It's a 2 barrel engine. All I really want is the blower setup. I don't want the "box" type setup and hopefully I can change it over to the "bonnet" style? I plan on using a small cfm Holley 4 barrel when I get it all together. The McCulloch is a variable ratio blower and in many ways is a better set-up since it 'loafs' in low blower until you floor it. You are going to have to do a lot of modifications to use it with a 4 barrel on a early engine though.. I am going to put the '58 blower on the '63 four barrel engine. I wasn't sure whether I'd need a sealed Holley carb or something like that. I swear that I saw a setup exactly like I am trying to do somewhere out there in internet land. To re-cap.... I am putting a '63 4 barrel Hawk engine together. Bored .060 over, head work, cam, Holley carb, electronic ignition, big exhaust, comp ratio around 9.5:1, etc. I have a '63 Lark V8 auto to put on the Hawk engine and a blower setup from a '58 Packard Hawk. I intend to put the '58 blower setup on the '63 engine. I am sure that I have enough hood room for the top/front mounted blower setup. I don't want to use the "box" but the "bonnet" setup instead. I am thinking that I just have to get the carb bonnet (Avanti style) and the hose to connect the bonnet to the blower. All of the '58 blower setup components excluding the intake should snap right on the '63 engine, correct? Sounds like the McCulloch from the '58 is the better choice of superchargers! I was just lucky for once. First, the top mounted early blower will not clear the hood if it's going in a C-K , second the Avanti bonnet will not work, but the Lark R2 bonnet could be adapted, third, the supercharger mount will not work on the late V8 water manifold, worth with 9.5 to 1 compression you'll need racing gas only since your effective compression ration under boast will be over 12 to 1. Hate to pee on your parade, but you'll be in for some work. You can use the early water manifold, just need to do some plumbing. BTW, if Ted says you can run 9.5 to 1, than I stand corrected I just have a problem with not being able to run full advance with the stock R2 compression on what passes as gasoline today. The R2 Lark bonnet has been repro'ed. I would tend to conclude that if a variable speed blower is going to be used, you would want to start out with no more than 8.5:1 compression.... I have done this exact thing to a McCulloch to use it R2 style... it's really very easy. There are only 2 mods needed.... remove the rear scroll housing, and rotate it about 120 degrees. When you bolt it back together, 3 bolts no longer line up with the recesses in the bracket for the boltheads.... so............ you have to countersink the housing and use tapered head machine screws instead. The only other thing needing done is to use "heat dissipation shielding" (aluminum plate, gasket, plate, gasket...etc) to raise the carburetor to line the Bonnet up with the outlet of the blower housing. studeman That's assuming you are using the late R2 mount, not the early one. -------------- Let's just make this as simple as we can... You have an early GH unit correct?.. and your intent is to put it in a '50/51 Bulletnose.... Then, You must use....... A. the water manifold, B. blower mount w/tension arm C. lower crank pullys (I used the whole unit including hub, balancer, etc) D. McCulloch Supercharger- you must "roll" the scroll housing E. Get a repro HAWK R2 BONNET (bends to the left- NOT straight) F. Use an R2 OR GH Fuel Pump. G. Plan on fabricating a K&N Air filter setup -I don't know about the interface of the Holley and the R2 Bonnet. -I don't know if you can easily pressure seal the Holley. -Forget about trying an R3 Box... You simply cannot use it with the GH mount. It does fit, but you have no way of fitting an air intake to the back of the blower. Unless you want to shove unfiltered air into your engine.... -You do not have to use the (ugly) GH oil fill stem (I made a polished aluminum plate to cover mine)...provided your Valve Covers have the stems for the oil fill caps. -You may have to use "thinner" motor mounts to lower the engine - I used '57 Chevy. -You may have to "raise" the body/fenders/hood by using shims at the body mounts for more clearance. Note: My engine is running (calculated) 8.75:1 (unblown) compression, The McCulloch Blower is fitted with an Erb High-Output impeller, He also tweaked the valving to change the "shift points", and I can use 87 Octane for be-bopping around town....If I give it a workout... I run premium (93) with no pinging at all. I run 8 deg BTC at an idle (750 rpm- no vac advance hooked up), and a stock 1110864 distributor. Studeman ------ I don't recall this but I would say with 9.5 and supercharged, you should expect to mix some racing fuel with 93 octane when using the blower at high boost (about 5 pounds). It would depend some on the head, how much the chamber has been cleaned up, etc. but I wouldn't want to go over 9.0 and then would want at least the 93 octane with 5 pounds boost, at least for any extended period of time. The R 2 was 9.0 and gas was a lot better 40 years ago. I would think you could run close to 10.0 with 93 octane. Trouble is, 93 is not available in many areas. I just heard from a fellow in La Mesa, California and said they are down to 91now. Around here, I can run 8.5 without any trouble on 87 octane in both my Cruiser and truck and the truck is actually a little more than 8.5.. Ted --------- Found my Paxton R3 spec sheet. The pistons were Alloy: 2018T6 tin plated Weight: R3: 16.64 oz., R4: 19.82 oz. Clearance: .009" below oil ring and the pins Offset 1/16" towards thrust side, Length 3 1/16 Dia .875 Weight 5.44 oz. Clearance in piston .0005 to .0007" The real question is what was the shape of the skirts? Cylinder wall clearance defined at a lesser piston width at the oil ring is not too meaningful. The real question was what was the clearance at the max piston skirt width. My guess is that this max width was perhaps .003" more than that just below the oil ring. This would result in a .006" clearance that could be measured with a feeler gage. I'm measuring .010 where I would expect this .006"