So,....on the head issue, nuthin wrong with a Hemi, right? I coulda been stubborn (the wife reminds) and held out for another set of Poly heads. However, instead of buying more iron, why not use some of what I have. Today I started on the port matching. Kinda satisfying job. After that the heads will go to a local Hemi Head hero for modest port cleanup and valves, springs, etc. Also while waiting for the machine shop, I decided to start on the timing cover modification. Although you can buy one from Hot Hemi Heads that accommodates the SBC waterpump, that's more $ and modifying the stocker is another satisfying project. I'll have the seam TIG welded by a friend who has a better "hand" than I.
Totally impressed with your thread and insight. Can't wait, I bought an older engine from the 80's mainly for the Magnacharger on it but will pull it down to check things out before using it
Love those carburetors. What are they? I'm planning for something like that for my blower setup. This is an old pic from some years ago. My project has evolved into incorporating an intercooler and now a Hemi of the same displacement. Fortunately all that was planned for the Poly still applies to the Hemi.
Delortto’s 44 mm. Used on lots of foreign cars. Lots of the downdrafts on VW’s. Good luck on your hemi
So,....got the timing cover back. Thinking I may lave the weld bead unfinished. Also unearthed a killer steel billet cam along with a couple stockers. That I'll never use. If anyone is interested, check https://www.jalopyjournal.com/forum/threads/hemi-baby-hemi-cams.1196037/ And while waiting for the machine shop to call, busy hands started on the headers. So far it's just flaring the 1-1/2 primary tubes to fit in the 1-5/8 flanges. After tacking they'll probably be on the shelf for awhile.
Been almost two weeks of cogitating on this project while waiting on the machine shop. So,.....I'm adding this little sidebar, subject a bit outta sequence and I'm needing some help. My original thought, some years ago, was to put a big honkin Weber carb on that blower inlet. How cool would this look? I've spent some time stumbling around the inter-web, tryin to get smart on side draft carbs and/or side draft EFI. Side draft is a requirement. So far I haven't found the guy or the company that can talk to me about this idea. I'm looking for a 500/550 CFM capability in a draw thru side draft carburetor or TBI. So far all the published specs I've been able to find come up short. However,....those specs apply to naturally aspirated systems. I understand that some tweaks to fuel and ignition will be required but, can I expect a greater CFM on a given carb or FI system if the blower is helping air flow. I'm hoping someone watching this thread can offer observations or comment or recommendations or links that can help get me unstuck.
If space is an issue then Dellortos are slightly smaller than Webers, have no info re any comparission between them as far as tuneability is concerned.......here in Oz the V8 Supercars( sort of like our version of Nascar) for a while used a pair of DCOE or sidedraft Webers mounted to a 90 degree adaptor type manifold that bolted onto a single 4 intake manifold, each Weber was on opposite sides of the engine, similar to the twin magnuson engine shown .........these adaptors should still be available.......... dunno if this helps..........the reason for the twin webers was that they offered supposedly better tuning, the rules restricted the carb choice to the same number of throats as OEM so a pair of webers was the same as a single 4 barrel........ .andyd
With the blower, the dual plane manifold isn't really doing anything. If you wanted to lower the assy to make more room for the intercooler you might concoct a simple single plane intake.
Zenith made a side-draft two-barrel that fueled a 935 CID military Hercules engine in 1958. I don't have CFM specifications. The carburetors are not cheap, but sometimes one will find one new old stock military surplus. The rebuilding kits also are not cheap, but at this writing, they are available mail order. Jon.
Comments on carburetors duly noted, thank you all. Gonna put that one aside for now and get back to stuff I know. Did .060 copper gaskets on the previous engine and couldn't be happier. A bit labor intensive but my labor is cheap. The first set has been on and off several times and the only challenge is rubbing off he Hi-Temp RTV. I used spray adhesive to hold the two copper sheets together, traced around the exhaust flange (which was also the template for the port matching) and then spent a gillion hours cuttin and filin. Another task that is labor intensive is detailing the crankshaft. Although some may argue that it is unnecessary, in the process I did discover several small metal fragments that were the result of grinding the journals. The extremely oblique angle of the oil supply holes relative journal surface yielded several "hangnails" that 'tho attached had potential to break off and embed in a bearing. Chamfering and polishing the oil holes assures good oil flow and is good insurance. A lotta scrubbin and cleanin too. Tomorrow I'll get to the final cleaning of the block before setting the crank in place.
