No 18/13/12 degree SBC heads with stud-mount rockers: why?

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NewbVetteGuy
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No 18/13/12 degree SBC heads with stud-mount rockers: why?

Post by NewbVetteGuy » Mon Nov 13, 2017 1:40 pm

This is probably a dumb question with a really obvious answer, but, why aren't there any 18/15/13/12 degree SBC heads designed for the Street /Strip market with things like stud-mounted rockers and appropriate-for-the-street combustion chamber sizes?


Most of the tech from LS engines is available to the SBC platform street market today, with the exception of the better valve angles, which seem to be one of the most important features in terms of making gobs of power and torque; why?

We've got folks like Profiler who have 13 Deg SBC heads that can flow 400 CFM for less than a set of AFR 23 Deg heads, but then you have to get into really high static CRs because of the small chambers, and high-rpm capable shaft mount rocker setups, and $$$$ headers (which would be cheap if these things were more prevalent).

Why are there no street-focused SBC heads with modern valve angles? (I know there's people like Chad Speier still getting awesome flow with 23 degree heads, but this still seems like a no brainer; these really great 23 deg heads are all focusing on the maximum flow in the least CSA to maintain great velocity and the modern valve angles just do it all day long easier and with more CFM still, right?)



Adam

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Re: No 18/13/12 degree SBC heads with stud-mount rockers: why?

Post by Zmechanic » Mon Nov 13, 2017 4:00 pm

Target market. Target market is higher performance, and in that market it's usually a given to use shaft mounts due to vast improvements they offer.

Also, SB2 heads can make killer street motors.

Frankshaft
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Re: No 18/13/12 degree SBC heads with stud-mount rockers: why?

Post by Frankshaft » Mon Nov 13, 2017 4:27 pm

Mainly because of the severe offsets required. And the stability, for the higher rpm those heads allow

Brodix does offer an 18 degree head that uses stud mount rockers. It limits the full potential of the head.

tt 383
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Re: No 18/13/12 degree SBC heads with stud-mount rockers: why?

Post by tt 383 » Mon Nov 13, 2017 4:36 pm

Define street focused...

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