Ok, this is probably a stupid question. I am in the process of swapping an 88 5speed into my 87 gt. can I use the fly wheel from the 88? Have read that there is a difference(internally balanced vs external). Is this going to be an issue?
The 88 engine's rotating mass is balanced through the crankshaft and there were no weights on the back of the flywheel. Stock 87 engines were balanced via the flywheel as evidenced by flat pieces of metal welded to the back side of it. Using the wrong flywheel can generate vibrations that at the least can destroy bearings and seals and at the worst, cause the crankshaft to break.
You can identify an internally balanced crankshaft by the large reluctor wheel at about the center of its length. It won't have the notches cut into it, but it's the same flywheel as used in later DIS engines.
You will need an 87 flywheel for an 87 engine. Finding one in a parts store as they may not have the correct one. The shop that did my transmission work got the wrong one for my 87. A quick test drive after the install demonstrated that fact. The could not locate the correct flywheel. I was fortunate to have the shop find someone to reface the original flywheel and all was well. The shop was "upset" for they replaced the flywheel twice, dropping the cradle, exhaust, suspension twice.
Thank you for the replies. I had read a thread a while back about differences in the 88. I had forgotten about the flex plate/flywheel diff; I couldn't begin to say what made me remember but I'm glad I asked. I appreciate the advise.
That explanation clarifies a lot. Use an unbalanced flywheel on the 88 engine when it's installed into the 87 chassis. A common flywheel that's a bolt-in is the Beretta 2.8 or 3.1 V6 flywheel. It won't have any weights on the back side. If the clutch and pressure plate has any mileage on it at all, just go ahead and order a clutch kit for an 87 or 88 V6. It will have the correct throwout bearing. For fail-safe operation, put the extra money into good quality Rodney Dickman clutch master and slave cylinders for the Getrag trans. Then enjoy for many years to come.
Yeah - because he's given up finding the 87 flywheel to use with his LOWER MILEAGE 87 V6 engine.
That makes sense. I didn't read it that way, but you're right. It would be much easier to swap in an '87 flywheel onto his engine and hook up the trans and other things. He'd still need to swap out the engine harness from the 88.
BTW, KY87, you will need to replace the right drive axle when installing the manual trans. The automatic axle is shorter than the manual axle. And have you tried the Mall to see if anyone has one for sale?
Yeah - because he's given up finding the 87 flywheel to use with his LOWER MILEAGE 87 V6 engine.
I have an 88 formula (5spd)that will take some time to get fixed up and a 87 gt (auto)that is in really good shape. I want the 5spd in th gt for fuel economy. I will be starting school next month and would like better mpg. I have already pulled the cradle from the formula. And lack maybe 2hrs on the gt. I plan on swapping between both cars. If I don't swap engine and trans then I have to buy 87flexplate and an 88 flywheel for both swaps.