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Discussion Starter #1
Hey fellow VMFers,

I came to me last night that there is a big difference between these two terms. Us newbies come on here asking how to make our cars faster and we usually get these elaborate stroker stories or upgrade suggestions but that isnt what us newbies are really after, we just dont know the difference.

SO as newbie let me know if I am on the right page.
I currently have a 67 coupe with a 302. AFR heads Air Gap intake yada yada yada. I thought I wanted the best performance mods for my car so i could take off from the light when these little rice burners pull up. So I went out and bought a 351 block with plans to build a 408 stroker.
It appears to me that what myself and a lot of other newbies on here really wanted was a gearing change. I dont need a car that can go 140mph (thats freakin scary). I need a car that when i push the accelerator the car goes very quickly.
a car with 3.55 gears will appear to be faster that a car with 2.78 gears is that correct.
To take this even farther, can gears offset displacement.
Will a modded 302 with 3.80 gears feel and appear faster than a comparably modded 351 with 3.25 gears?
 

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I believe that you are using the terms "faster" and "quickly" incorrectly yourself if I'm reading your question correctly.
You posted; "a car with 3.55 gears will appear to be faster that a car with 2.78 gears is that correct?"
A car with 3.55 gears will accelerate from a dead stop quicker than the same car equipped with 2.78's.
The 2.78's will be faster on the top end.
 

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SO as newbie let me know if I am on the right page. I thought I wanted the best performance mods for my car so i could take off from the light when these little rice burners pull up.
The "right page" would be not racing ricers from stop lights. There's already one adolescent exhibiting poor judgment at the light, why make it two? ;)

A car with 3.55 gears will appear to be faster than a car with 2.78 gears, is that correct?
If you mean would it accelerate more quickly off the line, then yes. (y)
 

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There are a LOT of variables. Steeper gears such as 3.73 will put an engine further up the RPM range faster. If your power band is high in the RPM range, it will definitely help the acceleration. In fact, if you have a built motor with horsepower not coming in until you hit 5-6 K RPMs it might feel like a real dog without some steep gears. However, if you have a motor with most of it's power coming in at low range, you might put it out of its optimum power band too quickly. First and second gear in the transmission figures in also. I remember a 67 Camaro with 4.11s and stock 327 that would come off the line like a rocket, he was going into fourth gear when I was still winding in 3rd and a second later my little A code 289 strolled right past him.
And then there is the fact that a lot of high torque motors that get along nicely with higher gears....they have the power to overcome those high gears.
 

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Amen Huntingky.
There are probably a dozen variables, all of which affect one another. The cams' power band, gears, weight of car, type of intake. I would seek out others with the same engine, car and tranny. Read a lot and take some time learning. Wish you had the same engine as me, as I have been thru it all. I LOVE a quick hole shot, and to have a fast quarter miler and decent gas mileage all at the same time. That is the trick. The new aggressive ramp cams help.
 

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Hey just look up torque vs horsepower.

Torque = quick
Horsepower = mph/fast
 

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I definitely disagree with you, accelerating off of a light is NOT illegal. Street racing however is. So is speeding. Theoretically if you accelerated quickly off a light and do not exceed the speed limit you would not be breaking any laws and not endangering any lives.

Also how is having a “ricer” poor judgment. You sound like a fun guy to be around.
 

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After all the engine mods and gear change you’ll still be limited to how fat a tire you can put under it.
 

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I definitely disagree with you, accelerating off of a light is NOT illegal. Street racing however is. So is speeding. Theoretically if you accelerated quickly off a light and do not exceed the speed limit you would not be breaking any laws and not endangering any lives.
In California, what you are describing is (or was) considered "exhibition of speed" and is most definitely illegal. Engaging in a speed contest is also illegal and will result in a hefty fine and car being impounded. In my younger days, I was cited for both and lost my license for 6 months and paid the fine!
 

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Discussion Starter #12
The original point of this post was to differentiate the two quick vs. fast. Like I said I dont need to go 140 mph. I rode 130 on my motorcycle scary as hell. When I wasa younger i had a nissan 240 and got it up to 95 and it was scary as hell.
After all of the research tht I have done, Top end seems overrated for a street car. I dont plan on ever going to a track
I know this question will come up (it always does)
302 coupe,wti AFR 185 heads, headers, Air Gap intake Edelbrock performer Cam, Dual exhaust with roller rockers. A Holley 600 Carb C4 transmission with 2200 stall torque converter and 17 inch rims with Nitto semi slick tires on the rear. And once again no aspirations of ever going to a track
 

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Discussion Starter #13
Ok guys these responses are going left real quick. First of all for anyone on here to say that they have never floored it or tried to see how fast their car could go . I am going to go ahead and say you are a liar.
There is nothing wrong with pullin up at a light and having a little fun with another car enthusiast. Im not talking about racing for pink slips or cash Im talking about having fun.
Come on guys relax
 

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To refer back to my first reply to your question, A bigger number rear end gear will be what you are looking for if it's a quick street machine your after. The trick is to determine the best ratio for your mix of street and highway usage. Is gas mileage even a consideration?
 

