Mythbuster: continuing project thread of my 1303 '75

[Wally]

Flange machined flat again after it warped after welding and the neat oil return flange:

[MX67]

Speaking of oil feed tube...

Wally, sorry if you've put that info somewhere, but which oil do you use in your engine?

I'm asking because there's much debate going on about zinc levels in modern oils. I'm reading some ricer forums and they're speaking about Brad Penn grade 1 20w50 as the best choice. Jake Raby also prefers that oil. Maybe we should make "oil thread" on GL...

[Wally]

Originally Posted by MX67

Speaking of oil feed tube...

Wally, sorry if you've put that info somewhere, but which oil do you use in your engine?

I'm asking because there's much debate going on about zinc levels in modern oils. I'm reading some ricer forums and they're speaking about Brad Penn grade 1 20w50 as the best choice. Jake Raby also prefers that oil. Maybe we should make "oil thread" on GL...

I fully agree on the Brad Penn 20W50 as I also run the GT1 'racing green' in the engine. Its still called Kendall here though

But please not another oil thread... enough of those already.

[Xellex]

excuse me if I got it wrong, but is the waste-gate gonna have it's own silencer to the left, and the main silencer is going in the old position? Couldnt the WG dump in the same exhaust pipe?

[Wally]

Originally Posted by Xellex

excuse me if I got it wrong, but is the waste-gate gonna have it's own silencer to the left, and the main silencer is going in the old position?

Yep, each its own silencer.

Couldnt the WG dump in the same exhaust pipe?

Yes, could, but (most important in my case) that would probably be too loud as the exhaust silencer will be 3,5" and the wastegate doesn't have the turbo as a "pre-silencer". Most tracks get really difficult with noise levels...
Its also better to keep it seperate for the least possible backpressure in the downpipe.
Lastly, there was probaby going to be possible ground clearence problems routing it back into the downpipe exhaust.

[Wally]

First start up after too long a time:

http://www.youtube.com/watch?v=_wk-2XcIbx0

[Bad bug]

Oh! hell the beast is back. More vids wally. Ah! just a question, how much horsepower do you intend to make this time?

[Wally]

Tnx guys! Just a new lambda bung and the big turbo silencer and I can drive again

Originally Posted by Bad bug

Ah! just a question, how much horsepower do you intend to make this time?

No intentions really. I hope the same or a little more at less boost. No telling really. I am more interested in how much further boost threshold will be. Or my own benchmark: at what rpm 15 psi will be reached. All logic says about 1000 rpm further on. Anything less will be a bonus and/or to be adressed to the TS

Interesting will also be how the heavier CB 650 valvesprings will go along with my stock 'non-straight-cut' cam gear and stock single thrust cam bearing...

[70Turbobug]

Nice job Wally! I´m anxiuos to see what it does on the track and dyno!

[wrenchnride247]

Very nice Wally!

[judgie]

looking/sounding good

[NO_H2O]

Good to se that she has a pulse once again. Nice work.

[70Turbobug]

Indeed interesting info! I wouldn´t have thought that the loss in pressure would be so dramatic! One possible explanation would be that the advertised spring pressure exceeds the the tensile modulus (http://en.wikipedia.org/wiki/E-modulus) of the material used.To put it simple the spring pressure is calculated in such that the steel returns to its original strength after "stretching" without loss of tension.This value is the same no matter what steel is used,whether its a cheap steel or a high tensile alloy just as the expansion rate is the same if they are of the same diameter.The diameter of the steel is the key and base for calculation - not the alloy!! If the force applied exceeds that value (calculated in mm²),the material will wear quickly.Hence,the advertised spring value is higher than what actually should have been calculated.

[Bad bug]

Have any of you thought about using oteva 75 springs from Sweden. I don't know about the price but from what i hear they are good.

[Wally]

Originally Posted by Bad bug

Have any of you thought about using oteva 75 springs from Sweden. I don't know about the price but from what i hear they are good.

Yes, I looked and i believe they are probably very good also and could be much set-up like the CB's, however they are also 3,5 times the cost of the CB's (which makes them 10 times as expensive as a 'normal' spring set...).
I'll try these first

Got the 3,5" bore Borla XR1 silencer in today!