Street Gear Poll

Which street gear?

  • Total voters
    443
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toolmanmike said:
My calculator comes up with 115 mph. @ 5000 rpm. You should get your speedo checked. There's a reason why Ma Mopar used the 3.23 ratio in most of the performance cars they built. Because it's a great all around gear. Mopar engines are designed to produce a lot of torque and really don't need a lot of rpm to perform well or a big gear ratio.
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115 sounds about right for my Dart. I need a 38 tooth speedo gear, now that I've replaced the 2.45 rear with a 3.55. With the 2.45, I figured like 150-160 top end. Still not interested in breaking 100. My friends RR with 3.55's and 15" wheels can do 120. Nailed the Dart coming out of a corner the other night and it got crazy squirrely. Had to back off. What a difference going from 2.45 to 3.55. Saved the little copper tag with 2.45 stamped on it.
 
mguner said:
A Cheech & Chong song comes to mind when thinking of those 14" tires.....
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Speed rating? We doneed no steenkeng speeedrating. lol
I was 17, and invincible.
It mighta bin 88mph! IDK
Polyglass RWLs. Hard as rock when cold. Almost no change when hot. Squeal 'em for a city block;through two gears for sure, probably to 70 mph, or more. Nice looking tire, but junk for traction. 4-wheel slides around corners. wipe-outs when turning,leaving stopites; as in accidental 180s. slippery lane-changes. Yeah those tires were a handful.Fun after the learning, but not something I'd ever buy again. Junk compared to todays tires. 100% Predictable tho;guaranteed to be scary!
 
AJ/FormS said:
Speed rating? We doneed no steenkeng speeedrating. lol
I was 17, and invincible.
It mighta bin 88mph! IDK
Click to expand...

It's a wonder we are here to tell the story. Those tires weren't even radials. And mine were usually just skins.
 
Cool stories guys I love reading these...

You can see what I voted for from my sig. I'm also running 275/60-15's. I currently have 2.94s in there and it's actually not bad since my 360 has 10.5:1 compression and a small 213/220* @ .050" cam. I like driving my Duster on the highway and when I put in a 4.10-gear chunk to test out it made me hate driving it anywhere but the drag strip since I couldn't floor it off the line on the street without becoming a cop magnet. With the 2.94s, with 1" torsion bars up front it's really solid and planted at high speeds, 120 MPH isn't unstable in the slightest.

The engine really needs a bigger cam (pings a bit) and I have lying around a "mystery" 2500-stall converter which I tried before but thought the slippage was killing gas mileage (it wasn't). My plan is to get another 3rd member with 3.55s and sure-grip to use most of the time and keep the current one for when I want to go on the occasional long-distance road trip.

You didn't mention what kind of rear end you have, if it's an 8 3/4" having multiple 3rd members is the way to go. 2.94s for the highway, 3.91s for punch on the street or strip.
 
AJ/FormS said:
Speed rating? We doneed no steenkeng speeedrating. lol
I was 17, and invincible.
It mighta bin 88mph! IDK
Polyglass RWLs. Hard as rock when cold. Almost no change when hot. Squeal 'em for a city block;through two gears for sure, probably to 70 mph, or more. Nice looking tire, but junk for traction. 4-wheel slides around corners. wipe-outs when turning,leaving stopites; as in accidental 180s. slippery lane-changes. Yeah those tires were a handful.Fun after the learning, but not something I'd ever buy again. Junk compared to todays tires. 100% Predictable tho;guaranteed to be scary!
Click to expand...


Lolol, it's a wonder we survived the "good ole days".

Sometimes I think back at a few of the things I did and just cringe....
 
Cringe is right!
But you know what?those boys kept coming back for more. And I kept giving it to them. To me it was ordinary. Can you imagine the stories those guys are telling! My younger brother was along occasionally. His memories of terror are not at all the same as mine.
Multiple chunks is what I have accumulated; almost everything from 2.76s to 4.30s. plus a 5.13 and a couple of 4.89s.

MOPEkid
I did a little math on your set up. I assumed ramps totalling 45* for your cam, and ground on a 112CL. That makes your cam advertised at about; 258/266. If it was installed about straight up, that would put the intake closing angle at about 59*ABDC. And that would make a 10.5Scr chamber into a 8.72Dcr motor.
Now, if that's anywhere near accurate, yes 8.72 with iron heads is apt to"ping".
If it does so on Premium, then it would be prudent to make a change. However, if you care to; a change to your cam timing might be all you need if your case is borderline. Retarding your cam just 5*, might put The Dcr to 8.4, which might get you out of "ping",with Premium.
And bear in mind, the engine only needs enough octane to suppress detonation under it's maximum loaded condition. During putting around and hi-way cruising it might only require 87 octane or even less. A lot less. Furthermore if it's not "pinging at WOT, then slowing down the rate of advance so that the all-in timing is a couple of hundred rpm later, may get it out of trouble.
Another thing that can help is to kick the Vacuum advance out a little sooner. You know those cans are adjustable through the nipple, right?
And if the cam was installed at the typical 4* advanced, then giving up 5* of cam timing; you probably wont even notice.Except for the diminishement or elimination of the "ping".Yeah I know it's a PITA job, but it's easy and super cheap. And you get to keep most of that 360 torque.
Good luck.
 
