To big of a cam for that low compression. Plus 323's are for cruisers. Get some 430's. Put a plate on it with a 150 shot. Then you will be back on here asking what should I do to get it to hook up. LOL
What should I expect from 450hp?
- Thread starter Backally
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I saw your video. How did your car get crashed?
motor was dynoed/delivered with carb, ran it 2 years with that. Seemed similar. Got the issues straightened out with the sniper, still doing some tuning and working on the learning curve. Think the a/f is close but don’t know about timing. Idles at 20, cruise is 38, wot is 36 but looking at the table today it not all in till about 4K. Think I need to get that down.
B3422w5
Well-Known Member
there is about 3 to 4 tenths difference at the track.
Ken Hensley and i had that conversation years ago, its proven correct on many combinations, including a couple of nine. The worse the heads, the less the difference obviously. I have swapped mild eddies and seen the difference Hensley mentioned
Thats a significant difference. Likewise, making a gear change one step, say 4.10 to 4.30, 3.23 to 3.55, etc, rarely makes much difference at all, and if it does, its minimal
My main point wasn't there gonna be the exact same, Just seems like he started of with 340 and 3.73 and built a 408 for more torque but gave that advantage by going with 3.23 so it equaled it out a bit. Built a bigger engine basically not to go faster but make power lower to have a more streetable gear. Even though it still should be smoking the tires with a 408 and 3.23 my 360 smokes the tires with 2.94's.
I went from 3.73’s to 4.10’s without changing anything else and what you’re saying was true for my setup. Negligible at best at the track.
My son took it around the block after taking it out of the race trailer sitting for the winter . We raced it the year before and noticed wheel shake when the passenger side tire would land after the launch. Never thought much of it after looking at it at the track but were going to put in that tube K-member we made before the next season. so suspension was being replaced
We never put dawn dishwashing liquid in the new hoosiers so they would leak slow. So when we put it away we put the extra wheels on it from my 71 RR. 15x7's so it wouldn't sit with flats. He took it around the block and wanted to see how the 275's hooked compared to the 29 14.50's hoosiers. The shake was the Passenger cheap *** front UCA bolt stripped from the alignment shop. With the front runners the tire never hit the fender at the track or the short runs on the street.. With the 15x7s they hit when the tire moved back leaving off at the end of second. It cut the tire and took the car right off the road.
The spool didn't help things. The cage banged him up pretty good and broke a couple of ribs, He wasn't strapped in. I can replace the car which we will and it will be much faster. My son coming home was a blessing. The second last picture of the car leaving the driveway first time ever driven with these tires. The last pictures are what was usually on it. Never did this car have street tires. I should have left it sit with flats. Now you know. My son is 34 and had been racing sprint cars and ATVs since 16 nationally. **** happens.
I had that car a very long time and this wasn't its first bad wreck. We just clipped the car before painting it ford orange. Paint was free LOL. It started off life Bahama yellow when I bought it she was red. Then white, then orange and had its front clip replaced twice. body once. It had built 340's with iron heads. 340 iron head W2 motor, 428 aluminum batten head motor. and then this 416 indy. Been through alot since I bought it in 70's. I have a lot of pictures and videos of this car in all colors from over the years. This wasn't its last ride believe me. 7th picture is me and todd my neighbor when he worked for me . Man I wish I could go back to those years my energy level was so much higher. LOL.
So that is the history of the Duster and its demise. But there were many more you all never seen. I street races b-bodies since 71 and had some wild rides that I destroyed and survived.
![back4[2].jpg](https://www.forabodiesonly.com/mopar/attachments/back4-2-jpg.1715564427/ "back4[2].jpg")
We never put dawn dishwashing liquid in the new hoosiers so they would leak slow. So when we put it away we put the extra wheels on it from my 71 RR. 15x7's so it wouldn't sit with flats. He took it around the block and wanted to see how the 275's hooked compared to the 29 14.50's hoosiers. The shake was the Passenger cheap *** front UCA bolt stripped from the alignment shop. With the front runners the tire never hit the fender at the track or the short runs on the street.. With the 15x7s they hit when the tire moved back leaving off at the end of second. It cut the tire and took the car right off the road.
