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2006 Lotus Exige
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Discussion Starter #1 (Edited)
I planed on taking my car to the track so I have been taking time to check everything out and make sure it is ready. I have had it a week and half. In that time I have kept it down to about 5K RPM on the shifts. I have only taken it to the shift light once and then after it had warmed up. I didn't want to push it till I had finished going over it. After reading about cam wipe I decided I would check to make sure all was good with my cams. Today I pulled off the valve cover and sure enough The intake cam is bad on two of the second cam (or what ever the high lobs are called) I am not amused.

I try to use only venders with a good reputation that help the community. Since I am new to the Lotus community I don't know who to use.
Could you guys help with the venders that have a good reputation?
Also I am open to any help. I will be doing the work myself so any suggestions on what all I should do will be helpful.
Right now I plan on replacing the intake cam and the rockers.

My Exige has been modded by one of the previous owners. below is a list from the thread when it was done.



Car has new motor with upgraded head (I think its a new short block and reworked head)
tvs900 SC
quaife lsd
Alitexh shifter





Thanks and sorry for the long post.
 

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I highly suggest you spend the night and then some on reading about cam wiping. Causes, fixes and prevention. As far as replacing it all recommend stock grind and better materials is always the way to go. PO of my car had it cyro and tempered treated but BOE and MWR sells a stock grind from harder stock. That would be your fastest option. Get it on order and then do a lot of reading while waiting for the part.
 
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2006 Lotus Exige
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Discussion Starter #4
Friday I ordered A new MWR cam and 4 of their upgraded rockers. I hope this will keep it from wiping agin.
I have spent a lot of time this weekend reading about Cam wipe so I don't really want to turn this into yet another thread but I have three questions maybe someone can help with.

I read some people put on a new sandwich plate with a 200f thermostat. Should I do this also?
I cant remember the brand I read so much its all running together. I live in the south east so I am not sure if I should bypass the coolers. I will be doing a track day in 3 weeks. I will only be doing one or 2 track events a year and some autocross. The rest will be street.

I know different brands of oil will not make a difference but has anyone here used a different weight other that 5w 40? I am thinking about going down to 5w 30.

I never saw anyone talk about the change interval on the oil. I know on Minis if you run them to the OEM milage you are asking for trouble. I change my oil way sooner every 3k. I know this is extreme but it is cheep insurance. Does anyone have any thots on this?
 

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I loved my oil cooler blockoffs I made - I just taped off the inside of the oil cooler intakes (the foam wouldn't touch paint when it was curing), filled it with expanding foam, and cleaned up the shape. I left them in except for on track or in the mountains, and they kept my oil much happier. I use a temp gauge, too, so that reminded me within just the warmup lap that I forgot to remove them. That experience alone tells me you do NOT want to simply bypass them if you do track days unless you plan on bypassing them with a Laminova type setup.

And you really don't want to go thinner with the oil, if anything you want to go thicker since the high temperatures thin it out already. I believe Lotus has an official recommendation on oil weight for hot climates, but I think you should be fine with 40 weight.
 

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Changing out your oil sandwich plate will help you achieve higher operating temps quicker. It would be the fastest implementable solution among those available for solving the problem. However, if you are in the SE and doing a track day in 3 wk, I would tell you this is likely uneccessary provided you do the first lap or two of a session off the big cam. Bypassing the coolers is probably a bad idea in 90F weather unless you also have massively upgraded cooling

Generally speaking, when people change the weight of the oil for track use, the hot weight gets bigger, not smaller. I've got no other advice here.

If you are autocrossing, tracking, running to the OEM mileage for oil changes is asking for trouble as far as I have heard (but i've no numbers to back it up)

I think i a better idea would be to install oil temp/pressure gauges. Then it would be very clear what your oil temps were at any time.
 

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There are many threads on those questions just google around to find but 3K 12mo is average for many and you can block off coolers as a temp fix but still wait ten minutes min after coming to operating temp before hitting second cam
 
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There are many threads on those questions just google around to find but 3K 12mo is average for many and you can block off coolers as a temp fix but still wait ten minutes min after coming to operating temp before hitting second cam
Blocking the oil coolers largely negates the delay in oil temps. I got around 200F in the oil just in one warm-up lap after only idling before that. It also increases the water warmup time since you are rejecting much less heat through the oil.
 