AJ/FormS said:
Cringe is right!
But you know what?those boys kept coming back for more. And I kept giving it to them. To me it was ordinary. Can you imagine the stories those guys are telling! My younger brother was along occasionally. His memories of terror are not at all the same as mine.
Multiple chunks is what I have accumulated; almost everything from 2.76s to 4.30s. plus a 5.13 and a couple of 4.89s.

MOPEkid
I did a little math on your set up. I assumed ramps totalling 45* for your cam, and ground on a 112CL. That makes your cam advertised at about; 258/266. If it was installed about straight up, that would put the intake closing angle at about 59*ABDC. And that would make a 10.5Scr chamber into a 8.72Dcr motor.
Now, if that's anywhere near accurate, yes 8.72 with iron heads is apt to"ping".
If it does so on Premium, then it would be prudent to make a change. However, if you care to; a change to your cam timing might be all you need if your case is borderline. Retarding your cam just 5*, might put The Dcr to 8.4, which might get you out of "ping",with Premium.
And bear in mind, the engine only needs enough octane to suppress detonation under it's maximum loaded condition. During putting around and hi-way cruising it might only require 87 octane or even less. A lot less. Furthermore if it's not "pinging at WOT, then slowing down the rate of advance so that the all-in timing is a couple of hundred rpm later, may get it out of trouble.
Another thing that can help is to kick the Vacuum advance out a little sooner. You know those cans are adjustable through the nipple, right?
And if the cam was installed at the typical 4* advanced, then giving up 5* of cam timing; you probably wont even notice.Except for the diminishement or elimination of the "ping".Yeah I know it's a PITA job, but it's easy and super cheap. Good luck.
Click to expand...

Thanks AJ, attempting not to hijack the thread... my current cam is the Voodoo 256/262 so your calcs are pretty close. You are right about the pinging it only does it when I'm on it really hard in the daytime if it's sunny out. Heck even just adding a proper sealed cold-air intake/hood scoop for the carb would probably fix it. But yes I can putt around running 87 (mid-grade here) with no issues. HOWEVER the thing that scared me, my last couple oil changes I've seen a bit of fine metal flakes in the oil which I've read is usually bearing material caused by knocking which hammers the bearings badly. I want a bigger cam anyway to move the power band up it likes to be shifted just over 5000 RPM, could use more top-end for sure. I will play with the vacuum advance, this engine pulls a lot of vacuum and when I give it throttle the max amount on just the primaries it's still pulling like 7-9" on my gauge even from a stop.
 
Let's play a bit. I rehashed the numbers, and if your cam is on 112 and installed at 112, then the ICA is 60* so we're right on the money with a Dcr of 8.64.
Now the next bigger cam is about 262 intake and if ground on a 110, and installed at 110, then the ICA is 61*, so that helps you nothing.
Going to the popular 268* cam; also a 110 and installed at 110, then the ICA comes to 64*, making the Dcr 8.40. Probably not a significant enough change. And if you advance it 4* to the popular install of 106 centerline, that drops the ICA back to 60*, and you're back in the same Dcr of 8.64. So even though you are moving the power up some 600rpm,( give or take), it's not helping you're "ping" one bit.
You may only have three options;
1) reduce your Scr a bit
2) delay or reduce your timing
3) get a much bigger cam, or a custom cam, or run the cam retarded some.
4) get the charge temperature down.
I know I know, that's not three, it's four.
So here's a possible cam; the 268/276, ground on a 114CL installed at 112*. This works out to a Dcr of 8.27. That should do it. That will move the peak power up some 500 to 600 rpm, giving you a bit more power, and,the powerband will be a bit wider, and you may be shifting it around 6200 or more. So springs will be needed.
But heres the thing; you will need some good heads to realize the cam gains.Otherwise you'll just be spending money to "de-ping" your engine, which you can do by retarding the current cam. Oh boy!
 
