A different Q on 340 Vs 416

[1Fast340]

Still far from sure on where to go with my build and are mostly benchracing here,but here is something i have thought about.
What i have is a 73Duster With PB and PS (the last two things might change before this is done)

Weight last it ran was 3185lbs with me in it and a full tank of gas and a bunch of tools.
It does have subframeconnectors
904Transmission
32-3500RPM converter(i cant remember) its very nice and tight.
RPM Airgap manifold (also have a Edelbrock Tunnelram)
800cfm Edelbrock AVS or 750Proform mech secondary carb
Some very nicely ported Edelbrock RPM heads but still with the stock 2.02/1.60 valves
TTI 1 7/8" headers.
Comp XE 280R a small solidroller camshaft with 242/248 @.050" and .570/.576 lift

Here comes the real question the thing has a 8 1/4" suregrip rear with two available gear ratios.
I have a fresh bored 340 block that is .030" over with two fresh forged stock cranks just sitting and i also have a set of Eagle H-beam rods and would aim for about 10.5-11:1 or so compression on pumpgas.
Would you either build a:
stockstroke 340 with 3.91:1 gears
or a 416 4"stroker with 3:21 gears
With this bunch of parts?
Im sort of thinking that the difference in gear ratios would be equaled out so to speak by the gearing,except for idlequality that i dont find being much of a problem anyway.
For maximum performance the thing would obviously need more gearing with any of the options,but this is just fun car.



There are more options including a Lysholmtwinscrew and a E85 dominator but the options above are the ones that seems least stupid and wont eat blocks and drivelineparts as often.

 

[Wyrmrider]

I'd start wit a survey of piston weight given the cr you want and the head cc's
Then figure the max FPS you want those pistons to move- ask the piston mfg
what max rpm do you want to turn with each
what valve springs would it take- you evidently do not want to go to high maintenance grind-
keeping same cam- when does it quit pulling/ max rpm
then work backward
would be really fun with the stroker and the 3:91's but maintenance may not be so much fun and wopuld take a much bigger cam if going for max- not so for a sat night machine

I like the cu inches- but you say you already have good cranks so you can't hide the stroker kit in a new crank-- what's the delta in cost?
the blower can add 200 hp without too much boost

 

[MOPAROFFICIAL]

Even with a 4-inch crank it's not going to be optimal with the 3.21 gear and that cam.

It will run good though and you can always add gear

 

[Garry in AZ]

I'll take a different approach, and ask how and where will the car realistically be driven for the vast majority of the time? If it's going to see a lot of track time, then you really need to look into the technical side of things and determine what will be best for the ET slip you're chasing. The previous replies offer good advice in that regard.
But, you said it's a "fun" car, which to me implies that it will mostly be driven on the street with maybe only a few dragstrip passes once in a while. If that's the case, I'd go with the stroker. For stoplight to stoplight fun and the pure thrill of sticking your foot in it once in a while, nothing beats cubic inches. Having to rev the motor to the moon to go quick isn't as much fun on the street. Lots of low RPM torque, is!
Admittedly, I'm an "old guy" but I have seen many guys build cars that might be really good drag race cars, and then only take them to the track twice a year, but put on 4000 miles going to cruise nights and car shows. They end up with a car that's not as much fun to drive on the street, even though that's where the car actually spends the majority of it's time.
Be honest with yourself when making these decisions and in the end you'll end up with a car that's a blast to drive, plenty fast, and a joy to own.

 

[Treblig]

I'll take a different approach, and ask how and where will the car realistically be driven for the vast majority of the time? If it's going to see a lot of track time, then you really need to look into the technical side of things and determine what will be best for the ET slip you're chasing. The previous replies offer good advice in that regard.
But, you said it's a "fun" car, which to me implies that it will mostly be driven on the street with maybe only a few dragstrip passes once in a while. If that's the case, I'd go with the stroker. For stoplight to stoplight fun and the pure thrill of sticking your foot in it once in a while, nothing beats cubic inches. Having to rev the motor to the moon to go quick isn't as much fun on the street. Lots of low RPM torque, is!
Admittedly, I'm an "old guy" but I have seen many guys build cars that might be really good drag race cars, and then only take them to the track twice a year, but put on 4000 miles going to cruise nights and car shows. They end up with a car that's not as much fun to drive on the street, even though that's where the car actually spends the majority of it's time.
Be honest with yourself when making these decisions and in the end you'll end up with a car that's a blast to drive, plenty fast, and a joy to own.