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For tracking, I start the cars in the morning and let them idle while at the driver's meeting. This lets the motor and the trans get heat soaked. The group that I run with has a 30 minute session in the morning that is run under Yellow flag conditions. This is great to finish the warmup of the motor and the trans. If this option is not available, just make sure you take the first couple of laps easy to get all of the moving parts lubed and up to temp.

Later,
Eldon
 

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2005 Elise LSS Saffron Yellow
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If you are autocrossing, tracking, running to the OEM mileage for oil changes is asking for trouble as far as I have heard (but i've no numbers to back it up)

I think i a better idea would be to install oil temp/pressure gauges. Then it would be very clear what your oil temps were at any time.
The stock tune goes pretty rich at sustained high throttle, especially on supercharged engines. That results in a lot of oil dilution in track use, which, as you might expect, doesn't do anything good for the lubricative properties of the oil.

And QFT on the gauges - I have both and now I know when the oil is really warm enough. I have the MWR gauge mount that goes under the dash - it looks good, is unobtrusive, and is, in fact, quite light.
 

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2006 Lotus Exige
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Discussion Starter #11
Thanks everyone for the replying.
I will order an oil temp gage. Where is the best place to tap in for the reading?

The car has a TVS 900 SC from BOE and an ECU tune. At least that is what I believe by digging around on this forum. It was done back in 2015. Two owners ago.

I like the idea of blocking the coolers like @cyow5, But would also like it if would keep the temp good automatically.

Agin thinks for the help.
 

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I am in a middle of maintenance blitz and took my cam cover off yesterday. 17k since my build and knock on wood everything looked as I had hoped. I was dreading what I might see and almost foolishly just skipped it saying whatever will be will be... I was a little concerned because I rolled the dice with original rockers, although my failure mode was not common.

My temp gauge sensor is in aftermarket oil sandwich plate
I have maintenance OCD so my change interval is only 2k, but my DD is a burner so it goes in there...


Glad you caught your situation before it became a real issue. I was ready for what you saw... I have said it before " never send to know for whom the bell tolls, it tolls for thee"

Having swapped out the head myself, I know exactly what bad news looks like...
 

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Discussion Starter #13
@Motard I was like you when I heard about this odd problem I almost didn't check my cams. But after a week I had to look. The day I took the valve cover off I almost talked my self out of it. The car runs like a scalded dog so what could be wrong? LOL.
I am glad I looked, I just want it to stay fixed when I am done. My CFO (wife) is not overly happy I am already spending money on it so soon.
 

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2005 Elise LSS Saffron Yellow
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Thanks everyone for the replying.
I will order an oil temp gage. Where is the best place to tap in for the reading?
If you're using a sandwich plate, get one with a sender port - I believe the preferred one Motard is referring to is the Mishimoto. That will get you the temperature of the oil actually flowing into the engine, which is the most useful number. I'm running something like the EU/UK factory cooler solution, so I don't have a sandwich plate. I haven't identified a place I can tap into the flowing oil galleries without messing something up that would give a supplied temperature measurement. I do have a gPan, though, and it has a sender port, so I've got the temp sender in there. It measures the oil temperature about 1/2" above the bottom of the pan off to one side of the pickup in (I believe) an area behind one of the gates.

What this means is that the temperature reading I get is almost certainly lower than the actual supplied temperature to the engine because a) cooler oil is more viscous and thus tends to puddle in the pan away from the pickup, and b) there are three NACA scoops in the access panel that do a fine job of cooling the bottom of the pan. I know this is true because I can do an idling oil temperature test and then go out for a drive and see the indicated oil temperature decrease (remember, I'm not using the front mount coolers anymore).

With a supercharger you're going to need some kind of cooler. Long term, I'd consider going to a Laminova in your case. Short term, a better sandwich plate with a sender port, oil temp and press gauges, and using a plug on the oil cooler to encourage fast warmups when needed are all going to help.
 

