8 replies to this topic

[Sutty01]

I WAS JUST WOUNDERING WHAT PERFORMANCE PARTS I SHOULD ADD DURING RE-BUILD LIKE WHAT SPRINGS .ECT?

NEIL

[Sutty01]

eny one ?????

[Bluemini]

Uprated or double valve springs, with less coils so they dont crush with high valve lift (bent valves else), adjustable timing chain is handy for gettin the new 276 cam all timed in nice. If you want to squeeze a bit more from the engine without too much expense, get the head skimmed, i normaly have a 60thou skim, raisin the comp to bout 11 - 11.5 : 1...

Other than that, without a major re-build with new pistons and over-bores, a good intake and exhaust system is a step in the right direction.

[Sutty01]

i have stage one and i got k&n so im ok in that spect can you explain what diferance dubble valve springs will make?

thanks neil

ps go on msn lol

[Bluemini]

If you rake the tits out of your engine, you'll get valve bounce at high revs, doulbe springs are stronger than normal springs, and help stop the bouncing and also help close the valve quicker and tighter...

[Pavel]

doc, can you help me get more bottom end power out of my engine? I'm quite literate about engines and improving performance, but almost everywhere everybody tries to get it no matter at what RPM...

I would like some more torque down below (and not through a diff as I still need to cruise in it).. any ideas?

[Bluemini]

Not wanting to offend any people who already know this stuff, but this is intended a bit of a guide for less experienced people

I've got a mate with a boggo 1275 and it is fast as hell, was all over old blue and that had loads of mods, just a home made exhaust and a K&N. This is jus because he had a nice, well put together engine!

The chances of comin accross an engine like that, specialy were you are is pretty slim! So i recomend you start by (if you havent already) changing the flywheel for an early pre verto type. These are lighter than the later type by loads, and thus producing better excelleration, and tho they may be a little primative, there is the bonus of being able to adjust the clucth manual.

The next thing i would look at is the head, gettin the fuel in and fumes out is a major part, but on top of this a good combustion is also the key. Even if you dont have a ported head or any fancy stuff for it, get it skimmed by 40 or 60 thou and get the compression up.

Following that would be a change in cam. The Kent 276 is a good cam, gives good figures without compromising drivability of the engine, but this would be an engine out affair.

If your feelin a bit flush, then invest in a set of 1.5 roller tip rockers, they are excellent, instant bolt on power right through the revs!!

Lastly would be to look at the engine and 'box. a change of diff will give different excelleration/top end charactoristics as you know, but as for as engines go, I would recomend a 1293. It gives that bit more alround power, without the unreliability of a big-bore block.

[Pavel]

Hmm, i new almost all those mods but thanks anyway!

A 276 cam will push up the revs which is what i DON't want.

The head skimming however sounds good to me.

Basically here is the deal, me and my dad got a 850 engine disassembled and a 998 engine complete with gearbox but without flywheel cover and starter motor and dizzy etc. small things. They are both free.

We want to build 1 good engine between them. we're gonna strip it down completely and rebuild from the bottom up. This isn't to renew the engine or to get power out of it. It's simply so me and him know how to take appart and put together an engine.

However, if the engine turns out to be in good shape, I'll want to use it, but will want it to have more 'pep' for as little money as possible! 1.5 rockers are unreliable and they cost WAY too much. I'm probably gonna go with an MG cam or a SW5 as those are good and torquey!

Thanks doc

P.S. how much does it cost in UK to skim a head? (cylinder head )

[Bluemini]

Bout £30 ish lol