Yep!! If you don't know where you're going before you begin your journey you'll get lost and waste time (and money)....

Treblig

 

[1Fast340]

I'd start wit a survey of piston weight given the cr you want and the head cc's
Then figure the max FPS you want those pistons to move- ask the piston mfg
what max rpm do you want to turn with each
what valve springs would it take- you evidently do not want to go to high maintenance grind-
keeping same cam- when does it quit pulling/ max rpm
then work backward
would be really fun with the stroker and the 3:91's but maintenance may not be so much fun and wopuld take a much bigger cam if going for max- not so for a sat night machine

I like the cu inches- but you say you already have good cranks so you can't hide the stroker kit in a new crank-- what's the delta in cost?
the blower can add 200 hp without too much boost

Pistonchoices are not realy a problem will just get some light of the shelf forged pistons that gets me as close to the compression i desire as possible and will cut the heads for final adjustment of compression that part is no big deal,one of those stock cranks has been to and beyond7500rpm countless times with the same rods with heavy TRW pistons in a different block but with a whole bunch more cam in the past
The heads are already set up with the right springs for the cam so no big problem there either
Last i ran the car it had that cam and heads(those heads where way to good for that poor block) in a 11:1 340 with completely worn out bores and those TRW pistons where beat to death,shifted the thing at 6800-7000rpm. and figure i would shift a new 340 with the same cam and heads at about that rpm. its was a very nicerunning engine but worn out.
Figure the same combination of parts in a 416 would be shifted at just alitle over 6000rpm

The thing would probably be mostly a saturday night car,going to carshows,cruisenights drive it on nice summerdays and the occational 1/4mile run but just for fun, have seen way to many cars become trailerqueens and never driven and then the owners lose intrest.
Im figuring that staying stock stroke would cost a couple hundred dollars less when its all said and done compared to say a castcrank/forged piston scat kit.
Biggest reason for the small diffrence staying with one of my stock cranks would be that i would end up having to cut the heads a bunch more to get good compression and might also need pushrods at that point,
Taking in the whole picture since the thing needs new studs/arpbolts a new oilpan and preferably some new rockers aswell, and all the other odds and ends that always ends up costing an arm and a leg a few hundred dollars for a crank/strokerkit is not the end of the world.

Im confident the thing will make alitle shy of 500HP regardless of stroke,reason for the gearchoices is that i like to be conservative there to make it a more enjoyable drive and the stockstroke combo works well with 3:91gears but i also figure a 416 with the same parts would have enough torque to not realy be bothered by a bunch less gear and still be plenty exciting to drive that way.

That screw would make things exicting very quickly,but i also think it would be wasted to risk destroying stockblocks with it,i know myself all to well and that thing would be 100%overdriven in short order pushing 15lbs of boost and all sorts of destruction would show up rapidly

Even with a 4-inch crank it's not going to be optimal with the 3.21 gear and that cam.

It will run good though and you can always add gear

Yeah i figured that while 3.91:1 gears may not be optimum for the 340 its still a very fun combination and i have thought about the option of doing a 416 instead and thought that maybe just maybe all that stroke would be able to pull the 3.21:1 gear nicely.

I'll take a different approach, and ask how and where will the car realistically be driven for the vast majority of the time? If it's going to see a lot of track time, then you really need to look into the technical side of things and determine what will be best for the ET slip you're chasing. The previous replies offer good advice in that regard.
But, you said it's a "fun" car, which to me implies that it will mostly be driven on the street with maybe only a few dragstrip passes once in a while. If that's the case, I'd go with the stroker. For stoplight to stoplight fun and the pure thrill of sticking your foot in it once in a while, nothing beats cubic inches. Having to rev the motor to the moon to go quick isn't as much fun on the street. Lots of low RPM torque, is!
Admittedly, I'm an "old guy" but I have seen many guys build cars that might be really good drag race cars, and then only take them to the track twice a year, but put on 4000 miles going to cruise nights and car shows. They end up with a car that's not as much fun to drive on the street, even though that's where the car actually spends the majority of it's time.
Be honest with yourself when making these decisions and in the end you'll end up with a car that's a blast to drive, plenty fast, and a joy to own.

