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Re: 12s in a challenger with a stock bottom 340? [Re: B3RE] #1830222
05/19/15 06:13 PM
05/19/15 06:13 PM
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BLACK71 Offline OP
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BLACK71  Offline OP
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Originally Posted By B3RE
9.5:1 CR
224@.050 duration
273 rockers
2.02/1.6 pocket ported irons
Air gap w/750 Edelbrock/650-700 Holley
1-5/8" headers/2.5" duals

= = = = = = =

12's on a budget!

Want more?

Upgrade to 1.6:1 roller rockers, and correct the geometry.
Get a good 32-3500 converter


Read the tech articles on your site, very interesting!!! When will more be posted? Any suggested reading or "how to" on fixes


RMNS 10:9-10
Re: 12s in a challenger with a stock bottom 340? [Re: BLACK71] #1830239
05/19/15 07:02 PM
05/19/15 07:02 PM
Joined: Feb 2005
Posts: 20,163
PA.
pittsburghracer Offline
"Little"John
pittsburghracer  Offline
"Little"John

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PA.
Originally Posted By BLACK71
Originally Posted By B3RE
9.5:1 CR
224@.050 duration
273 rockers
2.02/1.6 pocket ported irons
Air gap w/750 Edelbrock/650-700 Holley
1-5/8" headers/2.5" duals

= = = = = = =

12's on a budget!

Want more?

Upgrade to 1.6:1 roller rockers, and correct the geometry.
Get a good 32-3500 converter


Read the tech articles on your site, very interesting!!! When will more be posted? Any suggested reading or "how to" on fixes




When Mike started posting on Moparts he came on pretty strong in some of his posts and to myself I said ya, ya, ya. Heard the story before BUT I bookmarked his website and would drop in once in awhile. With small cams I was always able to get it within a tolerance I was ok with. But not this time. I was jumping from a 550 lift solid lift cam to a 670 lift roller cam. I spent 2 full days in the shop with my 408 trying every trick I've ever tried. I was at a point of either going with a different cam or giving Mike a chance. Called and talked to him and ordered his system and all is well. Call and talk to him and you WON'T be disappointed. I will post more on this after this weekends testing and race.


1970 Duster
Edelbrock headed 408
5.984@112.52
422 Indy headed small block
5.982@112.56 mph
9.42@138.27

Livin and lovin life one day at a time




Re: 12s in a challenger with a stock bottom 340? [Re: pittsburghracer] #1830276
05/19/15 08:09 PM
05/19/15 08:09 PM
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Posts: 561
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B3RE Offline
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Thanks John!

I may have come on strong, but someone who believes strongly in something certainly can't be wish-washy, or no one will believe in them. Actually, that may have been my survival instincts coming out. If you recall, I got beat up pretty bad for a while. grin
I'm anxious to hear some results on the 408. Let her rip! drive


Mike Beachel

I didn't write the rules of math nor create the laws of physics, I am just bound by them.
Re: 12s in a challenger with a stock bottom 340? [Re: BLACK71] #1830288
05/19/15 08:23 PM
05/19/15 08:23 PM
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B3RE Offline
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Originally Posted By BLACK71
Originally Posted By B3RE
9.5:1 CR
224@.050 duration
273 rockers
2.02/1.6 pocket ported irons
Air gap w/750 Edelbrock/650-700 Holley
1-5/8" headers/2.5" duals

= = = = = = =

12's on a budget!

Want more?

Upgrade to 1.6:1 roller rockers, and correct the geometry.
Get a good 32-3500 converter


Read the tech articles on your site, very interesting!!! When will more be posted? Any suggested reading or "how to" on fixes


I write the tech articles as I get the time, and the last one was just posted last week. It may be a little while until I can get the next one up there, depending on how backlogged I am with work. The only real fix is to relocate the rocker shafts to get everything in the right place. There are two ways to accomplish that. Mill the stands off of the heads and have someone who knows proper valvetrain set up make new stands, OR, use a bolt on kit like the one John put on his 408. Also, just milling off the stands, and making new stands, to center the roller on the tip of the valve will not correct geometry, and will likely result in valvetrain instability and possible failure.


