Peter MarieEa

Thanks for the feed back. My 94 HPC is on carbs' consiquently their is no problem getting the engine to spin at the maximum speed the standard starter will allow without the engine firing if the throttles are closed. It is opening the throttles once the engine is spinning that still results in frequent kickbacks. Unless I'm missing something I don't think an interupt button is going to help much. A mate of mine with a Toyota racing engined Seven clone runs 36 degrees of fixed advance had a worse problem than myself; fitted a NipponDenso geared starter and has never had it kicked back since. Hence my interest in a geared starter. Regards, Peter M. Quick7

Has anyone replaced the standard Bosch starter with a Geared Starter? Bosch ofcourse makes them as does NipponDenso. Don't know the fitment model, if there is one for the VX engine. The reason I'm interested is that while my car runs great, I have too much static advance with the standard ignition on my HPC. As a result the engine frequently kicks back when starting. A geared starter would be an easy way to solve the problem. Cheers .Peter M. Quick7

For improved driveability below 3000 rpm the smaller 38mm chokes are the way to go. '94 HPC Quick7

A year or so on this same subject a US contributor highly recommended Honda MTF (manual transmission fluid) claiming it out performed Red Line MTL. I had a 3rd gear syncro' problem in my type 9 gearbox so I gave a try; besides it is a fraction of the cost of MTL. BINGO, syncro' problem disappeared. I should mention that in pumping out the old gearbox oil the last 200mls was gray in colour. It was likely the original oil (12000 miles). So I don't know for sure if it is just fresh oil that solved the problem. Regardless, it's one the easiest problems I've solved on my car. Peter M. '94 VX HPC Quick7

Davesport You've got a good memory about not mixing bean and mineral oil. All currently available synthetic oils are mixable with mineral oil. Peter M. Quick7

Paul W. Interesting stuff you uncover Paul. The TME ester viscosity of 5cSt. At what temp'? What ingredient is AN? It is a wonder how the small boutique blenders can keep up with the likes of Exxon/Mobil. Peter Quick7

Norman, Sorry for the multiple posts; my internet connection is dodgy. One final comment, regarding your use of Mobil 1 15W50. Obviously your start-up regimen minimizes the effect of the 15W oil which is fairly viscous; even @ 40C the kinematic viscosity is 125 cSt. Mobil 1 0W40 is 80C, Silkolene 5W40 is 92 and 10W50 is 116.5. If you engine was modern I'd suggest trying Mobil 1 0W40 or a 5W40 like Silkolene but I suspect you bearing clearances are not that tight (I could be wrong). If you want to stick with Mobil there is nothing wrong with blending grades; you could try a 50/50 mix of 15W50 and 0W40 which would give you a heavy 10W40 and see if you oil pressure when hot is not too adversely affected. Or if you ever go to Europe pick up some 5W50 Mobil 1. It's cSt @ 40C is much better at 105. It is not as shear stable as their 15W50 but then you're not going for long oil changes anyway. Regards, Peter Quick7

Norman, You are to be commended on your warm-up discipline, with one proviso; 50degC oil temp' is not an engine that is fully up to temp' which is 85C min'. I know this time of year in particular it can be difficult to get the oil temp' up, but if you want to minimize engine wear something closer to 85C before extracting max' power would be preferable. Quick7

Norman, Carb' engines, particularily in performance oriented cars which are set up on the rich side to maximize power, do contaminate the oil faster fuel injection setups. Nevertheless you can easily put on 6 or 7 thousand miles per year with a high quality PAO and/or Ester synthetic before the additive pac' is depleted. Norman, you didn't mention how many miles per year you drive your Caterham, but for most of us the mileage is academic due to infrequent useand it is simply a matter of changing the oil annually in the spring. Quick7

nverona, "a BMW 3 running as a new York Taxi" . That a good one i can relate to as one of my tintops is a BMW 328. Must be specializing in transporting midgets; can't see it really. Anyway, Taxi use is low stress on an engine for a number of reasons including very few cold starts. Your more typical taxi in North America is a Ford Crown Victoria with a 4.6 liter 215HP V-8 that routinely rack up 1,000,000 miles with no engine attention whatsoever, and that is on the cheapest bulk oil they can find. The secret to their long life is frequent oil changes (3,000 miles) in conjunction with the high torque, low rpm characteristics of the engine. Quick7

Simon the oilman, Simon I was somewhat surprised by your recommended oil change periods to Petrolhead: Street 6000 miles or annual whichever comes first. Race 5 Hours. Street is fine if somewhat conservative mileage wise but the Track or Race use must be a misprint!!! 5 hours for a high detergent thermally stable PAO/Ester oil? Really it shouldn't make any difference than the street useage. If it was a nondetergent race oil maybe. Red Line for example recommend the same oil for an entire racing season no matter how many race miles you do up to 18,000 miles in total per annum. High temps' and a high stress enviroment doesn't concern them. their oil is that stable. What does concern them is frequent short trips which allow contaminents to build-up in the oil depleting the additive package. High temps, are good for the oil as it boils off condensation and fuel contaminents. Regards, Peter Quick7

Parf7, If you need a OW motor oil Mobil 1 OW40 is better. It's the factory fill on every Porsche that leaves the factory which says something. But it is a light 40wt oil with a Kinematic Viscosity @ 100C of 14.3 cSt and HT/HS viscosity of 3.6. Silkoline 5W40 viscosities are 14.89 and 4.07 respectively, so it is a somewhat heavier oil. I run Mobil 0W40 in my tintops and it performs very well, but my Caterham HPC VX doesn't like it. The hydraulic lifters can get a bit noisy when the engine gets very hot. I don't know what the problem is; perhaps oil airation. The problem doesn't occur with Mobil 1 15W50. and it doesn't occur with the 10W30 Red Line that I'm using at present. Application is every thing when taking about the "best oil". Quick7

Nverona You mean Mobil 1 15W50 don't you? In which case the answer is yes. It is a solid product. The only reservation in this day and age is that it is a bit on the heavy side for starting. I presume you have no lubrication issues? Not knowing how you use your car can't really comment further. Paul Wiley Thanks for the info'. It's not exactly what I'm looking for. I guess the Kinematic Viscosity @0degC is just not available or anything lower than 40degC. Peter Quick7

Petrolhead For both street and track an annual oil change made preferably before the car is chiefly used which for most of us would be in the spring. Quick7

Petrohead I don't think even Simon has claimed that the Silkolene Pro-S oils are the best; very good but not necessarily the best. They are ester fortified PAOs. If I had a highly stressed engine like in the R500, I would give serious consideration to a straight Ester based oil like Red LIne in their 5W40 or 10W40 grades, particularily for the track use scenerio. Not only is the base stock a Polyol Ester but it also contains alot of Moly (MoS2); both of which are polar. The estimated engine life of you engine is only 30,000 to 40,000 miles between rebuilds so I wouldn't compromise. Motul 330V is also worth a look. For street use the least expensive PAO and/or Ester based synthetic you can find would be adequate IMHO. One final comment, it is unfortunate synthetic oil cost so much in the UK. Red Line oil in North America retails for between 4and 5.5 pounds stirling per liter. Mobil 1 between 2.5 and 3.5. Hey, it's almost worth flying over here to pick up a few cases! Peter Quick7