In reality it will mostly be driven around town,to cruisenights,to other towns for carshows say maximum 150 miles or so one waytrips but thats the maximum and will be very rare,mostly within say 80miles or so,might go to a track a few times a year but this is mainly for driving on nice summerdays and stepping on the throttle from random stoplights.
Sort of trying to make the best out of the bunch of leftover parts from a previously expired engine,but i have heard so many good things about strokers that i have to ask

 

[1Fast340]

Yep!! If you don't know where you're going before you begin your journey you'll get lost and waste time (and money)....

Treblig

True words right there!
What makes me ask is that i already know where i am with the 340cube version of this with both gear ratios, and the 3.21:1gears with the 340 kind of works but is certainly not even remotely close to right,but it works nice with 3.91 gears and 26" tires.

The goal is a fun car that will rarely be raced. just a fun driver for nice summerdays with what most outside of the carhobby would call stupid power.

 

[Treblig]

True words right there!
What makes me ask is that i already know where i am with the 340cube version of this with both gear ratios, and the 3.21:1gears with the 340 kind of works but is certainly not even remotely close to right,but it works nice with 3.91 gears and 26" tires.

The goal is a fun car that will rarely be raced. just a fun driver for nice summerdays with what most outside of the carhobby would call stupid power.

Without an overdrive transmission your rear gear choices are fewer. If you only drive the car occasionally and never any long, long distances I'd go for the lower gear just for the fun of it!! But that just me??
That's why I went with the 2004R overdrive. 4:10/4:11 gears, tall tires and decent gas mileage.

Treblig

 

[rumblefish360]

Well, after reading that whole thing, the only off balance part of what I would do, the 400+ inch stroker and 800 Edelbrock carb, would be the cam choice with the 3.21 ratio.

It would be up to you to get the converter right with what ever tire diameter you choose. (I’d also use the widest tire possible) It would be an interesting balance between the two while your motoring down the Hwy. at what ever the rpm would be. I wouldn’t want the trans to get to hot because the converter isn’t engaging proper heating up the fluid.

While an external cooler would help a bunch, I would recommend that addition anyway to anyone on there Hwy. hot rod.

Staying tuned for this build.

 

[leblanc]

Still far from sure on where to go with my build and are mostly benchracing here,but here is something i have thought about.
What i have is a 73Duster With PB and PS (the last two things might change before this is done)

Weight last it ran was 3185lbs with me in it and a full tank of gas and a bunch of tools.
It does have subframeconnectors
904Transmission
32-3500RPM converter(i cant remember) its very nice and tight.
RPM Airgap manifold (also have a Edelbrock Tunnelram)
800cfm Edelbrock AVS or 750Proform mech secondary carb
Some very nicely ported Edelbrock RPM heads but still with the stock 2.02/1.60 valves
TTI 1 7/8" headers.
Comp XE 280R a small solidroller camshaft with 242/248 @.050" and .570/.576 lift

Here comes the real question the thing has a 8 1/4" suregrip rear with two available gear ratios.
I have a fresh bored 340 block that is .030" over with two fresh forged stock cranks just sitting and i also have a set of Eagle H-beam rods and would aim for about 10.5-11:1 or so compression on pumpgas.
Would you either build a:
stockstroke 340 with 3.91:1 gears
or a 416 4"stroker with 3:21 gears
With this bunch of parts?
Im sort of thinking that the difference in gear ratios would be equaled out so to speak by the gearing,except for idlequality that i dont find being much of a problem anyway.
For maximum performance the thing would obviously need more gearing with any of the options,but this is just fun car.



There are more options including a Lysholmtwinscrew and a E85 dominator but the options above are the ones that seems least stupid and wont eat blocks and drive line parts as often.

If I were you I would think hard of using a 360 motor, stroke it and add goodies, it would save you a bunch of cash.

