LM002 RHD Rolling restoration.. will be updated regularly

Hmmm...

Maybe I should get some carb motor cams

 

What is a microplex?

 

Brian,

300/280 degree cam is borderline RACE cams. Also the 70 deg overlap is huge.
It should give the LM a very rough idle and useless torque below 4000 rpm, not very good for a 7300lb tank.
Are You sure it is 300/280 ?

BMW E34 M5 Shrick upgrade 280/280 is already high, IIRC the standard M5 camshaft is 274/274


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Performance Camshafts: Increase The Power of Your Ride

High performance camshafts start at 280 degrees of duration. These performance auto accessories have increased valve overlap but not too much so emissions and fuel economy are not severely affected. These are generally good camshafts for modified street cars and produce good power from 2,500 RPM up to 7,000 RPM but they do not have a smooth idle because of the increased valve overlap.

A 290 degree camshaft requires more cylinder head work in terms of cylinder head porting and gas flowing as they work better when the engine's Volumetric Efficiency (VE) is improved. As you'd expect, these camshafts produce a fairly rough idle. These camshafts are generally good for rally cars and produce power from 3,000 RPM up to 7,500 RPM.

A 300 degree camshaft requires even higher levels of VE, reaching the physical gas flowing limitations of a two valve cylinder head with a single camshaft. These camshafts are good for modified race cars and produce good power from 4,000 RPM up to 8,000 RPM. However, they have a very rough idle.

A camshaft with a duration of more than 300 degrees is an out and out race camshaft with a power band in the 4,500 RPM to 9,000 RPM rev range. To make effective use of a 300 degree camshaft, you need to ensure that the engine has a very high VE. You also need to ensure that the engine can rev beyond the red line of most stock engines.

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http://www.crower.com/media/pdf/regrinds.pdf

Look at right table #6 road racing cams

 

They measured differently for sure
eg : 295 liters is 195 liters

 

Thanks for the data Victor.

 

There must be something wrong with our local dyno here, some adjustment is needed.
It is impossible mine is losing 100 whp on a healthy engine.

This coming saturday I will do a road acceleration test with my Gtech Pro
G-TECH/Pro Homepage

 

Victor,

I did my dyno pull using 3rd gear not 4th, the dyno operator was reluctant to use 4th gear. Is there any difference in the result ?

 

Interesting air filter configutration.
Lambo did throw away the Donaldson tractor air filter for Paris-Dakar
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68 liter per 100 km ?
1.5 km per liter (about 3.6 mpg ?)

I thought mine was bad, in fact it is the normal fuel consumption.

So the Rally LM has a 600 liter fuel tank.
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Hmmm...
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Nice drive from 7am to another town, although being Saturday the road still has a bit of traffic near the toll gate.

Total distance driven today is about 130 km round trip.

Water temp is fine in the morning. 79C on long straight and 85C on bad traffic.
Later that day when ambient temp rose (quite a hot and humid day today, it rained later in the late afternoon) the temp rose up to 98C on a stuck traffic and 89C on a slow road.

After today's drive I am convinced that the Donaldson air filter is choking the engine. Next plan is to modify the air intake system.
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On the way back to Jakarta 9am was good, the road is clear. Indra drove it to 160kmh indicated speed or about 140kmh.
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Dropping by a friend's house otw home.
Nice to see all 3 cars have basically the same engine.
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