The '2 ton bugswatter' - back for a gentle stroke

[Billman]

Very nice results JP. What is the inducer on this new compressor wheel? What are the steel bearings race? Ball bearing?

[JP]

Very nice results JP. What is the inducer on this new compressor wheel? What are the steel bearings race? Ball bearing?

Thankyou

No idea what the exact wheel spec is on the wheels. I phoned owen developments up told them what I was doing and what I wanted and they put something together for me using my k26 hotside.

As for the bearings they are ball bearings as normal. However the cages that hold the little ballbearings on a stock bearing are made from some sort of nylon polymer which melts under extreme conditions which is why the bearings fail. So they replace the nylon cage with a metal one which lasts longer as it doesn't get effected by heat the same way.

hth

[europeanme]

the power loss on run number 2 is more than my wifes car has got in total..

sweet results JP, I bet your chuffed to get those kind of results....

[Jamo]

As for driveability in first gear I've got to catch it to stop it bouncing of the limiter at 8000rpm as once the turbo comes alive at 4k it rips round. 2nd it still tearing it's *** of and by the time we get to third well I haven't found anywhere that I would consider safe to try it's strictly track day only in the upper gears till redline.

The intake manifold can do with being a bit better now there is a tiny bit of surge in the higher gears as it starts to come onto boost just before 4k if pulling from 2k it's there for just around 50-100rpm which can be resolved by downshifting (eventually a better intake though).

Really happy with how it's turned out it's coming on power the same as it did with the smaller 3076 with a 0.63 housing on the 2.2 @ 2.1bar and carries on to make more power for longer running 1.75 bar dropping to 1.65bar, I did force it to hold 1.75 till the 8000rpm redline at one point but the exhaust/wastegate became such a restriction it lost 20hp so I got the controller to trim it at 7000 and 7500rpm.

Ah so the 3" system is a restriction? and your running less boost? I was wondering as the overall torque figure is lower than your 500+ run with 700nm torque way earlier in the thread but if your running .035 bar less with only a 40nm drop off,with a better exhaust you should surpase that easily.

[A80Avant]

is it an illusion or does the turbine impeller seem slightly smaller on the new turbo?

probably an illusion.

Really nice results. Amazing what you can do with a properly done stroker!

[Jonnybravo]

Do you use solid lifters in this Jp ? What valve springs ?

Sorry if it's already been answered

[JP]

is it an illusion or does the turbine impeller seem slightly smaller on the new turbo?

probably an illusion.

Really nice results. Amazing what you can do with a properly done stroker!

Just an illusion they were identical as I re used the hotside of the old one which I send to Owens to match up and thank you.

Jamo the 3" system is not the restriction but the stock backbox at the end of it .

Torque wise yes more boost would yield more torque but I wanted reliable driveability on this setup so kept the boost lower with egt's measured at the exhaust port staying below 900. (Approx equivalent to below 800 after the turbo).

I also reclocked the cams so it had useable power over a broader powerband rather than peak figures as I found on the old setup on the strip it'd drop out the powerband on 1st to 2nd gearchange costing valuable time.

[JP]

Do you use solid lifters in this Jp ? What valve springs ?

Sorry if it's already been answered

Supertech springs, valves and retainers. Stock late aftermarket ina hydraulic lifters which appear to be identical to the lightweight ones everyone sells in the US.

[Jonnybravo]

Cheers Jp.

Do you experience much problems from high rpm use on hydraulics ? Seems you have avoided the need to rev it high constantly which isn't a bad thing, seems to be a problem I know people are having on other engines.

Hope it cracks the 11 sec barrier, either way it's going to upset a lot of people if anyone tries their luck against it on the road !

[Thuppu]

Nice result! Compared to the old one this should really hold you in the seat to the limiter.

Did you do any mods to the oilpump? You dare to rev to 8k..?

[JP]

As the car stands on the road I'm finding myself short shifting at 6500-6800 it actually feels strange carrying on to 7.8k although feels faster when I do. Stock lifters I tend to say 7500 continuous with 8k peak on 16v lumps so as they're the same I'm sticking to the same rule.

Oilpump wise they start to cavitate above 8k a problem that's made worse by running too thick an oil. I use 5w40 fully synth from Audi the platinum stuff. As volume of flow is more important than pressure at high rpm, running a temperature suitable oil with less top end pressure is the way to go as it is less susceptible to cavitation and will help pull the heat away from moving parts much better than a 10w50 for example.

[A80Avant]

do you get the 5W40 oil burnt easier though?

Catalysts still in place?

less than 900C with 0.80 lamda at the top end is really hard to keep with smaller hotsides. Obviously the 0.82 K26 is bigger than any 0.63 garrett equivalent, so it makes sense that way.

[JP]

Never noticed oil consumption of any significance with 5w40. Only oil loss I ever see is what collects in the catchtank.

[Sleeper_Avant]

JP, you still using blow through MAF?

Sean

[JP]

Yep maf on the pressure side with straps to stop hoses blowing of.