AJ I would go with the 268/276 in a heartbeat but with 1.6 rockers and unmachined guides on stock Magnum heads it has too much lift (well over the ~.525" max with the Hughes retainers I have) and risks retainer-to-guide contact. By suggestion from RRR and Abodybomber I have my eye on the Crane H-278-2... 278/290* adv, 114* LSA and .467/.494" lift with 1.5 rockers (.498/.527" w/ 1.6s). Still cutting it close but I know the pushrod angularity takes out some lift at the valve.

BTW I'm already running the Hughes 1110 springs, even the small Voodoo requires good springs with its fast ramps.
 
The 1110s work for me, at .549 lift, on my Eddies, to well past 7500rpm

I'm not sure you understood my previous post.
-The stock ground 268/276 cam will not help your "pinging" situation, at all. To reduce/eliminate the ping there are a number of things that you can try(previously listed). To do it with the cam will require a later closing intake angle.
-IF your current compression ratio is EXACTLY 10.5, and if the current ICA (Intake Closing Angle) is exactly 60*, then an ICA of 66*, will reduce your Dcr from the current 8.64(which we know Pings under special circumstances), to 8.27, which may or may not cure that.We, or rather, I believe it will, with careful control of,timing and charge temperature.
-So any cam at all, that has an ICA of 66*ABDC will do it. I picked the 268, cuz you wanted to move the power peak up some 500/600 or so rpm.I suggested a cam LDA of 114, cuz that will put the installed CL at the correct 66* when installed 2* advanced. This gives you a little wiggle room to move the cam around to kill some Dcr if needed. And if it doesn't ping then maybe you can advance it some.See, if you are walking the tight line that you are with a 10.5 Scr, you have to be willing to put the time into it to help it survive.The pay-off comes when you get it dialed in, it will be a very hot SBM streeter; having gobs of low speed torque and a very strong powerband, and a decent top end charge.
-Now to finish up the cam talk; You are(as said) free to pick any cam you like that has the aformentioned 66* ICA. Then chose the Intake duration that will get you into the operating range you want(and that the heads will support). Then stick the max lift on there that will fit, that can be supported by the heads, and that the cam grinder is willing to supply. The exhaust duration can be the same as the intake, or if the heads need a little help, then add 6 to 10 degrees.
-Now, this is all small talk,cuz it all hinges on the IFs that I opened with.You will have to prove those numbers. Then call your favorite cam company and have a custom cam ground.Or if you cannot prove the 10.5 and 60*, do what I would do; retard the current cam until it stops pinging(after trying the easier things like slowing the rate of advance, and moving the all-in advance up a few hundred rpm, or otherwise messing with the timing). Then prove that ICA, and order up a cam.
-Just FWIW, I and others have successfully street-run Scrs over 11.2, with Dcrs of 9.2 or better, with aluminum heads. And,I have read of guys running 8.5 Dcr or better with C.I. , so you are pretty close. A little fine tuning of the timingS, may be all you need.
Best of luck to you.
 
If some smartass in brand X pulls up next to you at the lite,which gears
do you want out back?If you try using the "I don't have the traction" excuse,that's on you,
they sell the tires that do.
If the same smartass does that on the hiway,now which gears do you
want out back?If you try the "my car probably isn't safe at that speed" excuse,that's also
on you,it can be if you want it to.
Simply put,"street" means different things to different people, diabolical
pollsters!!
I have driven a car 145mph w/ a 4spd, that I drove later w 4.89's which
came in at about 4000rpm at 65mph w/275/60 15's. The eng. temps would slowly climb out
of control on my 1hr50min drive to the track,so economy being a mandate at the time,I put
a spraybar system in front of the rad. hooked to an extra washer tank& sw. to it.It worked
and a flip of the switch'd bring the gauge back to my temp. "comfort level".That's what I'd
put up with in my 20's,operating on a shoestring budget,never again these days.
The thing I hated most about RWD and going fast/steep gears,is the thobbing drone of
driveline vibration,can't stand it.Going 130 in the ShelbyZ you can hardly tell,the same in
any RWD regardless of the gear & you know it. OD trans does exactly the opposite I want
extra gears to do,give me 2.74's and 1 or 2 steeper lower gears and I'll pick a diff. to take
the extra torque thank you very much.
 
Killer6 said:
The thing I hated most about RWD and going fast/steep gears,is the thobbing drone of
driveline vibration,can't stand it.Going 130 in the ShelbyZ you can hardly tell,the same in
any RWD regardless of the gear & you know it. OD trans does exactly the opposite I want
extra gears to do,give me 2.74's and 1 or 2 steeper lower gears and I'll pick a diff. to take
the extra torque thank you very much.
Click to expand...

