Is there a minimum recommended engine-to-firewall clearance? I have the 235 sitting in my '36, and it's pretty darn close to the firewall in the back. There's a little bit of clearance but not much. I could probably cheat the engine forward slightly if need be.
'57 GMC 102, Original 347 V8, HydraMatic, 3.08 rear gear, added A/C, disk front brakes, HEI, AFB carb, '98 Honda Black Currant paint. T-boned and totaled 10/12 '52 GMC 152 Stake Bed, Original 228, SM420, added A/C, HEI, disk front brakes, '67 Chev 3.55 rear gear. Gets used as a real truck.
It is very accurate for motor to firewall clearance. Just like torque a bolt til your elbow clicks. Works with SAE or Metric. There's no guess work in automobile mechanix. This info is dependent on whether you are fasting or not.
In all seriousness, I don't know how much these motors move under torque, or as motor mounts wear. I'll just slide it forward 1/4 or 1/2 inch. Can't go too far, though for fan clearance, plus using stock pedals.
The engine movement under torque is basically side to side rather than fore to aft so if you have clearance it should be good. That being said it is a balance between rear clearanc and fan clearance and I prefer to have more fan clearance so tend to bias toward the rear.
fore and aft are only used in nautical terms. I don`t get why they are used here. My dad was a Coast Guard Flotilla Commander and would never use those words out of context. Just sayin
We were doing so well and then WICruiser has to come in and give a good straight answer.
'57 GMC 102, Original 347 V8, HydraMatic, 3.08 rear gear, added A/C, disk front brakes, HEI, AFB carb, '98 Honda Black Currant paint. T-boned and totaled 10/12 '52 GMC 152 Stake Bed, Original 228, SM420, added A/C, HEI, disk front brakes, '67 Chev 3.55 rear gear. Gets used as a real truck.
I bolt the engine down on the mounts and chain a 6 foot long pry bar to the engine. I give it a HARD pull toward the passenger's side. If the engine doesn't touch the firewall, it's good to go. Torque reaction is always toward the passenger's side. Sometimes a little BFH massage to the firewall sheet metal at the closest point of contact is all that's needed. Jerry
"It is better to be silent and be thought a fool than to speak and eliminate all doubt!" - Abraham Lincoln Cringe and wail in fear, Eloi- - - - -we Morlocks are on the hunt! There is nothing noble in being superior to your fellow man; true nobility is being superior to your former self. - Ernest Hemingway Love your enemies and drive 'em nuts!
There is some "force" on acceleration. Force on the motor mount rubber. The force is called momentum or weight transfer. 1/2" clearance is a good minimum. It is usually the distributor that is close. Then the valve covers.
The engine movement under torque is basically side to side rather than fore to aft so if you have clearance it should be good. That being said it is a balance between rear clearanc and fan clearance and I prefer to have more fan clearance so tend to bias toward the rear.
Yes, the side to side is what I'm concerned with. The passenger side is close on the corner. Can't move the engine over very much but sliding it forward will give a little bit more clearance around the curve. Maybe I can get a slight bit of lateral movement too.
I bolt the engine down on the mounts and chain a 6 foot long pry bar to the engine. I give it a HARD pull toward the passenger's side. If the engine doesn't touch the firewall, it's good to go. Torque reaction is always toward the passenger's side. Sometimes a little BFH massage to the firewall sheet metal at the closest point of contact is all that's needed. Jerry
Jerry, good tip. I'll give that a try. BFH may be necessary. But I guess if it needs more clearance, the engine will make it on it's own. LOL
Unless you plan on pulling stumps, I doubt that a 235 engine will move enough to hit anything where it is located in your pic. If it does, it will leave a mark to indicate where to hit it with a hammer or pry the metal down with a log crowbar.
1952 5-window - return to "as built" condition | 1950 3100 with a 235 and a T-5 transmission
My â37 with original 216 is pretty tight. The problem youâll have with the 235 will be the radiator clearance.
Larry Old maná Old trucká neither one goes very fast. All you need in life is TIME, PATIENCE and MONEY. If you are missing one component, you'll need an abundance of the others two.
Larry, that's why I can't really go forward much. I bought the plate from Pre-68 Dave to use the earlier water pump. Even with that I'll likely have less then .75" of clearance. Probably closer to .5"
Keep in mind, you need enough clearance to change the fan belt.
Phil Moderator, The Engine Shop, Interiors and Project Journals
1952 Chevrolet 3100, Three on the Tree, 4:11 torque tube Updated to: â59 235 w/hydraulic lifters, 12v w/alternator, HEI, PCV and Power front Disc Brakes Project Journals Stovebolt Gallery Forum