11 replies to this topic

[Chew]

Hi everyone, just wondering what a good 998 build would be (intended for almost daily use so main areas of the engine will be replaced and won't be put together for at least another 1.5 years due to insurance and other bits needing sorting out)

 

Currently I'm 18 and would like a bit more power. My reason for going 998 is that I already have a 998 and 1275's seem to be going up in price (currently trending at about £400+ on ebay). The build would have to be somewhat economical (MPG wise) and not too expensive (£1000-1200 max, already have a stage one kit fitted).

 

Cheers.

[blacktulip]

There are plenty of great 998 threads on here, have a good search. If you are handy with the tools I would suggest a swiftune sw5-07 cam with a suitable modified head plus a good session on a dyno will be the way to go. Speak to AC Dodd on here, he will point you in the right direction.

Edited by blacktulip, 23 October 2017 - 07:27 PM.

[Cooperman]

A word of caution first if I may. It is easy to spend a lot of money on a classic car engine and not really get much improvement. You are dealing with a 60-year-old design here and it will never go like a much less expensive modern car. Classic Minis are really for a 1960's 'retro' driving experience.

 

Now for the 'techie' bit. The key to better performance with any A-series engine is the cylinder head. It needs to be properly gas-flowed with the compression set to around 9.75:1. Then a better cam, a re-bore and new pistons, an HS4 carb, a 3-into-1 tubular exhaust manifold and a decent silencer system will make it go a bit better.

 

Build it very carefully and accurately and you may well get the bhp up from around 34 to 45+.

When increasing the power and torque you must ensure the gearbox is in top condition as more 'grunt' will soon show up any wear in the gearbox.

I think a budget of only c.£1000 is a bit low for what you want to achieve, even with you doing all the work yourself.

 

A classic car of any type is not entirely suitable for daily use and when my Grandson was 17 he had a fully and comprehensively restored Cooper 1275 MPI, but soon tired of it on a day-to-day basis and bought a 1.25 Fiesta Zetec. Of course, he is able to drive my cars, including my 1275 Cooper 'S' so he is not Mini-less.

 

Good luck with yours. 

[Chew]

A word of caution first if I may. It is easy to spend a lot of money on a classic car engine and not really get much improvement. You are dealing with a 60-year-old design here and it will never go like a much less expensive modern car. Classic Minis are really for a 1960's 'retro' driving experience.

 

Now for the 'techie' bit. The key to better performance with any A-series engine is the cylinder head. It needs to be properly gas-flowed with the compression set to around 9.75:1. Then a better cam, a re-bore and new pistons, an HS4 carb, a 3-into-1 tubular exhaust manifold and a decent silencer system will make it go a bit better.

 

Build it very carefully and accurately and you may well get the bhp up from around 34 to 45+.

When increasing the power and torque you must ensure the gearbox is in top condition as more 'grunt' will soon show up any wear in the gearbox.

I think a budget of only c.£1000 is a bit low for what you want to achieve, even with you doing all the work yourself.

 

A classic car of any type is not entirely suitable for daily use and when my Grandson was 17 he had a fully and comprehensively restored Cooper 1275 MPI, but soon tired of it on a day-to-day basis and bought a 1.25 Fiesta Zetec. Of course, he is able to drive my cars, including my 1275 Cooper 'S' so he is not Mini-less.

 

Good luck with yours. 

I've seen that 12G295 heads are popular but what would the recommended compression ratio be and what would the max fuel octane be for suitable use? I can't really find a definite answer.

[Cooperman]

A 998 will run well with a C.R. of between 9.75:1 and 10:1. 95 RON petrol should work so long as the timing is set accurately, although 97 RON might be better.  

 

The 295 head is great, but you will need flat-top pistons for it to work well, especially when it is fully-gas-flowed.

 

You are unlikely to get a 295 head, plus a set of flat-top pistons, a new cam & followers, oil pump, timing chain, big-end and main bearings, new clutch, valve guides and valves and all the gaskets, etc., for much less than £1500 with the necessary machining. Then allow around £700 for a full gearbox build. For a full re-build you do need to allow around £2000 inc. gearbox if you do most of the work yourself.

 

Engine re-building is never cheap on a classic car. That is what classic car ownership is about really and is why a modern is so much cheaper and easier to live with than a classic of any type. Most owners keep their classic for weekend fun, shows, etc.

[WillCarter]

All the mods you do to the engine need to be declared on your insurance which might bring the price up depending on what you do to it. Id get a quote on your insurance with all the mods youre wanting to do first so you know you can afford everything.

I dont mean to put a downer on it but Ive know someone who had their insurance made void. It will make any future insurers very unlikely to insure you without paying £££££!

Edited by WillCarter, 23 October 2017 - 08:24 PM.

[Avtovaz]

so your 18, you have a mini you probably dont have much money...

 

 

I was the same, i had a 850 mini when i was 17-18, then when i phoned the insurance, it was the same price for a 1100 engine!

 

I went for a 998 as we scrapped a car with one in. It had a 1275 head, it went well.. [and yes i told them]

 

From owning a mini and trying to get it to go faster, is how i got my job now building tipper trucks.

 

Tune it, learn and anyone on here im sure will help... Even getting 2 bhp more is worth it!

[dotmatrix]

modifying a 998 is fun and can give good power. I have a metro with an a+ 998 engine in one of my cars with flat top pistons, a 1275 head, kent 266 cam and a modified dizzy everything else is standard. The result was 65bhp at the crank which is great, But it isn't much faster if at all than the same car would be with a good 1275 in it.

But my advice is buy a good condition 1275 and give it a light restoration. It will be easier and have a much greater power potential.

[Avtovaz]

probably correct but at his age, how will he insure that?

 

 

But how do you know about the love of , this now feels better, oh that lost a bit, and if i put the dizzy a bit more that way , etc...

 

Dont over complicate it, just tune what you have , go and have some fun!!!

 

 

At 18, learn to drive a 998 first and enjoy putting that low power to the road down..

 

 

that is why in my mini advantage, ill be putting the 1275 away and doing a few mods to a 998.. Learn to drive it first and learn enjoy it...

 

 

keep the 998 and put  the 1275 money into setting the suspension up... And fool can make a drag racer.

[panky]

Who was it who said - the best way to make a Mini go faster is to sort out the handling. Someone on here.

[cal844]

Who was it who said - the best way to make a Mini go faster is to sort out the handling. Someone on here.

I agree with that statement and also agree that it was said on here

[Cooperman]

I think I was one, probably of many, who said that the idea of modifying a car is to make it faster.
The way to do this is to first of all make sure that the brakes are at their best.
Then improve the suspension by fitting new bushes, solid mounting the sub-frame, adjusting the camber and caster angles are at the optimum and fitting better dampers.
That way both the road-holding and handling will be at their best and it will go around corners quicker and safer.
Top brand tyres of no wider than a 165 section should also be used.
Only then is it worth spending money and time on significant engine mods.