Friction Free

[maddogf3]

Originally Posted by blue nose

Royal Purple.

" THANK YOU VERY MUCH " Cheers thats the one ,I new it was a stupid name"

[Al Weyman]

Just an afterthought, as roller rockers may liberate another 40 g-geees has anyone got any for a rover v8 laying about, just a thought

No no Ian the rockers will not liberate that power if any unless like a Chevy you are replacing the original Vauxhall Viva type high friction ball rockers. The gains are when you use ROLLER FOLLOWERS as that is where the real friction in the valve train is, the cam literally directly rubbing on the surface of a flat tappet. Did you know that a chevy engine running roller rockers and followers run at a noticible cooler oil temprature (thus also engine temprature) than one running the flat tappet and roller ball rockers. The downside is you also have to have a special steel billet roller cam and special distrubutor gears (chevy) to get the most out of it and the whole set up with the rockers aint cheap (£1000 plus). I did just buy a mint roller cam off ebay though and paid under 50 quid and it had only been dyno run, I already have the followers and rockers however.

Incidently re your original request, I lent Gerry Cain a roller rocker for his Rover engine and I understand you can use chevy ones in the rover engine. Have a look on ebay for a cheap set, I may have a spare set once I have built this spare engine.

[Al Weyman]

Of course there is always the 6 ft of wire and a cheap toggle switch connected so you can turn the alternator field coil off and on and release another 7 or 8bhp for a cost of what £3 or £4, but lets not have that alternator on/off debate again.

[Chris Y]

Al Weyman - sponsored by eBay

[ian.stewart]

Al
Have you ever seen a Roller Cam for a Rover??, what ratio are your rockers, 1.7?? I really need 1.6,
Ian

[Chucky]

Originally Posted by ian.stewart

Just an afterthought, as roller rockers may liberate another 40 g-geees has anyone got any for a rover v8 laying about, just a thought.

I dunno about 40 but probably 15-20 in a Rover. Try Yella Terra in Melbourne, Australia.

[phoenix]

Originally Posted by graham bahr

yes, however before we get too carried away we should remember rpm, all these savings were talking about only really start to add up at very high revs, pheonix might of found 13brake @ 8,200 but i bet at 6,000 the gain is only half that, and probably only a quarter at 4,000rpm, i think your find frictional losses are like aerodynamic drag, they go up at the square of speed.

Naturally the bhp gain was not constant, though the increase in torque was. @ 6000 rpm the gain was just under 10 bhp. @ 4000rpm it was only 6.5 bhp. As bhp is so important to top speed performance (i.e. max revs in top gear) the gain was clearly measurable on the stopwatch - what else matters? Oh, gaining a place, of course: edging past someone on the straight who edged past you at the last race - that's nice! And the 'How did you do that?' in the paddock afterwards!

[Cleggie]

Originally Posted by dtype38

I'm slightly confused as to whether you want to hold a general discussion on this subject or if you want specific advice for a particular series. Your original post seemed to be directed at a specific series and a specific person Ian_W. If you want his advice why don't you just ask him directly? If you are wanting to introduce this subject hoping he will read it... why?

A number of contributors have tried to make general comments, but you appear to resent these, and you seem to know more about it than anyone else currently on the forum anyway.

I completely agree that, of anywhere on the site, this is the forum that should address this sort of question. It would be nice to think that there are experts who would feel they could contribute their knowledge and experience for the benefit of the rest of us. Unfortunately, I think that taking a combatorial style to getting that information is not only going to fail, but is going to put genuine experts off from contributing.

That's a bit harsh Dtype! I've read MaddogF3's comments that begun this thread, they appeared to be accurate comments as to the efforts current F3 teams were taking to reduce friction, without any 'black art' mythology that sometimes surfaces. That these were easy and cheap fixes that work, were, I believe, merely helpful tips that club racers could follow.

