Cast date is G140 = July 14 1990, heads are ...193 swirlport TBI, 64 cc, 1.94/1.50, block is ...638 one piece rear seal TBI block, should have roller cam from box Chevy.
What's odd is 350 TBI was in trucks. 305 was in Caprice, unless police fleet vehicle. Yet all of the 350 Police I am aware of, were TPI (Tuned Port Injection) and not TBI. The 350 TPI was same engine in the ambulance units, brought over from the Corvette line. Later on in the "bubble" caprice were LT1. I drove several as an LEO.
Yours has manual FP which was added later. Many of the blocks of this era were machined for manual FP, yet installed the cover plate and with an electric in tank FP. The block most likely will have the cast bosses for the "spider" for the roller lifters. From 86 to 90 was a toss-up if it had roller cam.
Notice on the back of the block, you have the two Oil Pressure sensor/switches. One was for oil gauge on dash, the other (long narrow) unit is the switch to energize the in-tank FP once started.
Notice the accessories are multi V belt system with the AC on the drivers side. This is exactly the way it would have been in a Caprice. It is pre-1991 as the 91 Caprice had the serpentine belt setup. Although some 1990 Caprice had serpentine system.
Basically you have a 350 TBI, factory Dish, 8.6 to 8.8 CR respectively and about .230 lift cam 114 or about LSA. Change to flat tops, 230 to 240 @ .50 and .480 lift and 1 5/8 headers will be nice easy street engine about 9.2:1 and DRC about 7.5 which. Will keep detonation down with pump gas.
Anything more and it's going to max out about 3500 to 4000 with those heads. The block can be worked to 383 but definitely will need better heads.
What's odd is 350 TBI was in trucks. 305 was in Caprice, unless police fleet vehicle. Yet all of the 350 Police I am aware of, were TPI (Tuned Port Injection) and not TBI. The 350 TPI was same engine in the ambulance units, brought over from the Corvette line. Later on in the "bubble" caprice were LT1. I drove several as an LEO.
Yours has manual FP which was added later. Many of the blocks of this era were machined for manual FP, yet installed the cover plate and with an electric in tank FP. The block most likely will have the cast bosses for the "spider" for the roller lifters. From 86 to 90 was a toss-up if it had roller cam.
Notice on the back of the block, you have the two Oil Pressure sensor/switches. One was for oil gauge on dash, the other (long narrow) unit is the switch to energize the in-tank FP once started.
Notice the accessories are multi V belt system with the AC on the drivers side. This is exactly the way it would have been in a Caprice. It is pre-1991 as the 91 Caprice had the serpentine belt setup. Although some 1990 Caprice had serpentine system.
Basically you have a 350 TBI, factory Dish, 8.6 to 8.8 CR respectively and about .230 lift cam 114 or about LSA. Change to flat tops, 230 to 240 @ .50 and .480 lift and 1 5/8 headers will be nice easy street engine about 9.2:1 and DRC about 7.5 which. Will keep detonation down with pump gas.
Anything more and it's going to max out about 3500 to 4000 with those heads. The block can be worked to 383 but definitely will need better heads.
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