78 k5 with turbo 350

[97sas'd]

Hey guy's my buddy want's to gear his blazer. He will be running some 37/13.50 toyo's on it and i know that with my 97 4.88 will be fine for some highway driving to silver lake. I also know the trans he has is 3 speed auto, no OD. We are trying to figure out what the best gear would be for his Blazer. I'm thinking a 4.56 with 37's would do nicely but figured i would verify with the pro's before telling him to pull the trigger on a gear set. On that note what gear's are most of you running brand wise. He want's a good economically priced set. Personally i was planning Yukon's on my 97 but if there's something you recommend shoot. Thank's for your time.

 

[offshift]

I like to run the percentages. I am planning on running 41.5's on mine and they are about 32.5% larger then stock so I ran 32.5% lower gears. Stock tires about 28" new tires 41.5". Old gears 3.41 * 32.5% = 1.11 3.41 +1.11= 4.52 so I went with 4.88s to get a little more power and the option to go with bigger tires.

Mine is on a 91 with computer stuff on it so this should put my speedo back close to what it should be and make everything jive again computer wise. He should run the numbers and pick the closest gear on the low end if he might ever want to go with bigger tires or wants more pulling power or go with the higher if he will never go bigger and wants better gas mileage.

Hope this helps and isn't to late.