Of course, racers with older cars have to firstly struggle with just keeping thier cars reliable (as I know myself), before they can address the more effective issues Maddog was talking about. Later in this thread it seems that, rather than telling Maddog that his tips were too fancy and the old ways still work, people are now discussing exactly what he first said.

As for the 'genuine experts' that you hoped may contribute, well, I think they already have, or perhaps you didn't notice!

[retro_msport]

Ian ... your cars all over Classic Ford this week .. feature and on Daves rollers

[graham bahr]

Originally Posted by phoenix

Naturally the bhp gain was not constant, though the increase in torque was. @ 6000 rpm the gain was just under 10 bhp. @ 4000rpm it was only 6.5 bhp. As bhp is so important to top speed performance (i.e. max revs in top gear) the gain was clearly measurable on the stopwatch - what else matters? Oh, gaining a place, of course: edging past someone on the straight who edged past you at the last race - that's nice! And the 'How did you do that?' in the paddock afterwards!

phoenix, i wasn't knocking your achivement, but refering to your gain at the sort of rpm which d type's jag engine can only dream about

[graham bahr]

rings are well worth a look at they are a major producer of friction in an engine,i knew one engine builder who built lots of grass tracker mini engines, the rules for that particular championship stated that the engine had to use the origonal 3 compression ring pistons (great for low rpm slogging but pointless at high revs) and have all the rings fitted although any normal production oversize piston could be used, so what did he do?

he used +0.060 pistons but the bottom compression ring was STD size, so it barely touched the bore! it worked and was legal as it had the correct no of rings fitted.

[phoenix]

Originally Posted by graham bahr

he used +0.060 pistons but the bottom compression ring was STD size, so it barely touched the bore! it worked and was legal as it had the correct no of rings fitted.

Don't try that on a turbo engine, Graham!

[Al Weyman]

Chuck is right I have seen Rover rockers from that company and they looked very stout pieces, may be a little over the top in fact but looked bullet proof. I may have a set of 1.6's secondhand when and if I can get the spare off Gerry I will ask him.

Yes Chris I have found some good stuff off ebay for my car. So far the roller cam, a complete MSD ingnition and coil, the best pair of F5000 heads you are ever likely to see, a complete Camaro I am breaking (any one want a completely and I mean completely from water pump to clutch rebuilt and unrun 305 V8 and 4 speed manual see me, excellent for a kit car project!), a Chevy V8 bolt set, Piston rings, my Chevy Blazer tow car, my Brian James Tri-Axle Trailer etc etc etc, I love it!

[johnny yuma]

1.Anyone find electric water pump running off the battery only[ie not alternator] gives a power advantage?

2.Main bearings I guess are like a little brake on the crank. As with a disc brake the larger the diameter the better the mechanical advantage.A six clinder in line is always better off with 7 bearing crank due to 6300 rpm wobble period,but I was amazed once[ please pardon me talking street cars here] driving in the "outback" with no oil pressure,rattling hydraulic tappets etc,after 200km reached a garage,added oil,no further problems for years.Thus I can believe minimal lube on short sprint light weight expensive component cars is a goer.

3. What are the losses through universal joints etc especially if for example the tailshaft is statically off parallel with the crankshaft?

[graham bahr]

johnny in answer to your questions,

1. about 4 bhp on a 1600-2000 4 cyl @7,000 rpm.

2. smaller dia and narrower bearing will absorb less power, so will increaseing the bearing clearances a little, oil pressure, you want the minium needed to keep the crank and bearings apart, for years a ran an engin ewith a mere 40psi oil pressure in competition to no detrement

3. dunno the answer to that one, probably not much as they dont move through much of an angle anyway, U/J's as opposed to Cv's should not run perfectly straight or it shortens there lifespan

[Tim Falce]

Originally Posted by graham bahr

for years a ran an engin ewith a mere 40psi oil pressure in competition to no detrement

I'd love to see 40psi oil pressure on my engine once it is hot.

[johnny yuma]

At the risk of sounding like one of the four Yorkshiremen,ah ewse ta drearm of havin forrty poonds of oil pressure!!