Engine Level Question

I had my truck sitting at what I thought I wanted the ride height to be and set the engine level at the carb pad. Now that I have been able to remove the jack stands and play with heights again, I found that I like the truck sitting lower in the front than I did before, BUT, now the engine sits higher in the back and is no longer level. The question is, do I need to level it back out if I decide to keep the overall stance lower at the front wheels. The mounts are only tacked in, so its not a huge deal, but I would have to remake the tabs on the back of the motor plate, which took me some time to make in the first place.
The lazy side of me says that guys lower cars all the time and don't really check to see if the engine sits level, but the perfectionist side of me says to quit makin' excuses and do it. So...what do I do?
If you want to see some pics, you can check out my build thread in my sig.
Thanks in advance guys.
Eric

 

0 to 4 degrees is acceptable, but right around 0 to 1 is optimal.

 

Thanks Buzznut, I didn't check the angle finder. Probably would have been a good idea.

 

Doesn't the motor angle have to be set to some relation to the diff. angle? if so I'd keep that in mind when making any changes to the motor angle.
-Pat

 

Yes, which is why most carb bases are machined at an angle. The carb needs to be level, the motor doesn't.

 

Thanks for the input guys. With the front lowered, the pinion angle is within 3* of the trans. Also, I'm running double adjustable ladder bars, so I can adjust the pinion angle if need be.

 

X2.. the crankshaft centerline needs to be roughly at the same angle as the pinion gear shaft in the rear end, and one needs to be "higher" to get somewhere around 3 degrees on EACH U-joint, to keep grease moving in them.

So, if those are perfect now, changing the motor angle is not a great idea if it ends up being too much as far as mismatch on the U-joints.. Carb angled spacers are sometimes used, if needed.

 

Motor should to be level if your running a carb, injected it doesn't matter.

 

why is level important? there isn't a level road within a hundred miles from my house.

 

You are right that with the front down it will be OK. First off you set the frame at 0* then set engine down 4*, carb is level, and then pinion up 4*. That is the important setup. Then you can set the rake anywhere you like, even with a carb. I drove many cars with the front end lowered and the carb surface down at the front and it made no difference to the running of the engine.

 

What you started out to do is the correct procedure. Set the ride height, level the carb pad and set the pinion angle to match the centerline of the crankshaft/transmission centerline.

When you altered the chassis stance, as you noted, the carb angle was no longer level. If that's 1* or so, I wouldn't worry about it. But the further from level the carb pad, the less desirable that is.

Ideally, the carb should be level on a level surface at ride height.....because....it then can better tolerate angle changes resulting from normal driving up and down hills, driveways, etc. If it's starts off at an angle on level surface, the tilt is either improved, or exaggerated, depending on circumstances.

The carb float setting is based on level. Varying from level will change the fuel level in the float bowl with the corresponding affect on leaner or richer mixture. You could change the float level slightly to compensate for that, but it would be guess work.

Do cars quit running when going up/down hill? no, not usually, unless the angle is severe, as is often experienced with offroaders. But the fact is, there are subtle changes in mixture, whether immediately noticeable or not.

Do what ever you think will best satisfy your standards.

 

Set up chassis at desired height and rake then adjust engine transmission to 3 degrees down at rear. Set pinion at 3 degrees up to be in phase. Weld everything up. Once done you can then do whatever to chassis as angles are correct.