3.23 vs 3.55 8/34

[challengermaniac]

Would 3.23s really be a jump up from my 2.76s?  I just have so little low end right now.
[/quote]

Both the 3.23 & 3.55 will improve your low end (with a little lower gas mileage).  If you are happy to "squak" the tires, go with the 3.23, but if you insist on needing to "burn lots of rubber", go with the 3.55! 

The fresh rebuild on my 1970 340 is not completely broke in yet, so I have yet to really push it beyond squaking the tires, but the 3.23 suregrip is performing well.     

[Tonefiend]

I went from 3:23 to 3:55 and there wasn't a noticable difference.  Don't have a tach though.

[shadango]

Yeah, I have 2.76s and they are greatfor highway too.....

But what are the 3.23s, with a 318/340, like around town?  Will it buy me any low end?  They are so numerically close, I am wondering.

[BIGSHCLUNK]

I cant say much about the small block but NIKKI can get plently 0ff the line w 3.23's 

[shadango]

Yeah, you have gobs of low end i am sure....not so much here. 

Its a 318 thats cam'd and such and goes great up top.....

[HP2]

With a 318, I doubt you would have any problems even using a 741 case if you found one with the right combination at the right price.

If you find a cheap set up without a sure grip, it is not too tough to replace the carrier and have a sure grip.

What camshaft do you have in the engine now? That may help you decide the gear set more than you think as the torque curve the engine produces can have a big impact on how the car reacts to gears. It also impacts the mileage as simply spinning the engine slower does not necessarily improve the mileage, although lower rpm will help with engine longevity and road noise while cruising.

[shadango]

Well, its either a mopar or lunati (its purple) but no idea what grind it is.....

lumpy idle and low vac though

[SBDave]

This weekend I drove from Santa Barbara, CA up to Oakland, CA (340 miles) and with my new Truetrac 3.55, 26" tall tires, 904 trans, and a 318 with a mild cam and exhaust, it was a struggle. I was cruising in the slow lane around 65-70 which feels really slow out there on the road when people are driving 75-80.  Eventually I'll be switching to a manual transmission with an overdrive, but this combo right now isn't good for long distance freeway driving.  I think with 3.23's and some 28" tall tires I would have enough top end to not need OD with my setup.


Dave

[Road_Runner]

This weekend I drove from Santa Barbara, CA up to Oakland, CA (340 miles) and with my new Truetrac 3.55, 26" tall tires, 904 trans, and a 318 with a mild cam and exhaust, it was a struggle. I was cruising in the slow lane around 65-70 which feels really slow out there on the road when people are driving 75-80.  Eventually I'll be switching to a manual transmission with an overdrive, but this combo right now isn't good for long distance freeway driving.  I think with 3.23's and some 28" tall tires I would have enough top end to not need OD with my setup.

I'm very interested in your impressions as my Barracuda has the same engine/trans/rear combo you did before your swap to 3.55's.  Like Shadango, my cars a pig with no noticeable acceleration.  And at least right now, my plan is to stay with the Slapstik auto, so if there is a perfect compromise gear I'd love to figure out what it is without spending the $$$ trying several.  Do you have a tach and if so what was your RPM at 65-70.  I remember how I initially went slower after installing a lower gear in the Roadrunner because I wasn't used to hearing the RPM that high.  Once I got more used to the increased noise & vibration, I was cruising right along with everyone else.  I was thinking 3.55's might be that perfect ratio with a mild 318, but perhaps a 3.23 would be better.  I just need something to wake up the 318 or I'm definitely going with the 340 because this thing has just got to move better...

Later, Jim

[shadango]

Hey Road runner

Dont get me wrong.....my lil 318 does ok....its nota dog....just not the cheetah I want it to be...LOL...I know there is more, in other words.

Man, when I downshift to second or 1st for passing she wails and hauls butt pretty good.....

Its just that off the line its not stellar....figured the 2.76s were contributing to that...having lots of fun as-is, but you know how it is...LOL

Was considering a 741, but what the heck...might as well go for the gold and wait for the 742 combo I need, or buy from Dr Diff.

[Glennster]

 I went from a 3.23 to a 3.91, it's a great change for around town. I run 3,000 rpm's at 55 MPH with the 3.91...........
I think it depends on where and how you drive. I thought I needed the 3.23 for trips, heck, I never do long trips. I go to local cruise in's and mostly stay around town. I love the 3.91, the car is a BUNCH quicker!

[mopar12372]

manciniracing looks to have great prices for what ever you need
http://chucker54.stores.yahoo.net/comcen.html

[brads70]

Bummer I didn't know you were wanting to change gears! My spare is a 3:91 open ( no sure grip) I could have brought it down to Carlisle and let you use it till next year ( Carlisle)

[flyguyskt]

just bought a 73 cuda with a 440. he gearing is waaaay to focused on highway speeds but not sure what is in there. its an automatic and was originally a 318 car... what would be a good ratio? i was thinking the 3.55? for mostly town driving with some highway.

thanks everyone

[brads70]

just bought a 73 cuda with a 440. he gearing is waaaay to focused on highway speeds but not sure what is in there. its an automatic and was originally a 318 car... what would be a good ratio? i was thinking the 3.55? for mostly town driving with some highway.

thanks everyone

I have 3:55 with a 255/60/r-15 and a 440/727,  tire it's about 3000rpm's at 100KPH
( 62 MPH)
I like it!