The SRs are being hit hard by the Edelbrock RPMS. Indy has lost a lot of sales to them. I have a set of SRs from the late 90s that are untouched. They compromised the head even more because with the raised port setup, it didnt work with any headers, and it was a bear to get into A body chassis. RPMs knew what they had to be after the SR's release...lol. They are a smaller port volume. I like that. In terms of similar, the SRs use the exact same castings as the -1s, but the port openings and pushrod holes are different. Which led to the -1s and the offset rockers. The EZ exhaust port leaves some room for improvement, but does fit the cars. The SRs dont, and need TTI headers to work right. Flow wise, the SRs will not flow near the -1s, because the -1s are always max wedge sized opening. SRs could be gotten in std port or MW, but even in MW form, the pushrods were located in the stock spot. So the MW SR cant move the same flow. Not even close in fully ported form. Indy is famous for overstating and/or skewing flow numbers too. It wouldnt surprise me to see the SRs be cut and dropped. Especially with the other options that may be around in the future.
