Sunday, May 28, 2006

Major Breakthrough! Schumi to the back of the grid?!

Don't care how you read Schumachers "mistake" thats just complex boll****. A good race ruined, so much for my Sunday fun, who wants to watch the spaniard walk another challengeless race, goddamned stewards!!! I am furious!!

Well my engine is certainly different to the old one!

The old one needed a 50idle jet to get a crisp light throttle cruise to 3750rpm. It needed a 112main on a 7 tube with 150 corrector. I assumed the new engine would need atleast 50idle and maybe more to make up for its extra cc and compression, but the opposite is in effect. After fixing the float issue I left the garage this morning on a cold engine and it ran really well on the 50, then once temp rose to 70C it ran like a dog...

Which I thought most odd. So I changed to a 48idle which was lean on the old motor, now its super dooper at cruise and town work is clean but not perfect. I think it needs 47 now but I have none! Screw useless Webers, Dellortos are the NUTS! 0.01mm jetting changes DO make a difference, a big one, on a Weber a 5 point change at time is utterly useless.

Reason for this can only be put down the engine having much more draw on the venturi tube, increased signal strength= the main jet is now on earlier and overlap is less in length so the smaller idle is needed, idle is less dependant now. This was a major breakthrough and taught me not to go on what the old one wanted.

I must admit to being completely lost yesterday.

Maybe the carbs have different sized progression holes? I can't be sure.

This cleaned up the fluffing and lumpness and plugs became sootless on the edges as a result the spark is cleaner and more constant, the engine came alive.

I stayed on the 150 corrector as after testing 170 is was evident that it went lean and overlap was poor, plugs bit white and hot to the hand. The engine started to run much stronger at this point when going back to 150, I then felt confident to make some short WOT power runs and advance the ignition up to the max, to the point of mild momentary knock then back 1.5degrees...there goes long run in period, doesn't need it, its ready for action and loosened right up!

Here was a major breakthrough, the engine runs like terribly and misses and runs rough with no power without the advance being up at 13-13.5 BDTC static and the right jet feels awful- 11 deg dissy weights- 35-35.5 total, back it off to 10-11BTDC 32-33 total its awful in the lower end and mid range.

The engine is much more advance sensitive than the last one for some reason, not enough its awful...I hadnt been running enough advance the last two days due to concerns with the rough running, which turned out to be fuelling rather than timing regardless of float issue.

After a few more 1st and 2nd gear WOT runs to 6000rpm I was confident enough in the timing to make some conclusions from various signs that it was right and proceeded to add more fuel as I was confident it would take it...On the retarded ignition the other night 120 was over rich but now it can handle it fine.

On the 112 there was not good power WOT and at cruise- the engine wasn't "leading" itself but needing throttle to drive it at cruise. My old engine drove itself and punched you when you decked the throttle, thats been missing completely till now.

So out with the 115mains and there was immediate increase in power and cruise was good but still a little retarded, the engine made a familar grunting/gurgle noise during a short WOT run in 1st and 2nd, lean, plugs told me the same story, lean.

So I switched 120main the noise was gone and suddenly a huge ammount of power was found!!!!

The cruise and low TP performance came into the zone I remember and when you deck the throttle there was a big increase WOT power in higher gears and the engine leads itself alone nicely in the low TP cruise, effortless no pedal use really to follow traffic...On the old engine for road work the only time you used to open it up was when you wanted to arrive at the next corner fast or overtake, that feeling came back, big torque feeling at low TP...Effortless cruising.

I think possible it could take a bigger jet still maybe 125. This is cause of the compression it needs more fuel, according to Josh B, and he's right...Also cause the idle is so small the engine is using the mains over a bigger rpm range, so when I have full control over it, it should be highly active and punch like tyson. The extra CR ratio shoudl give me the powerback that is lost from the FR89 cam and more torque etc.

Its not perfect yet I am not gonna get carried away, there's work to do, but I have found a solid base now - 90% as good as the old one and its got some good poke that production car quality is coming to me! Mechanically ts super smooth in the WOT delivery in lower gears and pins you in the seat, thats without even using 7000rpm +, the old one was just really getting into the big numbers at 6K, so its all good!.

I had it on some big oversteer in 2nd a few times exiting corners and it just span up the rear tyres thats without commited entry just booting it out...Good signs!

The pumps will be hardly needed like the old engine as the mains are super active and on early - I think they are giving too much fuel over too much time atm, I will perfect the general pickup and power first then go to 35pumps from 33 for less duration and reduce the delivery quanity till it dives a bit then go back up...Games for another day.

Noted the fuel economy was crap before, its coming back now...Old motor was 35+mpg on a motorway...10-15MPG at full charge 8-)

I'm a happy bunny its delivering goods and found WADS of power today- I have solid and working jet base which is very different to the old one...this is pleasing.

Took me 5hrs today, I think did atleast 30 stops, timing and jet tests and burnt £25 of super! If you left the rolling road, you'd probably be happy with it, I am, but I am a perfectionist and there's still much work to do. I aim for levels of clairty on the Dell'ortos that others don't even know exist, no comphremises -as good as fuel injection.

It still hasn't used a drop of oil on the dipstick in 350miles or so, and that was running in!!! meant to use a bit arent they! by now the old engine would have used/dumped 1/3rd of a pint!!! there is no splatters or back mess on the rear valance , the old motor added most of its oil onto the back!

Its becoming a joy!

Once I get it completely sorted I will go and see how much power its got on the rolling road and add the 1.75 roller rockers and set up the jetting with a sun machine, as its all high end its dangerous and I don't want cause the engine any harm, so I'll resort to using a machine and electronics not my eyes, ears and hands, software dyno says 10-11HP over 6000rpm peaking at 7500 on those, but we will see!...

My whole aim was use the TH5 for torque and extend its powerband and potentcy with the rockers...We will see...The Fast Road 89 from the last engine should give 5 BHP more than the TH5 on equal CR - only over 6000 but less torque and mid range, by about 5hp-5lbs of torque...So I hope for the best of both worlds...When I added the roller rockers to the stock 1300 big crank (18-58 cam lol) it gave more power in the middle I think, so I might find a raise here too? There's hope...

Diff needs daily oil filling? so I will drop the backend off soon, the pass side output flange seal has gone...the diff is a rattler anyway.

I think I will defintely switch to synthetic oil shortly after another 200miles, also the oil is VERY clean still, I'll cut the filter open tomorrow and have looky inside, change it for a new one. Oil pressure figures haven't really changed at all. The engine is very much looser now.

Re-torqued the head to 60lbs tonight and checked the the tappet gaps were all still even, good to see if anything has gone bad etc. With new tappets, pushrods and rocker arms you NEED to redo the tappets alteast 2times at 30minutes running time and 250miles odd - as they run in and the gap will change on various cylinders by 1-2-3 thou or so ....If there's any big variation like 10thou you have cam and follower troubles, best adjust your start up proceedure!

HAPPY BUNNY!! Got to bed at 4am yesterday and up and 8.30am its now 2.30am....bit shagged!

No comments: