as soon as the results are available i will post them , hope the numbers are better this round or i'll trash this engine and concentrate on my 340 rebuild. my car always died at the top of the 1/4 mile track , ran out of hp
408 Stroker
- Thread starter 70dart340
- Start date
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In Washington State, the best we get at the pump is 91 Octane. I know people with aircraft, (wink,wink, so I have access to 95 Aviation. But for y street hotrod, 91 is the best our communist govenor will sell us at the pump.
I'm paying attention to all the information coming in. Please feel free to add your input/opinions. I'm talking to my machine shop this week. I know that nobody built a statue to a committee, but I'm listening to all points of view. A horsepower point of view, not political view. That crap is available for anyone.
famous bob
mopar misfit
One makes more power always “IF”....what “IF” there “IS” no option for “IF” but only “IS” like there “IS” one 750 on a tunnel ram, a rat roaster , single plane or a dual plane? Not changing anything else. I think we all know which one will make the most power, but only “IF”..... So “IT” depends on what the definition of “IF” “IS”!
--------------IF , the biggest word in sports or racing !!
famous bob
mopar misfit
depends on what it made of !!! hahahahahaha-a 100 cubic ft of air , b.s. !!
A cube with 100ft sides= one Million cubic ft, NOT one hundred cubic ft.
yellow rose
Overnight Sensation
No, you did not. I asked you specifically about making air turn corners. I asked when is that a GOOD thing, and why is it a good thing.
So you didn’t answer it. Try again.
OK. Just to clarify again. A cube of air with sides 100 ft long weighs 38 tons. Mopar Sam is correct that it is one million cu feet. Sorry for any confusion.
For the non-believers, the formula for calculating weight [ mass ] when density & volume are known is very simple: M= D times volume. Density at sea level is 1.29 kg/ sq. m.
For the non-believers, the formula for calculating weight [ mass ] when density & volume are known is very simple: M= D times volume. Density at sea level is 1.29 kg/ sq. m.
Just under 500 hp, with 600 ft lbs of tq as low as 2600 rpm. Edel RPM intake.
No, not a 408 Chrys, but a 455 Pontiac. These were impressive #s because the engine had factory iron heads & QJ carb. 10:1 CR, 236/242 @ 050 cam. Nothing very fancy.
I do not know how to link the page, but is on the PYOnline.com forum.
In the Street section, thread: Dyno results 462.
No, not a 408 Chrys, but a 455 Pontiac. These were impressive #s because the engine had factory iron heads & QJ carb. 10:1 CR, 236/242 @ 050 cam. Nothing very fancy.
I do not know how to link the page, but is on the PYOnline.com forum.
In the Street section, thread: Dyno results 462.
famous bob
mopar misfit
still dont believe it !!
So the bottom line is I should get the TF single plane, and put my 750 mechanical secondary Quick Fuel on it to start. It's not a DD, it's a stock appearing Scat Pack member, with the performance to back it up. I have a NIB MSD E-Curve distributor I bought on sale in 2008. Does anyone have any experience with this dizzy? Please continue to add to my knowledge data base. All positive comments are appreciated. Paul.
famous bob
mopar misfit
John Collins
Well-Known Member
It’s hard to believe, but it’s true... It’s Science. If you want your mind blown, read the next sentence. The average cumulus cloud weighs 1 million pounds.
famous bob
mopar misfit
Yeah , thats why they float around in the sky , right !?
I'm not going to agree or disagree with the weighs. BUT!
Air has mass, air has weight. Your car push this mass away every time you drive your car.
The faster you go the more residence you get.
If air didn't weigh anything then the wing on the back of your car would be worthless.
Air has mass, air has weight. Your car push this mass away every time you drive your car.
The faster you go the more residence you get.
If air didn't weigh anything then the wing on the back of your car would be worthless.
Ivoryk3ys78
Well-Known Member
As far as compression ratio that should be based around the camshaft choice and when the intake valve closes. I would try to optimize your cylinder pressure. This will help you keep a lot of your bottom end even with a healthy cam. I would certainly also zero deck the block.
You can find good articles on this by David Vizard. I would shoot for 190psi on 92 octane.
I used the wallace racing calculator to come up with my numbers
So for my engine at 11.2 compression with a 0 deck and .039 gasket and -13cc pistons and the 60cc TF 190 with my elevation and cam closing at 65 ABDC that calculated out to right at 190 PSI. When we checked my cylinder pressure after the engine was built they are all in the mid 190 area.
Also try to match the dish piston up or whatever your doing so you do have a quench area that is fairly tight like at most .040 area. This will help get a better combustion and have less chance of detonation. I have not noticed any issues with mine.
I think one of the big reasons a single plane engine may show such lazy bottom end is partly because the cylinder pressure was not optimized for the cam and a duel plane likely help mask that.
You could certainly run a duel plane and it would of course have a ton of torque in lower rpm range. However you would be choking down the flow of the 190 heads. I guess a person has to experience it to really believe it but you will definitely not lack for torque with a 4 inch crank. it will be a broad torque curve especially with well matched components and a good torque converter.
Wallace Racing: Dynamic Compression Ratio Calculator
Wallace Racing: Dynamic Compression Ratio Calculator
Also there is a good episode of Engine Masters where they did a DP VS Single plane test. The cam was not that big it was in the mid 230@050 if I remember right. They figured the RPM would destroy the single plane. The single plane won hands down. They figured one of the reasons was that he head they were using was a real nice head.
