33 replies to this topic

[1977 Loud_Mini]

Hi everyone, as i have a completely standard 998cc engine in my garage which is an early engine with pre verto clutch and the longer reach type alternator bracket. So i was thinking of building a quick 998cc engine. I would ideally like it to keep up with a Rover metro GTI 1.4 SPI 16v and a citroen saxo VTR 1.6 8v, what setup would i be looking at to keep up with these cars if it is even possible without a turbo.
A couple of people on here have opted for the 1061cc overbore and i was thinking of the same or possibly a bit higher, only downsize is the walls of the bore will be getting very thin therefore more vibrations etc etc. I would like it to rev fairly high, my 998 in my mini at the moment is slightly modified with 12G295 head, 1.3 or 1.5 roller TITAN rockers, uprated timing chain, electronic ignition and that revs to atleast 6500 or even 7000rpm. It has a lumpy tickover so could have a good cam in it.

If anyone has any recomendations then that would be great.
Thanks, Evan.

[leaky]

Its up to you mate. But. It really is quite pointless. I have a quick 998. Its been pocketed and got a 1275 head on it as well as a stage one kit. I bought the mini with the 998 and the 1275 head but it hadn't been pocketed so I sent it off to an engine builder to get it sorted. It cost me a few quid under £800. At this point I didnt really know anything about minis. If I had known more about minis and how much this would have cost I just wouldn't have bothered. I would have just got a standard 998 head or a 1275 engine. My 998 now keeps up with 1275's but cost me more then an 1275 would have cost. So it was really pointless and a massive waste of money.

Edited by Mini-jon, 27 June 2010 - 11:09 PM.

[1977 Loud_Mini]

Thanks for the reply Mini-jon. £800 for pocketing the block, does it really cost that much? I have been wanting to just get my 998 overbored and keep the 12G295 head etc and see how that goes, possibly get the crank assembly balanced and a balanced flywheel etc. I was also thinking twin hs2 or hs4 carbs as i don't really want to be cutting the bulkhead for a weber (i'm sure there is a short manifold so that you do not need to cut the bulkhead). I'm not sure what sort of power i would be looking at with this setup but if its a little bit quicker than it is now i'll be happy. I know Racer Pete on here a while back was building a 1061 engine.

[1293sleeper]

The metro has a very quick engine so does the vtr both topping 100bhp best bet if you wana keep the 998 is a overbore a good high cr head and a 266 cam with twin hs2s and to lighten the crank,con rods and flywheel and then to lose as much weight from the mini as possible. Plus get the best suspention you can afford and a good set of yokos They will still beat you on the long straights but bends and off the lights you would have the advantage.

[minivanman]

waste of time. the money and time you spend on a 998 you could just as easily throw at a 1275 and have twice the power and driveability. I know, I've tried it!

[1977 Loud_Mini]

1293sleeper- that sounds like a nice setup, just to beat the cars off the line and hold them for a while would be great. It would be nice to say you've just been beaten by a 998 (well basically 998 even if its overbored ).

I wouldn't mind getting a 1275 and doing a bit of work to that for performance gains. I can get a very cheap MG metro 1275 engine. I just like the idea of having a quick small bore engine capable of producing a relatively large amount of power.

[1293sleeper]

If you want to do it mate do it. Of coarse a 1275 will give u more power but I know people who race mini that preffer a well built small bore to a big bore any day of the week. The way I see it is build the car for yourself and not how every one else is doing it. My friends overbored 998 has embaresed a few abig bores in its time u just have to know how to use it.

[CHUNKY365]

Do it!

Don't listen to all the chumps who insist a tuned 998 is a waste of time and money.

The 998 is quite tuneable for quite good money.

You don't even have to mess about with changing cranks really.

For good useable power a 998 is great, it'll take the revs and a lot of abuse on the road (mine does)

It'll keep up and even embarrass a lot of the 1275 (and bigger) engines.