You are my hero! I am blaming Gary (73RR) for my Poly fascination....pics of the 270 he built in my wife's 1952 Willys wagon attached. Also, the 315 which followed me home...on a run stand I am building. Let us know when those tall-deck cams go up for sale Sent from my SM-G892A using The H.A.M.B. mobile app
Those copper gaskets are beautiful they should be framed and hung up on the wall! They're a work of art but I would expect no less from you. Nice work.
Jack, I'm going to sit on the tall deck cams for now. ---------- Man this project lately has been like giving birth to an elephant! That said, I feel like I got over a hump yesterday. Slept real well too because I feel like I finally have a grip and can see the project thru. Surprised at the several differences between the low deck 241/270 and the 315/325 which my mentor Gary Stauffer has patiently explained. The block prep and clean is pretty standard. Something obscene about soap and water on cast iron,... 'tho the idea is to assure, no leftover grit from the machining. Had a bit of a hiccup on bearings that delayed progress. That worried me but I was able to score the correct size with only a week's delay. The particular challenge for my limited intellectual capabilities was assembling pistons and rods and rings. Ya know,....there are two diff. ways to put the pistons on the rods and diff. for the right and left banks. With 8 cylinders that's 32 opportunities to make a mistake And,....with 5 ring components for each of 8 pistons that 40 more opportunities to goof,...total 1280 chances to screw-up. I think I got it! Fingers crossed! I hope you enjoy the eye-candy as much as I do!
Finally got to some good stuff. Nothing like clean oily parts to assemble. Didn't think I had the cajones to get the mains torqued to spec so good friend and neighbor Mike lent me his BFing torque wrench. That sucker is 2 feet long and makes 90 ft/lbs a breeze.
I dug out an oil pan that was given to me some years ago, probably by the same guy who hacked up the 2x2 intake manifold. It was chrome plated and featured a rear sump via slicing thru the midsection and swapping the sump from front to back. It didn't want to fit without forcing. Spotted wear marks from the bolts on the oil pump so I had to do some major bashing on the pan for clearance. Not pretty but I believe, serviceable. Probably the highlight of the day was this package received from Summit Racing. Ordered just yesterday afternoon, July 3. It was on my doorstep this morning at 9:00 am. Is that service or what? Faced with doing some customizing, I ordered three pickups for the Melling pump, figuring I could make one of them work. Happy, it turned out that a 5/8" section and a Home Depot copper plumbing union got the pickup exactly where I wanted it. The clay shows 1/2" from sump to the bottom of the pan. The pickup cost all of $16.00 and I can return the two that were not used. Love Summit! Made my 4th of July.
Someone once said, "everything is connected to everything else". Man, that's 'specially true for Hot Rods. I've fantasized about 180 headers since my earlier abandoned attempt. That meant a different (rear sump) oil pan, which meant modified oil pickup, which meant a different dip stick and finding an accessible location that didn't place the dip stick into the rotating assembly and threaded past the pick up tube and still,....didn't affect configuration of the header primary tubes. Initially "sketched" with miscellaneous bits and pieces, I think I got it! Isn't pretty but sure is ugly! The dip stick will be accessible at the rear corner of the driver side head, next to the firewall.
I just want to say I really appreciate the time you are taking to document this build and discussing the challenges and wins. I have a 331 Hemi I hope to tear down and build back for a 33 chopped ford truck. This thread is giving me some much needed motivation (and potentially a false sense of confidence... hahahahaha).
I'd be a little bit worried about a copper joint in the oil pickup. The pickup sees a lot of vibration and copper has a tendency to work harden and get brittle under those conditions. I once used a brass nipple in an external oil pressure line connection and it eventually cracked.
I reversed my pan also. I sectioned it also because the car was going to be low. I made it so it was even with the bottom of the trans adapter. The sump was extended forward to get the oil capacity back. I used a common sbc pickup and welded a pipe threaded end on it to screw into the stock pump.The add on was where I could look inside and make sure nothing was going to come off. I also used a section of pipe for the dip stick boss. I just welded it into the pan side. A brass compression fitting let me adjust the Chevy dip stick up and down and it also made it easy to remove the tube to get the header off.
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