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b) there are three NACA scoops in the access panel that do a fine job of cooling the bottom of the pan. I know this is true because I can do an idling oil temperature test and then go out for a drive and see the indicated oil temperature decrease (remember, I'm not using the front mount coolers anymore).
Your test did not distinguish between the cooling of the NACA ducts and the cooling from the side intakes though, right? (honest question). Unless you have the side ones blocked, I am convinced from my testing (I blocked the NACA ducts and saw 0 change) that the NACA ducts are not only useless but also a detriment to the diffuser. Blowing air onto a flat plate is rarely effective, so you'd need fins on the pan to really make a meaningful contribution from the NACA ducts. And that's assuming they actually get the air directly to the pan, and I am doubtful that's true either.

EDIT: Don't forget the increased outflow, too, from the trunk lid that happens at speed
 

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Discussion Starter #16
I have ordered a temp gage. I guess I will order a sandwich plate next.
 

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We have to compare apples to apples. I have the Boe oil pan, Rev 300 and rear mounted 19 row oil cooler with 200/185 degree therm fan and Mishmoto sandwich plate with 200 degree thermostat, oil temp is bottom of oil pan. With that setup, I had a hard time to get above 150 degrees at highway speed, back roads maybe 160-170. I tried all kinds of different changes, went to a 10 row oil cooler, no difference at all, bypassed the oil cooler, no difference. Finally I decided to block off the NACA ducts just for a test, and that immediately made a difference, so those ducts do work very well. My next move was to insulate the oil lines to the cooler, and then I wrapped the bottom part of the oil pan in 3/8” insulating matting, this gave me the desired oil temps and fast warm up. I see 180 degree after 15 min. of driving and for highway speed it goes up to 190, in traffic and back roads it’s about 200.
Going to the track this next Monday, looking forward to see what my oil temps will be.

1265479
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@CRG53 It'll be interesting to see what your track temps will be. I'm curious to see how much the insulation on the pan effects the temps when the motor is working hard.
Later,
Eldon
 

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@CRG53 It'll be interesting to see what your track temps will be. I'm curious to see how much the insulation on the pan effects the temps when the motor is working hard.
Later,
Eldon
Me too, the forecast is for a 70 degree day, so not too bad, I will post here when I know more.
 
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We have to compare apples to apples. I have the Boe oil pan, Rev 300 and rear mounted 19 row oil cooler with 200/185 degree therm fan and Mishmoto sandwich plate with 200 degree thermostat, oil temp is bottom of oil pan. With that setup, I had a hard time to get above 150 degrees at highway speed, back roads maybe 160-170. I tried all kinds of different changes, went to a 10 row oil cooler, no difference at all, bypassed the oil cooler, no difference. Finally I decided to block off the NACA ducts just for a test, and that immediately made a difference, so those ducts do work very well. My next move was to insulate the oil lines to the cooler, and then I wrapped the bottom part of the oil pan in 3/8” insulating matting, this gave me the desired oil temps and fast warm up. I see 180 degree after 15 min. of driving and for highway speed it goes up to 190, in traffic and back roads it’s about 200.
Going to the track this next Monday, looking forward to see what my oil temps will be.
Those are some strange results (and some expected ones). Since your sandwich plate is 200F, any changes outside the engine won't matter until the t-stat opens, so that makes sense why changing to the 10 row did nothing - it was "off" anyways. And on the highway cruising, you just won't be needing much heat rejection, so whatever you do will be a bit cool, but not THAT cool. I am starting to wonder if the thermocouple is different from what the gauge is calibrated for. Have you confirmed that it is correct? An IR temp gun on the pan will be fine to check as long as you set the emissivity for that of polished aluminum.

I also have a temp gauge in my pan, dual stock oil coolers, and NA. Even without my oil coolers blocked I saw higher temps than you, and that's weird.

Also, are you running a stock rear grill around the license plate or naked? Mine is naked, so maybe I am getting more airflow through the side and don't need the NACA ducts as bad.
 
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