TURBO!CB Competition Eliminators 48/40. Dyno and bent pushrod.

[JLH]

I have talked a bit to CB/Mike Lawless (E-mail) asking about their Race Master Valve Springs if they fit and what type of pressure they are rated to, and also what type of pushrods they recommended. This because almost everything used in head/valve train is CB products except from cam and lifters. He recommended to stay with the K800's (gave him all my engine specs) and use the dual taper cromoly push rods:

 Take a look at the #1629 Dual taper push rods. These are a lot stronger than the ones you were running and will hold up to the k-800 valve springs.

http://www.cbperformance.com/product-p/1629.htm

 The K-800 is what I would recommend for your engine.



So......Heads are going off anyway to make more clearance. Good the winter is long so I can get things sorted one and all.  

A spring change and dual taper alu pushrods are in mind  

[SSRT]

"ignition as low as 8.3 BTDC for a very short moment"


This might be the problem...

[Erlend / bug66]

Go with v8 springs. All the springs in the world to choose from.

I’ll check the name on mine. They are perfect for your engine

[Martin S.]

Apparently the BMW guys like to use our air-cooled VW springs  

[Martin S.]

"ignition as low as 8.3 BTDC for a very short moment"


This might be the problem...

This is a good point. Can you post your data logs of the run just before the bent pushrod?

[JLH]

Short update after a long pause from the garage. Engine is still OK and gives no sign of damage other then a bent pushrod. Engine turns smooth and runs great. Even in this cold Winter weather 3-4C. Now time to take it out to machine the heads for more pushrod to pushrod tube clearance   

[JLH]

Update.

The heads got some machine work on them and we ended up moving the holes for the tubes to seat in, by making a new chamfer for the PR gasket off center from the original center of the hole. That's the short way to tell the story, but was some hours making it happen.
But now i have no rubbing at all!!! Running tapered alu pushrods on K800 springs.
Have done some low boost tuning and ended up with 307whp, 424nm at 7400rpm max (for now) WITH 14,5 PSI and pump gas.
Can't wait to get some E85 in there and more boost.