 

[1Fast340]

Without an overdrive transmission your rear gear choices are fewer. If you only drive the car occasionally and never any long, long distances I'd go for the lower gear just for the fun of it!! But that just me??
That's why I went with the 2004R overdrive. 4:10/4:11 gears, tall tires and decent gas mileage.

Treblig

Yeah overdrive would be nice,but i already have a trans and a very nice converter,but who knows i might go that direction sometime in the future after this thing gets on the road again after a long wait in the dark.

Well, after reading that whole thing, the only off balance part of what I would do, the 400+ inch stroker and 800 Edelbrock carb, would be the cam choice with the 3.21 ratio.

It would be up to you to get the converter right with what ever tire diameter you choose. (I’d also use the widest tire possible) It would be an interesting balance between the two while your motoring down the Hwy. at what ever the rpm would be. I wouldn’t want the trans to get to hot because the converter isn’t engaging proper heating up the fluid.

While an external cooler would help a bunch, I would recommend that addition anyway to anyone on there Hwy. hot rod.

Staying tuned for this build.

yeah that cam is alitle large for that gear but would it be bad enough in a 416 to be worth swaping when i already have it and wont take the thing down the track that much?
Figuring it will roll on some 28" tall tires,probably some M&H or M/Ts with about 10" worth of section width from what i remeber would fit nicely in the stock wheelwells considering how hopeless it has been to get going on the rustrepairs on this thing im not going to start cutting up the wheelwells anytime soon. Lol.
Yeah external transmission cooler is a good idea even thought this custom converter is insanly tight when just driving around town,it has been between different engines and gear ratios in this car in the past without an external cooler without transproblems,dont laugh now but i used to run a radiator i found in a junkyard out of some 4cylinder Ford Escort or possibly a Sierra and used its built in automatic transmission cooler without any problems and the 340 never overheated and no transproblems either,but will avoid to take that chance again,since im probably to old to do the stuff i did when i was 25 again.

This build will happen over some time,there is lots to do but realy looking forward to get this thing on the road again hopefully to next summer.

 

[1Fast340]

If I were you I would think hard of using a 360 motor, stroke it and add goodies, it would save you a bunch of cash.

already have the fresh bored and decked 340 block,heads,cam,lifters,headers,intake,carbs,and pretty much everything needed for this except a complete rotating assembly(unless stock stroke then i just need pistons and a bunch of machinework+),oilpan and a bunch of bolts.Unless someone shows up and throws alot of money at me for that block.

 

[273]

Like you said both should be equally fast.
The 416 would be a better street engine.
340 probably a little more fun on the track.

416 has less down sides. Unless you like a radical small block while idling at lights.

Personally I go 340 3.31, or maybe 3.58 or 3.79 stroke.

 

[leblanc]

already have the fresh bored and decked 340 block,heads,cam,lifters,headers,intake,carbs,and pretty much everything needed for this except a complete rotating assembly(unless stock stroke then i just need pistons and a bunch of machinework+),oilpan and a bunch of bolts.Unless someone shows up and throws alot of money at me for that block.

318, 340 and 360 are all same block

 

[fishmens67]

500 horse 340 is a different animal. The gear ratio and converter choice is much too conservative for a 500 hp 340.
I'm thinking a stone is in the making.

 

[yellow rose]

318, 340 and 360 are all same block

No, they are not. Dimensionally they are, but you can't bore a 318 to standard 340 bore and you can't open the 273-318-340 mains up to 360 size, although why you'd want to do that I have no idea.

 

[Wyrmrider]

Are these the RPM heads with the .060 cut for piston clearance with out of the block 340 pistons?
get your quench down to the .035-.040 range (note I did not say .030 with the roller cam)
for saturday night build I'd go stroker (also easier to get compression) and keep whatever gears are already in it till you have to change for some reason
the stroker and the 340 will make about the same head dependent top end HP (340 at higher RPM) but the 400 will make more torque below peak HP- where you will driving it most of the time

 

[rumblefish360]

Like you said both should be equally fast.
The 416 would be a better street engine.
340 probably a little more fun on the track.

416 has less down sides. Unless you like a radical small block while idling at lights.

That’s kind of how I see it.

