Engine swap problem 2.8 to 3.4

[Martin]

Hi!
I came from austria in europe and i´m new here.
i have an 87er Firebird automatic transmission with 2.8 engine.
Now i have found a 3.4lt from a 94er Firebird with manual transmission.

We have swap the engine, gave all new, and now the engine runs ok,
but the hole chassis is vibration.

I use the 2.8 Balancer and the 2.8 Flexplate.

Also i use the 3.4 oil filter housing.
in the 2.8 oil filter housings are 2 sensors.
in the 3.4 only one.

i read in this forum the water pump must turn from the 2.8?
i don´t know but we use the water bump form the 3.4.
Is this a problem???

sorry for my bad english.
please help me, because in my country nobody have done this, and nobody can help me.

thanks alot
Martin

[bszopi]

Not 100% positive, but you probably need to get a 3.4 flexplate. I think the 87 2.8 is an externally balanced engine, whereas the 3.4 is internally balanced. Therefore, there are probably weights on the 2.8 flexplate that are causing an out-of-balance situation and therefore causing the chassis vibration.

And welcome!

[geoffinbc]

Agreed. Some 87's were internal balance and some were not. You need an 88 or later flexplate. Or your can remove the factory weight and have a machine shop neutral balance the one you have. Don't run the engine any more until you fix it. You can use the harmonic balancer you have on there.

[Martin]

Hi!

Thanks alot for your help.

Today i ordered a 3.4 Flywheel.

But whats the different between the 3.4 oil filter housing and the 2.8 oil filter housing.

Now we have mounted the 2.8l oil filter housing. is this correct?

Also i have the 3.4lt water pump. Is this also correct?

thanks alot
for your help.
Martin

[geoffinbc]

There is no issue. You can use any filter adapter you want. Usually you use the one that matches the car you are installing the motor to.

Use the 3.4L water pump only if you are running electric rad fans. The 3.4L pump has a shorter snout and will not accept an engine driven cooling fan.