I've been reading Vizard's guide to tuning the A series engine and he says a 998 can rev to around 7k on a semi regular basis fairly happily.

The most I've ever had mine rev to is about 5k. At this point it sounds like its going to self destruct, and it feels like it hits a rev limiter, with power being taken away. Not that my engine is completely standard and so is the carb.

What can I safely rev it to?

What do you rev yours to?

mine revs until I change gears dunno, no tacho

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Lillee - 1969 Morris Mini K

5-5.5K is about it on a stock 998, unless you fit decent (double) valve springs. If you do that, as well as a cam, & head work, 7K is OK.

<edit> my 1310 will go to 8000, but I usually limit it to 7500 on the track- the S crank is at least 35 years old now....

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DrMini- 1970 wasaMatic 1360, Mk1S crank, 86.6HP (ATW) =~125 @ crank, 45 Dellorto (38 chokes), RE282 sprint cam, 1.5 rockers, 11.0:1 C/R.

Cant Wait to put the tacho on Morris and Marcia

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Stop Licking the Dog...I Don't Care Who Started It

0.0 not going yet

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David L


My greatest fear in life is that when I die my wife will sell my Mini and tools for the price I told her I paid for them!

9500

No wait - that's just in my dreams!!

7000 but above 6000, there's no advantage (running 1310 and 40DCOE weber)

kevin.

8000rpm, but now my tacho is gone.... god knows

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Mine currently has a 998 smog head (don't ask) and will only rev to 5,500 and then the valves bounce. My recoed head will have double springs so that won't be a problem any more. I must say, valve bounce is a bit like a hard-cut rev limiter, just makes more noise

I dunno, what would my car be revving to at 150 km/hr on 10 inch wheels??? No tacho

Whatever it was, the poor girl wasnt liking it too much, and I spent the next half hour cooling her down again, before I could shut her down safely

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"He's always been a dickhead, He always is a dickhead, He will always be a dickhead. So stop complaining when he acts like one."

Around 5,770 rpm...

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DrMini- 1970 wasaMatic 1360, Mk1S crank, 86.6HP (ATW) =~125 @ crank, 45 Dellorto (38 chokes), RE282 sprint cam, 1.5 rockers, 11.0:1 C/R.

I have only been to 5500 and that is really harsh on the ears considering the RC-40 is gone and there is a lukey straight through fitted - you need ear muffs in the cabin...usually the gear changes are at about 35-4000rpm - sitting on a easy 100kph at 4100rpm(god bless 3.44:1 final drives!!)

Skins

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Rob Forsyth
Miniot!!

Most std mini engines are unable to get over 5-6000rpms,,,but there`s a bundle of "factory" std engines i`ve seen (been in) that pulled past 6500 on many occasions,,,probably just a fluke of all good things comming together in the right way at the right time at the factory by sheer coincidence...some people call em "Freak" engnes.

that said, a "DECENT" 1275cc (or bigger) "RACE" engine, should be able to pull 8000 + rpms, but in fact, the reality is (sadly) most peoples race engines i`ve seen that other people build ,havn`t quite gone past 7500...don`t ask me why,,,i`d just say that they hadn`t built it right, simple as that.

My race engines have seen over 8500 on many many occasions, only cause i "Allow" them to in the build process.

The truth is that---> EN16T small journal 1275cc cranks are safe at approx 7000

small journal EN40B "S" cranks are safe at approx 8000 (as are our 1415cc stroker cranks)

& std large journal cranks can happilly take 9000rpms all day

The one type of crank that really is the ultimate "bees Knees" for max revs tho, is the Sth African 1071cc "Large Journal" crank,,,this thing is safe(ish) @10,000 rpms all day everyday ,,,i kid you not!!!

I have 2 of these cranks at the moment & hope to buy more in the future, as i`m setting one of them up into a BMW twin cam 16 valve motor bike headed A series engine with turbo charger & electronic engine management system that`s a mouth full ey? I`ve bored the block to make it 1170cc so as to keep it under the 2litre class specs for CAMS racing with their multiplication factor for capacities.

YUMMY tell your mummy

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No offence intended here but--> anyone writing a book about minis 30 years ago may not have experienced such worn or stuffed-with components as we are finding these days.

You should put your heart & soul into everything you do.

what about the sth african 1275's?, that is what mine is,

ive had mine to 7800 on the odd occasion, but i only change gears out of genorosity for the engine (and neighbors) its had no ill affects taking it up this high. , no valve bounce or running out of puff.

cheers steve

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Cheers Steve.


1973 south african mk3, 1275 +30 (1300), RE13 cam, hif44, mildy worked head with s sized valves, pulsar dizzy, 1.5:1 minispares forged rockers.

My Cooper s i don't take past 7k, my 1427 stroker i DON"T take past 6k as the crank is too valuable, plus its already making too much grunt.

Doogie

Steve&Sash,,,Your crank would be a Large journal 1275cc (i`d expect) unless someone changed it over to a small one (which i highly doubt) & therefore would be right to rev to approx 9000rpms(ish) (as long as it`s not allready been badly fatigued,)!!!!!!!!!

This only says things about your crank`s strength tho,,,the rest of the engine is what normally restricts the revs,,,things like valve bounce, crank whip, clearances too tight, camshaft not big enough & cyl head not flowing enough, engine not well balanced, etc etc etc

then there`s all the "Tune" stuff that can also cause a shortage of revs,,,things like, carby mixtures, distributor advance curves, manifold flow characteristics, exhaust system restrictions & lengths, engine temps, etc etc etc

Now i`m not going to start to write up a book on "How to make your engine rev harder" here,,,no way!!!,,,i`d end up with sore fingers & no sleep. But there are heaps of small things that can be done to even a street engine to help make it rev higher,,,as i said earlier, even the factory got it right --->(sometimes)

2 "S"`s & a clubman... i too like the strokers grunt factor (yeah YUMMY tell your mummy!!!) but i also enjoy reving them to,,,my 1510cc donk has run quite regularly to 7600 for the last 8 or so years & was only built up in road form,,,i can only imagine that it would have gone "BANG" had i actually made it into a race engine & tried to rev it hard tho.

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No offence intended here but--> anyone writing a book about minis 30 years ago may not have experienced such worn or stuffed-with components as we are finding these days.

You should put your heart & soul into everything you do.