FE Power Forums
FE Power Forums => FE Technical Forum => Topic started by: Dan859 on October 21, 2014, 02:31:09 PM
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Hi everyone,
First, I'd like to thank all those who responded to my post on the 427 stroker build. Thank you! There were a lot of interesting and informative points made and I appreciate everybody's time.
I've thought about it and at this point my plan is to install a stroker kit, new cam, new heads/intake, and sell the HR pieces to help finance the new parts. My goals are to have 600HP, a hydraulic roller cam, either a dual quad carb setup, or possibly an 8 stack EFI system (if I have the money after building the engine!), and have a street friendly setup. Any advice to help refine this further would be appreciated, and I have a few questions.
First, for a stroker kit, what are the pros and cons of a 4.250 vs. a 4.375 kit?
Second, for the heads, I'm looking at either a set of Survival or BBM heads. Based on what I've read so far, both seem like they would be a good choice, I think it depends on price and availability. What should I be looking for in regard to valve sizes, porting, and port matching?
For the intake, my choices seem to be a dual plane such as the BT, or a tunnel wedge such as the Dove/BBM, or possibly a stack style EFI. I'm on the waiting list for Jay's intake adapter, so I'm thinking of using that, as there are both dual quad and EFI units available for it. If I go with the dual quad, I'm thinking I should simply give the engine particulars to Quick Fuel and go with what they suggest.
For the camshaft, I know that depends somewhat on which stoker kit I choose, but what would be a good profile for either choice?
Thanks in advance for the help.
Dan
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If you went 4.375", I would really re-think the use of the HR heads. There seems to be an aversion to using old-school pieces by a lot of people, but in all honesty, they still work very well with supporting parts. It would certainly save you some coin, considering you're now looking at buying new heads, a new intake, plus the entire rotating assembly.
If you're 100% decided on buying new heads, I would use the BBM pieces. I've had them in my hands, have carved on them, have flowed them, etc., so I have experience with them. I'm not biased towards any head because I don't have cash tied up in an investment....with that being said, as soon as I can get a pair of Barry's heads in my hands, I would love to see them and use them.
On the carb and cam, you'll need to wait until you have figured out which stroke you use, which head you go with, etc. All of those have a huge bearing on the cam selection.
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I have an obvious biased on heads... :)
But I can say that the heads have been run for two years in the Engine Masters Challenge
They have been ported with good results by several third party folks - JDC and Mummert have reported their results here.
There are roughly 60 pair out in public circulation with another forty pair coming here inside of a week (assuming shipping goes as planned/wished/desired/promised/prayed for...). So far the feedback has been pretty positive.
I cannot really comment on the BBM parts. Maybe I can trade Brent for a pair of castings...
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Maybe we can talk BP into doing a BBM/Survival dueling 390 test again...... ;)
I was being serious about reusing the old iron....there's just something about using factory pieces and making big horsepower. If you get into the frame of mind that you're going to not add CSA or volume, but try to add flow and add velocity at the same time, it will be a win/win all the way around.
To the OP, you know how big a tunnel port head is.....we went from 340 cfm to roughly 380 by making the CSA *smaller*....
Use that old iron! Stick it on a 4.250/4.375 combo and let it eat.
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First, for a stroker kit, what are the pros and cons of a 4.250 vs. a 4.375 kit?
The only "drawbacks" to that long of a stroker crank is one being the side-loading of the cylinder walls, which would be an issue on old factory thin walled blocks, not so much your very strong Genesis block. Second, if I'm not mistaken, the 4.375 gets very close to the oil ring land on the piston, but if I recall correctly can be done without the pin intruding on the ring with the correct rods and custom pistons.
Otherwise there is no drawback to a longer stroke except maybe a limiting of RPMs, which is more than offset by the extra cubes and power.
I'll let the engine guys help you on the refinement, but I'd tend to figure out what intake/look I wanted to go with because that will influence the rest of the engine build as well, in regards to intake pathway, porting, valve sizes etc. But I will say I do like all of your mentioned choices :)
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Maybe we can talk BP into doing a BBM/Survival dueling 390 test again...... ;)
I was being serious about reusing the old iron....there's just something about using factory pieces and making big horsepower. If you get into the frame of mind that you're going to not add CSA or volume, but try to add flow and add velocity at the same time, it will be a win/win all the way around.
To the OP, you know how big a tunnel port head is.....we went from 340 cfm to roughly 380 by making the CSA *smaller*....
Use that old iron! Stick it on a 4.250/4.375 combo and let it eat.
Brent,
Nothing "old iron" about it, they were Dove HR heads.
Now if we really wanted to see how the BBM and Survival heads compare then Barry should just trade Blair for the set thats on they dyno comparison engine and run it again...see exactly where they stack up!
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Good point, forgot they were doves.
Regardless, with some cubes and a little work, they would do just fine.
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I can say that you would have no regrets with Felony heads from Barry, and they're American made. Pristine quality. Tremendous power on pump gas; the old HR heads won't tolerate low octane as well with the old chamber design.
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Brent, here is one for you since you said you like old school, C4 block, 4.25 stoker,C4 iron hi riser heads, tunnel wedge and QF 750 carbs,even running a flat tappet comp cam.
its for a t bolt clone so i wanted to stick with mostly factory hi riser stuff
built by one of Jays buddys Kurt. let me know what you think of these numbers
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(http://fepower.net/Photos/Posts/johnpdyno4.jpg)
(http://fepower.net/Photos/Posts/johnpdyno1.jpg)
(http://fepower.net/Photos/Posts/johnpdyno3.jpg)
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Nice motor Johnp427!
How much open spring pressure did you need to control that XTQ intake valve? I've used a much smaller XTQ and needed a fair amount of spring pressure along with titanium retainers to keep in under control.
Any other engine spec's you care to share? Compression, intake manifold, carb?, headers, etc.
thanks,
paulie
edit: Oops. Now I some engine spec's in the previous post. What was the compression though?
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Paul, the static compression wound up being 12:3
i think its listed on the sheet with the cam info
cant wait to hear it run in the car but on the dyno it actually idled pretty decent around 850
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Yes sir, atta boy.....
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Paul, the static compression wound up being 12:3
i think its listed on the sheet with the cam info
cant wait to hear it run in the car but on the dyno it actually idled pretty decent around 850
I see now, John. How 'bout them valve springs??? I ask because I've used that family of intake lobes before and had some trouble keeping it happy, at a lower rpm than you're running.
JMO,
paulie
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Good job JohnP !
Goes to show what can be accomplished with "old iron" in the right hands.
Nice to see something different.
All the newer heads that are coming out are great but hard to not like the old school builds.
This stuff can be made to run but takes someone with the knowledge that's willing to make it happen.
Would like to hear what was done as far as the port mismatch with the HR heads and Tunnel wedge intake or was it a HR intake.
Also how high octane fuel are you running ?
Hope Dan reads this before abandoning his initial HR project.
If you have a dyno video put it up for us to listen to.
garyv
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Gary V, it is a high riser tunel wedge so port mis match wasnt a big issue other than the standard port gasket match, motor was run on 110 fuel but prob will mix 110 and pump gas for street use and maybe pull a little timing out. Im happy with results, not sure how these numbers compare with other similar combos but i think for old chunks of steel they did pretty good, no expert but the VE numbers look good, not sure about BSFC numbers,maybe one of the experts can chime in.
Curious how it will run on street, if its going to be lazy down low and peaky,i do think the extra cubes helped.