That only happens when you have incorrect driveline angles and/or out-of-balance driveshaft, also can be worn-out U-joints. How the heck do you think they got production-based RWD cars in NASCAR 60 years ago to achieve constant 180+ MPH for hours upon hours without shaking apart?

AJ/FormS I'm gonna PM you about the pinging/cam stuff I don't wanna hijack the thread any more lol...
 
MOPE
You're not totally correct, but close. When the angles are exactly the same, but in opposite directions, then the vibrations cancel out, and the natural body oscillations (drone) is less likely to be excited.
However it's not possible to run a street performance engine that way. The pinion angle has to be set for worst case situation, which is ;off the line, full-load,full-power,full-traction. This often requires a static rear angle of several degrees different from the front, often as many as 5* different.
Furthermore as the driveshaft speed increases it becomes increasingly more prone to come into the body occilation, and excites the drone.
And then there's those pesky oval mufflers. They love to get the body excited. And the faster the exhaust pulses come into it, the more powerful they become.
There are other contributors to drone as well; tire sizes come to mind and expansion joints in the hi-way.
BTW, a driveshaft can be perfectly balanced, yet excite the body. This is because of the way those pesky(there's that word again) u-joints transmit torque. When the joint is running at an angle, each of the cross-pins has to speed up and slow down on every revolution,and while it's doing this, the pin is moving in a for and aft direction.The more acute the angle, the more the scrubbing motion. This cannot be corrected by balancing, but only by a nearby opposite acting joint. I myself, don't exactly understand all this monkey motion, but I do know how to minimize it.
Getting back to your NASCAR example. Those guys were running flat out. So they can bias their drive-line angles to a much narrower window. And who knows what their car-bodies were naturally oscillating at . And mufflers? IDK. You see mufflers on Petty's Bird?
 
AJ/FormS said:
MOPE
You're not totally correct, but close. When the angles are exactly the same, but in opposite directions, then the vibrations cancel out, and the natural body oscillations (drone) is less likely to be excited.
However it's not possible to run a street performance engine that way. The pinion angle has to be set for worst case situation, which is ;off the line, full-load,full-power,full-traction. This often requires a static rear angle of several degrees different from the front, often as many as 5* different.
Furthermore as the driveshaft speed increases it becomes increasingly more prone to come into the body occilation, and excites the drone.
And then there's those pesky oval mufflers. They love to get the body excited. And the faster the exhaust pulses come into it, the more powerful they become.
There are other contributors to drone as well; tire sizes come to mind and expansion joints in the hi-way.
BTW, a driveshaft can be perfectly balanced, yet excite the body. This is because of the way those pesky(there's that word again) u-joints transmit torque. When the joint is running at an angle, each of the cross-pins has to speed up and slow down on every revolution,and while it's doing this, the pin is moving in a for and aft direction.The more acute the angle, the more the scrubbing motion. This cannot be corrected by balancing, but only by a nearby opposite acting joint. I myself, don't exactly understand all this monkey motion, but I do know how to minimize it.
Getting back to your NASCAR example. Those guys were running flat out. So they can bias their drive-line angles to a much narrower window. And who knows what their car-bodies were naturally oscillating at . And mufflers? IDK. You see mufflers on Petty's Bird?
Click to expand...

OK I definitely stand corrected lol, another treasure trove of info very nice. So what you're saying is, if/when I get a bit of vibration at high speed there's no real harm aside from it being annoying?

How do newer RWD cars do it, I'm guessing they don't use U-joints anymore? And probably have equal angles since they don't have to worry about the pinion moving up with a live axle and leaf springs...?
 
MOPEkidD-3 said:
OK I definitely stand corrected lol, another treasure trove of info very nice. So what you're saying is, if/when I get a bit of vibration at high speed there's no real harm aside from it being annoying?

How do newer RWD cars do it, I'm guessing they don't use U-joints anymore? And probably have equal angles since they don't have to worry about the pinion moving up with a live axle and leaf springs...?
Click to expand...
Many use one or none today.Some use one w/a rubber coupler at the rear,and yes,
IRS w/ a basically fixed diff minimizes this.Ask warren johnson and other pro stockers why
they switched to CV's instead of u-joints back in the 80's/early 90's. And who says cars
don't still do that today?I work these freakin junks every day, and many have the same
characteristic, and are instructed to tell the cust. it is normal. u-joints actually travel in
a tiny elipse at it's center.But cheer up sunshine,at almost half the century mark the one
thing I know for sure is,I learn something new all the time,and I'm happy to.
Oh, look under these new cars and check out the huge chunks of metal&rubber hanging
off of the diffs,exhausts,and tranny mounts,gee wonder what those are for?
 