Personally I go 340 3.31, or maybe 3.58 or 3.79 stroke.

Wht! This again? Make up your mind! LMAO
I’m eye balling a 3.58 stroke for a 340 block I have hanging around, pending sonic checking.

 

[273]

That’s kind of how I see it.


Wht! This again? Make up your mind! LMAO
I’m eye balling a 3.58 stroke for a 340 block I have hanging around, pending sonic checking.

For me I'd never build a 4" stroke small block, To me bore stroke ratios and rod ratios still matter. Plus theres not to many good heads for 400 plus small blocks, thats why after peak hp numbers the curve takes a nose dive. I'd rather build a 383 or 400 than a 408-416.

So for me I'd go no bigger than a 3.79" stroke small block. If I wanted bigger than that I'd go stright to a 500-511 built from a 440.

But thats just me, I see why people build 408-416 and thats why I said he's probably better off building that.

 

[yellow rose]

For me I'd never build a 4" stroke small block, To me bore stroke ratios and rod ratios still matter. Plus theres not to many good heads for 400 plus small blocks, thats why after peak hp numbers the curve takes a nose dive. I'd rather build a 383 or 400 than a 408-416.

So for me I'd go no bigger than a 3.79" stroke small block. If I wanted bigger than that I'd go stright to a 500-511 built from a 440.

But thats just me, I see why people build 408-416 and thats why I said he's probably better off building that.

The 360 stroke is already taxing the limited cylinder heads. Anything more than that and you need to be looking at W-2 heads or better.

I wouldn't do another 4 inch stoke without W-2's. I wouldn't even do a 3.79 stoke without them.

 

[AJ/FormS]

Having driven an Eddie-headed 367 since 2004, with a 230* cam and 10.9Scr, as you can see I'm in no hurry to change it. It goes 93 in the 1/8' with no tuning and a 2.4+ 60ft; at 3467# wet and race ready, for the one and only successful run, it ever made . Fun as heck with a 4 speed and a 10.97 starter gear. That would be similar to a hi-comp 340 with a 2.45 low,that frisky TC, and probably 3.73s.
I also like it cuz it's a jump-in-and-go anywhere/anytime, almost zero maintenance, combo.
Whatever you decide,
Happy Hotrodding.

Oh;
At your 3185 weight, that 340 could be built with a smaller cam to rival the low-rpm performance of my 367 which is 3650 me in it, in street trim. As A streeter, I have run just about every gear from 2.76s to 4.88s behind that engine, and I can tell you that I think just enough gear to initiate tirespin is where I like to be; then let the torque do the rest. I'm not the rev-it up-and slip-it-out kindof guy, to get moving. Oh sure once underway I like to hear 7000 for 5 or 6 seconds, and then it's shut-down time cuz the 367 is probably speeding, and AJ don't get speeding tickets in this car, not since.... ever.

 

[1Fast340]

Like you said both should be equally fast.
The 416 would be a better street engine.
340 probably a little more fun on the track.

416 has less down sides. Unless you like a radical small block while idling at lights.

Personally I go 340 3.31, or maybe 3.58 or 3.79 stroke.

I do like a radical small block idling,but it would also be nice with a bunch of torque for a change, had it not been for a very good friends 383 chevy with the same cam and similar heads i would never have thought of building a stroker but that things was such a smokemachine that it kind of got to me.

318, 340 and 360 are all same block

Kind of almost,but i cant see the point in getting another block that needs the same machinework i already have done on the 340 block i already own,unless someone trows a substantial amount of money at me in exchange for the block i alredy own. A stroked 360 turns into a 408 and a 340 becomes a 416 so i fail to see the point here.

500 horse 340 is a different animal. The gear ratio and converter choice is much too conservative for a 500 hp 340.
I'm thinking a stone is in the making.

Would be alitle shy of 500hp,maybe 480 or so HP wich translates into an easy 500+ magazineHP so i put alitle shy of 500hp in there to make sure i confuse everyone. yes it will be under geared and less than optimum converter but trying to make something out of the junk i have.Leaning heavily towards stroker at this point,but i know for a fact that the 340 combo with 3.91:1 gears works quite nicely on the street even thought its probably terrible at a track with traction.

