They are different. F body bracket matched the shorter harmonic balancer hub. I'll see if i can find a dimension.
Lt1 in 78 malibu
- Thread starter Baker7888
- Start date
- Status
Here is some crank hub and accessory drive info from nook and transmission.
LT SERIES GEN II FRONT DRIVE CONFIGURATIONS | |||||||||||||||||
| |||||||||||||||||
| 
| ||||||||||||||||
There were basically 3 different front drive setups for the LT1 engines : Corvette, Camaro/Firebird and Impala. The Camaro/Firebird and Impala are very similar to each other. They are basically the same other than the main accessory bracket and power steering pump. The rest of the components are compatible with each other. Both of those setups had the accessories located on the passenger side. The Corvette had the accessories on the driver's side. The accessories and components are not interchangeable between Corvette and Camaro/Firebird/Impala. | |||||||||||||||||
| There are 4 different LT1 hubs. Basically, there are 2 hubs for each style balancer : Corvette & Camaro/Firebird/Impala. Then there are 2 hubs, depending whether the car is OBD I or OBD II. The OBD II hubs are .100" shorter than the OBD I hubs, since there is a sensor ring (crank position sensor) sandwiched between the hub and the crankshaft timing gear, and the shorter hub is to keep proper belt alignment on cars with that ring. All OE hubs are neutral balanced and can be installed in any clock position. None of the LT1 hubs are keyed. PLEASE NOTE : if you are converting a front drive from OBD I to OBD II or vice-versa (example : adding or removing the crankshaft sensor pickup ring), you MUST use the corresponding timing gear woodruff key with the matching hub, as they are different lengths. The OBD II keyway is longer, so it requires the longer key to hold the crankshaft sensor pickup ring in place, and then a shorter hub to keep proper belt alignment. | |||||||||||||||||
|
Great info here much appreciated. I did not consider the hub lengthHere is some crank hub and accessory drive info from nook and transmission.
There are 4 different LT1 hubs. Basically, there are 2 hubs for each style balancer : Corvette & Camaro/Firebird/Impala. Then there are 2 hubs, depending whether the car is OBD I or OBD II. The OBD II hubs are .100" shorter than the OBD I hubs, since there is a sensor ring (crank position sensor) sandwiched between the hub and the crankshaft timing gear, and the shorter hub is to keep proper belt alignment on cars with that ring. All OE hubs are neutral balanced and can be installed in any clock position. None of the LT1 hubs are keyed.
PLEASE NOTE : if you are converting a front drive from OBD I to OBD II or vice-versa (example : adding or removing the crankshaft sensor pickup ring), you MUST use the corresponding timing gear woodruff key with the matching hub, as they are different lengths. The OBD II keyway is longer, so it requires the longer key to hold the crankshaft sensor pickup ring in place, and then a shorter hub to keep proper belt alignment.
APPLICATION OVERALL LENGTH 92-95 Corvette, 93-95 Camaro/Firebird 3.519" 96 Corvette, 96-97 Camaro/Firebird 3.419" 94-95 Impala/Roadmaster/Caprice 4.09" 96 Impala/Roadmaster/Caprice 3.99"
Guys I have another question. I have a T10 supposedly from a 63 vette that I want to marry to my LT1. It is coarse spline. I do have the g body bell housing. My thought was to use a 63 vette clutch kit (coarse spline 10.5" - will fit in bellhousing) and a flywheel off 87 camaro (1 pc RMS 153T) When looking at the flywheel on the parts website, in the notes it says "26 spline" however I am assuming that is just a general note for the year/make/model and I am fine to use my coarse spline trans w it, correct? Also are all 1 pc RMS flywheel weights the same, or is LT1 a different size flywheel weight? (I started with 87 camaro cause I knew they were 153t and 1 pc RMS)
Great question. I believe the lt1 engine is internally balanced. The fly wheel needs to be neutral balanced.
Why not get a flywheel from a manual lt1 Fbody?
Why not get a flywheel from a manual lt1 Fbody?
Lt1 f body flywheel is larger so sill not fit in g body bell. It is my understanding LT1 is internally balanced but externally balanced at the flywheel. Thinking I can use the Camaro flywheel (153t) but just wanted to confirm. I need to use a 153t 1 pc main flywheel externally balanced flywheel so I can use the G body bell.
I dont think spline count of trans output shaft has anything to do with the flywheel but the "notes" make me feel like I should ask. (See pic)
Attachments
Last edited:
I don't suppose anyone has a PN for the OBDII keyway? A quick Google search produces nothing. Hadn't considered that with my impending OBDII swap. Or would a Vortec truck use the same thing?
Supposedly, the gm # for 96/97 is 12550096 List is $9 and change
Also, this link is good for general LT1 info (though they didn't give the late key #)
www.enginebuildermag.com
Also, this link is good for general LT1 info (though they didn't give the late key #)
LT1 Engine - Chevrolet Rebuilding
Although it shared many common dimensions, looked much the same and even had a few common parts, it was totally redesigned to provide more power with lower emissions and better fuel economy. Related Articles - Travel a New Road to AAPEX this Season - Randy Breaux, Group President, GPC North...
www.enginebuildermag.com
Last edited:
Just wanted to correct myself, for anyone in the future who uses this thread for their build research. I read the info wrong and it turns out LT1 is infact a 153 tooth. Lots of misleading info online (regarding sbc flywheels) I bought both an LT1 flywheel and a Post-86 flywheel and they have the same bolt pattern and both are weighted but the LT1 is more of a "deep dish" on the engine side whereas the Gen I flywheel is flat. My motor is on the stand so I cant really determine why just yet but long story short, they are different. I believe also the LT1 pistons are lighter than the Gen I pistons therefore creating different balancing requirements. I was tempted to try and fit the Gen I piece as it is definitely lighter but I am going to play it safe and use the intended flywheel.
- Status
Similar threads
