underated 1098?

[BaritoneUke]

Having just read calvers take on tuning the 1098
https://www.calverst.com/technical-info ... potential/
I wonder if this engine could be another direction for people to head in now that 1275 engines have "gone through the roof" as someone recently put it (noticed a well used, rusty looking 1275 with a stiff crank on the web for a little over £900 recently).
He measured peak torque at 59ft/lb with only a few mods, mainly an improved cam and custom dizzy (not sure how available that last part might be). Probably with bigger valves than the standard moggie head but work can be done on them.
Could this be coupled with a 10CC block (if you can find one) to create an extremely reliable, tractable road engine?

[philthehill]

Having read the Calver link it still reads 'Spend Money' which ever way you look at it.
Also it may be cheaper to find and purchase a 1275cc 'A' series than a 10CC 1098cc engine.
10CC engines are getting rare (if not already rare) and so there will be little difference between the overall costs.
You can always fall back on a 1275cc transverse engine though some mods will have to be undertaken to suit the inline configuration. 1275cc transverse engines seem to be still plentiful.

[BaritoneUke]

You can always fall back on a 1275cc transverse engine though some mods will have to be undertaken to suit the inline configuration. 1275cc transverse engines seem to be still plentiful.

Never even crossed my mind this...do you know roughly what mods are involved?
- drillings for a bell housing I suppose...if you want a 5 sp box this could be sierra?

[philthehill]

https://www.youtube.com/watch?v=9sxy1pUq83Y

[BaritoneUke]

https://www.youtube.com/watch?v=9sxy1pUq83Y

Interesting idea but he reckons on 4-5 hours of machining...so unless you do your own machining you're paying money to somebody there too. Gearbox is prob. stronger. I'll see what the bottom end and bores on my donor 1098 are like this week, then I'll have to make a few decisions.

[philthehill]

The reality is that you will have to spend money whatever you do even if you try to do it on the cheap.

[kevin s]

The 1098 is always going to be an issue if you go for max power and consequently high RPM, for a road car most people won't go much over 5000rpm. We have re-built a 1098 with a raised compression (around 8.5:1), re-shaped ports and combustion chamber, a high lift but modest duration cam, damped pulley and mappable ignition, at the moment it is still on the std inlet and exhaust but even like this it has noticibly more torque and romps up hills in top you would have needed 3rd for before. It does start to feel strangled at 3500rpm plus though. We are building up a LCB, sports exhaust and twin carbs for it at the moment I'm hoping this makes a difference in the 3500 to 5000 rpm range.

I expect the crank centre bearing will wear and did think about strapping it but in the end I was worried about the cap getting lost or damaged and concluded even if I have to change it it every 50,000 miles is not a massive job.

we do have a maestro 1275 which one day I plan to fit a MX5 gearbox to but that is very much on the back burner at the moment.

[BaritoneUke]

re-built a 1098 with a raised compression (around 8.5:1), re-shaped ports and combustion chamber, a high lift but modest duration cam, damped pulley and mappable ignition

Very interesting, I'm keeping an eye out for an affordable 10cc (mg) block, and I have an lcb, good inlet manif'd, big valve head + HS4, Calver hi torque cam in the works. How did you do the ignition? Calver specifically mentions this in his article - thanks.
Richard

[kevin s]

I fitted a toothed wheel to the crank pulley and megajolt system, which works a treat.

[BaritoneUke]

I fitted a toothed wheel to the crank pulley and megajolt system, which works a treat.

Thanks, will look into that...new territory for me

[Blaketon]

WO Bentley said there is no replacement for displacement, so perhaps the 1275 is the ideal compromise. I know MGB engines have been fitted but it's not easy and I think the weight distribution is upset.

I've driven 1098 cars and they seemed to go along well enough. The later 1098 Midgets went quite well, giving 60bhp, which I think would propel a Minor reasonably well, especially the lighter two door saloon or convertible.

The 1275 engine is derived from the Cooper S engines, that all had the same 70mm bore, with varying strokes. The reason, for the big bore, was to accommodate larger valves, which won't really be an issue unless you are after lots more power. I'm surprised at the cost of used 1275 engines but I suppose it's a long time since inline 1275s were used in cars (It's a bit like Ford Sierras; there are far more gearboxes left than cars). Having said that, it's still probably cheaper than fitting a supercharger to a 948 or 1098.

If I had the time and didn't already have a 1275 engine (With a spare - shared with one of the Midgets), I think a Triumph SC 1500 engine, with the overdrive gearbox (Of which I have spares for the other Midget) would make a very nice, torquey unit for the Minor. Aside from the work needed to do it, that could lead to complications, concerning classification of vehicle/MOT regulations.