The spool didn't help things. The cage banged him up pretty good and broke a couple of ribs, He wasn't strapped in. I can replace the car which we will and it will be much faster. My son coming home was a blessing. The second last picture of the car leaving the driveway first time ever driven with these tires. The last pictures are what was usually on it. Never did this car have street tires. I should have left it sit with flats. Now you know. My son is 34 and had been racing sprint cars and ATVs since 16 nationally. **** happens.
I had that car a very long time and this wasn't its first bad wreck. We just clipped the car before painting it ford orange. Paint was free LOL. It started off life Bahama yellow when I bought it she was red. Then white, then orange and had its front clip replaced twice. body once. It had built 340's with iron heads. 340 iron head W2 motor, 428 aluminum batten head motor. and then this 416 indy. Been through alot since I bought it in 70's. I have a lot of pictures and videos of this car in all colors from over the years. This wasn't its last ride believe me. 7th picture is me and todd my neighbor when he worked for me . Man I wish I could go back to those years my energy level was so much higher. LOL.
So that is the history of the Duster and its demise. But there were many more you all never seen. I street races b-bodies since 71 and had some wild rides that I destroyed and survived.
9secRR
Well-Known Member
that cam is fine for 9.5:1 compression. i've ran way bigger cam , 621 lift with 9.5:1 compression. and i also ran 3.55 gears
Sorry, now I remember you showing pictures about that suspension bolt failure. Damn that was a big loss.
AJ/FormS
68 Formua-S fastback clone 367/A833/GVod/3.55s
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What's your elevation?
Time to dig out the compression tester.
IDK about 450/475, but my 367 with 3.55s spins the 325/50-15 BFG DRs to, they say, 90 plus mph. and it takes about 8and change seconds to hit a hundred.
With 295/50-15s that 367 busts the tires loose at 40,45,and 50 mph with 3.55s in second gear, with just a stomp on the ol' go-pedal...
Ima thinkin' that's what you should expect.
Ima thinkin when you go around a corner on those skinny wiener tires, you should go easy on the pedal else she will spin you around in a circle leaving you pointed backwards up on the median with at least one bent rim. That's what you should expect.
With 3.23s I would expect rubber into third gear, more than a chirp.
I would expect to have to baby the throttle below 35 mph in second gear so as not to spin those pizza cutter 245s.
I would expect a foot stomp in third gear to get you 85mph when you pass the driver's door, having pulled out to pass some slowpoke going 60 in a 65 zone.
I would expect in first gear with the line-loc applied, to bust the tires loose at little more than idle, and then you can reduce the throttle to churn the tires at 800 rpm, you laughing hysterically.
My 367 does all these things and more with 3.55s and a 230* cam.
Ima thinking your stroker with 3.23s should do the same ...... at least.
Ima thinking the 3.23s are just fine.
Ima thinking your tune is off. starting with your elevation.
My secrets are;
180psi cranking cylinder pressure.
Loose pistons and adequate ring gaps
fresh cold air, you gotta have it!
minimum coolant temp of 205 degrees, and a maximum of 207*.
87E10 fast burning gas,lol
full-length 3" duals.
a 750DP carb
Quick as a cat on fire, three guys are gonna jump in and say I don't need dual 3s all the way. And almost as quick one will say 207*F is too hot.
I'm not here to debate that. My car went 93 in the Eighth with these specs at 3457 pounds raceweight and at 930 ft elevation, on a HOT July afternoon, with a teensey weensey 230* cam; so tell someone who cares,lol.
If I had just one guess, I'd say you need more pressure and or to run a hotter water jacket..
