"Mild" competition engine build - thoughts please

[kiwiclio]

Hi from New Zealand - the situation: broke #4 exhaust valve, took out the piston and so heavily scored the block that it's new engine time. Have sourced another Ph1 172 engine with eqiv. of 40k miles on it here in New Zealand. The car: Ph1 172 dedicated to tarmac rallies (150 miles a day of hard-out on special stages with 2 or 3 times that at normal road speeds touring between stages). Work on the old engine had been mostly on intake & 'externals' - ITBs with Link G4 engine management and stuff like A/C delete, uprated coil packs, leads, water hoses, catch tank etc. Had reprofiled cams to emulate CatCam 421s. Was running ~180HP at the wheels.
With 'new engine' options range from dropping in exactly as is (freshening waterpump, cambelt etc of course), putting ITBs on etc - to an all-out build. What I want to do is strengthen the engine without spending a fortune - i.e. don't want another broken valve, etc...immediate thoughts were to out in uprated valves and springs alongside a genuine CatCam, but not the forged piston/rods route given cost and goal is not power per se...

Anyway - would appreciate all thoughts as well as anywhere for parts in addition to K-Tec.


With thanks,
Martin

 

[Matt W]

Awesome number plate.

 

[Fred@BTM]

set of one piece valves and forged pistons would be my vote, don't worry about the rods, perfectly fine for NA (fit ARP rod bolts though)

we can supply no bother, as can many others, RS tuning, Trackgroup etc etc

 

[JackJack]

Do valve springs need upgrading Fred or are stock strong enough?

 

[Fred@BTM]

depends how mad you want to go, we ran stock ones without issue

 

[mark123]

What CR can you go up to?

 

[Dan519]

Stock rods, ARP bolts, Supertech 1 piece valves,

Catcams 421's with stock compression/standard pistons
422's or 423's with raised compression/forged pistons

 

[Iceberg_172]

Link G4 ECU!

nice

 

[kiwiclio]

Thanks Fred and Dan - seem united on uprated valves and head bolts...question then is stock vs forged pistons (and related camshaft)...I'm no techy so what would raised compression mean for the rest of the engine? (i.e. Wossner pistons seem to be 12.6:1).

Replacement stock engine has arrived - so any other input very much appreciated as will have to make some decisions soon about what and from whom...

With thanks,
Martin

 

[Dan519]

not headbolts, Conrod bolts. Headbolts are fine until you start with high boost and Nitrous.

 

[BRT Motorsport]

hi exact thing has just happend to me, pics here http://www.cliosport.net/forum/showthread.php?609513-R.I.P-Engine.-What-to-do-next-Help-appreciated./page2
i also had standard engine with cams and throttle bodies

 

[kiwiclio]

Thanks PROIL for the link to other comments - yes, absolutely identical - I had oil sprayed out of the #4 trumpet (valve let go at about 7,000 RPM down front straight of local track...) and once tb removed the valve base stared at us from the cylinder head...will read over lunch and may PM you as with rally car probably some useful experiences!
Cheers - Martin

 

[Laine_16v]

hi exact thing has just happend to me, pics here http://www.cliosport.net/forum/showthread.php?609513-R.I.P-Engine.-What-to-do-next-Help-appreciated./page2
i also had standard engine with cams and throttle bodies

How uncanny, i did exactly the same thing too, on a standard engine with cams and throttle bodies lol

If i ever add cams again i will use 1 piece valves

 

[BRT Motorsport]

yes no problem martin, if your looking for a cheapish option i would go for standard bottom end cams and the one piece valves!
ours was standard engine with cams, vvt removed vernier pulleys and head work and we got 203bhp at the wheels
think i will go for pistons and rods for a bit more reliability

 

[mikekean]

Stock rods, ARP bolts, Supertech 1 piece valves,

Catcams 421's with stock compression/standard pistons
422's or 423's with raised compression/forged pistons

What sort of RPM's and power will Stock rods take?

 

[Fred@BTM]

8krpm+ (with bolts, but i wouldn't trust the reliability 100% at that) + 240 beans

 

[Meek_racing]

What sort of price for one piece valves? If it's nothing to costly, add that to our quote please

 

[Jay Payne]

 

[Silent_Scone]

Given that was taken only a few days ago... you going overhaul-mode next year Jay?

 

[Jay Payne]

Well you know we have to build a new engine after ours went bang at oulton. Not exactly a secret. Yes we are using Supertech 1 peice valves

 

[Silent_Scone]

well yeah, meant more in the upgrade sense lol

 

[Jay Payne]

its being built for reliability. so ARP bolts etc.

Ive had sevrral pm's now about the valves. ask dan @519 about them