[moxon4]

i have 3.42 gear ratio on a vortec v-6 95' cpi engine. my new wheels are 2 inches smaller than stock . will this help or hurt my acceleration and top end? what are the advantages and disadvantages of running 2 inches smaller than stock wheels on 3.42 gears? thanks to anyone that can help!

 

[98 SS ON NOS]

the 342 ratio is the true ration with trucks that came with 205 75 15 tires. which is a 27.1 inch tall tire it is a true 342 gear ratio. now with the 235 60 15 the ss model has its close to a 3.55 rear end gear. now you said the tires were 2 inches shorter than the stock tires so you are at 25 inch tall tire about *what is the sizie of a new tire if i know this ill be more exact"

so with a 25 inch tall tire your at a 3.70 rear end gear.

benefits is that you will take off fatster but lose a little top end speed. your rpms at 65 will go up about 2-300 rpms.

 

[01ZQ8]

I hear a lot of people talking about losing top end with higher gear ratios and that running at 80 I should be at some hella RPM. I have the 3.73's from the factory and running at 80 MPH Im only at about 2500 RPMs... Not that you are wrong Tony, cause I really have no idea...Im just stating my experience

 

[rick]

Will that not affect

the readings on the speed sensor???

 

[964pt3]

Top end does suffer, but if you had a top speed of say 130, after the tire change it would be around 117. And when do you actually get or need to go that fast? In a 1/4 if you get to 105 with these trucks youve done something, 110 is more than enough. As for the speed sensors they can take and error of 15% with no trouble max. Smaller tires with and auto is not a good thing unless youve gone though the trouble of having the thing recalibrated , and at 2 inches, your on the edge.Ive known people that have gone smaller in dia, smaller than you did, and blown the tranny because they didnt get it recalibrated.

 

[98 SS ON NOS]

lol i worked at a tire shop for a long time we put 205 50 15 on bagged trucks many times it was fine. ive never heard of anyone blowing the tranny out with smaller tires unless they are power braking it everywhere, they have high mileage, or tranny fluid was never changed. as for just the tranny going out when you put low pros on nah i dont think so. best thing to do is just smell or change the tranny fluid every 30000 on the 4l60es. the only thing that will be off is your speedo.

i have 275 35 18 which is 1.5 smaller than stock tire sizes, i was running 11 and 12s with my old motor tranny never got messed up, street raced on weeked on slicks that were about the same size tranny never blew up, blew the motor up put a stock one in on a 75 shot ran 13.3 on slicks, tranny never blew up, street race now on 18s and i abuse it like hell tranny still hasnt blown up. the only thing the lower profile tires will do is make your rpms go up about 2-300 on freeway with your set up. i had 410s and lost 600 rpms on freeway and my tranny was still fine, many others also went with 373 or 410 on this board the tranny is fine.

lol gettin the tranny recalibrated for smaller tires only has to do with the sending unit NOTHING INTERNAL. when people have speedo recalibrated with Hypergtech programmer it just messes with the speedo electronic sending unit, nothing inside changes

 

[964pt3]

LOL for people like you. Dont get it recalibrated and have the computer trying to figure out shift points and lock up times when your going too slow vs. the rpm. You can go up with gears and have no trouble, go down in tire size and cause all sorts of trouble. Too small and you will get premature tranny failure. 2 inches probably wont botherit, more will, but why take the chance.