Are these the RPM heads with the .060 cut for piston clearance with out of the block 340 pistons?
get your quench down to the .035-.040 range (note I did not say .030 with the roller cam)
for saturday night build I'd go stroker (also easier to get compression) and keep whatever gears are already in it till you have to change for some reason
the stroker and the 340 will make about the same head dependent top end HP (340 at higher RPM) but the 400 will make more torque below peak HP- where you will driving it most of the time

Yep its a set of those 340 RPM heads,like said its leftovers that wont be perfect for anything but might become something fun.
With stock stroke some flattops and cuting the heads to closed chamber it would make pretty close to 11:1 compression.
With a strokercrank and flattops i would end up at 11.5:1 with no squish and that would most likely push me over the limit for pumpgas unless i go for E85 wish i prefer not to. 20 or so cc dishpistons and cutting the heads should get me right where i want to be with squish

For me I'd never build a 4" stroke small block, To me bore stroke ratios and rod ratios still matter. Plus theres not to many good heads for 400 plus small blocks, thats why after peak hp numbers the curve takes a nose dive. I'd rather build a 383 or 400 than a 408-416.

So for me I'd go no bigger than a 3.79" stroke small block. If I wanted bigger than that I'd go stright to a 500-511 built from a 440.

But thats just me, I see why people build 408-416 and thats why I said he's probably better off building that.

i see the bigblock idea,but i got way to much smallblock stuff collected and i wouldnt mind better heads,there are good heads on the market but well i only have the parts i have.

 

[1Fast340]

No, they are not. Dimensionally they are, but you can't bore a 318 to standard 340 bore and you can't open the 273-318-340 mains up to 360 size, although why you'd want to do that I have no idea.

See we can agree on something,i dont understand why i would want to buy a 360 either.

 

[273]

Both engines probably make around 1.15 lbs-ft per cid 345 = 397 lbs-ft and a 416 = 478 lbs-ft. Now times it by 1st gear and rear gear and you get. 345 cid, 2.45 x 3.91 x 397 = 3803 lbs-ft to the tires vs 416 cid, 2.45 x 3.21 x 478 = 3759 lbs-ft to the tires. You were right in the begining both combos would be similar.

 

[1Fast340]

Having driven an Eddie-headed 367 since 2004, with a 230* cam and 10.9Scr, as you can see I'm in no hurry to change it. It goes 93 in the 1/8' with no tuning and a 2.4+ 60ft; at 3467# wet and race ready, for the one and only successful run, it ever made . Fun as heck with a 4 speed and a 10.97 starter gear. That would be similar to a hi-comp 340 with a 2.45 low,that frisky TC, and probably 3.73s.
I also like it cuz it's a jump-in-and-go anywhere/anytime, almost zero maintenance, combo.
Whatever you decide,
Happy Hotrodding.

Oh;
At your 3185 weight, that 340 could be built with a smaller cam to rival the low-rpm performance of my 367 which is 3650 me in it, in street trim. As A streeter, I have run just about every gear from 2.76s to 4.88s behind that engine, and I can tell you that I think just enough gear to initiate tirespin is where I like to be; then let the torque do the rest. I'm not the rev-it up-and slip-it-out kindof guy, to get moving. Oh sure once underway I like to hear 7000 for 5 or 6 seconds, and then it's shut-down time cuz the 367 is probably speeding, and AJ don't get speeding tickets in this car, not since.... ever.

That is certainly worth considering,,i know what you mean with just enough gear,thats actualy a very good description how the old combo worked,it was just barely making fuzzy marks on the street if i stabbed the throtle from a standstill on a good stretch of road but would not break lose completely.

Both engines probably make around 1.15 lbs-ft per cid 345 = 397 lbs-ft and a 416 = 478 lbs-ft. Now times it by 1st gear and rear gear and you get. 345 cid, 2.45 x 3.91 x 397 = 3803 lbs-ft to the tires vs 416 cid, 2.45 x 3.21 x 478 = 3759 lbs-ft to the tires. You were right in the begining both combos would be similar.

That is some good calculations right there showing what i suspected, so i suspect the stroker with taller gears should be happier since the converter will be less wrong so to speak?