ECOTEC - Are High Lift Rockers worth it ........

[galahs]

I have heard someone mention split ratio Yella Terra rockers.

I'm guessing this means using higher lift rockers on the intake and slightly less lift on the exhaust.

Where can I find more information on this?


And is there any information available on the net on Yella Terra's latest ultralight rockers?



We all know FITs products produces the goods, but I would be interested to see how Yella Terra's latest release compares.

 

[holden#1]

all you revheads - just wondering what fitting aftermarket rockers does to your fuel economy when you are driving in places other than the drag strip?

 

[Raptorsc]

holden#1

all you revheads - just wondering what fitting aftermarket rockers does to your fuel economy when you are driving in places other than the drag strip?

To answer your question on fuel economy, the current cruise fuel ecomony is:

Is currently between 8.5 and 9.4 L/100km @ constant 100kmh

Before rockers it was 8.5 and 9.1 L/100 @ constant 100kmh

 

[sircruisealotVS]

when i fitted my rockers i was actually getting better fuel economy than previously, but then its all relitive to how you drive.

 

[holden#1]

when i fitted my rockers i was actually getting better fuel economy than previously, but then its all relitive to how you drive.

I suppose just because the extra power is there - you don't have to use it all the time!

 

[Immortality]

i don't really see that roller rockers should change the fuel economy because the difference isn't really noticed in the output of the engine untill it gets up in the revs and how many of us drive that aggresivly day to day. the split ratio rockers are sometimes used to increase the exhaust to intake ratio so the bigger ratio rocker is normally used on the exhaust.

 

[Jesterarts]

I'm assuming that with the 1.95:1 ratio rockers the gains in power would be similar to that of the 1.97:1 ratio rockers right??

 

[Immortality]

I'm assuming that with the 1.95:1 ratio rockers the gains in power would be similar to that of the 1.97:1 ratio rockers right??

more or less but with the YT product you gain all the benefits of roller rockers where the FIT one's are just remanufactured holden rockers. roller rockers reduce valve train friction, the roller tip doesn't put a sideload on the valve stem so your valve guides won't wear out as quick and they rev really well. a better product all around and cheaper too. can't see a point in getting more expensive product thats actually used already

 

[Jesterarts]

Oh yeah, even if i make a touch less power with the yella terra ones im still gettin em! lol
Brand new high quality roller rocker vs. a dunno how many KM remake...lol

 

[aokman]

Yup higher lift rockers are the way to go, the split ratios have a higher lift in the exhaust to help balance out the flow and get rid of the exhaust gases.

ANY power figures you read on FIT vs YT rockers is just bull, they have never been directly compared. That said i would expect more gain from the split ratios due to them being lighter, having a roller tip and optimized for forced induction. The smoothness from the roller tips will keep the power smooth and it really make the ticking at idle from mine much quieter.

Remember just because YT haven't said that their rockers do not require a valve spring upgrade, doesn't mean they will, they are just covering all bases. Many people are running 1.95/1.9 including me on stock springs with no issues, i have 130,000k on the clock.

Anyone who say that YT rockers definitely do need a spring change at the stock rev limiter are just speculating. In fact they are lighter than normal rockers so there is less chance of valve float.