Drive Train Angles

[MindlissMetalfab]

I have a 68 521 that a previous owner had 'swapped' an L16 into. The swap was done with some farmer bojangling so I didnt even bother to check the angles of the engine and trans when I pulled it out because you could tell it was janky. Now I'm putting it back together with a new front frame clip so I need to build motor and trans mounts before I can start my new floor and firewall.

 

I know the engine should be level side to side but it seems like everything is on a different plane. Should I make sure the centerline between the cam and crankshaft pulleys is perpindicular? Or go with the valve cover? oil pan?

 

Also need to know the front to back angle, generally I would assume 2° down on the pinion should be OK but i just want to double check.

[datzenmike]

Angle in has to equal angle out. OR the bend at the tranny has to equal the bend at the differential. The less bend the better.

A bend in a drive shaft does not turn at a constant speed so having two equal bends will tend to equall this out.

[72240z]

Angle in has to equal angle out. OR the bend at the tranny has to equal the bend at the differential. The less bend the better.

A bend in a drive shaft does not turn at a constant speed so having two equal bends will tend to equall this out.

 

Less is good but I think it should be noted universals require at least 1 degree of angle too keep the needle bearings spinning, or they fail. I would keep it under 3 degrees to avoid vibration and wear issues. 1-1.5 degrees is ideal and good for safe running any any rpm the engines going to run.

 

Here is a decent article from drivetrain.com

[MindlissMetalfab]

Like I said I'm not overly worried about the tailshaft angle. My pinion is set 2° up so I will set the tailshaft at 2° down.

 

Its the side to side of the motor I'm most worried about as I'm not totally sure what should be 'level; since the valve cover, oil cap and oil filler all seem to be on different planes...

[RoadRace]

Like I said I'm not overly worried about the tailshaft angle. My pinion is set 2° up so I will set the tailshaft at 2° down.

 

Its the side to side of the motor I'm most worried about as I'm not totally sure what should be 'level; since the valve cover, oil cap and oil filler all seem to be on different planes...

 

using the valve cover and oil cap as a reference plane is generally not the way you install an engine - for so many reasons that i will not go into here (not gonna touch the oil filter ref...). Also, the engineers at datsun did all the work for you, so using OEM parts is the best way to ensure your motor and trans are located correctly. sourcing a crossmember, motor mounts and a trans mount should be pretty easy with the help from the guys here on the board.

 

the L series engines are 'slant'-type engines and lean to the side.

[INDY510]

 

Yeah.... uh.... the valve cover is not level...... it leans towards the passenger side.

I don't know the exact angle....

:huh:

[MindlissMetalfab]

using the valve cover and oil cap as a reference plane is generally not the way you install an engine - for so many reasons that i will not go into here (not gonna touch the oil filter ref...). Also, the engineers at datsun did all the work for you, so using OEM parts is the best way to ensure your motor and trans are located correctly. sourcing a crossmember, motor mounts and a trans mount should be pretty easy with the help from the guys here on the board.

 

the L series engines are 'slant'-type engines and lean to the drivers side.

 

I didnt say a thing about an oil filter. And I plainly stated that you could tell that the valve cover etc was on a different plane.

OEM components are NOT going to work, considering the chassis is hand built with a toyota pickup front clip. I'm not an idiot just asking from some simple advice as I'm starting from scratch here.

http://www.mindlissmetal.com/1968-datsun/

 

Generally I would have just taken the measurements before I pulled it apart however I didnt want to trust the scrap angle iron mounts the truck came with to be correct.

 

Anyways thanks for the help. Basically just wondering what the best reference is. If someone knows the angle of the pulley centerlines, then thats all I need.

[72240z]

 

Generally I would have just taken the measurements before I pulled it apart however I didnt want to trust the scrap angle iron mounts the truck came with to be correct.

 

 

You would have had a reference though at least.

[datzenmike]

the L series engines are 'slant'-type engines and lean to the drivers side.

 

All Ls that I have seen are leaning to the right. (passenger side) In fact the right tilt from a vertical line to the center line of the cylinders is 12 degrees. Plus or minus a few degrees of lean won't affect drive line angle anyway, so not critical. The engine/trans center line must be aligned with the differential pinion center line when viewed from above or below. Because the diff moves up and down this only leaves the two drive line angles. These should be set with vehicle fully ready to run on a level surface with the driver seated in the cab. Changing the pinion angle will also affect the tranny angle slightly. Shimming the tranny mount up or down will also affect the pinion angle slightly.

[INDY510]

How would it affect the drive shaft if I raised the rear differential 2 inches in my 510?

 

I could use 620 motor mounts to raise the engine ~1 inch

 

And put a "shim" on the transmission mount...

 

Some Hacking may be involved.............. , but this is a hypothetical question.

[datzenmike]

If it just moves vertically up or down, the angle at the tranny and the pinion change the same amount so it shouldn't matter much.

[MindlissMetalfab]

You would have had a reference though at least.

 

It was visibly off kilter in every way possible. Not really worth a reference.

 

Anyways I talked to another guy who's set up a motor in these trucks with a toyota front clip. He used the top 2 bellhousing bolts to level it side to side so that's what I will do.

[RoadRace]

what you said was " since the valve cover, oil cap and oil filler all seem to be on different planes..."

 

for some reason you mentioned the oil cap and oil fiLLer as 2 seperate items so naturally i would respect that you have tried to identify multiple reference planes in an effort to get true positon for your install and the oil filTer would be a perpendicular plane, i did not read what you had wrote clearly. All reference points you mentioned above were not acceptable and i spoke to them as such. In fact they are all part of the same cam cover and will be, by definition included on the same single plane.

 

if you wanted to make sure what you have is correct, look at the oil pan from the front, you can see the total angle of inclination using the bottom of the pan sump as a reference point. The oil must stay level in the sump, so the pan rail has been raised on one side to compensate. running a straight edge off the pan rail with the bottom of the pan as 'level' will give you an idea of where you need to be.

 

my advice was to simply not try and re-invent the wheel. i would still locate an OEM Datsun crossmember and motor mounts and make them work in your toyota chassis rather than trying to fit a square peg into a round hole: make the toyota fit the datsun.

 

good luck and let us know how it turns out!

[MindlissMetalfab]

Sorry, my post meant to say oil cap and oil pan. Not sure why I put filler.

 

I talked to Seth at twisted minis and used the same method he used to set up the motor on this truck since its got the same front clip.

http://www.hotrodders.com/journal_photos/00044506/12570320470.jpg

Using stock datsun stuff wouldnt be much help. I'd have to modify it all anyways since the motor is lowered and the exhaust needs to pass through the crossmember. Plus I think mine's nicer.

 

 

I'm pretty happy with it so far. I may move the mounts on the frame back a 1/2" or so since its a little tight with my steering and I'd rather not have any issues. But I have to rebuild the engine crossmember to do that. So its later on the list, priority now is the floor so I can free up my chassis table for a customer.

[Unclejesse88]

Your crossmember does look nicer. As for engine tilt side to side, I always just figured the L engines were level when the carb flange was level