rearend of my 73 coupe got higher !

[JBQuick]

All, my mechanic/friend just finished an engine swap on my 73 coupe from a stock 2.4 MFI T motor to a 2.7 with Webers motor. To my surprise, the rear of the car sits higher now than when I took it there for the engine swap. I know he did not touch anything on the suspension BUT what do you think caused the rear of the car to go higher. I already drove it more than 30 miles but rear still sits too high ( approx 1.5 inches @ least )

What to do now ?

[rick2]

My guess is the MFI pump. Heavy buggars! Plus the fact he probably used a lift so the unsprung car will need to settle.

[JBQuick]

Thanks Rick, someone guessed the MFI pump as well, but I already drove the car for 30 miles, should'nt the height go back to normal by then ?

Thanks !

[bobmagyar]

You checked the dipstick right.

[RSupdate]

Thanks Rick, someone guessed the MFI pump as well, but I already drove the car for 30 miles, should'nt the height go back to normal by then ?

Thanks !

Your car will return to it's normal ride height after driving just a mile or two. It's all about the the cars weight on the t-bars....if the ride height has not been adjusted, the sprung weight of the car has chg'd. In your case it appears your new engine is lighter.

[JBQuick]

Thank you all for your input !

[RickS]

The 2.7s are notoriously lighter due to their helium filled valves. Hold on a second....... What dear? Oh, my wife says they are sodium filled and to foreget the whole thing. Never mind.

[pu911rsr]

The MFI stuff weighs about 60 lbs, carbs are very light. I don't know the spring rate of stock torsion bars off the top of my head but 1 1/2 inches sounds like way to much for 60 lbs. You could throw 50-60 lbs on weight on rear of car and see if rear end settles to where it was.
Phil

[chris_seven]

Effective rear wheel rate should be about 120 lbs/in with 23/24 mm dia rear bars.

If you add 60 lb weight to the car with a 40/60 front weight distribution then 36 lbs goes to the rear and each wheel obviously sees 18 lbs.

The wheel position should change by about 0.15"

If you have a ride heignt change of 1.5" then you have lightened the car by around 360 lbs.

Sounds good if its real.

Some one must have adjusted it this is the only realistic explanation.

( Occam's Razor must apply - All things being equal, the simplest solution tends to be the best one)

[berettafan]

Chris i'm not sure if your 60/40 explanation makes total sense. If you are putting 60lbs BEHIND the rear wheels that would be a different scenario. Seems like all of the weight would be going on the rear end. Might even take weight OFF the front?

Am i thinking wrong on this?