Mike Beachel

I didn't write the rules of math nor create the laws of physics, I am just bound by them.
Re: 12s in a challenger with a stock bottom 340? [Re: cudadoug] #1830516
05/20/15 01:01 AM
05/20/15 01:01 AM
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Posts: 883
Affton MO
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qwkmopardan Offline
super stock
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Affton MO
Originally Posted By cudadoug
Originally Posted By pittsburghracer
Most of our Mopars members over cam their small blocks. Matts 1970 duster runs 10.50's with a 520 solid Racer Brown cam at over 3000 pounds.


ST-21 cam? 254* @ .050??


My Demon went 10.40s with a st-21 w/1.6 RAR in a KB190 piston 360/371 w/ ported 587 production heads and Victor intake at 3100#. Idled in gear at 800RPM. It sounded like a stock engine with open headers at the race track, but ran like a scalded dog. I sold engine to a buddy which put in a street Duster w/ Air Gap intake, less converter and gear, 3.73s, which has only ran 12.70s on BFG radial TAs, smoking the tires but reaching 109mph. Next trip to track will have drag radials and should run low low 12s or high 11s. Very drivable go anywhere anytime , let your wife, mom, grandma, anyone drive it!

Re: 12s in a challenger with a stock bottom 340? [Re: B3RE] #1830656
05/20/15 10:51 AM
05/20/15 10:51 AM
Joined: Jan 2003
Posts: 24,562
Brookeville, Md
Mr.Yuck Offline
Not enough dumb comments...yet
Mr.Yuck  Offline
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Posts: 24,562
Brookeville, Md
"Btw, what does the compression do for it?"

compression = horsepower.

Re: 12s in a challenger with a stock bottom 340? [Re: Mr.Yuck] #1830666
05/20/15 11:14 AM
05/20/15 11:14 AM
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B3RE Offline
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Originally Posted By Mr.Yuck
"Btw, what does the compression do for it?"

compression = horsepower.


No, Torque x RPM / 5252 = Horsepower

The compression raises cylinder pressure, which increases torque across the curve, which equates to more horsepower at a given rpm. Cam duration and timing events will also affect cylinder pressure and rpm range. Instead of dumping a bunch of compression in a motor to pick the bottom end up when the cam is too big, why not pick the cam for the intended rpm range, set the compression ratio accordingly, and still have the needed cylinder pressure? I contend that most cam choices are too large for the intended usage or capability of the heads and induction, and compression is used to crutch the lower rpms to keep it from being a slug.


Mike Beachel

I didn't write the rules of math nor create the laws of physics, I am just bound by them.
Re: 12s in a challenger with a stock bottom 340? [Re: B3RE] #1830672
05/20/15 11:22 AM
05/20/15 11:22 AM
Joined: Jan 2003
Posts: 24,562
Brookeville, Md
Mr.Yuck Offline
Not enough dumb comments...yet
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Posts: 24,562
Brookeville, Md
I'm saying that if you can build a 10.5:1 motor it will make more power than an equally prepared 9:1 motor.
"I contend that most cam choices are too large for the intended usage or capability of the heads and induction, and compression is used to crutch the lower rpms to keep it from being a slug."
I do agree with that.

Last edited by Mr.Yuck; 05/20/15 11:23 AM.
Re: 12s in a challenger with a stock bottom 340? [Re: dustergirl340] #1830673
05/20/15 11:22 AM
05/20/15 11:22 AM
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Posts: 20,172
Park Forest, IL
slantzilla Offline
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Park Forest, IL
Originally Posted By dustergirl340
Quote:

The Challenger is probably 800lbs heavier.


