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Hey fellas just picked up a 89 notch. Car has a semi built motor 306 with gt40x heads. What should this combo run. I’m thinking 12.50s or so. Here is a list of the mods.
306
Gt40x Heads
Performer rpm intake
650 Holley carb
F cam
9.0 compression
1.6 roller rockers
Mac shorty headers
Mac off road H pipe
Flowmaster exhaust
Tremec 3550 trans
3.73 gears
Stock suspension
275 60 15 drag radials
Ac delete.
Am I in the ballpark thinking it should go 12.50s. Thanks
 

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Depending on what part of the country your in it might run 12.50s with some good traction and shifting. If you live in the deep south you can forget it until January. The heat and humidity of the south in the summer will kill the horsepower.
 

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pretty much the same combo but i had UPR upper and lower control arms i went [email protected] mph
 

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If you live in the deep south you can forget it until January. The heat and humidity of the south in the summer will kill the horsepower.
Absolutely correct! Driving home today and went to pass another car; dang car felt like a modern N/A 4 cylinder....104° air temp with 79° dewpoint...360'MSL. Gutless pig!


Those who race in higher altitudes will suffer the same issues. Denver? Forget it....Maybe a low 14/high 13 sec. My brother's old car would run 13.30 at Bandimere. Here it ran 12.50 and no changes were made. '69 Torino/429.
 

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There is no way to say. Those parts in the hands of an experienced NMRA racer is very different than those parts in the hands of Joe Average.

Could be anywhere from 10s to 14s.

My guess is it has the POWER for somewhere between 11.5 - 12.5 ish but that won't happen on the first pass and might not happen without some suspension mods and driver practice. How do you guess when you have guys with good aftermarket parts that make 260 rwhp and then you have guys running worked over stock iron over 350 rwhp.

But you give those parts to an experienced racer and he will have the stuff running low 10s.

Best advice is to drop 20 bucks at the local strip and find out.
 

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Let me share my secret proprietary (not really) methods for ricer math.

Figure out how fast you want to go. 12.5 ET

Divide 1335 by target ET. 1335/12.5 = 106.8 this is the approximate trap speed you need to get there.

Then figure out what your race weight with driver is. Either guess and be wrong or find a scale. 10 bucks at the truck stop should do the trick.

Lets say your car with driver is 3100 lbs.

Put it all into this calculator and let me stress THIS CALCULATOR not any other random one you find on the internet. http://www.angelfire.com/my/fan/WHPCalculator.htm

You find that you need 250.6 RWHP for that trap speed in that car.

This should get you in the ballpark of what your stuff is capable of being run in the roughly 95th or so percentile of what it is able.

This means this is a nearly best case number if you have your stuff SQUARED AWAY. That means the chassis and driver have to be able to use the power CLOSE to max potential.
 

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The method Taco posted is very accurate. Here is my example: Know RWHP = 362 HP Best pass was an 11.13 @ 120.5 MPH.

1335/11.13 = 119.95 MPH

From the website:

Your stang weighs 3080 pounds and reaches 120.5 mph at the end of the 1/4 mile. Output is about 357.62 HP at the wheels.

The lockup from my AOD generates the MPH, but not the ET on the back end of the track.
 

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Flyin' Ryan...here's my suggestion.

Forget this forum, and the answers. GO TO THE TRACK and have fun with it. If you feel like it, post up the results. If not, blow it off. If you're happy with it, stick with it, if not, repair and make another trip to the track to try it out.

Seat time. That is the only way you'll know what it'll run; and the only way you'll know what you need to do to make it faster. OH, and by the way....it's addictive if you haven't already figured it out :)

Reason I say that is because I am a member of several forums and sites, some of the are local. I see a lot of projects going on but I rarely see these guys at any of the local tracks. What's discouraging is watching the projects...especially the high end stuff...guys put hundreds of thousands into them, then lose interest, never hit the drag strip or anything, and eventually sell out. My brother is guilty. I have never put that kinda money into a vehicle and don't plan to, but I beat on the stuff that I do have and have been successful with it. Ain't nothing pretty, nothing fast, but gets the job done and I have fun messing with it-which is the root of the sickness. If it weren't fun, I won't do it...and yes there was a time when it became no fun, and I quit for a while. Nowadays, a few times a year and I'm good with that. Quit chasing money and points, jackets, hats, all that stuff, and it's FUN again.
 

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Flyin' Ryan...here's my suggestion.

Forget this forum, and the answers. GO TO THE TRACK and have fun with it. If you feel like it, post up the results. If not, blow it off. If you're happy with it, stick with it, if not, repair and make another trip to the track to try it out.

Seat time. That is the only way you'll know what it'll run; and the only way you'll know what you need to do to make it faster. OH, and by the way....it's addictive if you haven't already figured it out /forums/images/smilies/smile.gif

Reason I say that is because I am a member of several forums and sites, some of the are local. I see a lot of projects going on but I rarely see these guys at any of the local tracks. What's discouraging is watching the projects...especially the high end stuff...guys put hundreds of thousands into them, then lose interest, never hit the drag strip or anything, and eventually sell out. My brother is guilty. I have never put that kinda money into a vehicle and don't plan to, but I beat on the stuff that I do have and have been successful with it. Ain't nothing pretty, nothing fast, but gets the job done and I have fun messing with it-which is the root of the sickness. If it weren't fun, I won't do it...and yes there was a time when it became no fun, and I quit for a while. Nowadays, a few times a year and I'm good with that. Quit chasing money and points, jackets, hats, all that stuff, and it's FUN again.
Amen man. Well said. Problem is, it’s never fast enough!! So there starts the never ending $$ pit. Awesome hobby though!
 

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TODD TURBO

What Todd said. Just go to the track and have fun. Will the car go into the 12's Yes, but will you do it first night out Nope. I started out going 12 seconds with the same car I have now that goes high 8's and it is making within 50 horsepower its entire life.
 

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i agree with Todd here... it takes a special type of nut job to stay building a car for year after year. 99% of people cant do it. its always best to do things here and there and keep having fun with the car. having a car down year after year is tough on anyone. mines been down doing on 2 years, i had planned on finishing it this year but life got in the way. lucky for me the work with the X car gets me my fix till mines done
 

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Where's the timeslips?
depending where hes trying to race if its anywhere in the mid atlantic he would have been better of trying to race boats lately
 
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