New L31 - HT383 Cam - COMP Cams 1418-16 Roller Rockers - Rubbing

[m002922]

Interesting. Seems some have rubbing, some don't. If I have to pull the heads off to machine to have 1.6s that is not going to happen on this motor.

I'll ask the stupid question because it seems like I'm missing a lot of obvious stuff. Are .1 longer pushrods required with 1.6s? Summit tech says so - that's the first time I've seen/heard that . . . didn't see anyone else talking about it, and didn't see it in Comp Cams instructions . . . but maybe it's just assumed you know that.

And I see your point about the Scorpions now that I look at the two compared. I don't think I can send my others back, as they've been on the motor, so I'll have to figure out another use for them.

Additionally, anyone else not getting emails when they've subscribed to a thread? I missed the last two emails on this one.

 

[Supercharged111]

The answer to the pushrods is that it depends on the rocker geometry. To say that all 1.6 rockers require a longer pushrod is not necessarily a factual statement.

 

[GMTMark]

If you are within their return window of time, return them and buy Scorpions or stick with 1.5. the 1.6 doesn't give much performance increase in street applications IMO.

 

[Supercharged111]

If you are within their return window of time, return them and buy Scorpions or stick with 1.5. the 1.6 doesn't give much performance increase in street applications IMO.

Either ratio will require checking for correct pushrod length because in both instances you've deviated from stock.

 

[PlayingWithTBI]

Get one of these -

https://www.summitracing.com/parts/tfs-9001

 

[slowburb]

Super is right. Pushrod length checker is the proper tool. I checked with my setup before installing the Scorpion 1.6's. I wanted the Crane Golds that are OEM on the corvette sbc but they were on indefinite backorder or something so the Scorpions were substituted. Quite happy with them I might add. No interference with holes in the heads and no interference with the valve covers.

 

[Supercharged111]

Super is right. Pushrod length checker is the proper tool. I checked with my setup before installing the Scorpion 1.6's. I wanted the Crane Golds that are OEM on the corvette sbc but they were on indefinite backorder or something so the Scorpions were substituted. Quite happy with them I might add. No interference with holes in the heads and no interference with the valve covers.

Last I checked GMPP made aluminum 1.6s and I want to say Crane makes them?

 

[slowburb]

Last I checked GMPP made aluminum 1.6s and I want to say Crane makes them?

Yes, they're the crane gold rocker arms.

 

[Supercharged111]

I thought so, they're just not gold anymore.

 

[L31MaxExpress]

I thought so, they're just not gold anymore.

As far as I know they never have been Gold from GM. My set from back in 2006 were silver with a Bowtie stamped in each.