Engine musings.....

[TomB]

Just pondering what I could do next to my K series engine for relatively sensible money on a boring Sunday night while other half is watching the Olympics. 

Currently, the engine is a an EU2 1.8 Supersport, with stock bottom end built up by Oily and a K16 head. It has SLR/KV6 throttle bodies, a 4-1 long primary exhaust, Emerald ECU, vernier pulleys and lightened flywheel. When it was mapped a couple of years ago is came in at 149bhp. 

So I've a reasonable set up that I could add more power, without having to buy TB, Emerald & exhaust. Thus I'd hope I would be able to limit cost at this point. What would be a sensible way of taking power up to around 170-180bhp, whilst maintaining road friendly, tractable delivery? 

I know the stock pistons are limited, but could they take 170-180 if engine speed was limited by the ECU to something like 6800? Would the bottom end be strong enough? Would fitting stronger pistons, forged Omegas or Trophy 160 be the logical start point and build from there? 

For the head would finding a VVC head and converting it for solid cams and simply(?!) fitting on the existing block be a fairly simple bolt on upgrade? 

Whilst thinking about it, would the standard 5 speed and Sierra based LSD cope with the extra power? Or have I reached the end of a cul-de-sac based on drive train and piston limits without upgrading several key parts? 

[Jonathan Kay]

Are you already familiar with DVA's thoughts and options:

1. K Series
2. Upgrades?

Jonathan

[TomB]

Yes, but in the case of 2), it doesn't really help me as I already have the various components of several kits (eg Emerald, TB). I think I need to fit Pistons as a first step, but it's full rebuild, rather than 'just' bolting on a breathed on head so much more involved. 

[oilyhands]

A piston upgrade can be done with the engine in the car and doesn't require a complete rebuild.

180BHP at 6800 will be a challenge. You will need more RPM than that.

Oily

[TomB]

A quick run thought the piston change - is it head off, sump off, bottom ladder off, unbolt bottom half of big end/rod, push out of the top? 

So Omegas are well established, what about the rods? Are standard adequate? 

[Wrightpayne]

Tom,

cams and head porting followed by a remap. I think the pistons are a must - i'm still to get mine done but its next on the list.

Drive train is fine - there are lots of 200+ bhp vauxhalls out there. Considering all the upgrades to my car the 6 speed box is one of the best - it transforms the car!

Ian

[TomB]

So as the head would have to come off for porting, it would make sense to fit the pistons whilst half the engine is apart.  Im not sure it would make sense to change the pistons and refit the existing head as it would all need to come apart again for any future head work. 

[Mankee]

I pretty much started with what you currently have: ~150bhp, ITBs, decent exhaust, mappable management. I went to ~200bhp by keeping the induction, exhaust and ECU and slapping the lot onto an eBay VVC 160 engine. Bottom end was untouched as it had the VVC 160 pistons and all the money was spent on the head: porting (~£500-£600) and binning the VVC bits (can't remember exactly how much; DVA will advise depending on if you want springs and caps, another set of verniers etc.). Plus a few hundred quid on mapping.

The beauty is that you'll still have your complete existing engine and map to fall back on if anything happens to the new engine. The problem is finding complete, good VVC 160 engines as a starting point nowadays. They seem to be getting very rare now.

[oilyhands]

THe stock rods are fine with Omegas but will need bushing or honing to accept the pistons fully floating as the interference fit cannot be re-used safely. If you existing liners are serviceable they will need glaze busting with a flex hone or similar.

Oily