Guys argue with me all the time, and I respect their opinions as most have more experience than me, but I'll tell you what I believe;
I believe that those aluminum heads suck tremendous amounts of heat out of the chambers, and when you stomp on the gas a lot of the energy in the fuel goes straight thru the heads and into the surrounding atmosphere, including cooking your intake.
To me it seems that they take a long time to heat up; in third gear I sometimes think I can feel it when the heat is finally staying in the chamber,and she starts to make power.
I did not know this when I originally assembled my engine, and I cannot even prove it's true. But I believe it.
To combat this behavior, I painted the heads three coats. and
I bumped the coolant temp up twice. Along the way, I had to loosen the pistons and loosen the ring-gaps, and figure out how to stabilize the coolant temp. And I increased the pressure and decreased the Quench, and I fed her air from above the hood, which made a radical improvement. All these things were done in an effort to reduce the heads from shedding heat thru the aluminum . And the results I think speak for themselves.
As to the full length 3" duals. I agree that they are generally overkill for the production of power. That's not why I choose them. I chose them to be heat sinks, to suck heat out of the exhaust as it is on the way to the mufflers. This reduces the volume of the gasses and they hurry thru the muffs. And then they cool some more on the way to the bumpers.
What this does is it reduces the pressure in the pipes which allows the overlap period to actually work.
Does it work?
IDK but the car went 93 with a stinking lil 230 cam.
Now; lets talk about your pressure. I looked it up and Wiki says you are up around 1900 ft elevation. And you stated 9.5 Scr, and said a 235* cam. Ima gonna translate that 235* @.050 into a 284 advertised, and I'll guess it's on a 114Lsa; you sound like a 114* kindof guy.And so I'll install it at 110 and get an Ica of 72*.
Here's what the Wallace has to say about that
Static compression ratio of 9.5:1.
Effective stroke is 2.92 inches.
Your dynamic compression ratio is 7.21:1 .
Your dynamic cranking pressure is 132.74 PSI.
V/P (Volume to Pressure Index) is 119
Notice the crappy 133 psi cylinder pressure, which translates to a VP of 119 which is what a LA318 makes. If this is correct, then you can fully expect your stroker to perform just like a 318 up to about 3000 rpm.
read about VP here; V/P Index Calculation
If I'm right, and sometimes I am, then this is your major problem. You will need to prove your pressure, and then figure out a way to pump it up into the 160s at the minimum, 170s preferred, and into the 180s to wake that beotch up!
Some guys here on FABO, claim pressure at or over 200psi still on pump gas.
My combos at up to 185psi, have all run on 87E10 with 32/34 degrees of power-timing, as early as 3400/3200 rpm.
Time to dig out the compression tester.
BTW, my BFGs don't leave blackies either after about one afternoon of driving them,lol. Not 245s, not 255s, not 275s, and not 295s That first few burn outs cooks em hard and after that, they are rollerskates. But they can last several summers like that, which makes it hard to justify taking them off. Good thing I have other cars to put them on.
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what were your ET's in a quarter with those 355's. 1000 RPMs with small tube open headers what fuel are you running? They all sound good at an idle with open headers . Blower motor with 8-1 same thing. Show us a video of it launching on pump gas with those 355's and 9.5-1 LOL. 9.5-1 my ***
AJ/FormS
68 Formua-S fastback clone 367/A833/GVod/3.55s
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I had 295/50-15 BFG T/A radials on my car. I never thought they were spinning, the auto trans felt a little mushy on the 1-2 shift and I was thinking I would have to rebuild it sooner rather than later. Car had 3.90 gear rear axle with a locker. 500-550hp 440 with ported heads, solid lifter cam and a really good Coan converter that stalled around 3000.
I was prepping to go to a track event and figured I would put some good tires on it. I bought some 325/50-15 Drag Radials. First time I drove it felt like I was getting shot out of a canon on the launch and the 1-2 shift caused the key cylinder and keys to launch out of the dash and into the back seat.
So, basically I had been driving it for a couple of years hazing the BFG T/A tires without realizing it.
