1989 Chevy Caprice Help
FFTrey
02-03-2011, 09:47 AM
I have a 89 caprice with a stock 350 in it and stock 200r4 trans. I wanna do a cam, throttle body, and trans upgrade. Any suggestions
silicon212
02-03-2011, 07:24 PM
Double-check that engine you have. You can look at two places for the type of engine you have - on the RPO/SEO sticker under the decklid, it will have L03 or L05. If there's L05, then there's also going to be MD8 and 9C1. If there's L03, there's either MD8 or MW9, and there may or may not be 9C1 depending.
On the VIN, the 8th digit will be "E" for L03 or "7" for L05.
L03 is 305 cubic inch small block (VIN code "E"), L05 is 350 cubic inch small block (VIN code "7"), both TBI.
MD8 is TH700R4 trans, MW9 is TH2004R.
9C1 is SEO Police Package.
No 350s came in non-9C1 equipped vehicles from 1981 through 1992 due to CAFE regulations.
Once verified what engine you have, we can proceed.
Keep in mind with a cam swap, there are also other upgrades which have to be performed to work with the cam upgrade or the car could be an underpowered, fuelish dog.
If your car indeed does have the TH2004R trans, then you can upgrade this to a TH700R4 keeping in mind that you will need a driveshaft that's about 1" shorter to accomodate the nearly 1" increase in transmission length. All else, including the TH2004R TV cable should be reusable on the 700R4. One more thing to point out is that the TH2004R has its mount in the "TH400" location, while the TH700R4 has its mount about 3/4" behind the "TH350" mounting position. You should be able to use the TH2004R crossmember in the 700R4 position with some tweaking. If you can find one, there are 700R4 tailshaft housings that have a mount pad on them - this is in the '400' position and will allow you to retain the crossmember in its current state and location.
On the VIN, the 8th digit will be "E" for L03 or "7" for L05.
L03 is 305 cubic inch small block (VIN code "E"), L05 is 350 cubic inch small block (VIN code "7"), both TBI.
MD8 is TH700R4 trans, MW9 is TH2004R.
9C1 is SEO Police Package.
No 350s came in non-9C1 equipped vehicles from 1981 through 1992 due to CAFE regulations.
Once verified what engine you have, we can proceed.
Keep in mind with a cam swap, there are also other upgrades which have to be performed to work with the cam upgrade or the car could be an underpowered, fuelish dog.
If your car indeed does have the TH2004R trans, then you can upgrade this to a TH700R4 keeping in mind that you will need a driveshaft that's about 1" shorter to accomodate the nearly 1" increase in transmission length. All else, including the TH2004R TV cable should be reusable on the 700R4. One more thing to point out is that the TH2004R has its mount in the "TH400" location, while the TH700R4 has its mount about 3/4" behind the "TH350" mounting position. You should be able to use the TH2004R crossmember in the 700R4 position with some tweaking. If you can find one, there are 700R4 tailshaft housings that have a mount pad on them - this is in the '400' position and will allow you to retain the crossmember in its current state and location.
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