10 replies to this topic

[shed]

Hi

ive searched and cant find anything specific. at the moment ive got a standard sprite using a hif 38. all i want to do is add a stage 1 kit. so do i

use the hif 38
use a hif 44
use twin 1 1/4

as i understand it, a hif 44 would be better than the hif 38. but what about twins? if i have to buy something and need it setting up id rather have twins because they look cooler but not sure if twin 1 1/4 be big enough.

any ideas??

thanks

[samsfern]

twin 1 1/4 will be fine for a standard 1275, twin 1 1/2 s would be better though.

[bmcecosse]

My view is that twin 1 1/4" are LESS efficient than a single HIF38. Don't do it!! HIF 44 is the way forward.

[finch661]

i ditched my hif44 for a set of twin hs2's for my standard 1275, and its amazing. the low down torque is great and it feels more nippy. setting them up can be a problem, and take it to a rolling road.

pros of twin hs'2 = better throttle response, low down torque, they look cool in your engine bay
cons of twins = harder to tune if doing it yourself, requires 2X filters, needles...etc

oh if you get some carbs of ebay..etc.. buy a rebuild kit. saves a lot of hassle later on.

[Dan]

So you plan to buy a stage 1 kit and then throw half of it away to get a different carb? We seem to get a lot of similar posts to this, I don't know what exactly people think a stage 1 kit is but if the intake side is getting completely replaced, a kit is useless.

[Cooperman]

The original Cooper 'S' range, 1071, 970 and 1275 all had twin 1.25" SU's. The 997, 998 and Innocent Cooper 1300 (the last true Cooper 'S'?) also had twin 1.25 SU's. They all went well as history shows.
What Dan says about 'Stage 1 kits' is absolutely true. However, in the real engineering world of Minis the expression 'Stage 1' is more of a sales tool for suppliers than a true specification. A significant improvement can be made by fitting a better and correct size exhaust system including manifoldxhaust box(es), a gas-flowed cylinder head and, as you suggest, twin 1.25" SU's on a decent manifold (ideally not the original BMC thing). Of course, a better cam will be a great help when you next take the engine out. Twin 1.5" SU's won't be any improvement over the 1.25"s unless you do fit a really good cam when a lot more mixture is needed to cope with the higher revs needed to extract the power with a hotter cam, and even then the 1.25"s are OK up to and including the Kent 266 and its equivalents such as MG Metro cam.
With twins it is necessary to get them set-up properly, but once set they are great.

[AVV IT]

So you plan to buy a stage 1 kit and then throw half of it away to get a different carb? We seem to get a lot of similar posts to this, I don't know what exactly people think a stage 1 kit is but if the intake side is getting completely replaced, a kit is useless.

I don't disagree with this statement, I just don't quite understand it! Would you be able to elaborate on it a bit? Are you referring to him buying a standard kit with a single carb flowed inlet manifold, when he actually needs the twin carb version?

[shed]

maybe i couldve worded it better. im not going out to buy a 'stage 1 kit' from a supplier, i already have some bits needed so will gather the last few bits up as and when.

regardless, id still want to upgrade the carb so even if i did buy the whole lot from the shop id only have to change the manifold for the carb, not 'half of it'.

[finch661]

go for a set of twins, get a decent manifold (maniflow?), and new exhaust

[MiniLandy]

Vizardised twins.

That's what i'm going for! Do all the little airflow mods in the big yellow bible, stick a pair of K&Ns on there, and it should go well.

[Dan]

All I'm saying is that a stage 1 kit is just that, a kit. It's designed (or at least the better ones are, by which I mean the Mini Spares ones) for a specific standard engine to achieve higher tune. It consists of an air filter, an inlet, a needle, and an exhaust system. A stage 1 kit with none of the inlet components used, is an exhaust system. If you are going for any changes beyond the kit, you aren't going to get a so called stage 1 state of tune, you'll be beyond that into more custom tuning. I can't stand the whole idea of stages of tune in any case.

Stage 1 kit for twins? I don't think anyone does one.