HiWind

So prep began today in ernest for the new club season ... sharing for insight and comment as usual

Background: I sprint race once a month in the Provincial Sports & GT and in 3-4 National races with the Pro cars
(who are fewer these last few years and thus the invitation extends to any GT3 with certain times and
regular race experience and a current motorsport license).
Race weekends entail Mon&Tues evening prac for 2 hours - usually I use 2-3 10min sessions
dependant mainly on tire health - Friday official practice (ditto) and then Saturday quali in early am
followed by 2 classed (by time) heats. The final heat has random grid (within class). Races are 12-15 laps ie 15-20 min max. I don't enduro.

Plan for this year:
per the discussion on this thread which I almost hijacked my main concern is the ability of the engine to make it through the season
as a forced rebuild will be stressful, rushed and likely more expensive.

And because I plan to keep my 6Cup for a few more seasons at least,
a rebuild likely means a 3.8 or 3.9L and that requires lots of delicious planning
- a shame to rush it - and a new ecu or some hacker-genius who I've yet to meet.

Took the car for a quick 30 min session on the dyno with road (95 octane) fuel and got a strong and healthy chart ...
365 HP allowing for the 29deg c and atmos etc.. !3k kms and 100+ hours on the engine.

Bosch dyno so full atmos and temp adjustment etc.. Problem with one of the dyno leads re RPM so couldn't get torque (sadly)
but the key feature was a steady and upward sloping line with little turn off at the end, if any.
Likely means the engine could happily/safely convert an extra 400-600 RPM from its current 7800 top and make another 20-30kw.





Then we ran hot compression and leak-down tests.
All cylinders above 90% (92-93 hard to tell as guage goes 10-9-8 etc - all in the green area) ie very far within spec
and 12.4 or 12.5 on all cylinders re the compression - so happy days.
Per Glen's prior suggestion re watching for spikes, I aim to add a crankcase pressure light
which the 02+ ECU allows but isnt on the 01. Should help with early warning.


Checked coils and plugs and very little oil lost/used. A couple tiny cracks appearing on the coils (again ie had similar on the RS last yr)
but not broken thru yet. Plugs look clean and healthy tho 2 were a little loose.

All liquids to be drained, changed tomorrow - will take gb and eng oil samples mid-drain and send for analysis to set a baseline.

Only other notable points was the bumper seems to need a bit more heat shield on the sides re my muffler
which I added as track db spec dropped to 105 from 110 (i was 114).




Also took a bit of weight off while they had the bumper off


Parts on order/being added:
Revoxport FRP decklid mounted ram air scoop - en route I hope (Ken?!)
Rear wing uprights raised to roof heigh, under tray and front splitter (maybe)
Michelin slicks - arrived
Refinish BBS centres in Silver
Side bumper light heat shield

Long Term wish list:
Oakley style simulated seq
AIM dash
modern ecu
rear quarter windows with louvres - its hot down here!

Anyways, that's the plan so far .. I expect some of you can tell me how 100 hrs is problematic based on your (considerable) experience ...
while others might have very different opinions & experience.

Ahh, the beauty of rennlist - you decide for yourself after surveying the collective wisdom. Its what separates us from the Borg after all .

Hoping you all have a great season ... may you best times of last season be the worst of the next!

PedroNole

With your dyno numbers and leak/compression numbers, I think you're good for a bit on the engine. I would, however, at least change the plugs and make sure they don't over-tighten them. A $5 plug cost me $7,500 top end cylinder rebuild as the plug broke and a piece of it went through the head.... No Good! Change the plugs. Also, if the coils are the same that have been on the car for all of the hours you have on it, I would (a) replace all or (b) buy a couple spares to have them with you. I have had coils start to go on the 996 Cup at the hours you have on it.

I would also inspect the engine plug after each outing from now to a rebuild for metal. I would also change the oil after at least a couple of weekends.

HiWind

thanks Pedro. Plugs are perfect - clean and distances checked and fine. Snug & 1/4qtr turn to tighten.
As above, signs of cracks starting on two of the coils but still very thin ie mag glass to see them clearly.

Importantly I should correct myself above...
The leakage numbers were all 99%+ - I was mis-reading the guage ie 9 means 99 not 90% (see guage in vid) ...
which is nice

OlsenMotorsports

May I recommend a Shock Rebuild?? Just saying

HiWind

^^ based on?

OlsenMotorsports

How many seasons on the set of shocks that you have in your car? Every other year they should be redone for sure.... but the recommendation is once a year....

I am seriously thinking about doing a technical article on rebuilds... Many people dont send them in until they are leaking But I think many would be surprised what happens to the fluid and seals.... and it shows up on the dyno in a BIG way

Its kinda like having your eyes go bad gradually, you dont realize it until you put new glasses on!

HiWind

oh right - I thought you saw something in the pics. Good point though.
Are there a few simple tests worth doing?

OlsenMotorsports

not really anything visual or physical..... usually thats when they show up when the obvious things happen

Its all on a dyno.... i will do a write up maybe this week

HiWind

looking forward to it - thanks!

HiWind

Ram Air scoop arrived from Ken Cheung at Revozport.
Perfect packing, perfect fitment - thanks Ken! (and Antares for the ref)

flowbe

Is that a ram air scoop for a cup decklid ?

HiWind

it is .... http://s167.beta.photobucket.com/use...tml?sort=3&o=5

thinking of using windscreen glue to stick it on ... any other suggestions?

HiWind

here is the oil and gearbox analysis - seems ok for a baseline. Need to check the lb content of the race fuel.

Any others use this approach?

HiWind

Bump for any insight on oil analysis from the 911Jedi