340 or 408?
- Thread starter 67_Slimer
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67_Slimer
Real Hot Rods don't shift themselves.
What cubic inch does that come out to? Also , those heads must flow insane numbers? I wish I could afford W2's
PRH
Well-Known Member
These threads always devolve into discussions about “theory”, and end up losing sight of the original post.
The fact is, an Ede headed 408 on pump gas with a modest, easy on parts roller cam is a slam dunk no brainer for 500+hp……… and contrary to “internet wisdom”, it will not be all done making power at 4900.
The fact is, an Ede headed 408 on pump gas with a modest, easy on parts roller cam is a slam dunk no brainer for 500+hp……… and contrary to “internet wisdom”, it will not be all done making power at 4900.
abodyjoe
Well-Known Member
if just those two choices i think i'd go with a 408. seems guys make 500HP by accident with them. i think it would be less high strung then the 340 at those hp levels too..
what about a 416 from a stroked 340? that should be easy to get 500 hp from too..
9secRR
Well-Known Member
355'' and head flow is 286 @ 650 lift
9secRR
Well-Known Member
W2's are cheap. look around, you can buy heads, rockers, intake for $2500-3000
67_Slimer
Real Hot Rods don't shift themselves.
And the bold right on LA style small block? What about the exhaust ports? Would I need new headers? Are they cast iron W-2's?
9secRR
Well-Known Member
Yes they bolt small blocks. LA headers do work as long as the heads have dual bolt pattern. I used LA headers for 8 years with W2 heads. The heads are iron.
67_Slimer
Real Hot Rods don't shift themselves.
May I ask which version of W2 head you have?
9secRR
Well-Known Member
810’s
A stock W2 isn’t going to make the horsepower he is looking for. And it’s getting harder everyday to find someone willing to port cast iron.
67_Slimer
Real Hot Rods don't shift themselves.
Would my ported Eddys give what I need?
I told you earlier if you get your Edelbrock heads and Victor340 intake ported you can easily make 550 with a stroker. That is if you get the right guy doing the porting work. Don’t mess around with a 2.02 valve. Jump up to a 2.055 intake valve. Years ago my stock W2 heads flowed 260cfm&.450 lift then fell on their face and went down rapidly.
We had a very very nice roller cam that we wanted to put in this engine that was given to my son by a friend. It was a .660 lift cam that could have taken better use of my heads. We didn’t have valve to piston clearance using the SRP flat top (250.00 pistons) so we used the 100.00 Reed cam. I about cried when this cam was damaged when a bar on a comp roller lifter broke letting the roller lifter turn sideways.
If shooting for more like 550 hp your probably gonna need some sort of stroker not that a 340 can't make 550 hp just most of that gain gonna be 5500-7000 + rpms at least you have 4.56 gears but the higher rpms you make the power at the harder it is to get into the powerband at normal road speeds 20-50 mph.
Peak power doesn't matter so much on the street, the gearing for your car is fixed so that means the rpms at normal road speeds through the gears is fix, say at 10-80 mph through the first few gears, Eg.. say were generally talking 3000-6000 rpm is the range you spend most of your time at full/heavy throttle, that's where you want most of your gains doesn't mean you want your engine to peak in 3000-6000 rpm range an engine that peaks at 6500 rpm probably have better 4000-6000 rpm than a engine that peaks at 6000 rpm.
Your the designer/engineer your designing/modifying to make the powerband work the way you want/like.
The 340 guy's are gonna recommend 340 and 408 guy's are gonna recommend 408 etc..
Where is you car weak where do you want it stronger ? If the bottom end is fine and you want a lot more top end 5500-7000 rpm probably don't need a stroker or much of one (3.58" might do).
Seem like you got a decent 340 bottom end, maybe just upgrade to Trick Flows or port the Eddie's on the engine you got and if you find you need more bottom end power then go stroker. Would be the way I'd do it, make decisions off baseline results instead of shots in the dark.
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furrystump
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I can’t make a cam recommendation, I’m only smart enough to know I have no business doing it. The process of picking one, sure, nail down EVERYTHING else about your build. Head flow, intake, CI, stroke, approx weight of car, rear gear, rear tire size, fuel, static compression, rocker ratio, header size, because you have a stick, no converter to deal with, then realistically what you want to do with it. Then talk to a good cam company to get a recommendation.
67_Slimer
Real Hot Rods don't shift themselves.
In the end of it all , I guess I'm such a mopar purist that I would like to try and stand by a standard 340 and try to make do with that. I had every intention on building a 360 based stroker when I couldn't find a reasonably priced 340 but if this 340 comes through , I hope to make it work.
PRH
Well-Known Member
One good thing about this hobby is………you can do it however you want.
67_Slimer
Real Hot Rods don't shift themselves.
I can understand a numbers matching build. It has stock wheels, tires, gears, exhaust, intake so forth and so on. Just like it was factory built. Peppy little car. Cool cruiser. Neato. I truly understand it
I also understand hotrods. You have a car that's been altered, to achieve "x". Maybe now it's a 10 second street brawler. Neato.
Now... what I don't understand is ... you're willing to modify all kinds of things on your car. 456 gears, aftermarket everything. But.... heaven forbid....we can't change that crank stroke. It's like, the least intrusive mod in the book. Hell in a SB Mopar with a 4" crank, most of the time you don't even need to clearance the block. Or it's very minimal. And, I suppose.. . you could easily put a stock stroke back in.
I can't for the life of me understand this.
I also understand hotrods. You have a car that's been altered, to achieve "x". Maybe now it's a 10 second street brawler. Neato.
Now... what I don't understand is ... you're willing to modify all kinds of things on your car. 456 gears, aftermarket everything. But.... heaven forbid....we can't change that crank stroke. It's like, the least intrusive mod in the book. Hell in a SB Mopar with a 4" crank, most of the time you don't even need to clearance the block. Or it's very minimal. And, I suppose.. . you could easily put a stock stroke back in.
I can't for the life of me understand this.
Newbomb Turk
Well-Known Member
He doesn’t want a stroker. What’s hard not to grasp?
Some of us don’t care to drive tractor engines.
67_Slimer
Real Hot Rods don't shift themselves.
Like PRH stated before , that's the beauty of our hobby , we get to do whatever we want. I'm old school and always liked 340s. I had a lot of fun with my 340 and want to build another one. Not much to understand. There's not a single thing stock on my car so that's not the issue at all , just my preference. I can go on all day but it's just my opinion. I could ask the same reason why everyone wants to build stroker motors. I respect all builds but I like what I like. Sorry if I offended anyone in the process.
67_Slimer
Real Hot Rods don't shift themselves.
Thank you Newbomb.........Don't drink the punch!!
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