How to make sure the engine is perfectly straight?

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Nov 9, 2019 | 06:09 PM

TXjeepTJ

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From: Houston

How to make sure the engine is perfectly straight?

Doing an LS2 swap on a 1972 Camaro.

I read that on these Camaros, they engine is actually offset to one side of the car? Is that true? If so, awesome, as my next question is going to be difficult to answer..

I am using Dirty Dingo adjustable mounts. I got the engine/transmission in, with the mounts bolted loosely. I got the engine/transmission where I want it, but now how do I make sure the engine is straight? - is there a technique to make sure the drive-line is 100% straight?

Thanks!

Nov 9, 2019 | 09:31 PM

LS BRAVADA

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From: indiana

Maybe take a string and run it down the center of the car

Nov 9, 2019 | 11:03 PM

G Atsma

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From: Central Cal.

Lay a straightedge across the crank pulley. If it's parallel to the radiator you're good.

Nov 9, 2019 | 11:14 PM

QwkTrip

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You could drop a plumbob from the centerline of the damper. Then take another piece of string and tape it to the floor under the plumbob and run the other end to the axle pinion. Either eyeball the position of transmission tail shaft, or drop another plumbob from the transmission.

Nov 10, 2019 | 02:35 AM

LLLosingit

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From: Iowa

Just so you know, The engine doesn't have to be 100% straight, up to 3 degree's offset is fine. Sometimes the offset (to the passenger side) is needed to clear the steering shaft. The way I do it is to set the car/truck suspension up on jack stands, Measure the front side to side to find the middle then use a plum bob to mark the center line on the floor, Do the same thing at the rear. Then I use a chalk line to snap my line front to back. Then tape the plumb bob off the top of the balancer using the balancer bolt to center it up. Then use tail shaft of the transmission to line up the rear. If you don't already have a couple plumb bobs you can drill a hole thru one end of a long bolt and use a grinder to make a point on the end. Tie the string to the bolt with a big loop so that it doesn't screw up your results,

The reason you set the jack stands on the suspension is so that when you go to measure pinion angle the suspension is already in it's compressed state and not drooping.

Nov 10, 2019 | 05:53 PM

slogo

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I used a laser line, a craftsman from sears, put it in front on the ground under the radiator tilted it some with blocks. The laser line hit the crank bolt, the trans yolk
I had in to keep from leaking and the pinion nut all at the same time.

Nov 10, 2019 | 07:39 PM

Michael Yount

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Just to clarify -- TOTAL angles of 3 degrees are tolerated by most u-joints. Some cars have 2 piece drive shafts -- usually even more angle can be accommodated with that type of shaft. Since it's total degrees that the u-joints have to handle, the engine need not be perfectly parallel to the frame rails or perpendicular to the pinion flange. However, if you do introduce some angle because of engine alignment, this angle will reduce the vertical angle that you can have. So the old rule of thumb - engine/tranny 3 degrees down (high in front/low in back) applies only if you place the engine/tranny right in front of and on a line with the pinion shaft.

All of that to say -- you need to figure your engine placement with an eye towards the total angle the u-joints have to handle.