Guys, I have 3.73s in my car right now and am thinking about upgrading to the 4.10s but am worried about being to high in the rpm range on the highway. I do not go all that fast and rarely over 85, but still do not want to be cruising around at 3k rpm at 70 for a prolonged period of time and do damage to my engine. My buddies here are honda techs who all own fox bodies. What are your experiences with them. I know there have been write ups on it but I want ur personal experience on this one area of it.
To the guys with 4.10s
- Thread starter cobrarob2345
- Start date
I have 4.10's in my car and at 70mph in 5th gear it turns 2600 rpm well below 3000 rpm as is your concern. With the stock 3.27's at 70 mph it turned 2200 rpm so as you can see there is really nothing to be worried about, 400 rpm difference is a moot point, you're not going to ruin your engine. Even if you had higher gears ...numerically...you still would not cause any damage to the engine at higher revs, that would be the least of my concerns.
+1, this is what I see. Where I used to run around in 4th on the interstate in town, I now do in 5th with the 4.10s. No big deal, and the kick in the pants from the lower gears is well worth it!
I would not worry about hurting your engine. If your exhaust is loud, it will be annoying cruising at just 55. Unless you are making a lot of extra power, you will really like the 4.10s, I like how you can actually accelerate to pass in overdrive a little w/o downshifting. The 4.10s are great, just a little louder and you need a speed cal or something else special to get the speedometer correct.
I have a Vortech and 4.10. They complement each other well. The b heads just don't have the bottom end torque. I would consider even more gear if I was naturally aspirated. Honestly not sure you will feel much difference if you are switching from 3.73. I would use the money towards something else. Save for the blower!
no im going na all the way till I enough save to do that and the t56 and forge the internals. Anyone her rocking 4.30s?
*here anyone go from 3.73's to 4.10s?
I do a lot of highway. Like 80%. Of my driving. I usuLy cruise at 70 @2600rpm. It's not bad at all.
do you guys think ill notice a difference between the 3.73 and the 4.10s
I have 3.73's and at 70mph I'm turning 2200 rpms with a T56 just to give you an idea of where you'll be with the 6 speed before 4.10s.
I did in my last Mustang and missed my 3.73's, but I do a fair amount of highway driving. mine is a DD so in this car now, when I switched, I went with the 3.73's again. most on here prefer the 4.10's, but not for me.
4.10 gears = 80 mph @ 2900 rpms
If you're not racing none of this means squat! stay with the 3.73 if there is nothing wrong with it. Meaning if it is quiet and no whine. If money is no object go with the 4.10. if thats what you want. it sure will not hurt. I have had all the gears. the 4.56 is best for acceleration, the 4.30 is good too. The 4.10 is kind of ok but hey when you had 4.56's it just seems lame. 3.73's not even in the same country.
If you're cool with a max speed on the highway of 80 cruising then the 4.10 could be for you.
If you're not racing none of this means squat! stay with the 3.73 if there is nothing wrong with it. Meaning if it is quiet and no whine. If money is no object go with the 4.10. if thats what you want. it sure will not hurt. I have had all the gears. the 4.56 is best for acceleration, the 4.30 is good too. The 4.10 is kind of ok but hey when you had 4.56's it just seems lame. 3.73's not even in the same country.
If you're cool with a max speed on the highway of 80 cruising then the 4.10 could be for you.
Skip the 4.10s and go to 4.30s.
Don't look back.
Don't look back.
I've had 4.30's and 3.73's now. I didn't like how high the rpms were on the highway with the 4.30's when going 80 - 90 lol. They put me at 3000 rpms at 75, which was ok. I can go 80 - 90 now without worrying about my rpms staying up too high with the 3.73's.. but they really just aren't as fun. I may switch to 4.10's to be honest. I think it would be worth the swap.
4.56s. At 80 it's above 3k but it's the only gear that just flat out works. I'll never swap them out. Even when I boost it.
4.10's are not bad at all. I wouldnt run any less. I think they are an all around good balance between 3.73 and 4.56.
I have 4.10's and churn about 2800-3k to keep up with traffic. I have the 99+ T45 and the DM kit isn't working (surprise) so I don't know how fast, probably 75 ish. I think it depends on your setup. With a KB or turbo I would go with 3.73's or lower, with Vortech or NA I'd go at least 4.10's.
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keep the gears you have. Not worth getting any higher unless your doing 1/4 mile runs every week.
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