Help!! 85 hotair Rviera block with 2004r??

[WE287GN]

i just called GM and the flywheels for the two diff makes(87 lc2)in regal

and the 85 riv hot air block in a riv, 2 diff part numbers


so my question is

can i relax assuming the diff flywheel for diff tranny


or is this block not going to work mated with the 2004r

i had it in there already, but when pulled apart to do tranny and headgaskets

my flexpalte was very slightly wok -shaped in the area of the TC bolts

i thought first maybe i bent it by tightening when the converter had an ubstruction ,but i checked out and thopught to be good until i pulled it just recently

i am starting to worry that the tranny side of the blocks are different


any help would be gratly appreciated

Chris Pacheco

 

[GNVAIR]

The flexplates are basically the same regardless of whether the car in question had a TH200c (metric 3 speed), 3254L (fwd ala Riv, Toro, Eldo) or TH2004r
The difference is in the balancing.
The NA motors have no weight added.
The 84-85 turbo motors have some weight added (heavier pistons)
The 86-87 turbo motors have another (even heavier pistons)
You can tell the difference on some of the earlier flexplates since the ones originally used in turbo applications had the words "TURBO" stamped into them. The later ones and the replacement ones GM stocks now do not.
By looking at them, you will find the turbo ones will have extra small holes drilled OR a rivet or 2 added to balance the engine.
You have nothing to worry about. If you have a turbo Riv engine, you can use that flexplate with a TH2004r with no problems.

 

[WE287GN]

Originally posted by GNVAIR
The flexplates are basically the same regardless of whether the car in question had a TH200c (metric 3 speed), 3254L (fwd ala Riv, Toro, Eldo) or TH2004r
The difference is in the balancing.
The NA motors have no weight added.
The 84-85 turbo motors have some weight added (heavier pistons)
The 86-87 turbo motors have another (even heavier pistons)
You can tell the difference on some of the earlier flexplates since the ones originally used in turbo applications had the words "TURBO" stamped into them. The later ones and the replacement ones GM stocks now do not.
By looking at them, you will find the turbo ones will have extra small holes drilled OR a rivet or 2 added to balance the engine.
You have nothing to worry about. If you have a turbo Riv engine, you can use that flexplate with a TH2004r with no problems.

Hi Lee, thanks for the info.

so since i am using the 85 riv block with (wich i believe to be) stock turbo riv pistons,they have the reinforcements.

should i just try to locate a flexplate from a 84-85 tr ???

this was cool info , i didnt realise the diff in flexplates between the diff pistons in the engine

so i can throw away my worries on the distance from converter to back of riv block out the window????


thanks a bunch
Chris Pacheco

 

[GNVAIR]

To be honest, pretty much any 3.8 flex plate will do. I was just describing why GM has different part numbers for them. The 85 Riv flexplate should work if it isnt damaged.