janan5243 Posted July 18, 2014 Author Report Share Posted July 18, 2014 would appreciate all opinions or advice. would it be foolhardy to install a milled head on my engine based on compression readings posted. also, are there timing marks on the damper pulley? tore the side of my arm up this evening trying to clean damper, looking for marks. Pulley has two flat areas, thought I saw some marks on one of the flats. Once again, I realize the final decision is mine. Quote Link to comment Share on other sites More sharing options...
greg g Posted July 18, 2014 Report Share Posted July 18, 2014 The flat spot on the crank pulley is to ease the installation of the fan belt, provides clearance so you don't have to force the belt. Go to carnut.com, go to the specs section. Take not of the engines displacement and compression ratio as regards total HP. As fuel got better cr got tighter ad HP went up. I doubt that cams were changed, so I would venture to guess the biggest contributor to increased HP was pretty much more squeeze. So if you wan the Spit fire head and it provides more CR go for it. If you wan more CR for cheap just take you head to a machine shop and shave .060 to .090 off it. Quote Link to comment Share on other sites More sharing options...
Plymouthy Adams Posted July 18, 2014 Report Share Posted July 18, 2014 greg g, on 17 Jul 2014 - 9:44 PM, said:The flat spot on the crank pulley is to ease the installation of the fan belt, provides clearance so you don't have to force the belt. Go to carnut.com, go to the specs section. Take not of the engines displacement and compression ratio as regards total HP. As fuel got better cr got tighter ad HP went up. I doubt that cams were changed, so I would venture to guess the biggest contributor to increased HP was pretty much more squeeze. So if you wan the Spit fire head and it provides more CR go for it. If you wan more CR for cheap just take you head to a machine shop and shave .060 to .090 off it. IF....you know for certain what the current CR is.....not knowing, guess that it would be fine and without the benefit of actually CC'ing the head...it would not be good advice to mill the head willy nilly..what would happened if say this has already been done in the past? Just spitballing here but these are question you need to answer prior to moving onto any intended speed trick/engine mod Quote Link to comment Share on other sites More sharing options...
greg g Posted July 18, 2014 Report Share Posted July 18, 2014 I guess I shoulda mentioned that Stock head was assumed. Quote Link to comment Share on other sites More sharing options...
Don Coatney Posted July 18, 2014 Report Share Posted July 18, 2014 It is also advisable (once the head is off) to measure your actual valve lift as pictured below so you know how much room you have to play with. I have installed a modified cam in my engine so my lift is higher than factory. Pictured below are the measurements of the Spitfire head I have. I do not know if this head has ever been milled but by doing the measurement pictured above I know it was safe to shave it. And lastly not all dampers have good timing marks. Quote Link to comment Share on other sites More sharing options...
janan5243 Posted July 18, 2014 Author Report Share Posted July 18, 2014 Greg G. Engine is totally original. Never been apart. so I have to assume head is stock. Don: is your head for sale or is it a spare? I just got off the phone with man I bought car from. He was second owner. got car from estate with 24,000 miles on it. He had it 25 years & put 50,000 on it. He restores cars ,particularly Franklins. You all would love to see his collection. He has a 1939 Desoto 4 door for sale. Like my car totally original except for paint. Anyway back to my saga. Found out from him that there are marks on damper. I realize that increasing CR at this point will shorten life of an old engine but I doubt I will ever put more than 5,000 miles a year on it. When engine needs help I would like to be able to send it to Robert Asche or the like to have it rebuilt. Actually, if I sell my hardware store, I would like to do as much as I could myself. To make a short story long, I'm going to acquire a head, have it milled & install on present engine. I'll keep mine for a spare. Thanks for all advice. Then a dual carb setup & a rear end upgrade. There are a few salvage yards to get rear end from. Then a front disc conversion over winter. Quote Link to comment Share on other sites More sharing options...
Don Coatney Posted July 18, 2014 Report Share Posted July 18, 2014 My head is not for sale. I have plans to install it on my engine sometime. Quote Link to comment Share on other sites More sharing options...
janan5243 Posted July 18, 2014 Author Report Share Posted July 18, 2014 54 Illinois has one he offered. I asked about it twice in posts but I guess he hasn't been back on. I sent him a message. Any hints on other places? Quote Link to comment Share on other sites More sharing options...
janan5243 Posted July 19, 2014 Author Report Share Posted July 19, 2014 54 Illinois & I have made contact. He is checking shipping cost to me. Best place to get gasket set ? I've seen reference that it's wise to stay from NOS sets. I found my timing marks. Damper is 10 before to 10 after in 2 degree marks with TDC marked. Going to time it today along with new points, condenser cap & rotor. Had weird experience last night. Was accelerating from stop in 3rd. Car Backfired twice, happened to look in mirror puff of blue gray smoke , then nothing ran fine rest of trip. Quote Link to comment Share on other sites More sharing options...