9secRR
Well-Known Member
bone stock 1979 suspension, 8.25'' diff, 3.55 gears, premium 91 shell fuel. 12.05 @ 116 mph @ 3980 lbs. 1.58 60'. with the correct converter, i'm very confident i would have been 11.60's.
true measured and calculated 9.5:1 pump gas engine.
mini
Small Bore Long Stroke
Disagree. That's a small cam.
ir3333
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AJ/FormS
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"Small cam" yes of course,
but as @Oldmanmopar said; "Too big of a cam for that low compression",
And I add;
1) especially for a 3.23 geared, manual-trans streeter, which will likely spend the vast majority of it's life below 4000rpm,which is
~37mph in first/52 in second/71 in third/100 in direct.
Typically, I shift my 180psi 367 at 2800. That is more than enough to work traffic. And to accelerate briskly to 65mph, 4000 is way more than enough.
2) especially for aluminum heads which will easily accept 185 to 195psi cylinder pressure. Which at Part Throttle, that high pressure is simply amazing. Putting alloy heads on a 135psi stroker, IMO, somebody goofed; those heads will never reach their potential.
At a measly 7.3/1 expansion ratio, 135psi makes 986 psi in the chamber at WOT, at peak torque.
At 8.8, 175 makes 1540psi.
The latter is~ about 56% greater.In a streeter, I know which one I want.
_____________________
I'll give up 3 cam sizes for that latter. Oh wait, I already did.....
I will never ever go back to low-pressure, not with any engine in any car, and I don't care how many more than 3 speeds it has,lol. For as long as we can still buy at least 87 gas, I will continue to run 180/185psi, with alloy heads.
If I knew what @yellow rose knows, I would try a hi-pressure iron-headed beastie.
mini
Small Bore Long Stroke
While I would tend to agree with a dcr under 8:1 being a turd at low rpm you made a huge assumption on Intake closing degree not knowing the actual spec. That could be the difference between a 7.2 and an 8
AJ/FormS
68 Formua-S fastback clone 367/A833/GVod/3.55s
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OP gave us all the info we need, namely 235* cam and 9.5Scr. I wikied the elevation, and got 1900ft.
The advertised on a FTH 235@.050 cam is gonna fall into a very small slot of plus/minus 2 or 3 degrees, say ramps of 42 to 47 degrees. This makes the 235 to be about 277 to 282. I chose a 284, cuz that's a typical off-the-shelf cam in this range.
I installed it at 110, which takes the guess-work out of the LSA. That makes the Ica to be
180less {[(284/2)-110]+360}-284=72*....... At whatever, tappet-lift. Could be .008 with a Mopar/ Engle/ Hughes; or could be .006 with others. No big deal, to prove my point.
The next smaller cam will only change the Ica ~3.5*, and maybe 5 to 7psi, so not enough to create a big change in proving my point.
I hope this clarifies my post
Here is the same engine with an Ica of 69*
Static compression ratio of 9.5:1.
Ica of 69*, 1900ft elevation
Effective stroke is 3.01 inches.
Your dynamic compression ratio is 7.40:1 .
Your dynamic cranking pressure is 137.68 PSI.
V/P (Volume to Pressure Index) is 126
And at what it needs with that 235*/284cam
Static compression ratio of 11.5:1.
Ica of 69*/1900ft
Effective stroke is 3.01 inches.
Your dynamic compression ratio is 8.90:1 .
Your dynamic cranking pressure is 177.54 PSI.
V/P (Volume to Pressure Index) is 163
And for Ica of 72*
Static compression ratio of 11.85:1.
Ica of 72/1900ft
Effective stroke is 2.92 inches.
Your dynamic compression ratio is 8.92:1 .
Your dynamic cranking pressure is 178.08 PSI.
V/P (Volume to Pressure Index) is 158
yes you could run it at 8.0ish Dcr, like this;
Static compression ratio of 10.6:1.
Ica of 72*/1900ft
Effective stroke is 2.92 inches.