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Discussion Starter #15
To refer back to my first reply to your question, A bigger number rear end gear will be what you are looking for if it's a quick street machine your after. The trick is to determine the best ratio for your mix of street and highway usage. Is gas mileage even a consideration?
No gas mileage is not really a concern, the car will be driven at most once a week on sundays, maybe twice in the summers.
Right now I am looking at installing some 3.80 gears. I was considering 3.55 but I just found a great deal on a pumpkin with posi and 3.8 gears
 

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There are a LOT of variables. Steeper gears such as 3.73 will put an engine further up the RPM range faster. If your power band is high in the RPM range, it will definitely help the acceleration. In fact, if you have a built motor with horsepower not coming in until you hit 5-6 K RPMs it might feel like a real dog without some steep gears. However, if you have a motor with most of it's power coming in at low range, you might put it out of its optimum power band too quickly. First and second gear in the transmission figures in also. I remember a 67 Camaro with 4.11s and stock 327 that would come off the line like a rocket, he was going into fourth gear when I was still winding in 3rd and a second later my little A code 289 strolled right past him.
And then there is the fact that a lot of high torque motors that get along nicely with higher gears....they have the power to overcome those high gears.
I always got a kick out of the NHRA Stock Eliminator class. Remembered seeing the specs for a '68 camaro that was running 10.8s. Don't have it book marked. Rules are strict, stock heads no porting, stock size valves... Shift points were over 8,000. I think he was running 4.56 gears. I'll see if I can find it later. ( no one here may be interested but I want to find it anyway). This was in the early 2000's. I think the car was called ol' reliable. It was a small block

Not the source I remembered but same car. it was 5.57 gears. shown at the end of the page. http://z28camaro.com/old-reliable/ same guy, next car
The sound is just awesome.
 

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I definitely disagree with you, accelerating off of a light is NOT illegal. Street racing however is. So is speeding. Theoretically if you accelerated quickly off a light and do not exceed the speed limit you would not be breaking any laws and not endangering any lives.
Depends on local laws. In Nebraska, there is a law against any "contest or display of speed or acceleration". You can be ticketed for what (solely in the cop's opinion) was an unnecessarily quick acceleration away form a light, breaking traction, etc. Doesn't matter if you kept it under the posted speed limit. Go ahead, try to fight it -- good luck with that.

So, if you're going to roast that little twit in the wanna-be car in the other lane, just make sure no one sees you do it. Better yet... make sure there IS a cop around, and let the other guy get the ticket.
 

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No gas mileage is not really a concern, the car will be driven at most once a week on sundays, maybe twice in the summers.
Right now I am looking at installing some 3.80 gears. I was considering 3.55 but I just found a great deal on a pumpkin with posi and 3.8 gears
65/66 Shelbys typically came with 3.89 gears. The 3.80's would be fine as long as you do not expect to do a bunch of highway driving at 80 mph. I say get the posi pumpkin and give them a whirl. If you find you do not like them you can change them out.

As others have said, traction is the limiting factor. Any given tire on a particular car will break loose when a certain amount of torque is applied. The rear end ratio serves to multiply the torque. A set of 3.80 gears is going to apply about 7% more torque to the tire than a 3.55 set of gears. If the tire to road combination can handle that torque without spinning, you will accelerate faster with the 3.80 gears.

"Will a modded 302 with 3.80 gears feel and appear faster than a comparably modded 351 with 3.25 gears?" - It will feel "quicker" if the 302 produces 85%, or more, of the torque the 351 does at launch RPMs and then gets into it's power band as quickly or quicker. The 351 does have an internal advantage of a 16% longer stroke. Does that translate into 16% more torque? Hard to say as there are too many variables.
 

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While one would think the law is clear, in the real world its subjective, and its often up to the accused to hire legal counsel to prove otherwise . I once got a ticket for disorderly conduct because my Monte Carlo SS chirped the tires shifting into second gear. In the same car I was also accused of going over 100mph simply by sound by a state trooper who had another car pulled over when I passed on the highway at 65mph. The car had 4.11 gears!
 
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