Don Coatney Posted July 19, 2014 Report Share Posted July 19, 2014 Do you by chance have an exhaust leak? An exhaust leak will allow fresh air to enter the exhaust pipe and any unburned fuel in the exhaust system can and will ignite and explode with a loud bang expelling any carbon deposits that have accumulated in the exhaust system visibly out the tailpipe. Quote Link to comment Share on other sites More sharing options...
janan5243 Posted July 19, 2014 Author Report Share Posted July 19, 2014 I don't hear any leaks by manifold or engine pipe. Just installed a new muffler & tailpipe. This definitely sounded like a backfire thru carb. Did it once more in hi gear but no smoke. I was fooling around with timing. Today I put distributer tune up w/ new cap & set timing with light. Have it between 4-5 degrees BTDC. Definitely starts better. Will find out on way home from store. The smoke looked like oil smoke. Going to Blenheim/Gilboa Power Authority for car show tomorrow. Put on by local AACA. chapter. Should be 200-250 cars. Quote Link to comment Share on other sites More sharing options...
54Illinois Posted July 24, 2014 Report Share Posted July 24, 2014 I tried to upload photos...but they are too big. make me an offer, as shipping will be a lot! Quote Link to comment Share on other sites More sharing options...
janan5243 Posted July 25, 2014 Author Report Share Posted July 25, 2014 Do you know how much head weighs? What is width of head? I think, from Don's measurement, it is about 2" thick & 25" long. Will try to find out if USPS will ship in one of their boxes. Quote Link to comment Share on other sites More sharing options...
janan5243 Posted July 25, 2014 Author Report Share Posted July 25, 2014 54 Illinlos; you asked about other head. That was a local guy so no shipping but I was not buying till I checked market & prices. I'm sure we can come to a reasonable solution. Quote Link to comment Share on other sites More sharing options...
janan5243 Posted July 25, 2014 Author Report Share Posted July 25, 2014 54; ballpark # based on 70lbs, 2"x 12"x 25" from zip 60018: $70.00. So the deciding factor: what do you want for head? You can reply via email if you want. Quote Link to comment Share on other sites More sharing options...
54Illinois Posted August 4, 2014 Report Share Posted August 4, 2014 I just got back in town from vacation in the stix...let me see if I can run the head over to the P.O. tomorrow (if you still need it) to verify shipping. I apologize for any problems! Quote Link to comment Share on other sites More sharing options...
janan5243 Posted August 5, 2014 Author Report Share Posted August 5, 2014 54; How much does head way? USPS only does up to 70 lbs. I sent you a message with a ballpark quote for UPS. Jim Quote Link to comment Share on other sites More sharing options...
54Illinois Posted August 6, 2014 Report Share Posted August 6, 2014 Not sure on weight...be in touch. Quote Link to comment Share on other sites More sharing options...
janan5243 Posted August 8, 2014 Author Report Share Posted August 8, 2014 where can you find out the stock thickness of a spitfire head. I spoke to the guy that prompted this whole thread & it turns out he bought the head from George Ashe already milled but He doesn't remember how much. He also has a triple carb manifold. Are they much harder to set up than a double carb? Is it worth using triple carbs? Quote Link to comment Share on other sites More sharing options...
Plymouthy Adams Posted August 8, 2014 Report Share Posted August 8, 2014 time to CC the head..if not checked in this method one is merely guessing... Quote Link to comment Share on other sites More sharing options...
janan5243 Posted August 8, 2014 Author Report Share Posted August 8, 2014 OK Plymouthy, Splain to this beginner what CC means. Quote Link to comment Share on other sites More sharing options...
Plymouthy Adams Posted August 8, 2014 Report Share Posted August 8, 2014 measuring the volume of the head chamber in CC's that is the only way to establish the CR and know if or if not head has been and to what extent unless you know the very history of the component..you have to also consider the below deck position of the piston in volume and that also of the compressed gasket... I believe if you do a search on the forum for this you should find where I have posted the established below deck and gasket measurements to assist you in your calculations... Quote Link to comment Share on other sites More sharing options...
Don Coatney Posted August 8, 2014 Report Share Posted August 8, 2014 where can you find out the stock thickness of a spitfire head. Re-read posting #30 on this thread. I believe the head I measured was never milled but one can never be sure. Quote Link to comment Share on other sites More sharing options...
Plymouthy Adams Posted August 8, 2014 Report Share Posted August 8, 2014 long time ago I tried to compile a list of head data by dimension and part number for future comparisons...it did not pan out, little feedback from the forum... Quote Link to comment Share on other sites More sharing options...
greg g Posted August 8, 2014 Report Share Posted August 8, 2014 was your compression test done cold and dry or warm and with some oil added? Quote Link to comment Share on other sites More sharing options...
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