[BaritoneUke]

Blaketon:
Nice to get a different take on it! A lot of posts I've seen suggest that the triumph engine was a bit of a dog. But I know very little about it.
Yes, MGB would be a job! And prob. not worth it. But spridget 1098 (10CC block, big valve head) and there you would be on the money I think. If you want a 1098 that is, and I'm certainly inclined that way. Might even come with a decent cam but I haven't looked into that yet.

But on reflection, I think a 1098 (10CG block) could be made into a much better daily drive with cam, manifold, extractor...if balanced, damped and driven with respect.

[Blaketon]

So long as you remember that the Triumph is long stroke and make sure the crank end float is OK (Quality control could be hit and miss), they are OK (Jigsaw Racing ran them up to 8000 ). They gave more trouble in Midgets, due to poor oil cooling. I've not put a rod out in nearly forty years; good job this desk is wooden.

Might be worth getting a copy of David Vizard's A Series book and having a word with http://www.peter-burgess.com/ .

[BaritoneUke]

Might be worth getting a copy of David Vizard's A Series book and having a word with http://www.peter-burgess.com/ .

My copy of Vizard's book is well thumbed, but I still only partly understand compression ratios

[panky]

I fitted a 12G940 head off a 1275 Mini to my standard 1098 block. There can be exhaust valve to block face clearance issues which can be sorted in a few ways:- recessing the valves, pocketing the block or, as in my case, skimming the valve faces ( I was lucky as the head hadn't been slimmed so very little extra clearance was required). This combined with a HS4 carb and Midget exhaust manifold into an 1 1/2" exhaust system gave a nice lively performance much better than standard. I then fitted a 3.7 Riley diff which dampened the extra performance but gave the car nice longer legs.

[Bill_qaz]

So long as you remember that the Triumph is long stroke and make sure the crank end float is OK (Quality control could be hit and miss), they are OK (Jigsaw Racing ran them up to 8000 ). They gave more trouble in Midgets, due to poor oil cooling. I've not put a rod out in nearly forty years; good job this desk is wooden.

Might be worth getting a copy of David Vizard's A Series book and having a word with http://www.peter-burgess.com/ .

You maybe interested in this https://youtu.be/ow5cGV7bXCw?si=-yfz-a3OLXfzlKbt

[BaritoneUke]

I then fitted a 3.7 Riley diff which dampened the extra performance but gave the car nice longer legs.

Hi Panky, yes I'm heading in very much the same direction. Spridget head (206 in my case), HS4, maniflo inlet, ESM extractor & system, better cam. Just found a 3.9 diff, now just the little matter of assessing/rebuilding the engine and fitting the bits Going to experiment with rear wheel profile, I might be able to lower that final ratio a little bit more...

[BaritoneUke]

So long as you remember that the Triumph is long stroke and make sure the crank end float is OK (Quality control could be hit and miss), they are OK (Jigsaw Racing ran them up to 8000 ). They gave more trouble in Midgets, due to poor oil cooling.

Read up a bit on the triumph engine - quite a torquey lump, quite inexpensive from midget/spitfire breakers and good spares support - and much cooler under a moggy bonnet (but I've got my hands full at the moment )

[Blaketon]

So long as you remember that the Triumph is long stroke and make sure the crank end float is OK (Quality control could be hit and miss), they are OK (Jigsaw Racing ran them up to 8000 ). They gave more trouble in Midgets, due to poor oil cooling.

Read up a bit on the triumph engine - quite a torquey lump, quite inexpensive from midget/spitfire breakers and good spares support - and much cooler under a moggy bonnet (but I've got my hands full at the moment )

I fitted an oil cooler (With thermostat) to my Midget 1500, moved the number plate out of the way of the air intake (Which was also enlarged) and got vents put in the bonnet. It has improved the cooling no end. Fitting an overdrive also makes a difference and if I was twenty years younger and not wanting to finish with "Projects" (Having done my share and now wanting to just maintain and enjoy), I could be very tempted.

[Blaketon]

So long as you remember that the Triumph is long stroke and make sure the crank end float is OK (Quality control could be hit and miss), they are OK (Jigsaw Racing ran them up to 8000 ). They gave more trouble in Midgets, due to poor oil cooling. I've not put a rod out in nearly forty years; good job this desk is wooden.

Might be worth getting a copy of David Vizard's A Series book and having a word with http://www.peter-burgess.com/ .

You maybe interested in this https://youtu.be/ow5cGV7bXCw?si=-yfz-a3OLXfzlKbt

Very much so, thank you. Have already passed to a friend and I've not yet watched it.