Double Pumper with 3.55's

[MagnumForce]

I am considering getting 3.55's for my charger in order to be able to do more highway driving. My only concern is that the car will be a dog off the line because i am running a mild 340 with a 650 double pumper, a 727, 20 inch tall tires, 3000-3500 stall and i have 4.10's in the car now. Are the 3.55's going to be worth it or should i stick to 4.10's if i am looking for a street/strip car?

[Troy]

20 inch tires? I like 3.55 gears. Hate 4.10s. But I drive a LOT on the highway! With a stall that high you may still be ok with 3.55s (depends on your cruising speed). It wouldn't work for me. With 3.23 rear gears I'm turning right at 3,000 rpm at 72 mph. Engine wise I think you're fine.

For a street/strip car the 4.10s are the ticket - but you have to sacrifice anything more than about 55 mph on the highway. Only real option in that case is to get an overdrive.

Troy

[Ghoste]

Yeah, it comes down to how much of what type driving you do.  I love 4:10's but unlike Troy, I don't do a lot of highway driving.  I think with 20 inch tall tires though, you might find 3:55 to suit you just fine.

[Cooter]

Or........you could do like I and many in the club do, take your time with the 4.10's.

Troy, Ghoste, THIS would be a right lane ride on the Interstate. 

[Ghoste]

Trust me, if I'm on the interstate that's the lane I'm in.

[flyinlow]

Or ... you could put an A 518 transmission behind the that small block and make your overall top gear ratio 2.83, hit the LEFT lane of the freeway and have fun..fun..fun  'till  Obama takes your Charger away.  

20 Inch tall tires?  

[Cooter]

A 518 in a street/ strip car?
Not likely for long.

[c00nhunterjoe]

20" tall??? What size are they? Even the g60 14's are still 24" if i recall.

[MagnumForce]

They are Dunlop G/T Qualifiers, actually they may even be a little smaller than 20. Its been a while since i checked the hieght. My biggest concern is if the double pumper and the 3.55's are going make the car a dog off the line. I now it is not going to be anywhere near my 4.10's but the closet track to my house is Lebanon Valley which is a good 1 1/2 hours away and 55 in the right lane gets old fast

[Cooter]

Put it on a trailer. That driving it to the track sounds like billy badass stuff......until your stuff breaks.
ask me how I know.....

[firefighter3931]

They are Dunlop G/T Qualifiers, actually they may even be a little smaller than 20. Its been a while since i checked the hieght. My biggest concern is if the double pumper and the 3.55's are going make the car a dog off the line. I now it is not going to be anywhere near my 4.10's but the closet track to my house is Lebanon Valley which is a good 1 1/2 hours away and 55 in the right lane gets old fast

I seriously doubt your tires are 20 in tall....more like 24 or taller.  

That being said, a double pump carb won't make a car sluggish off the line unless it is improperly sized and not adjusted properly. A 650dp is fine for a 340 and definitely not too big.  


Ron

[MagnumForce]

Thanks for the advice guys, i think im going to go with the 3.55's for the best compromise 

[Troy]

Or........you could do like I and many in the club do, take your time with the 4.10's.

Troy, Ghoste, THIS would be a right lane ride on the Interstate. 

You bet! Add a droning muffler and it's like my idea of hell on earth.

The ONE time I did it the air temp was 96+ degrees with 80+ percent humidity. I was in a Challenger (very little air flow even with the vents open and windows down) with a black vinyl interior. I got passed by a Smart car! To top it off there was a big cloudburst/thunderstorm late in the day and everything fogged up about the time the car got real squirreley. Good times!

Troy

[Troy]

I'm going to guess the tires are taller - which is why I asked. Stock tires are about 26" tall. Most people with after market wheels and wide tires end up with about 28" in the rear. This lowers the "effective" ratio of the rear axle gears. Obviously smaller tires will raise the effective ratio! With 28" tires your 4.10 is acting like a 3.91 and a 3.55 will act like a 3.23. With 20" tires your 4.10 would act like something well above a 5.00 I believe. Literally you'd be turning 4,500 rpm or more at 55 mph. It would also look like one of those wire wheeled lowriders!

Troy

[MagnumForce]

I finally got a chance to measure the tires and it was more like 28 inches. I have no idea where i got 20 from