Forum Discussion
JetAonly
Feb 07, 2016Explorer
FWIW we have an 350 HP 8.3 in our Dynasty. We weigh 33k down the road. Without towed my 20k mpg was~8.3 with a 1500 Silverado 4x4 and 500 lb motorcycle in the bed over 10k mile we averaged 7.2. Plenty of HP with out towed. With towed it is adequate. Over Eisenhower tunnel at 11k ft we were about 30 mph. We are about 39k with towed.
The 8.3 was offered in versions to 380 HP from the factory. The transmission is the limiter on most of the 8.3 drive trains. We have the Allison 3066 which is rated to 350 HP and 1050 TQ. The ISL is an 8.3 block with a bigger stroke. It is also a fine engine. The ISL has some years with a bad wrist pin. There is a list of ESN's on this site.o
The 8.3 was offered in versions to 380 HP from the factory. The transmission is the limiter on most of the 8.3 drive trains. We have the Allison 3066 which is rated to 350 HP and 1050 TQ. The ISL is an 8.3 block with a bigger stroke. It is also a fine engine. The ISL has some years with a bad wrist pin. There is a list of ESN's on this site.o
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