You don't have to spend fortunes on it, just choose what to do wisely!

Remember, the 998 has been around a lot longer than the 1275 and more poeple have started their tuning careers, by using the 998.

The blocks are plentiful and cheaper than the 1275.

And the 998s are far more reliable!

[george91]

well it depends how much you really want to spend, i've heard of n/a 998s pushing 100hp but it comes at a price as thats going to be basically a race engine, and it will be a PITA to drive at anything besides flat out, i guess if you don't want to spend an absolute bomb expect to either use a 1275 or forced induction or both for the best results, turbo guys are running anything from 100bhp to 200bhp+ so for the top figures turbo is probably best.

Edited by george91, 28 June 2010 - 12:25 AM.

[skaterava]

I'm swapping my 998 out for a 1275 as soon as a cheap one comes along. 998's are good, but you can't argue with extra engine capacity. I've got a Stage 1 kit fitted but it still doesn't cut it for me, i want to have a Mini that will beat most similarly engine-sized modern hatches (1.2 Corsas etc) off the line.

[JakeJakeJake]

If you want a 998 then go for it, its nice to have a small bore that is faster than much larger ones. However there is no denying that larger bores are cheaper.

Have you considered a supercharger? this graph is for a completely standard 998 that has been supercharged:



Would stretch your budget but add a better head, cam or high lift rockers and better exhaust and maifold and you should be there

[miniman92]

Personally, a well built 998 motor is much more fun. My 998 has 70bhp, but basically it has 998 block decked 20 thou, a fully worked 12g295 cylinder head (35mm Rimflow inlet valves & 29mm exhaust valves), kc 276 cam, forged s rockers, fully lightened and balanced bottom end, ultralite med flywheel and backplate, sc drops with close ratio GT gearbox and central oil pick up pipe amongst other things. My dad drove my clubby estate a few weeks back that has a metro gta engine just rolling roaded at 75.5 bhp at minisport, and trust me he couldnt lose me in my 998 once it comes on cam, I was pushing him up the hills!

Despite this though, a 1275 metro engine can be found for £350 and they are brilliant and make good bhp and torque, just depends what you prefer.

[1977 Loud_Mini]

Thanks for all the help regarding tuning of the 998 and 1275 engines. I do have a slightly modified 998 at the moment so i thought why not go for something a little bit more lairy and overbore it to around 1061, get the 12G295 re worked, twin carbs, cam etc and see where that takes me.
Its encouraging to know quite a few people on here have 998's boasting big specs and that do give good power outputs.

I haven't really considered a supercharger as this would be a relatively expensive addition to any engine.

miniman92 - are your BHP figures at the flywheel. Also if you don't mind me asking how much did that setup cost you?
As i mensioned previously i can get my hands on an MG metro 1275 which i probably will in time purchase and then i can slowly build up a 998 in time.

[mars red mike]

To be honest mate you will never be able to tune a 998 enough to keep up with Metty GTi's or Saxo VTR's. If you want to build a nice quick 998 then do it by all means but if you are hoping to keep up with the likes of GTis etc you are going to be disappointed.

[JoneseyBoy]

1st things 1st get what theycall the bible lol tuning the a-series engine by david vizard he has a enigne build he did on page 468 and said it woud beat any standard 1275 s engine and what the same 0-60 time as a mertro turbo but his was only 75bhp wich to be honest if he could of got more out of it then he would have so to be honest i think your aiming to high with the 1.6. im going down the same route tho as i think it would be better to say yer i have a 998 and im hitting alot higher than my weight but all ive done is put a bp270 cam in and looking on putting stage 3 head on or a 12g295 well modified head. but after this i want to build another one but blue print it if you dont know what it is its pretty much taking as much weight out of the engine as you can, lighten everthing get it bore to as far as it can go but with this ssrt of thing it gets really expensive and you have to keep reving it when stand still as there is not enought weight on engine parts to keep it spinning