austinsailor Posted February 11, 2011 Report Posted February 11, 2011 You guys have been very helpful with answers as I tackle this 251. I got it back from the machine shop, freshly bored and pistons fitted. My job this weekend was to get all the old broken, bent and rusted manifold studs out, the water distribution tube out and do whatever porting I want done. I'll take it back to him the first of the week and he'll start on the valves. Got all the studs out and the water distribution tube out, now I'm working on cleaning up the ports. Which leaves me with a question on porting. I'll have a new gasket set in the morning, tonight all I had was one of the little ones that fits the end exhaust ports. But I ground those two out to fit the gasket and smoothed them out going in as far as the valve guide. In studying it, it appears that the big bulge sticking out from the valve guide is really blocking a lot of exhaust path. I could easily remove a great deal of it. The guides are set down about 1/4 inch into the hole, leaving only cast iron sticking up, with the ridge going across. Removing much of that would seem to greatly improve exhaust flow. Is this advisable? Any thoughts or experience with this? Am I even making any sense? Quote
greg g Posted February 11, 2011 Report Posted February 11, 2011 For cooling reasons, I would leave some of that meat around the valves. Smoothing it out but leaving the structure. Most folks just enlarge the ports to the size of the gasket opening, then smooth the rest of the passage. How are you protecting your new parts from you grinding debris?? Pictures??? Quote
greg g Posted February 11, 2011 Report Posted February 11, 2011 Checkout this Hamb thread. http://www.jalopyjournal.com/forum/showthread.php?t=315555&highlight=rebuilding+plymouth+flathead&page=6 His porting adventure starts at Post 118 or so. I don't think he ever finished. and kinda disappeared. Also there is an imbedded link to MOPERSLED's thread also. Good info in both. Quote
Booker T Posted February 11, 2011 Report Posted February 11, 2011 Checkout this Hamb thread. http://www.jalopyjournal.com/forum/showthread.php?t=315555&highlight=rebuilding+plymouth+flathead&page=6His porting adventure starts at Post 118 or so. I don't think he ever finished. and kinda disappeared. Also there is an imbedded link to MOPERSLED's thread also. Good info in both. Yeah, sad that he never completed the project...or at least never completed the thread...lots of great information in there... Quote
dezeldoc Posted February 11, 2011 Report Posted February 11, 2011 Checkout this Hamb thread. http://www.jalopyjournal.com/forum/showthread.php?t=315555&highlight=rebuilding+plymouth+flathead&page=6His porting adventure starts at Post 118 or so. I don't think he ever finished. and kinda disappeared. Also there is an imbedded link to MOPERSLED's thread also. Good info in both. Greg, I remember following that thread then poof he vanished! here is the last time he was signed on; Last Activity: 02-02-2009 09:27 PM. I wished he had finished and updated it, would have liked to seen the outcome. Quote
greg g Posted February 11, 2011 Report Posted February 11, 2011 I think that might have been to post his classified selling off. Wow 2 year already. Perhaps had a reversal of fortune work wise. Was looking forward to more stuff also. Quote
Cpt.Fred Posted February 11, 2011 Report Posted February 11, 2011 true, it's sad it doesn't continue... like a good book missing the last quarter of pages... or a triology without the last part. austinsailor, i've been following your postings with great interest since i want to do a similar thing on a 230 one day. photos would be great and i hope everything turns out nice on your engine! Quote
austinsailor Posted February 11, 2011 Author Report Posted February 11, 2011 (edited) I'd seen that thread some time ago. I need to spend some time looking at details again. He's working on a short Plymouth block, mine is a long truck block. On his, the guides stick far above the place I'm talking about and I don't know if it's because of the different block or because a different part was used in rebuilding. But even without the guide difference, the restrictive part I'm talking about is much more pronounced on mine. The two pictures are from his. In the view looking into the port of his motor, the boss around the guide is not nearly as restrictive before porting as mine. On mine the guide is set down nearly 1/4" below the cast, his is well above it. Mine also has a raised area completely across it. In the picture looking down he has removed it almost to the guide. It looks similar to what I have in mind, but mine didn't start out like his. I need to get some pictures tonight. I think I can, not sure how well my camera will do with that. As to cleaning, once I get done, it'll go back to the machine shop and he'll do the valves. Then it'll go in the tank and get a serious cleaning. The pistons are still at his shop. Once the cam comes back from Edgerton, probably next week, we'll install the cam bearings, deck it and clean it up completely. I will have to say it's much easier and quicker to remove the metal in the ports than I thought it would be. It goes pretty quick. Edited February 11, 2011 by austinsailor Quote
austinsailor Posted February 11, 2011 Author Report Posted February 11, 2011 My pictures don't seem to show things as good as the one on the HAMB, but here they are. Quote
Tony WestOZ Posted February 11, 2011 Report Posted February 11, 2011 Cannot say I have ever seen valve guides sit that low in a 251 block. How far do the protrude down on the bottom side? I was wandering if they have been pushed to far in. Quote
greg g Posted February 11, 2011 Report Posted February 11, 2011 I would agree, I think they should be sitting proud of the top side of the casting. Quote
1941Rick Posted February 11, 2011 Report Posted February 11, 2011 Is that the block "after" boring and piston fitting? If so , could you not find a shop to boil the block to clean it up.....when I did my 218 last winter I ported it out to the gasket and gave it a little bit of a polish....I read on one of these forums that there is no need to get to fancy as you may go backwards or have no effect at all. Quote
