46 replies to this topic

[GTIAlex06]

Basically, i have a basic 998cc with a stage one kit on it. I can't afford to convert to a 1275 or buy one.

buying a 1275 will work out cheaper than tuning you 998 past a stage 1 kit

Yeh but 998cc gives you extra smile factor when you blast past something much bigger than you

but thats not what this topic is about

Okay........

[big_pete]

getting it set up right is essential but some 998's are just faster than others, my mate's car is identical spec but is faster for some reason??

[MiniMonty]

I've just bought a pair of twin SU's for no other reason than I had some on a Spitfire years
ago and it sounded Grrrrrrrreat with a couple nice filters !

Don't think it'll do too much for performance (maybe a bit low down) but they'll be fun to have and
"balancing the carbs" was a Sunday afternoon ritual on the drive that I just liked.

[cap'n crunch]

I have just splashed out on a weber

its a 26/36, twin choke, double down draught one

just need to clean it up, and ill stick it on the 998

Be prepared to use a LOT of petrol and make noise but not a lot of power, maybe less than you allready have.

do you mean a 28/36? in which case Kudos! I have one on my 998 and it is amazing, in my personal opinion it is better than both a single HS4 or Twin HS2 and yes i have tried both. There is not much more noise than twin HS2, fuel economy is the same as my Twin HS2 though i do drive with a heavy right foot, but because it is a progressive downdraught I could easily get better ecomomy than my original SU's if i put my mind to it.

Back to the original question, To make a 998cc faster i would go for the following in this order

Freeflow exhaust manifold with Twin box RC40 Exhaust
12G295 cylinder head (or similar large valve 998 head)
1.3 Ratio rockers
And take it for a rolling road session.

If you want to go to town then...

Hotter Camshaft
Lightened Flywheel
Overbore
Mapped ignition or cutom advanced curve dizzy

[scotty_18]

Basically, i have a basic 998cc with a stage one kit on it. I can't afford to convert to a 1275 or buy one.

buying a 1275 will work out cheaper than tuning you 998 past a stage 1 kit

Yeh but 998cc gives you extra smile factor when you blast past something much bigger than you

Yeah it is good when you take someone off the lights or something, but i just want to make it quicker and acceleration to be quicker, then i can keep up with some of my mates and would be more fun to do rather than just buy a new engine or car.

[Retro_10s]

Please check where you are posting your threads....this was posted in the Styling section.

Moved to Technical.

[scotty_18]

Cheers for your help guys

obviously i can get a lighter fly wheel, what else can i do to the engine to make it lighter, like what engine parts could i get which you can purchase lighter??

[me madjoe 90]

just lighten and balance every thing crank (Knife edged sort of thing), conrods, flywheel, timeing chain duplex, not sure if you can get lightend pistons.

Get die grinder out and port it widen the ports. Cut/grind away any un needed metal from block and head that is left from casting. Add strengthend lightend ally bits and bobs. could drill your clutch bell houseing.


unless you are capable of doing all this your self will cost a bomb be prapaired to fork out (may be worth thinking how much you have to spend and the weighing up wether to put something bigger in) or could even go one step thurther for the money and put a red top in it or V-tec



faster - big valved head and lightening balanceing every thing, duplextimeing gear, Mega jolt it, twin carbs set up with right needels or a nice big carb. ported polished head get comperstion ratio right.

then rolling road and set it up right


gear box - striaght cut dog box , straight cut drop gears , LSD,

Edited by me madjoe 90, 09 February 2010 - 08:10 PM.

[bmcecosse]

The easiest - cheapest - and best power for bucks mod -is to fit a 940 head from a 1275 engine! Just sink the exhaust valves by 40 thou - and use a 1275 head gasket. Ideally - a good exhaust - and an MG metro inlet manifold with an HIF38 carb, and it will fly. If you can manage an MG Metro cam - and an HIF44 carb - it will really fly!

[Gr4h4m]

boost.

[Mini_city10]

i got a respectable 62BHP out of my 998 with only a stage one, unleaded head (of unknown origins) and a very retro nikki twin choke carb. that was a good little engine.

whats ur fuel consumption like??

[Mini_city10]

i got a respectable 62BHP out of my 998 with only a stage one, unleaded head (of unknown origins) and a very retro nikki twin choke carb. that was a good little engine.

whats ur fuel consumption like??

[smtaylor3]

this all good stuff im planning similar thing to my 998

[liirge]

How much modification has to be made to fit the down draught? im guessing there has to be some type of bonnet bump or something, or can you just raise the back of the bonnet, like I've seen, and get away with it?

[PhilipGCaldwell]

plans for my 998:

Fit reworked 12g940 (have worked on the valve throats around the valve guides alot)
fit SW5 07 Camshaft (with dublex vernier)
fit twin hs2 with 1.5inch ram pipes, with twin K&N cone filters
eventually fit lightened flywheel

She currently has stage 1 kit with lcb and fletcher 2.5 inch exhaust, and electronic ignition. RR said 38 bhp atw
Im expecting after the mods to be 55-60 bhp atw