13 replies to this topic

[Midas Mk1]

Hey All,

Ive recently acquired a large valve (37/31) 21cc fully worked head, in preparation for a 1380 build that I had planned on doing in the next couple of months, ready for l2b + mitp.

Due to being really busy at Uni, im tempted to fit this head to my existing 1275, as an instant power boost, and currently weighing things up, as to what to do.
Its currently a pretty std low mileage 1275, kent 266, med itg induction and the usual stage one.

My question is, what other bolt on mods would you carry out at the same time, that are going to complement my new head? Ideally parts that could be potentially worthwhile on a 1380 too.

Im currently getting 77bhp atf with the current setup, and have to admit I love the 266 as a road cam, but just want something abit more. For the 1380 build im fitting an sw10, but if that cannot be built this year, then obviously the 266 will be staying in the 1275.

I was thinking (1.3 /1.5?) roller rockers + better dizzy suited for the spec?
Any thoughts or comments welcome

Cheers

Sam

[Artful Dodger]

Those extras will be good, 1.5 rollers though:) if needs must

[jackx998]

How about a lightened flywheel? I'd Deffinately change the dizzy and coil too.

[racingbob]

The car with the 266 like my mg metro is fine for me I wouldn't fit 1.5 rockers

Nice stage 2 maniflow manifold, electronic dizzy, flywheel not necessary with a 266

[jaydee]

Big valve -> high lift camshaft

[Spitz]

The car with the 266 like my mg metro is fine for me I wouldn't fit 1.5 rockers

Nice stage 2 maniflow manifold, electronic dizzy, flywheel not necessary with a 266

Bob....can you expand on that ( I know your referring to a light flywheel....not non at all..lol ).
Thanks

[MRA]

Lots of things are not necessary, however flywheels have been discussed a lot recently....

FItting 1.5:1 rockers (standard range from 1.22 to 1.28) will benefit the head, so will fitting a lighter flywheel, however what you will have is a car that has lost a little at the bottom end but gained a nice increase at the higher end, it will also rev higher.

The lighter flywheel being lighter will increase reliability, crankshaft and bearing life,
The lighter flywheel will increase acceleration, not by adding more power, as it doesn't do this, what it does it makes the engine easier to spin up.

Personally.... I would fit the 1.5:1 but fit an ultrlight flywheel in preference as the benefits are greater but that's my choice.

[jakejakejake1]

I personally wouldn't bother with the high lift rockers, I would rather spend the money on something like mappable ignition (megajolt etc), which will help you get the most out of the engine, and can be transferred to the new engine when the time comes.

[MRA]

FItting an ECU is a good idea, a fair bit more expensive though, but well worth it.

[jakejakejake1]

But when compared to the cost of proper roller rockers (not just high lift, non-roller rockers), mappable ignition is cheaper, will increase drivability and performance at all revs, all while making starting easier, increasing reliability and improving fuel economy.

Where as high lift rockers will give some increase in performance at high revs, but will lose you mid and low range torque. As Cooperman often states on the subject of high lift rockers, he gained a very small increase in top end power (<5bhp if i remember correctly) and lost power everywhere else in the rev range.

1.3 ratio rockers I cant argue with, but then again for the money are are better things to have.

[jaydee]

You must do some calculation of the proper lift and the valve size, otherwise is just guessing.

[mk3 Cooper S]

New Bypass hose

[Spitz]

I installed a light flywheel......instant and noticeable increase in acceleration.
I'm hoping Bob can explain why one isn't needed with a 266

[MRA]

But when compared to the cost of proper roller rockers (not just high lift, non-roller rockers), mappable ignition is cheaper, will increase drivability and performance at all revs, all while making starting easier, increasing reliability and improving fuel economy.

Where as high lift rockers will give some increase in performance at high revs, but will lose you mid and low range torque. As Cooperman often states on the subject of high lift rockers, he gained a very small increase in top end power (<5bhp if i remember correctly) and lost power everywhere else in the rev range.

1.3 ratio rockers I cant argue with, but then again for the money are are better things to have.

The cost of an ECU depends on who's you purchase, I use DTA and Megasquirt, the DTA is infinately better but a fair bit dearer as well

Its torque not power we need to consider, and the effects it has depends largely on the build being specified.