My husband's small block '72 Challenger weighs 3,340 pounds. My small block '73 Duster weighs 3,300 pounds. Both all metal body full interior street cars.


My '72 smallblock Challenger weighed 3600 with 3 people in it. Small block Challengers are not nearly as heavy as people think.


"Everybody funny, now you funny too."
Re: 12s in a challenger with a stock bottom 340? [Re: Mr.Yuck] #1830690
05/20/15 11:42 AM
05/20/15 11:42 AM
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B3RE Offline
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Originally Posted By Mr.Yuck
I'm saying that if you can build a 10.5:1 motor it will make more power than an equally prepared 9:1 motor.
"I contend that most cam choices are too large for the intended usage or capability of the heads and induction, and compression is used to crutch the lower rpms to keep it from being a slug."
I do agree with that.


Yes, it does have that capability, but we are talking about a strong running street car, with a street gear, needing to go 12's, without walking the detonation highwire. To stay out of detonation, it would need a big enough cam to bleed off cylinder pressure at lower rpm, but the cam would want to pull at a higher rpm than the rest of the combination requires. I may be wrong, but I suspect the OP will spend more time on the street, at street rpm levels, than at the track wringing it out until it's gasping for air.
I agree the compression will help power all the way through the rpm range, but I would rather have the combination be spot on and get the best useable power for the application over the whole rpm range.


Mike Beachel

I didn't write the rules of math nor create the laws of physics, I am just bound by them.
Re: 12s in a challenger with a stock bottom 340? [Re: B3RE] #1830705
05/20/15 12:16 PM
05/20/15 12:16 PM
Joined: Jan 2003
Posts: 24,562
Brookeville, Md
Mr.Yuck Offline
Not enough dumb comments...yet
Mr.Yuck  Offline
Not enough dumb comments...yet

Joined: Jan 2003
Posts: 24,562
Brookeville, Md
Originally Posted By B3RE
Originally Posted By Mr.Yuck
I'm saying that if you can build a 10.5:1 motor it will make more power than an equally prepared 9:1 motor.
"I contend that most cam choices are too large for the intended usage or capability of the heads and induction, and compression is used to crutch the lower rpms to keep it from being a slug."
I do agree with that.


Yes, it does have that capability, but we are talking about a strong running street car, with a street gear, needing to go 12's, without walking the detonation highwire. To stay out of detonation, it would need a big enough cam to bleed off cylinder pressure at lower rpm, but the cam would want to pull at a higher rpm than the rest of the combination requires. I may be wrong, but I suspect the OP will spend more time on the street, at street rpm levels, than at the track wringing it out until it's gasping for air.
I agree the compression will help power all the way through the rpm range, but I would rather have the combination be spot on and get the best useable power for the application over the whole rpm range.


which is why I said use as much compression as you can. He is not at sea level either so the goal will be a tad tougher.

Re: 12s in a challenger with a stock bottom 340? [Re: BLACK71] #1830770
05/20/15 01:46 PM
05/20/15 01:46 PM
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JCCuda Offline
mopar
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Here are two 360 combos that i have run. Very similar cast piston short blocks but different hydraulic cam and different converters. The bigger cam as expected needed a looser converter. If I was going to do the 360 in the Duster over I would stick to a 224@.050 cam with a 108 or less lobe separation like I had used in the Valiant but with a looser converter then the Valiant.The other difference is transmissions (727 Duster) (904 Valiant). Below I copied and pasted 2 of my previous post.

