Simple 1098 Engine Mod

[Morrisito]

Hello there,

I've just bought a beautiful 2door which I'm going to keep forever and I want to get a bit more power out of the engine...

What simple modifications can I do to my 1098 A series engine?

Is it easy to find things like stage 2 heads, a fast road cam etc

Any advice would be greatly appreciated!

[Kevin]

Hello there,

I've just bought a beautiful 2door which I'm going to keep forever and I want to get a bit more power out of the engine...

What simple modifications can I do to my 1098 A series engine?

Is it easy to find things like stage 2 heads, a fast road cam etc

Any advice would be greatly appreciated!

The answer is yes.
The biggest factor to start with is how much increase are you trying to achieve and what sort of budget do you have as it can cost more to uprate a 1098 engine that fitting a 1275 it just depends on what you want, can you be a little more specific also can you do the work yourself or do you rely on others.

[Morrisito]

Thanks for info..

I want to increase to 70bhp...

[Morrisito]

i rely on the help of a good friend that I live with...hes got a mk3 2door cortina and he loves to tinker

[bmcecosse]

For close to 70 bhp (probably more like 65) - you should fit a 12G940 cylinder head from a 1275 engine. Along with a larger carb from a later Mini (HIF 38 ) on an MG Metro inlet manifold - and a good exhaust manifold and a larger bore exhaust system. However - your target HP is hardly in the range for a 'simple modification' to the 1098 engine. The engine itself would need to be in tip top condition - absolutely no point doing this work on an engine that has dubious oil pressure and/or smokes and burns oil! A 1275 swap will give a more 'relaxed' 70 bhp if fitted with an HIF 44 carb and same manifolding/exhaust as above. Cam change is not really necessary - however the MG Metro camshaft would give a useful extra 5 bhp to either engine spec.
Make sure the brakes and suspension are up to top condition before worrying about more power!

[ssnjimb]

Hello.

Just reading this post.

would cleaning up the ports give 1 or 2 bhp.

The hif carb what work is required to fit one of those and what difference is there to a su hs2

James

[bmcecosse]

1 or 2 bhp was not what was asked for! And would not be noticeable anyway. It takes more than 'cleaning up ports' to make worthwhile extra power. Carb is larger diameter and better design with integral float which eliminates surging on corners!
Buy a Vizard A series book - always plenty on ebay - and read all about it!

[Kevin]

Hello.

Just reading this post.

would cleaning up the ports give 1 or 2 bhp.

The hif carb what work is required to fit one of those and what difference is there to a su hs2

James

If you are just after a small increase using the next size carb either an HS4 or HIF38 with matching manifold will give a reasonable increase.
The easiest way if to get a combined mini manifold off a 998 engine and seperate the 2 halves as the exhaust is the same size as the standard Moggie one and fit a seperate alloy inlet manifold, it will still be restricted by the standard exhaust system but you will see an improvement.

[Peetee]

70 bhp from a 1098 will cost the earth and produce an engine that be a pain to drive in traffic because all the power will be at the top of the rev range.
You would be far better off making improvements to the suspension and brakes first and spending a couple of hundred quid on some bolt-on engine mods like those mentioned above. Choose wisely and you will have a car that has a modest increase in power that can be used far more frequently, safely and efficiently because of the better handling and brakes.

[bmcecosse]

Mods I listed for 1098 are not that expensive - exhaust would certainly be costly and only add the last 3 or 4 bhp. Head is dirt cheap, carb also v inexpensive as is MG Metro inlet - these are the main parts. As Kevin says - carb and inlet manifold change will be good for about 5 bhp and cost little. Add the head swap later!

[Kevin]

Morrisito so how deep are your pockets and do you know the direction you intend to go down.

[dunketh]

Simple 1098 mod?
Lift it out, dump it on your drive and drop in a 1275.

Thats not me being silly either. If you can find one cheap its probably the most worthwhile route given the cost of tuning parts and effort involved.

[bmcecosse]

Finding one 'cheap' is the tricky bit!!

[Morrisito]

Hello there,

Well, im quite tempted to keep my trusty 1098 and modify it! The size of my pockets depends on whether or not the people who owe me money pay me when they're supposed to!

It's a tricky one cause I know bugger all about mechanics but I'm willing to learn. I like the idea of getting to know things by making very simple mods and the idea of having to take out the engine with my knowledge is a bit daunting.

I'm in the process of installing a rev counter, oil and temperature gauge which I'm well into at the moment.

[d_harris]

I'm planning on spending come cash on a 1098 just to see what I CAN get out of it.....

However, a far more cost effictive route to the extra power would be to dump a 1275 in....

[MartinB]

Back in the late eighties I modified the 1098 engine in my Minor with the following spec:

12G295 head home ported with Rimflow valves, skimmed to raise compression ratio,285 cam,
single 1 1/2" Su with spindle halved/thinned etc, large K&N filter with stub stack mounted on an Oselli Torquemaster inlet manifold,
Rebored block & new pistons with PTFE buttons to stop the gudgeon circlips from jumping out,
Tuftrided crank, lightened flywheel,fully balanced, I can't remeber if I fitted a centre main bearing strap, probably but it was quite a long time ago!
Stainless LCB manifold and system,

This gave 65 BHP at the wheels and revved very well for a 1098, was clocked at 105 mph (on a private road obviously!) with Minor 14" wheels and the standard 4.2:1 diff with the Minor gearbox (no 5th gear here!), Was very docile on the road and not particularly cammy as I remember.

I tried it with a 40 DCOE but it but it then became cammy and very noisy, it was much sweeter with the single SU!

Then started to break gearboxes (teeth came off the input gear) and went the Fiat route.

Martin

[bmcecosse]

Sounds a great engine - would have benefitted from a bigger SU carb !

[linearaudio]

105 on a 4.2 diff? Someone clever please tell me what that equates to in revs, sounds quite busy!

[bmcecosse]

Probably about 7000 rpm! Although the '105' may be in some doubt!

[superchargedfool]

you are being given much good advice and the best bit so far was to get a copy of vizard's book.

It is the bible.