355 gears. Or more ?

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A Body 440 WHY NOT

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Hello all.
I just ordered 355 gears for my 489 case sg. Car ( 69 Dart) will have a 440 , fat isky cam , alum heads, 10-1 comp. 727 trans , 2600 stall. My question is will that be enough gear for a street toy ? Or will it be dead off the red lights ? what 15" tire Can I find at 26 or 27" ? The 235s I see are around 28" tall and that may be working against me. Any input would be helpful.
Thanks
 
warm 440 in a Dart and your asking about a dead spot? IDK if there will be any dead spot. With that stall and RB power, youll puff those tires unless they are street slicks.
 
Mickey Thompson ET streets would help get the power to the ground...
 
will have a 440 , fat isky cam , alum heads, 10-1 comp. 727 trans , 2600 stall.
with aluminum heads and a very late closing intake valve, you have an opportunity to pump the pressure waaay up. So when you say "will have", then if you have not yet ordered the pistons, you could explore 11/1 or more, depending on how fat that cam actually is..
 
235/60-15 or 245/60-15 will get you in the 26"- 27" tire size.
355 is a pretty good all around gear. Go any taller and freeway driving starts to suffer. I think you will like it.
 
3.55 is good. I had 3.23s in my duster with my 413 and it was fine but now have 3.73s and it's nice. That 440 will blaze the tires with ease.
 
Which Isky cam, what brand of heads, and what intake are you going to be using? Unless it's a bone stock 8:1 motor home engine with a 300 plus degree cam, there definitely isn't going to be much of "dead spot" ROFL! That's the kind of car that should be capable of breaking traction at highway speed when the kick down is activated.
 
Which Isky cam, what brand of heads, and what intake are you going to be using? Unless it's a bone stock 8:1 motor home engine with a 300 plus degree cam, there definitely isn't going to be much of "dead spot" ROFL! That's the kind of car that should be capable of breaking traction at highway speed when the kick down is activated.
Engine masters 440 made 476 lb-ft with 7.4.1. So i im not sure you kill that much torque with a 440.
 
We've run 3.23s behind the 440 with an 18-spline four speed and been very happy with it. Ran 3.55s behind my son's warm 383 and 23-spline four speed. Was very happy with that, too. The 3.55s are in my Barracuda now (440/727). Might wind up being more gear than I really want for a highway cruiser. My son and I were talking about the 440/4sp car and overdrive or gear swap. We might try some 2.94s or 2.76s for highway cruising. The only "race" car of the bunch was the 383 car and it was more auto cross and handling stuff. I might have my Barracuda running later this month, but not on the road for a couple more months, at least.
 
what 15" tire Can I find at 26 or 27" ?

I have 245/60x15 on the back of my Valiant, they are 26.5" tall. I believe you can go up one size in your Dart, to a 255/60x15 with no issues. With the right rims and backspace, I think you can get one more size to 275/60x15.

Show us some pictures! I am in the hunt for a 69 Dart myself, just can't seem to find a good one.
 
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Hello all.
I just ordered 355 gears for my 489 case sg. Car ( 69 Dart) will have a 440 , fat isky cam , alum heads, 10-1 comp. 727 trans , 2600 stall. My question is will that be enough gear for a street toy ? Or will it be dead off the red lights ? what 15" tire Can I find at 26 or 27" ? The 235s I see are around 28" tall and that may be working against me. Any input would be helpful.
Thanks
A 245 or 255 wide tire on a 60/15 profile and wheel would be pretty good. check Summit Racing’s tire selection to get an idea of what brand of tire and there actual size as per the manufacturer of the tire says it is.

You may not be able to get a 27 inch tire on all brands. Some brands jump 2 inches at a time.
Happy Hunting!
 
General rule of thumb "used to be" 3.23 gears for big blocks and 3.55 or 3.73 gears for small blocks......but all these 700 HP small blocks (like LS motors) changed all that.
 
My 440 with 500 440 source kit , B&M holeshot Converter, 323 gear, TTI headers ,3" Exh. street car ran 11.7 1/4 mi. drove it there (about an hours drive) never opened the hood. I did have MT street slicks. They told me if I ran 11.5 or better I would have to cage it.

