Monday, September 07, 2009

Wanneroo Sprint Piccies

Sunday, September 06, 2009

New Bits for White PI Part 2 Cam change

Old Wade cam out through the nose cone. Essential mod for modded Mk1's !!!! Cam was definitely on the way out. Exhaust 1 lobe about 0.220" whereas standard for this cam is 0.265". All the otheres were between 0.248" and 0.255" and showing signs of distress especially on the lowering flank.

New cam with polished journals, nicely scrolled on these early TR5 cams.

Not sure if this is really necessary on a tuftrided cam but it won't do any harm either

Installing the Cam and timing up with Inlet lobe 1 at max lift with engine at 108 deg ATDC.

Been cleaning up a spare old PI head 218225 (32mm exhaust valves) for possible modification with GT's valves if it passes the crack tests.
This will have to wait 'til Thursday as I'm off to the gold mine, then I'll cart the heads to Luigi's Head Shop for the next plan of attack. Right now I have six hours before I have to wake up for the flight.. yikes...

Saturday, September 05, 2009

New Bits for White PI Part 1 .. Strip down

Reground TR5 cam using hybrid inlet / exhaust cam profile. Inlet is longer duration than exhaust and seems to give big torque and bhp. Tuftrided.
Excellent cheap alternative to most Triumph tuning junk. XJ40 valve springs. Cost peanuts and very adequate for Triumph cams and valves

New GT inlet and exhaust performance valves. Nitrided steel and stellite tips and exhaust valve seats

I have decided to freshen up the top end of my White Mk1 PI as it seems a bit down on top end power compared to Humph's freshly built PI.
Head off for the first time in seven years

I have got a new hybrid camshaft very similar to my mate Humph to try + some new Gareth Thomas valves to build into different head and a set of hybrid Goodparts Roller Rockers of 1.65 Inlet and 1.55 exhaust compared to my current 1.65:1 ratio set.
Flowed head running 10.75:1 CR and Chris Witor Big valves ... probably keep this complete but probably wont be using it on The White thing again

I will also be using the recently discovered mod of Jag XJ40 springs which look very good quality - are not too hard on cam lobes and cost the princely some of about 80p each from Jag Genuine Parts!!!
Buggered cam folowers... guess the cam (Wade 444C) will be a bit secondhand too judging be the look of these.

Stripping down the head from the Pi for the first time in about 7 years was a fairly easy process. Got it all off in about an hour. First suprise was that the rather crap Racetoration stainless head nuts were almost finger tight, certainly no more than 45lb ft so they will be consigned to the bin. Obviously have lost their torque and Stanparts finest will be going back on... what was I thinking back in 2002!!!!
The head slipped off easily revealing a mint set of bores... nice suprise considering the revs and abuse this engine gets. No scoring or ridges at all and honing cross hatch still easily visible.

Considering the lack of torque on the head the gasket looked perfect with no sign of any overheating or blowing. Not suprising really as it it was running really well apart from missing a second from it's ultimate lap time.

Whipped out the cam followers and the first sign of wear. 4 or 5 showed serious signs of surface hardening picking up so I expect the cam to be fairly secondhand once I get it out tommorrow.

Looks like the new cam might have more effect that I had hoped for .... EXCELLENT......

Tuesday, September 01, 2009

TSOA Wanneroo Sprint

Fun day with beautiful weather.

Humph was using his freshly re-cammed 2.5 and I was testing my new brakes. We both ended up with good results and both have things to improve

We both got PB's on the short circuit and Humph just pipped with his new found bhp on the long circuit... time I fitted the same cam plus a few more head mods I think as my Pi is a little off the boil bhp wise after 7 years hard use.

There were a few casualties including the 2.5PI saloon of Paul Dodds dropping a rod which was a shame as it has been improving fast.

Good fun to be competing with the Westfields and PRB Clubmans (Caterham copies) and an supercharged Exige (which was obviously driven pretty conservatively!)

My brakes weren't quite right so a change of disc diameter and pad material beckons + some cooling ducts. I will be trying 296mm DBA Skyline discs (currently 280mm) and Ferodo Ds2500 asap