Good bye Locost 7 Hello GT40!!
- Thread starter RacerDave
- Start date
... do the pistons have or did you drill the pistons from ring groove to pin bore for pin oiling and have you done a trial fit for valve to piston clearance with cam/heads/valves of choice?If your lucky your pistons 'might already have the vertical drilling in black that goes thru from bottom to top of pin boss, if thats the case all you have to do is drill from ring groove to intersect with top portion of that drilling as per LH of that pic.
If you have no drillings you have three options-
1. drill as per RH side of pic in 'red', [ you will need to remove pistons from rods to do this, is it worth the risk of potential piston damage on removal from rod/pin]?
2. Simply drill straight across from the oil ring groove without intersecting to the pin bore- at least this would ensure that the inner end of the pin boss which receives the greatest pin load will get plenty of oil-even if it is deflected back from the rod small end.
3. Cross all your appendages & hope! like most of the other guys seem to.... just that with your 3.85 crank & std 351w rod you have upped the work load & while you got away with it in the Saturday night dirt car the GT40 with the likelihood that you might spend more time at full throttle for longer periods of time might burst the bubble.
If you have no drillings you have three options-
1. drill as per RH side of pic in 'red', [ you will need to remove pistons from rods to do this, is it worth the risk of potential piston damage on removal from rod/pin]?
2. Simply drill straight across from the oil ring groove without intersecting to the pin bore- at least this would ensure that the inner end of the pin boss which receives the greatest pin load will get plenty of oil-even if it is deflected back from the rod small end.
3. Cross all your appendages & hope! like most of the other guys seem to.... just that with your 3.85 crank & std 351w rod you have upped the work load & while you got away with it in the Saturday night dirt car the GT40 with the likelihood that you might spend more time at full throttle for longer periods of time might burst the bubble.
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Better to be lucky than good. The pistons are drilled like the left side of photo. So what diameter should the hole from the oil ring be? should the be a slight angle on the hole towards the bottom of the piston even though it is shown as straight?
Now once holes are drilled oil will travel from oil ring land to wrist pin holes.
Now once holes are drilled oil will travel from oil ring land to wrist pin holes.
Those look like 3/16" wide oil ring grooves so a 3/32" or 1/8" drill will be fine, try to drill on the bottom side of the oil groove, [wont matter if you touch the bottom side of the oil ring groove- BUT under no circumstances allow the drill to mark the upper groove side ].
Just drill it straight in to intersect the factory vertical drilling, the pin bore is far enough away from the oil ring groove on those 302 pistons, being hyper eut pistons I think they should be all alloy, some earlier plain jane versions have an 'invar strut' ( steel reinforcing insert) that might scare you while drilling the hole. take care drilling the holes and use a new drill after every three pistons to reduce the worry factor if doing it freehand.
Just drill it straight in to intersect the factory vertical drilling, the pin bore is far enough away from the oil ring groove on those 302 pistons, being hyper eut pistons I think they should be all alloy, some earlier plain jane versions have an 'invar strut' ( steel reinforcing insert) that might scare you while drilling the hole. take care drilling the holes and use a new drill after every three pistons to reduce the worry factor if doing it freehand.
Finished up a front hub modification today on lunch break. Installed the hub and the brake hat with disc.
Here is how my wheels look with the AP RACING 4 piston calipers and the 60 vane J hook brake discs look!
My 40 has mustang II front spindles using Ford Granada hubs which I removed the stock brake disc with my Bridgeport mill. Machined the brake hats to fit the 11.75 x 1.25 AP Discs. The calipers are AP racing billet 4 pistons with 1.875 ,1.75" staggered piston sizes. This is just a test fit I may upgrade to the new AP Racing Essex Parts version CP 5060 six piston like we have been using on the new Z06 corvette kits
Here is how my wheels look with the AP RACING 4 piston calipers and the 60 vane J hook brake discs look!
My 40 has mustang II front spindles using Ford Granada hubs which I removed the stock brake disc with my Bridgeport mill. Machined the brake hats to fit the 11.75 x 1.25 AP Discs. The calipers are AP racing billet 4 pistons with 1.875 ,1.75" staggered piston sizes. This is just a test fit I may upgrade to the new AP Racing Essex Parts version CP 5060 six piston like we have been using on the new Z06 corvette kits
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Hey Dave,
You are plugin away on the car real well. Good to see you got some motivation going. Won't be long at this pace. Probably spring?? I am trying to build some solar heaters for my work space so I can get some motivation of my own. 13 degrees today when I got up.
Bill
You are plugin away on the car real well. Good to see you got some motivation going. Won't be long at this pace. Probably spring?? I am trying to build some solar heaters for my work space so I can get some motivation of my own. 13 degrees today when I got up.
Bill
Hi Bill:
Actually a goal is to have it in my buddies car show in the fall. It was cold here today also. Space Heater in Garage is working over time. The Motivation is for motor rotations in a few weeks I hope. I think if I hear it run I will feel better .
Jac : This is what I come up with to drill those oil holes you mentioned. 4 down 4 to go.
Actually a goal is to have it in my buddies car show in the fall. It was cold here today also. Space Heater in Garage is working over time. The Motivation is for motor rotations in a few weeks I hope. I think if I hear it run I will feel better .
Jac : This is what I come up with to drill those oil holes you mentioned. 4 down 4 to go.
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Yes thats always a 'high' risk with pressed pins. Best you leave it as is for now & just get it running- time for detail rethinks later!
For the 351w based motor you have the standard pump is plenty, oil pressure should run around 55/60 lb hot above 2500 RPM, might drop down around ~20 lb at idle etc.
It is vital to check even a new pump for clearances at get these down to minimums, and the pump pressure passage polished/matched from pump to oil filter pad, its amazing how much restriction & pressure is induced in that area if you dont. A 'priority' line from filtered side of filter block to the rear of the main gallery is also a good idea. No fancy oil pump drives etc reqd with these parts. A tiny ~0.020" hole in the front of the lifter gallery plug behind the dizzy gear helps to bleed the lifter gallery & extra lube to the dizzy gear.COLOR]
It is vital to check even a new pump for clearances at get these down to minimums, and the pump pressure passage polished/matched from pump to oil filter pad, its amazing how much restriction & pressure is induced in that area if you dont. A 'priority' line from filtered side of filter block to the rear of the main gallery is also a good idea. No fancy oil pump drives etc reqd with these parts. A tiny ~0.020" hole in the front of the lifter gallery plug behind the dizzy gear helps to bleed the lifter gallery & extra lube to the dizzy gear.COLOR]
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Attached pic shows where oil line fits into rear of main gallery, where the line passes thru block adjacent to oil pan at rear you could use a bulkhead fitting if desired. Front end of line MUST source filtered oil, eg where it exits center of filter. Can use -4 line if you cannot source the 1/4" npt right angle adapter. This line is in addition to the factory oil galleries.
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Hi Dave, stop complaining about the cold, I'm in Western Australia at work and I wish it was cold, we've have 40c and thunderstorms for over a week and our rig site is a swamp of red clay, any way just looking through you log and you making good progress, front brakes and hubs are next on my list for the front so post some pics when your into it so I can get some ideas. cheers Leon.