Killer6 said:
Many use one or none today.Some use one w/a rubber coupler at the rear,and yes,
IRS w/ a basically fixed diff minimizes this.Ask warren johnson and other pro stockers why
they switched to CV's instead of u-joints back in the 80's/early 90's. And who says cars
don't still do that today?I work these freakin junks every day, and many have the same
characteristic, and are instructed to tell the cust. it is normal. u-joints actually travel in
a tiny elipse at it's center.But cheer up sunshine,at almost half the century mark the one
thing I know for sure is,I learn something new all the time,and I'm happy to.
Oh, look under these new cars and check out the huge chunks of metal&rubber hanging
off of the diffs,exhausts,and tranny mounts,gee wonder what those are for?
Click to expand...
LMAO well said. The new mopar products use vibration dampners all over.
 
roadrunnerh said:
3.23
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My brand new '70 Duster 340 had 3.23 open diff. 8.75 w/TF trans. Would do 138 (rallye pak 150 mph speedo) with me, 4 navy buddies, and a case of beer from Philly to Boston averaging a buck+. Talk about cringe- slapped on a set of "non-rated" snow tires from my previous '61 Impala with some aluminum adapters and the car would "only" do 120 (prolly more like 140+ 'cause the tires were a lot taller than the E70-14's the car came with). Used to pass herds of normal drivers at a buck+ using the breakdown lane. If a Plum Crazy Duster 340 did that to you on I95 45 years ago, I apologize. I was just, "Plum Crazy" back then.

Lost my license indefinitely after a 4 town "Dukes of Hazard" chase back home. Got passed by a cruiser (with it's lights and sirens on) on one of the same roads where the chase took place about 6 months after having my license pulled. I still think they knew it was me and was trying to scare me straight. It did, for a little while. That car had a "Demonic" personality that I loved.

Now I have a 383 Dart GT (1967) and just put a 3.55 SG in it after removing the 2.45 open diff. I haven't replaced the speedo gear yet, so an indicated 90 equals about 63 MPH @ 3,000 RPM and 120 equals 83 MPH. That's with 245/60-14 Cooper Cobra tires. Thinking about taller tires 'cause the 3.55's and small diameter tires (25") have killed my highway gas mileage. 3.23's would prolly have been a better choice, but the 3.55's are great around town. What a difference! And no more Demons.

View attachment IMG_0862.jpg
 
Now I can't wait to put my 3.23 in.
 
bobg450 said:
Lost my license indefinitely after a 4 town "Dukes of Hazard" chase back home. Got passed by a cruiser (with it's lights and sirens on) on one of the same roads where the chase took place about 6 months after having my license pulled. I still think they knew it was me and was trying to scare me straight. It did, for a little while. That car had a "Demonic" personality that I loved.


View attachment 1714845833
Click to expand...
Lol, I'd need both hands to count the # of times I took off and got away,lost
my license for racing in an industrial park.Oh yeah, emergency lane passing,for about a year&
a half my daily had some out of state guys& my carpool partner &I on the parkway to technical
school. Lets just say there weren't any rules to our road games!Today I wouldn't think about
evading the popo, two of mine were daytimes,the rest at nite.If they caught up to you today,
they'd order you out of the car,then shoot you for "reaching for something" undoing the
seatbelt!! I can't entirely blame them, but the days of just being a good ole boy are almost
completely gone,thanks to dealers,punks,and gangs that kill with about as much thought as
poppin open a can of soda.
 
toolmanmike said:
Now I can't wait to put my 3.23 in.
Click to expand...

Definitely- especially if you have 14" wheels like I have. The 383 has more torque than my duster 340 had (DUH). The 340 w/3.23's either burned or bogged out of the hole.

Did my first braked launch (TF trans.) from 2000 RPM and it went perfectly. Maybe 20' of minor wheelspin (both tires) and great weight transfer. Now to dial in the timing/AFR. It's a pretty much stock '69 charger engine, but felt like a low 14's/high 13's second car should feel.
 
Okay...I changed my mind, I was out ripping up the streets of Winnipeg all week-end and 3:91's are sure fun in and around town!
 
SSG_Karg said:
^ This x10!
I run 3.91s with a 28" tire and a non-OD 4 speed.. It turns 3k at 60mph and is a blast around town....:burnout:
Click to expand...

More proof it depends on where you are and what the roads are like... out here if you try to go 60 on the freeway you get passed by semi trucks, speed limit is 75 between towns and 65 in-town. Plus a lot of long straight back-country roads not like the up-down-left-right roads back east. My car cruises just under 3k RPM on the freeway with 2.94s and a stock-stall 904 trans, heck even with those gears sometimes I wish I had overdrive.
 
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