6' Engine Upgrade Options

[p1234 22 2 Cars]

Im doing a re-build at the moment on my Gti6 and was looking for some guidence on engine upgrades,

 

I have a polished head with 3 angled valves, pt81's (bought from Miles), T/b's and an emerald.

 

What type of bottom end work would you advise and will I get the power im looking for from these cams?

 

Car will be used for Rallycross, budget isnt huge but going to be putting this together over the next couple of months.

[welshpug 1,662]

pistons to make the most of the cams, and a decent inlet manifold.

[p1234 22 2 Cars]

Forged pistons and rods, keep the pt81's?

Edited February 14, 2012 by p1234

[petert 591]

The PT81's are borderline with the standard pistons anyway. Either buy new ones, or deepen the pockets.

[tommy gun 6]

what power are you after?

[p1234 22 2 Cars]

Looking for a reliable 240.

Edited February 23, 2012 by p1234

[Anthony 1,003]

Looking for a reliable 240.

With PT81's? No chance IMO. Probably more like 200hp or so.

[welshpug 1,662]

Not far off the mark there Anthony, I know of two on standard inlets and mapped ecu's rinning 194 and 193 respectively, RR bhp of course.

 

torque was around 160 lbft on both.

[petert 591]

240hp from 1998cc? Your reference has to be the Cosworth BDG which makes 240hp @ 8000rpm. It does this with cams that have approx. 250º duration @ 0.050" and 0.150" lift @ TDC. Sorry, but you need 12:1 and big fat solid cams.

Edited February 23, 2012 by petert

[welshpug 1,662]

3.81mm @ TDC and 250 deg @ 1.27mm, quite fat then

[p1234 22 2 Cars]

Thats why im asking the questions lads,

 

Ditch the Pt81's so,

 

Is 240 an unrealistic target for a 6?

[welshpug 1,662]

not at all, top end versions are over the 300 mark, but to make that reliably is not cheap.

[rallyeash 155]

does it need to stay 1998cc?

[p1234 22 2 Cars]

No I can go 2.1/ 2.2 if its a more sensible route,

 

I wouldnt see the point in building an engine thats not reliable for what it will be used for,

 

Now is the time to build it right so costing that bit more now is not an issue.

Edited February 23, 2012 by p1234

[welshpug 1,662]

240 is acheivable from a well thought out 2.2 with quite mild cams.

 

DrSarty's is a good example, though was an Mi16 head; standard exhaust cam and a peter taylor inlet cam, colin satchell inlet and mapped by sandy in its last incarnation, 240 bhp 190 lbft IIRC.

 

Djmini's is a build by sandy which went to 280 I think.

[p1234 22 2 Cars]

Well thought out is what im after, just dont have the thinking skills myself

[harryskid 193]

Your going to need very deep pockets !

[p1234 22 2 Cars]

Ha ha, I might stick with the stockhatch yet, 20 quids go-go juice and all smiles for the day!!