How high do you rev your Stag?

[Paul Kelley]

As a variation on the 'how fast have you driven your Stag?' thread (started by Essex Stag), this is a debate about the related but different point about how high people tend to rev their TV8s. I started out, nearly two years ago now, being wary of using much over 4,000 rpm and often less than that. Because the engine was burning some oil and had not been used much by PO I decided to make the engine do some anti-glazing work by loading it in 3rd gear uphill. Thank you Motorsport Micky on the forum for that tip. Plus, on advice from a long-standing Stag owner, I started revving it to 5,500 on occasions. All of which, together with VR-1 oil, has lead to a much better performing engine and a reduction in oil.

The red line is set at 6,500 for a reason after all. The TV8 is oversquare with an OHC (no push rods to bend - just chains to wear out!) and produces max power high up the rev range. Whilst it sounds cool burbling at 1,500-2,000 revs through stone-walled villages it seems equally impressive, and happy, being given the beans at the top end too. That said, I tend to limit myself to 5,500 in respect of its age and a sense that that's enough! As for top speed, I think that's less of an issue in the real world. Stags cruise happily at motorway speeds and can therefore keep pace with modern traffic and overtake when needed, which in my view is the main thing.

What are your views on treating the TV8? Rev it or be gentle? And what about the automatics' experience? Do their engine last longer perhaps? Or do they glaze up?

Paul K

[Pete]

To be honest, whether I'm driving my Focus, Transit or Stag, I tend not to push the revs, especially as the Stag and the Focus have so much torque. I keep to speed limits and find that traffic lights mean I keep up with the wheel spinners anyway. Why waste fuel? Whenever I have driven hastily I've saved minutes rather than hours so what's the point?

[Westfaling]

Now run in I occasionally rev mine to 5500-6000 for fun. I usually keep it to 4000-4500 in normal driving.
Nick

[mole42]

Mine's got a ZF four-speed auto, so it really never gets past 4000rpm unless I hold it in third on the motorway, but then, what's the point?
It used about half a pint of oil on a 500 mile run to York and back recently, steady 55ish on the way up in the rain, steady 70ish on the way down in sunshine. I was surprised because in normal day-to-day running around it doesn't use oil at all.

[Stagless Steve]

The previous owner of my Stag who rebuilt the engine said he kept below 4500 RPM so I have stuck to that. I have wondered if it would be safe to go higher but my philosophy is that it goes well enough being limited to 4500 so is it worth the risk of pushing a 43 year old engine, albeit a rebuilt one, just for the hell of it?
Steve

[marshman]

Mine is a BW35 auto so it is difficult to get the revs up in normal use, but because I am a big kid (read old kid) and love the sound the car makes I will quite often hold it in 2nd and keep my foot down. Can't remember what the revs get up to but it is certainly way above 4500. The TV8 revs freely and I have no qualms about reving mine to the red line - after all that is what it was designed to do.

I appreciate the comments about wasting fuel etc but lets be honest if that really was a concern you would not be driving a Stag - or most other old classic car for that matter. Having said that when swmbo is in the car I do get told off and I then go into relaxed mode and just burble along which I must admit is just as pleasurable - it's just the grin factor is not as big

Roger

[wilf]

3500 - 4000 is where the fun starts anyway on mine, isn't peak torque around there?

But I tend to shy from hitting the redline these days, haven't changed the chains yet.

[Kevin Garrod]

I don't normally rev it very high, however I did nudge 7000 going up Prescott Hill one year.
Stagmuffin will be along in minute as he's beaten that by some margin!

[stagmuffin]

few years back now but cant forget that day a power challenge at an enginuity open day arranged by Tony hart what a day that was , if i remember correctly my engine made about 8200 rpm although there was no extra power by then there was a requirement for new undergarments !! and the same engine still breathes and will be powering another beasty soon with fuel injection

[DJT]

Whilst playing around with the throttle cable the other day I note that the throttles were'nt fully open with the pedal on the carpet. Then I remove the bolt that goes through the pedal itself and acts as a throttle stop. This allows full movement of the throttle linkage at the carbs. Yesterday I tried it out as I joined a dual carriageway from a slip road. The ZF held 2nd gear right up to 6000 rpm and I had to back off as it change to 3rd!

[jakesmig]

Not TV8, but I occasionally go to 6500 in the low gears with the 3.9 RV8, and I use up to 8500 with the 1.8 K series in the Midget, both without any apparent difficulties. To ease the burden on the diffs, drive shafts etc I don't do 'burn outs' and don't spin the wheels up on take off, don't see a problem spinning them up once the car is moving but generally a habit I try to avoid.

John

[pitzey]

I just cruise in mine , however the porsche is a different matter

[flying farmer]

I asked Tony Hart about the safe revs for a Stag engine before I started my project Stag engine build.

Assuming it has all been put together properly, Tony reckons the standard pistons are good for 7300, after that they tend to throw the crowns off so I don't think Stagmuffins engine could have handled 8200 for long ( I was there when it happened).

Fortunately the Stag engine is of large enough capacity that it doesn't need the nuts revving off it in normal use, but sometimes when overtaking it is nice to wind it round the tacho and avoid that inconvenient gear change.

A couple of weeks ago up a very long steep hill I was attempting to overtake an Audi Turbo diesel in my old Stag, and he wasn't having any of it. I said to SWMBO "he will run out of revs shortly and have to change up". He did, and it was like he had run into a wall. The extra couple of thousand revs available from a petrol engine can often defeat diesel torque when they have to change gear!

Apparently the crank and rods on the Stag are good for 8000rpm but forged pistons are needed, and the block needs bracing between the main bearing caps and the sump bolts to avoid cracking the block. Necessary for a racing engine that spends a lot of time at high revs, but rather a case of overkill for a road engine as the camshafts required to make use of that RPM may not be particularly user friendly on the road.

Having said that, looking at the fuel map for the megasquirt on the project Stag, it might peak at well over the 7000rpm limit I am using and that is a road driveable cam profile.

Question is, if it does peak at very high revs, how long will I be able to resist the temptation to start all over again with another engine?

Neil

[pollystag]

few years back now but cant forget that day a power challenge at an enginuity open day arranged by Tony hart what a day that was , if i remember correctly my engine made about 8200 rpm although there was no extra power by then there was a requirement for new undergarments !! and the same engine still breathes and will be powering another beasty soon with fuel injection

Ha, i was there that day!

[marshman]

Just been for an mot and on the way back took note of the revs. Foot hard down revs to around 4500 in second before changing up. If I want a real grin on my face hold it in second up to 5500 or so. (Approx 70mph). I do this quite often, sounds fantastic and is really smooth not at all 'thrashy' like some engines get.

car has a standard tv8 with points, strombergs and bw35 box.

Roger