This is my Duster,
Finally got the Duster into the 11's. After I lost first round cause I sucked driving the finish line I decided to take some weight out of the car and see if I could get into the 11's. I weighed the car before the 1st time shot 3,495lbs. with me in the car. 1st. t/s the car went a 12.182/109.57 2nd. t/s 12.180/109.79. 1st. round 12.137 on the brakes was going a 12.12 something going off the 1000' so I didn't kill much. As I mentioned I sucked driving the finish line cause I was .004 on the tree. Anyhow since I had lots of time to kill I took out the spare tire and the 50lb. plate that I had under the tire along with all the hold down hardware and went up and made a t/s the car went 12.022/110.81 with a so far best 60' of 1.640 I weighed the car after the pass 3,390lbs. Next I took out the pump spray bottle from behind the seat and a small toolbox and I cooled the car down to 105 degrees go in the water at 125* and the line at 135* the car went 11.943/111.80 and 1.634 60' weight after that pass was 3,370. It's not bad for a cast flat top 360, 9.9 compression, 232/237@.050 hyd., mild pocket ported 2.02/1.60 J heads, LD340 vac.750, heddman 1-5/8" header, 3" summit exhaust with dynomax ultraflows, point's dist. with a super coil, 3.91 gears, 255/60/15 M/T drag radials, 727 trans.. It gets driven on the street but not to far because I have a water pump drive on it and an 8" converter right now. Any suggestions on making it go faster without spending money are welcome.

This was my Valiant,
My 360 started as a .040 over Napa rebuilt short block. I took it apart to check everything. I had the block decked (deck .015 head 63cc., gasket .028, compression 10.51)reversed the cast dished pistons on the rods and put in good rod bolts and had the rods resized. I put in an old Manley cam that I had. 443 lift 224@.050 I don't remember the lobe seperation but I think it was around 108. I used J heads pocket ported with 2.02 int. valves and 273 adj. rockers an LD340 intake with a 1" 4 hole spacer and a Vac. 750. For exhaust I used heddmen 1 5/8" headers, 3" exhaust with ultra flows ending at the axel. I used a 904 with a Dayco 2,400 stall converter and an 8 3/4 with 3.91's the slicks were 8"x 26"x 14". Suspension consisted of 6yl. bars and comp. eng. adj. shocks in the front and 002/003 superstock springs with Mopar perf. 50/50 xtra long shock in the rear. The car was a 70 Valiant 4 door it weighed 3,320 with me in it. With an electric water pump drive, 5/16" fuel line with holley mech. fuel pump and a homemade fresh air intake (dryer hose and a dual snorkle air cleaner)the best run was 11.96/113 but it typically went 0's and teen's in decent air at Atco and E-Town. Typical 60'was low 1.70's. With a looser converter maybe around 3,500 stall it probably would have gone 11.70's or 80's.


Duster 2013-11-03 13.16.31.jpgValiant Atco.jpg
Last edited by JCCuda; 05/20/15 01:48 PM.
Re: 12s in a challenger with a stock bottom 340? [Re: Mr.Yuck] #1830832
05/20/15 03:02 PM
05/20/15 03:02 PM
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B3RE Offline
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We are both after the same thing, and that is cylinder pressure. We just have different approaches.
I accounted for the altitude in my suggestions by recommending a little more compression, and camshaft, than I actually used in the build that eventually went 12.30s. That build started at 8.8:1 and had a 218 @ .050" cam with 273 rockers and it went 12.90s. It was at 9.06:1 with the same cam and 1.6 roller rockers for the 12.30s.


Mike Beachel

I didn't write the rules of math nor create the laws of physics, I am just bound by them.
Re: 12s in a challenger with a stock bottom 340? [Re: BLACK71] #1830849
05/20/15 03:26 PM
05/20/15 03:26 PM
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CA
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crackedback Offline
top fuel
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JCCuda - Awesome results.

Shows what little in camshaft has to go into these SB's to get them to run well. Love the 4 door!!!