You can find good articles on this by David Vizard. I would shoot for 190psi on 92 octane.
I used the wallace racing calculator to come up with my numbers
So for my engine at 11.2 compression with a 0 deck and .039 gasket and -13cc pistons and the 60cc TF 190 with my elevation and cam closing at 65 ABDC that calculated out to right at 190 PSI. When we checked my cylinder pressure after the engine was built they are all in the mid 190 area.
Also try to match the dish piston up or whatever your doing so you do have a quench area that is fairly tight like at most .040 area. This will help get a better combustion and have less chance of detonation. I have not noticed any issues with mine.
I think one of the big reasons a single plane engine may show such lazy bottom end is partly because the cylinder pressure was not optimized for the cam and a duel plane likely help mask that.
You could certainly run a duel plane and it would of course have a ton of torque in lower rpm range. However you would be choking down the flow of the 190 heads. I guess a person has to experience it to really believe it but you will definitely not lack for torque with a 4 inch crank. it will be a broad torque curve especially with well matched components and a good torque converter.
Wallace Racing: Dynamic Compression Ratio Calculator
Wallace Racing: Dynamic Compression Ratio Calculator
Also there is a good episode of Engine Masters where they did a DP VS Single plane test. The cam was not that big it was in the mid 230@050 if I remember right. They figured the RPM would destroy the single plane. The single plane won hands down. They figured one of the reasons was that he head they were using was a real nice head.
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Hi, I have a 426 SB stroker set up for street use. My recommendation for you would be to go for the roller cam setup since you tore the engine apart already, as well as fuel injection.
Keep in mind that since you are stroking a SB everything that you put will be undersized, this means the intake, cam, etc. you need to go one or 2 steps beyond what you would do in a standard small block simply because the stroker drws more air into the engine.
For fuel if possible I recommend you to go EFI sniper or the edelbrock pro flo will do the job.
Compression depends on what heads you will be using. I recommend to go aluminum since this will save you front end weight as will do the aftermarket aluminum intake. Try to get forged internal but not heavy parts like eagle rods or so, get them as light as you can by design. Molnar HW is excellent.
There is abook calles big inch small block mopars I believe which has very useful info, pictures and tips for a mopar stroker build.
I hope the info helps.
Keep in mind that since you are stroking a SB everything that you put will be undersized, this means the intake, cam, etc. you need to go one or 2 steps beyond what you would do in a standard small block simply because the stroker drws more air into the engine.
For fuel if possible I recommend you to go EFI sniper or the edelbrock pro flo will do the job.
Compression depends on what heads you will be using. I recommend to go aluminum since this will save you front end weight as will do the aftermarket aluminum intake. Try to get forged internal but not heavy parts like eagle rods or so, get them as light as you can by design. Molnar HW is excellent.
There is abook calles big inch small block mopars I believe which has very useful info, pictures and tips for a mopar stroker build.
I hope the info helps.
Everything helps, Ivan. Thank You. Since I already have a Quick Fuel Mechanical Secondary, 750 CFM, Super Street with the down leg annular boosters and 4 corner idle, I'm going to try that first with the TF 190's and the matching SP manifold. I'll get corrected squared block height this week. Thanks to all. Paul.
I started with a 750cc edelbrock carburetor and an airgap manifold, it worked fine because my mechanic is an expert on old cars but later since I installed larger intake valves in the edelbrock RPM heads and decided to swap the carb for EFI, I gained around 10HP but now I can tune it since I moved and didn't have any shop references where I live now. At least from the self and DYI adjustment perspective it has been excellent to have EFI.
I see in one of your postings your previous setup made 520 HP and 560 FT/LBS with 10.4 CR, the Air Gap and a 242/[email protected]”/.603” lift 106LSA cam. What where the changes you made afterwards? Looks like you barely gained any meaningful horsepower but lost a good chunk of torque.
also at what altitude was this dyno run, and confirm if this is crank HP
Ivoryk3ys78
Well-Known Member
Sorry your not happy with the results.
I'm sure you posted this before but can you refresh the vital engine stats? I know you went from a RPM to a SP..Victor? What chamshaft do you have ? solid or hyd? What compression.
Thanks a lot. Sorry it didn't turn out how you wanted.
QUOTE="Nat, post: 1973383347, member: 56408"]RESULTS ARE IN 527 hp @5800 529tq @4200 not impressed the engine is going in storage with the other junk i collect , going to build another 340 less power but i won't have to stop at the gas station once a day for a tank of gas , drive 120 miles a day , it adds up @ 50.00 a tank[/QUOTE]
I'm sure you posted this before but can you refresh the vital engine stats? I know you went from a RPM to a SP..Victor? What chamshaft do you have ? solid or hyd? What compression.
Thanks a lot. Sorry it didn't turn out how you wanted.
QUOTE="Nat, post: 1973383347, member: 56408"]RESULTS ARE IN 527 hp @5800 529tq @4200 not impressed the engine is going in storage with the other junk i collect , going to build another 340 less power but i won't have to stop at the gas station once a day for a tank of gas , drive 120 miles a day , it adds up @ 50.00 a tank[/QUOTE]
only changes were victor and 13cc pistons replacing the 23cc dish pistons cam is as you posted. **** it going in the scrap pile on with the next project
cyl pressure is 185
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