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different tbi 350s

4K views 10 replies 0 participants last post by  mass9c1  
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#1 ·
were the regular caprice L05s different from 9c1 L05s? what about truck and van L05s?
 
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#6 ·
Just trucks kept the flat followers/tappets. Automobiles are rollers. For an L05, it all depends what it came out of.
Other differences are those mentioned, slightly bigger injectors and PCM adjustments, and 'bigger' cam are the ones I'm aware of. If I've missed something, I'm sure KRolt will tell us. ;)
 
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#7 ·
The L03 & L05 model motor was a hydraulic roller motor, unless it was in a truck.

The bigger Y-pipe was only on the 9C1 I might add.

Also the 9c1's had 65lb/hr injectors while the truck motors and regular L05's got the 55lb/hr, the L03 got the 45lb/hr. The only difference was the 454 of that same era as it got the 2" TBI and I believe 85lb/hr injectors.

The PCM tune was the same for all 91-93 TBI's, it only varied because of the type of injectors the motor had and the 9C1 "tune" had the speed limiter removed and also added the Wide Open Throttle A/C cut off. Also depending on the model Caprice the speedometer was set different to accomodate different sized "stock" tires.
 
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#9 ·
mass9c1 is correct. cars with TBI v8 (both 305 & 350) had roller hyd cams; trucks with TBI v8 got flat tappet hyd cam.

Only the 9C1 350 got the larger exh Ypipe; it also got the L98 cam, 65 lb/hr injectors and the revised calibration in the ECM to suit the cam + exhaust, so it got rated at 190, 195 or 205 fwhp (in 1989-90, 91, and 92-93 respectively). The civilian TBI 350 was always 180 fwhp.

Trucks, OTOH, got a lower-restriction louder exhaust and a cam that was not as large as the L98 cam, but it was also larger than the std 305 or civilian 350 cam... so they were rated at up to 210 fwhp in their last year in light trucks/vans (1995). Trucks usually had lower CR than the car engines, and that was done IIRC by having dished piston crowns. The heads should eb the same swirl port heads used on the cars. Trucks probably had 4 bolt mains but that doesn't help power at all.

There were also some slight differences in the truck TBI units, vs the ones used on cars, because some of the fleet-type light trucks had built-in speed govenors on them. I think there are example pix on the Thirdgen.org website. HTH.

EDIT: PaulD --- the Championship sod is doing nicely. Maybe there will be a 2nd installation in a month.
 
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#11 ·
as long as you get the motor for the correct year, i.e. the 91-93 cadillac B & D body L05 it should be alright, as the description could be a typo.

http://www.sdpc2000.com/catalog/123/products/105/1991-93-Chevrolet-Cadillac-B-D-L0557K.htm

if you're looking for a replacement engine why not look into this 383 as it's only $2k more and is a complete long block instead of just a $1700 short block.


All you need to do is purchase a new TBI vortec intake manifold if you didn't want to use an adapter plate, on the carb manifold.
Also the addition of a walbro 255 and necessary fuel system upgrades & you should be good.