Re: 12s in a challenger with a stock bottom 340? [Re: B3RE] #1830880
05/20/15 03:58 PM
05/20/15 03:58 PM
Joined: Jan 2003
Posts: 24,562
Brookeville, Md
Mr.Yuck Offline
Not enough dumb comments...yet
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Posts: 24,562
Brookeville, Md
Originally Posted By B3RE
We are both after the same thing, and that is cylinder pressure. We just have different approaches.
I accounted for the altitude in my suggestions by recommending a little more compression, and camshaft, than I actually used in the build that eventually went 12.30s. That build started at 8.8:1 and had a 218 @ .050" cam with 273 rockers and it went 12.90s. It was at 9.06:1 with the same cam and 1.6 roller rockers for the 12.30s.


Of course he could solve his altitude woes buy adding 6-8psi of boost. laugh2

Re: 12s in a challenger with a stock bottom 340? [Re: Mr.Yuck] #1830941
05/20/15 05:19 PM
05/20/15 05:19 PM
Joined: Feb 2005
Posts: 20,163
PA.
pittsburghracer Offline
"Little"John
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PA.
I got a good one to tell you how easy this is to get a small block in the 12's. 35+ years ago I sold my 1972 Duster to a good Friend and he asked if I would build a 340 engine for him. We took a stock 340 block and honed it, reconditioned stock rods, stock pistons out of a 1970 340, stock crank, LD340 intake, a set of 2.02 valve heads that I polished when I knew NOTHING, an 850 double pump carb, and a 484 lift purple shaft hydralic cam. He was into dirt track racing so up to this day he only had a 15 second car down the dragstrip. My Duster with him in it was app 3100 pounds. The car had a spool, 4.56 gears, 727 trans, and the thing that made this package work was a 4200-4400 stall Turbo Action convertor. He drove it some on the street and we were confident with it so knowing we only had 2 time trial gave he heck on the first pass. When he came back and saw the 12.28 ET time slip he was shaking like a leaf. Here's a picture of the car.

my first duster 001.jpg

1970 Duster
Edelbrock headed 408
5.984@112.52
422 Indy headed small block
5.982@112.56 mph
9.42@138.27

Livin and lovin life one day at a time




Re: 12s in a challenger with a stock bottom 340? [Re: pittsburghracer] #1830945
05/20/15 05:22 PM
05/20/15 05:22 PM
Joined: Feb 2005
Posts: 20,163
PA.
pittsburghracer Offline
"Little"John
pittsburghracer  Offline
"Little"John

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Posts: 20,163
PA.
It ran 11.82 with a slightly better engine when I owned it and it was still on the street.

My old Duster at Keystone 001.jpg

1970 Duster
Edelbrock headed 408
5.984@112.52
422 Indy headed small block
5.982@112.56 mph
9.42@138.27

Livin and lovin life one day at a time




Re: 12s in a challenger with a stock bottom 340? [Re: pittsburghracer] #1830965
05/20/15 05:52 PM
05/20/15 05:52 PM
Joined: Jun 2005
Posts: 5,102
Western Md.
skicker Offline
"The Champ"
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I've come to the disappointing conclusion I probably can't hit the 12's with a 3.23 gear. frowwn Car feels good but I think its at about the 13.30's. shruggy 3.91 gears are ready to go in...that should do it up but I'm on the fence since a newer design looser convertor may work better...maybe something in the 4500 range... work

Dads Slots 1.jpg

...FAFO...
Re: 12s in a challenger with a stock bottom 340? [Re: pittsburghracer] #1831092
05/20/15 09:41 PM
05/20/15 09:41 PM
Joined: Aug 2003
Posts: 3,245
Between a rock & a hard place
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cudadoug Offline
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Between a rock & a hard place
Originally Posted By pittsburghracer
It ran 11.82 with a slightly better engine when I owned it and it was still on the street.


Describe this better engine that you speak of...

Re: 12s in a challenger with a stock bottom 340? [Re: cudadoug] #1831101
05/20/15 09:52 PM
05/20/15 09:52 PM
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Posts: 463
Rescue CA.
joes68340s Offline
mopar
joes68340s  Offline
mopar

Joined: Oct 2010
Posts: 463
Rescue CA.
Love the Dart.

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