Jack Worstell Posted February 1, 2017 Share Posted February 1, 2017 Has anyone shaved the heads on a 1937 248ci to increase compression ? Jack Worstell jlwmaster@aol.com Link to comment Share on other sites More sharing options...
jenz38 Posted February 2, 2017 Share Posted February 2, 2017 Yes.... from my old 248 head I milled 4mm (four millimeter) off,without problems... But my engine instead was equipped with insert bearings from a '49 engine... If you have the oem babbits then I would givem a 2mm milling, if your engine is in good condition (good oilpressure,less oilconsumption ). The pushrods will compensate that with a normal valve adjusting. Link to comment Share on other sites More sharing options...
Jack Worstell Posted February 2, 2017 Author Share Posted February 2, 2017 Jenz38.........I guess the head you milled by 4mm was for a 1938 248 engine with Buick "domed" pistons ? ( I think the 1937 248 had flat pistons ??) Also....your mention of insert bearings...I guess you are referring to rod bearings from a 1949 ? Or both rod bearings and main bearings from a 1949 ?? Jack Worstell jlwmaster@aol.com Link to comment Share on other sites More sharing options...
pont35cpe Posted February 2, 2017 Share Posted February 2, 2017 Terrill Machine in DeLeon, Tx has inserted rods/bearings. 254 893 2610 Link to comment Share on other sites More sharing options...
jenz38 Posted February 2, 2017 Share Posted February 2, 2017 Jack ,my Engine have the original domed pistons...and it will work without problems , there is enough room in the head chamber because of the original low comp ratio of the old times... If you take the head off you will see how deep the chamber are. The rods are have babbit bearings up to '47-'48 I think... I'm had the luck to buy my car 13 years ago with the modern insert bearing rods inside. The 5 mains are alltime have inserts.. But if you hoped up your compression,it's possible that your rear main"seal" will start to leak..because of the higher internal crank housing pressure. Because the engines pre 39 have no rear main seal ,only a spiral there for dig the oil back into the pan. My engine runs great but starts then with extreme oil leaking over 2500 revs. If you have the chance,switch over to a complete block with insert bearings an real rear main seal... ?.. And no,you can't insert a seal in the previous 39 engines.there is no room on the crankshaft and also on rear main bearing housing to install one. It was 8 years ago as I had my original engine inside my car and had try to install the best gasket rear main seal for 248s..because they are sale this both rubber half moons for the Year '36 - '53 !!! ..that was wrong from the best gasket company I must learned ...,and nobody in the Forum (team buick) understand what I mean if I told them : "The set will NOT FIT in my '38 engine ..., under no circumstances "... As i came behind the secret of when buick realy switched over to a seal I send then a e-mail to best gasket for theyre mistake and correcting the starting year in theyr offer. Best regards..Jenz Link to comment Share on other sites More sharing options...
Steve_bigD Posted February 2, 2017 Share Posted February 2, 2017 My 1938 Special has a rear two piece rope seal as well as the spirals. The front timing cover and rear main rope seals as not as good as modern rubber ones but I rebuilt my engine over 30 years ago and still only have minor seepage at the seals. Steve D Link to comment Share on other sites More sharing options...
37_Roadmaster_C Posted February 3, 2017 Share Posted February 3, 2017 Jack, Egge can machine your rods to use inserts for what I considered to be a reasonable price. My engine is a 320 but I don't think that matters as to being able to do this. Call Egge and ask if this is of interest to you. Link to comment Share on other sites More sharing options...
LAS VEGAS DAVE Posted February 3, 2017 Share Posted February 3, 2017 If the reason for milling the head is to gain enough horsepower for the overdrive to pull your car with the higher gear ratio than the stock 4.44 gears you will be disappointed. The horsepower gain will be minimal and you would be much better off to return to the stock 4.44 gears. Your car will perform much better with the overdrive and the stock gears. My car has a real good stock engine and it pulls the overdrive good but it doesn't have enough power in top gear in overdrive to move up to a 3.90 ratio with as good as results as it is now. Milling the head for an additional 5 horsepower will not be a benefit, maybe 15 true horsepower or more would work. Link to comment Share on other sites More sharing options...
jenz38 Posted February 3, 2017 Share Posted February 3, 2017 (edited) I agree with you Dave.. Steve,..the front modern style seal don't make any problems and is easy to fix if necessary... But my rear main wasn't equipped with a groove for a rope...only the spiral and ahead of this a groove for collecting surplus oil that there drain back into the crankcase about a hole in the bottom . Theres a ball check in this, to prevent oil running back, if the front of engine is tilt up more than 18° . That all runs fine, if the crankcase pressure isn't raised up, that will result of a blown by at the piston rings. I realized now that main point here is ,more power for overdrive cruising. I can imagine ,that the much milled head /the higher comp , will have disadvantage at long distance at highway speed under heavy load (overdrive in a heavy ,full equipped 4 door sedan)... Can result in dangerous pinging and overheating.. In my case,a stripped series 40 coupe with 4.44 original rear axle it works amazing for accelerating an less load at 55 Mph. Edited February 3, 2017 by jenz38 (see edit history) Link to comment Share on other sites More sharing options...