Your dynamic compression ratio is 8.01:1 .
Your dynamic cranking pressure is 153.70 PSI.
V/P (Volume to Pressure Index) is 137
But note that the VP is again feeble compared to what it could be. You could run this in a drag car no problem, cuz VP means nothing in racing. But on the street, Feeble VP shows up as a soft take-off. I get that the OP doesn't speak of a weak take off, and may already have found his problem with the not-audibly-complaining BFGs. But after he fixes that, VP is gonna become important. Well, with a stroker, maybe not.
But crickey, you can run 155psi on iron heads, and not have sprung for the alloys.
The advertised on a FTH 235@.050 cam is gonna fall into a very small slot of plus/minus 2 or 3 degrees, say ramps of 42 to 47 degrees. This makes the 235 to be about 277 to 282. I chose a 284, cuz that's a typical off-the-shelf cam in this range.
I installed it at 110, which takes the guess-work out of the LSA. That makes the Ica to be
180less {[(284/2)-110]+360}-284=72*....... At whatever, tappet-lift. Could be .008 with a Mopar/ Engle/ Hughes; or could be .006 with others. No big deal, to prove my point.
The next smaller cam will only change the Ica ~3.5*, and maybe 5 to 7psi, so not enough to create a big change in proving my point.
I hope this clarifies my post
Here is the same engine with an Ica of 69*
Static compression ratio of 9.5:1.
Ica of 69*, 1900ft elevation
Effective stroke is 3.01 inches.
Your dynamic compression ratio is 7.40:1 .
Your dynamic cranking pressure is 137.68 PSI.
V/P (Volume to Pressure Index) is 126
And at what it needs with that 235*/284cam
Static compression ratio of 11.5:1.
Ica of 69*/1900ft
Effective stroke is 3.01 inches.
Your dynamic compression ratio is 8.90:1 .
Your dynamic cranking pressure is 177.54 PSI.
V/P (Volume to Pressure Index) is 163
And for Ica of 72*
Static compression ratio of 11.85:1.
Ica of 72/1900ft
Effective stroke is 2.92 inches.
Your dynamic compression ratio is 8.92:1 .
Your dynamic cranking pressure is 178.08 PSI.
V/P (Volume to Pressure Index) is 158
yes you could run it at 8.0ish Dcr, like this;
Static compression ratio of 10.6:1.
Ica of 72*/1900ft
Effective stroke is 2.92 inches.
Your dynamic compression ratio is 8.01:1 .
Your dynamic cranking pressure is 153.70 PSI.
V/P (Volume to Pressure Index) is 137
But note that the VP is again feeble compared to what it could be. You could run this in a drag car no problem, cuz VP means nothing in racing. But on the street, Feeble VP shows up as a soft take-off. I get that the OP doesn't speak of a weak take off, and may already have found his problem with the not-audibly-complaining BFGs. But after he fixes that, VP is gonna become important. Well, with a stroker, maybe not.
But crickey, you can run 155psi on iron heads, and not have sprung for the alloys.
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Cam card below. Elevation here is about 900ft. I’m going to Hang a GoPro and see if tires are spinning, but it makes sense that they are...6k comes out to 56 mph and I’m not doing 20 mph to that in 2 seconds. Maybe it’s doing more that I think it is, especially with the 3:23’s. I got a 100+ mile cruise this weekend. Maybe after that I’ll put the 3:73’s in and see how it feels.
autoxcuda
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Great idea. Get some data.
These were the 1st gear calc’s I got:
2000 rpm = 18.5 mph
6000 rpm = 55.5 mph
Speed/Tire/RPM calculator
ir3333
Well-Known Member
It's the 380hp/360 crate engine, think the cam is 288/292 230/234 @ .050" .501"/.513" 108
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PRH
Well-Known Member
Sure looks like the cam is right in line with the OP’s overall combo to me.
The 412 cam is the middle one.
The 412 cam is the middle one.
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