R5335

Thanks all for your quick responses. Greatly appreciated

Thanks for that quick response. Do you know how much the R3 was shimmed up? If I recall correctly, the Avanti II's was raised about 3" for the corvette engines.

So an interesting topic and Dwight mentioned early in this discussion that caught my attention. His comment was that the R3 body was slightly elevated vs the R2/R1. This is the first I've heard this. I've read that when the Avanti II's came out with the corvette engines, the body was raised a few inches. So how much was the R3 raised above the R2/R1? I'm somewhat new to the Avanti ownership, and purchased a 64 Avanti in the spring. It had been modified extensively from an R1 originally to an "R2" but the air box is not an R2 hat but an R3 type box. With that, I've noticed that it "just" touches the underside of the hood and I've been trying to decide how to fix. The 3 options seem to be, a) change the engine mounts to something a little lower, b) add shims to raise the body like an R3 (if that is what they did) or c) replace the R3 type airbag with an R2 hat. Looking forward to the feedback

Once again, thank you for those quick responses. Glad to clear that up.

Question regarding heads for Avanti's or any Studebaker. I've reviewed the info on Head castings from Bob Johnstone's website and what I gather is the key difference in head castings for R1 (1557570) vs an R2 (1557582) vs lets say Golden Hawk (535976) or (1555294) appear to be the combustion chamber volume. Somewhere in the review was the comment that valve sizes were all the same regardless of head casting, with Intakes at 1" 17/32 and Exhaust 1" 21/32. My question is this. Is there any difference in intake & exhaust runner sizes/volumes? Are they all the same? Is it then true the only difference is combustion chamber volume? Are there any differences other than combustion chamber volume?

Thanks for the photos. Helps a lot for understanding the issue

Do you have a photo of the mating plate between the bell housing to block? Thanks

So, I was researching camshafts trying to understand what I've got and why and was wondering why the R1 and the R2 used the exact same camshaft? Watching a variety of "Youtube" videos, it seems as though the R2 might have had better performance with a different camshaft designed for positive pressure intake, ie "blower". What's the thoughts out there amongst the experts? Have any updated their camshafts for the R2 setup to improve performance?

Thank you mfg. I've been on the road so I hadn't had a chance to respond. Good info though and I was thinking about those engine mounts as a fix

Thank you for that quick reply. So to add to this question or next question. Is there a difference between a R2 intake manifold vs a R3 intake manifold? What I've noticed is that with the R3 air box, the air box is slightly rubbing up against the bottom of the hood. The insulation on the underside of the hood has already been removed, I presume because it wouldn't close with this air box. Even still, there is a slight rub.

Is there a difference between a R2 supercharger vs an R3 supercharger as far as performance? The obvious is the air box on top of the carburetor so because of that, I was curious if therefore there is a difference between them. Also, where on the supercharge can I find the model number/part number? Only thing I've found is "MS 2380". The air box on my car looks like an R3 and has a casting #/part # on the top of 1558946. My car that I just purchased has been modified over the years. The block number is a standard 289 cu inch with the casting # of 1554641. The heads are from a "golden hawk" with a casting number of 535976. The intake manifold has a casting # of 1557144. I'm still going over the engine and transmission looking for casting #'s/part #'s. The transmission has been replaced with a chevy 700 4R.