austinsailor Posted February 11, 2011 Author Report Posted February 11, 2011 it is a truck engine with sodium filled valves. could that be the difference? and, yes, he'll clean the block when all the work is done. as to the guides, he's putting in some sort of sleeves. seems to be the way to do it now. when I tore down the motor it had heavy layers of oil crude in the intake passages between the guide and valve. this tells me it was sucking oil through the intake valve guides. I asked about using those umbrella type seals you'd put on an ohv motor. As I guessed, he said they wouldn't stay in place to seal. he said years ago one of the companies made a spring to go inside the valve spring to hold them up. he also was willing to press out the guides and machine a lip to hold on another kind of seal, then re-install them. I doubt either is needed on a fresh motor, and I could always tear it down and do it, just adding a gasket set to the cost. Any thoughts on this? Oh, Edgerton has my cam done, things are coming together! Quote
austinsailor Posted February 13, 2011 Author Report Posted February 13, 2011 For better or worse, I'm done with the block and it's in the truck, ready to return to the machine shop in the morning. Here are before and after photos. Quote
greg g Posted February 13, 2011 Report Posted February 13, 2011 are you going to match the manifolds to the gasket also??? Quote
austinsailor Posted February 13, 2011 Author Report Posted February 13, 2011 Yes, once I figure out what I'm going to use. Quote
heavytlc Posted March 4, 2011 Report Posted March 4, 2011 Here are some pictures of the porting job on my 251. The valves, guides,springs keepers are not Desoto. Think Late model. My engine builder did some trick stuff. I guess I should post a full thread on the build soon. The last picture is of the pistons that replaced the stock ones. This is all going in my 1953 Desoto 2door sedan. Mild custom, but we are going to try to run it in the xo class at Maxton for an East Coast Timing Association record this year. Quote
austinsailor Posted March 4, 2011 Author Report Posted March 4, 2011 I'm going to build another one of these days. I'd be real interested in hearing more about yours, as would many others, I'm sure. Your porting was much more drastic than mine. I was a bit afraid of going too far, this being my first try and having no way to know how thick the metal was. I might saw up a block just to get an idea of what is there for the next time. There is bound to be a junk block around. Thanks for posting those pictures. Quote
heavytlc Posted March 4, 2011 Report Posted March 4, 2011 My good friend Lee Schwartz Did the porting. He runs Flow Tech in Asheville Nc. This turned into a radical build, but with highway manors a major concern. I will start my own thread, just wanted to post porting pics here:D Quote
BeBop138 Posted March 4, 2011 Report Posted March 4, 2011 VPW has new guides if you have any concerns.....Lee Quote
Don Coatney Posted March 4, 2011 Report Posted March 4, 2011 Here are some pictures of the porting job on my 251. The valves, guides,springs keepers are not Desoto. Think Late model. My engine builder did some trick stuff. I guess I should post a full thread on the build soon. The last picture is of the pistons that replaced the stock ones. This is all going in my 1953 Desoto 2door sedan. Mild custom, but we are going to try to run it in the xo class at Maxton for an East Coast Timing Association record this year. What valves are you using? I installed shiverlay valves in my 53 Desoto engine. Quote
Andydodge Posted March 4, 2011 Report Posted March 4, 2011 HeavyTLC.......where did the pistons come from? it looks like a much newer design with a much shorter skirt.......are they custom made or what?........what bore is your engine?......thanks, andyd Quote
Cpt.Fred Posted March 4, 2011 Report Posted March 4, 2011 that is some serious business going on here... i lurk and learn! one of these days... Quote
heavytlc Posted March 4, 2011 Report Posted March 4, 2011 (edited) Ls1 valves, beehive springs, retainers. Weisco pistons, 3 ring package, coated skirts, Bushed rods for smaller wrist pins. I really need my own thread. The car was a beautiful 2 owner. I was just going to make a nice mild custom. It has turned into a much larger project. 3x1, on a george asche aluminum intake, split manifold, aluminum head, Plymouth overdrive from Mr Asche, four wheel disks, chrome dash and garnish, smoothed bumpers, Frame off powder coated chassis, inner fenders, hand made cloth wrapped wiring harness. It has lots of neat tricks. Staying 6volt positive ground. Other than brakes, 8.8 rear axle, a little lowering it is bone stock, using everything it came with, just replating and changing the level of fit and finish. Kepping the hood bird, door handles, and belt line trim, everything else is shaved. No patch panels, no,0% never had any rust, clean car. I was going for a 4-5year old car that got the mild custom treatment in 1957-58. Imagine A car that A hot shot traveling salesman would drive, if he could not afford a new Cadillac. Picture of the chassis back from powder coat, and a pic of what a nice car I started with. I should have just drove it, it was super nice, only needing some interior clean up. I hope to have a nice custom, with a land speed record in the ETCA maxton 2011 series this year. Edited March 4, 2011 by heavytlc insert pics Quote
Andydodge Posted March 4, 2011 Report Posted March 4, 2011 Heavy(?)........thats one serious flat 6, with those pistons what compression will you be running?, also are you using the stock head?........details,details................lol......inquiring minds want to know everything........lol.......you are the first person I've seen who is running non stock type pistons and I am impressed.....have you any info, feedback from others who have done so?.........am curious how the lack of the full skirt will go.........anyway any and all details will be gratefully devoured...........many thanks.......Andy Douglas. Quote
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