Jack Worstell Posted February 3, 2017 Author Share Posted February 3, 2017 Thanks to all for the "food for thought". We have installed an overdrive in the 1937 Special and by the end of the month we expect to have the wiring done, switches installed etc etc .........we will be on the road with the new OD in 3-4 weeks we think. We expect the OD to be a major improvement....but since the car only has 100Hp, we anticipate not being able to take full advantage of the OD on the freeways. So we are thinking ahead and searching out ways to get more Hp. And Dave: your point about switching the axle ratio back to the original 4.4 from the current 3.9 is well taken....it's a possibility. I suppose the ultimate answer would be to keep the 3.9 ratio and switch out the engine to a 263ci. But this is a major undertaking that I'm not sure at this point we want to get into ( even if we could find a 263ci....) Jack Worstell jlwmaster@aol.com Link to comment Share on other sites More sharing options...
Ben Bruce aka First Born Posted February 3, 2017 Share Posted February 3, 2017 Jack, for what it is worth, I believe you will be OK with the overdrive. Sure, there will be times you will need to shift out of overdrive, but no big deal. I changed the rear gears in my '50 Special, with 248, from 4.1 to 3.36. I believe my '50 is probably a little heavier than your '37, . NO problem going down the road! I realize the final drive ratio is different than with OD, but guys use overdrive in Model A Fords. Glad you did it and look forward to future reports. Ben Link to comment Share on other sites More sharing options...
LAS VEGAS DAVE Posted February 5, 2017 Share Posted February 5, 2017 On February 3, 2017 at 2:39 AM, Jack Worstell said: Thanks to all for the "food for thought". We have installed an overdrive in the 1937 Special and by the end of the month we expect to have the wiring done, switches installed etc etc .........we will be on the road with the new OD in 3-4 weeks we think. We expect the OD to be a major improvement....but since the car only has 100Hp, we anticipate not being able to take full advantage of the OD on the freeways. So we are thinking ahead and searching out ways to get more Hp. And Dave: your point about switching the axle ratio back to the original 4.4 from the current 3.9 is well taken....it's a possibility. I suppose the ultimate answer would be to keep the 3.9 ratio and switch out the engine to a 263ci. But this is a major undertaking that I'm not sure at this point we want to get into ( even if we could find a 263ci....) Jack Worstell jlwmaster@aol.com Jack, there is a guy in Northern that has a nice 263 motor on a stand, he is asking 600 dollars. His name is Mark Simmons, he is a member of the ANTIQUE AUTOMOBILE CLUB forum. I was going to buy that motor as a project and a spare for our car but in reality I don't think I will ever wear ours out. I have his phone number if you need it. Link to comment Share on other sites More sharing options...
LAS VEGAS DAVE Posted February 5, 2017 Share Posted February 5, 2017 On February 3, 2017 at 4:58 AM, First Born said: Jack, for what it is worth, I believe you will be OK with the overdrive. Sure, there will be times you will need to shift out of overdrive, but no big deal. I changed the rear gears in my '50 Special, with 248, from 4.1 to 3.36. I believe my '50 is probably a little heavier than your '37, . NO problem going down the road! I realize the final drive ratio is different than with OD, but guys use overdrive in Model A Fords. Glad you did it and look forward to future reports. Ben Ben keep in mind that an overdrive raises the the overall ratio by a third. If the speedo shows 40mph the car is doing close to 60mph. That is with stock gearing. With this set up my car does not have the power to pull steep hills for a long distance, if I kick it out of overdrive it goes right up the same steep hill. The Model A guys keep the stock Model A rear ratio which is even lower than our Buicks and just install an overdrive. All overdrives are not equal but the Borg Warners give a 30% increase overall. Link to comment Share on other sites More sharing options...
jenz38 Posted February 6, 2017 Share Posted February 6, 2017 I had done it also with a 263 in my car.. But remember,the 37s are always 3 speed manual cars ..and the younger 263 equippeed cars are already mostly automatics ... because of the Crank flange from an automatic engine will doesn't fit onto a manual box flywheel an have also no pilot bearing area. Link to comment Share on other sites More sharing options...
Recommended Posts
Create an account or sign in to comment
You need to be a member in order to leave a comment
Create an account
Sign up for a new account in our community. It's easy!
Register a new accountSign in
Already have an account? Sign in here.
Sign In Now