Here is a link to SSBC's "firm feel" master cylinder:
https://www.summitracing.com/parts/TSB-A0463
It's over $300 and comes as part of the $1k+ kit if you get their rear disc brake conversion. It
appears, at least on the outside to just be a 99-06 NBS master cylinder with an adapter screwed in on one side.
I believe the same as you regarding SSBC's MC. Little Shop Mfg's MC is similar / identical AFAIK.
FYI, the NBS MC is appropriate if one's doing a rear disc conversion, as the reservoir is large to accommodate the volume of fluid required. But I and others have used it for a disc/drum setup.
Having said that, the 8600# MC (OE for disk/drum) is just as appropriate for your setup, perhaps more-so because it's piston diameter is smaller than the NBS MC's... which means more braking effect for a given amount of effort.
@Schurkey has made this point many times.
Is there an issue with using the smaller, "quick-take-up" front calibers (JB5) with an NBS master cylinder?
@Schurkey has commented on this topic often. The issue appears to be the lost motion required of the smaller, non-quick-take-up MC piston that's necessary to provide the gush of fluid required to bring the quick-take-up calipers into play. I'll try to explain. The NBS and 8600# MCs do not have the large, quick-take-up specific piston which is designed to come into play upon initial application and provide that initial gush to the calipers to "quickly take up" the slack space (which, by my thinking anyway, is one of the reasons for the crappy feel of those the quick-take-up brakes upon application, esp. upon
panic application).
The attached document will aid in understanding, it's a simple 2-pager from Bendix / Allied Signal which explains the quick-take-up brakes and the mixing / matching of components.
Of course, there's anyways the question of "Do you
really have quick-take-up calipers on your truck?" (as noted in the Bendix document), and if so "Are they working as intended?", which may not be the case. So these are reasons why I simply $h!tcanned the JB6 front brakes on my Suburban and installed components (NBS / JB7) which were non-"quick take up" by design.
This truck is meant to serve as a light duty, inexpensive shop truck. I'm not planning on racing, hot-roding or even towing with this truck. It doesn't need heavy duty brakes for any reason.
Acknowledged.
Honestly, Dad's 1995 K1500 RCLB w/ JB5 would brake reasonably well, it was certainly a better "feel" than my 1998 K1500 Suburban w/ OE JB6 brakes... and I'm sure that his rear drums were never given a "drums-off adjustment" the entire 10+ years he owned it, and the brakes were probably never bled. Dad's truck was a "driver", rarely carried much of a load or towed much of a trailer, akin to yours.
For the record, my 1998 Suburban was a different beast, the OE JB6 brakes always left one with an uneasy feeling during initial application, and were downright scary in a panic. So I took every step I could muster (except hydroboost, tho I have the parts) to improve the brakes and, I believe, I had great success... I'm very happy, anyway. I made my changes more or less step-by-step literally over the span of years, and with every step the braking was improved... sometimes the brake "feel", other times the braking "ability".
Both trucks had the quick-take-up brakes. Why the difference? I'm not absolutely certain. The Suburban weighs ~6300#, Dad's RCLB was certainly less.
All I'm trying to achieve is a nice safe feeling when I brake instead of the long travel, spongey feel of uncertainness I have now.
Understood.
Let's see what others say, and I'll mull it over as well.
@Schurkey has already weighed-in, and may comment further. He knows brakes.