212.jpg
 
Hello all.
I just ordered 355 gears for my 489 case sg. Car ( 69 Dart) will have a 440 , fat isky cam , alum heads, 10-1 comp. 727 trans , 2600 stall. My question is will that be enough gear for a street toy ? Or will it be dead off the red lights ? what 15" tire Can I find at 26 or 27" ? The 235s I see are around 28" tall and that may be working against me. Any input would be helpful.
Thanks

Lets break this down a bit.

first off, 3.55 gears in a big block dart will be ok for strip use, fine for spirited street driving and highway friendly.

I don't know what a fat isky cam is, I'm assuming you have some lopey *** idle. Unless you can provide the cam specs that doesn't really help.

I can guarantee you with absolute certainty that your 2600 stall converter isn't enough for the combo and will be the detriment to your driving experience. I'd go as far as to bet it's an off the shelf piece that if you are lucky might perform like an inefficient stock converter.

As far as tires, you can get any height and width you want in 15". Go to summit racing and just keep narrowing the search criteria down. I.e. tires -- 15" wheel dia -- height ---- section width, etc. Once you find your tire, you can buy it from there or shop around.

A 235 tire height (in a 15") will be dependent on the 2nd number, i.e. 235/50R15.

Use an RPM calculator such as the one at RMS suspension to figure the tire height you require for your desired cruise speed. I base everything off 60MPH RPM because the highway is where you can quickly become most unhappy with a car. I.e. I run a 28" or 29" tall tire with my 4.56 gears to achieve 2500rpm @ 60mph. This may or may not work out at the strip but street performance and function should always outweigh strip function in a street/strip car because that's where it will live most of the time.

Last a 235 radial is useless on that setup. Get a real tire under it. My advice would be a 26x10.50 sportsman pro which with a offset shackle fits with ease and will hook it up. If you are dead set on radials go with a drag radial on the widest wheel you can fit. radials require the widest wheel per tire section width to function properly.
 
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Post #20 Good info there. Me I'm just a yahoo who I feel lucked out on my combo. I do like the 323 for highway cruise and it is still a bear from dead stop on the street. Tire in rear is a 235/50/R15 Street slick.
 
Lets break this down a bit.

first off, 3.55 gears in a big block dart will be ok for strip use, fine for spirited street driving and highway friendly.

I don't know what a fat isky cam is, I'm assuming you have some lopey *** idle. Unless you can provide the cam specs that doesn't really help.

I can guarantee you with absolute certainty that your 2600 stall converter isn't enough for the combo and will be the detriment to your driving experience. I'd go as far as to bet it's an off the shelf piece that if you are lucky might perform like an inefficient stock converter.

As far as tires, you can get any height and width you want in 15". Go to summit racing and just keep narrowing the search criteria down. I.e. tires -- 15" wheel dia -- height ---- section width, etc. Once you find your tire, you can buy it from there or shop around.

A 235 tire height (in a 15") will be dependent on the 2nd number, i.e. 235/50R15.

Use an RPM calculator such as the one at RMS suspension to figure the tire height you require for your desired cruise speed. I base everything off 60MPH RPM because the highway is where you can quickly become most unhappy with a car. I.e. I run a 28" or 29" tall tire with my 4.56 gears to achieve 2500rpm @ 60mph. This may or may not work out at the strip but street performance and function should always outweigh strip function in a street/strip car because that's where it will live most of the time.

Last a 235 radial is useless on that setup. Get a real tire under it. My advice would be a 26x10.50 sportsman pro which with a offset shackle fits with ease and will hook it up. If you are dead set on radials go with a drag radial on the widest wheel you can fit. radials require the widest wheel per tire section width to function properly.

Thanks for the info !
The isky cam has 530 lift and 248 degrees of duration at 050". Total duration is at 296.
Looks like I went " more is more " with the cam !
Should be a stout set up.
 
with aluminum heads and a very late closing intake valve, you have an opportunity to pump the pressure waaay up. So when you say "will have", then if you have not yet ordered the pistons, you could explore 11/1 or more, depending on how fat that cam actually is..

Thanks for the info ! Engine is together , on the stand. I do not know how to up load pics here.
 
I have 245/60x15 on the back of my Valiant, they are 26.5" tall. I believe you can go up one size in your Dart, to a 255/60x15 with no issues. With the right rims and backspace, I think you can get one more size to 275/60x15.

Show us some pictures! I am in the hunt for a 69 Dart myself, just can't seem to find a good one.

I fit some 255/60/15's in my 68 fastback. Gives me somewhere around 27".
 
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