothesis is that there are two sources of oil heating: bearing surface friction and oil running over water jacket surfaces (as with the oil return from head to sump, splash from the crank on to cylinder walls, etc). If the water jacket is cold, the only source of heating is bearing surface friction, so warm up is quite slow. Once the water jacket is hot, it will heat oil returning to the sump until the oil is hotter than the water jacket, at which point it starts cooling the oil returning to the sump.

An oil temp gauge is somewhat useful, but not definitive, because the senders (particularly on gated pans) generally are located in out-of-the-way places in the sump where the oil is mostly stagnant, so not especially representative of the temperature of the oil actually going to the engine. Short of putting a temp sender in the supply line running from oil cooler to engine, the next best proxy of actual supplied oil temperature is idle oil pressure. Luckily, that's pretty easy to instrument.

Without the instruments, the best you can do is wait the 15 minutes that seem to be a reliable warm-up interval (if your coolant thermostat works well).
 

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Discussion Starter #12
OP, how many oil coolers in your car?

Two is too many.

My notes for new Elise owners say to wait 30 minutes after coolant is up to full temp before engaging "big" cam.

That may not be enough w/2 coolers.

My track days are over (I'm old) so BOE disconnected both of my coolers.

My cams were fine and I adhere to above rule and use Mobil 1 10w-40 diesel.

---

Toyotas with this engine do not suffer cam wiping much, if at all. Their oil temps w/no coolers are not as low as ours.
I have one oil cooler in my car. I recently had the oil cooler line recall done and confirmed there's one. I live in the southeast, south of Atlanta, so lots of warm temperatures. I RARELY get on the second cam (I'm a bit of a Granny when driving) but if I do, it's always well into the drive and have been up to temperature for quite some time.

Car has 29,000 miles or so on it.
 

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You mean this?

did a timed "running around town" test and can report the following.
Cold start and go - ambient temp mid 50s F. Time-----------Oil Temp
4 Min 14 Sec = 120 degrees F
(Water temp hit 160, car thinks 2nd cam is OK now but is isn't)
5 min 27 Sec = 140 degrees F
7 Min 33 Sec = 160 degrees F
9 Min 48 Sec = 180 degrees F
This is when I would get on 2nd cam
Yes, that.......I'll just remember, no second cam until 180F. Not a long wait in summer heat.
 

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TERIB, that's 180 oil. Not water
Yes, I understood that. About 10 mins to get the oil up to operating temperature for safe second cam operation.

I am not sure if you or anyone know why this is. Is the high temperature required for the right viscosity or is there a lubricant that needs this temperature to activate?

If viscosity is the reason, using a 0W-40 oil might help broaden out the safe range for cam lubrication. Of course, knowing the safe zone cannot be determined by temperature measurements.
 

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There is no actual evidence of the link between oil temp and cam wiping, but there is pretty compelling circumstantial evidence.

I would not change oil viscosity

With a Mishimoto oil thermostat[or any similarly designed to actually work] I can rely on my oil being up to temp at about the same time my coolant temp is at its normal temp[which was 184F, but after ECU change is oddly more 188F]
 

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Yes, I understood that. About 10 mins to get the oil up to operating temperature for safe second cam operation.

I am not sure if you or anyone know why this is. Is the high temperature required for the right viscosity or is there a lubricant that needs this temperature to activate?

If viscosity is the reason, using a 0W-40 oil might help broaden out the safe range for cam lubrication. Of course, knowing the safe zone cannot be determined by temperature measurements.
Where did you get 10 minutes??

It's about 30. Engine builders (2) posted this here yrs ago.
 
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