#'s Matching 340 build

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Hey Garrett, you do realize that pistons for this are a custom order since MP no longer carries parts for there discontinued line. 3.65 - 3.58 = a lot of stroke difference for a stock or even a replacement/performance piston. I guess you could have something made up if a regular slug did t fit. (Honestly, I would love to try just for fun. I love to tinker) While I think it is an excellent route to go, one I’m sure RAMM is up to performing, it would be the rest of the external parts package I would question and call questionable in it’s effectiveness with a 40 cubic inch increase. Below is a quote from the opening post;



This leaves just one question which I’m not 100% on, is the owner of this engine/car build making use of headers? Because at that point, I’d look into porting the heads really well. If I had to use the exhaust manifolds, that would change a thing or two.

Sr71mopar made a comment, “Kind I’d like a FAST build.”

If I decided to do a FAST engine, it would be for competition and nothing else, (believe me, I think about doing this for fun but on a lower non competition level) but because of the power limitations of a stock head and exhaust manifolds. This becomes less appealing. At least for something I’d like to drive and enjoy rather than street/track race.

While I think that 3.65" stroke crank is very appealing it's just not going to happen. The customer is not really interested in all out power nor is he interested in a $10k+ bill as we discussed. A FAST type build is not in the cards and I wouldn't recommend a large cubic inch stroker with X castings for a '69 Dart on a good day.

When exhaust limited as in this case--smaller cubes are your friend. A larger cube engine moves more air and fuel which means the already restrictive exhaust becomes MORE restrictive which drives the power curve DOWN. A 416 or actually a 418 in this case with X heads and stock exhaust manifolds without MAX effort everything will peak at a mind blowing (<sarcasm) 5000rpm--maybe lower.

I will try my best to work within the customers criteria. The criteria is always time, budget, reliabilty, output. In this case I have a surplus of leeway in time and output. What this means is the customer has given me an abundance of time and isn't all that concerned with output. It is paramount that the engine is reliable/driveable and within the budget. (on no greater than 91 octane)

Where I'm caught is I can't NOT try to make as much power as possible within the above parameters.

Most of the allure of a 340 powered '69 4 spd Dart is the high RPM a 340 willingly achieved. A 5000 MAX rpm 400+ cube 340 does not measure up here in IMHO.

So having said all that the engine will be tested with headers on the dyno so we will never really know the results with manifolds as installed in the car. However, the engine will be built to produce well over 300HP @ 5800 rpm or higher and meet all other criteria. It's a pretty tall order when you consider:

Can't throw compression at it
Can't throw an aftermarket intake on it
Can't throw a big cam at it
Can't throw good heads on it
Can't throw headers on it (in the car)
Can't throw a Holley on it (always better than a Carter)
Can't throw a stroker crank in it

What I CAN do is:

Perform the most accurate and relevant machine work within my abilities
Utilize modern internal engine components when feasible
Nail the valve timing events
Execute the right cylinder head work

I could and am already leaning on FABO for more ideas. Thanks, J.Rob
 
Oil & oil control?
Your take on gapless rings? Seems like sound logic, but I wonder about longevity, which for the owner would be an issue.
 
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@RAMM I was not suggesting you go that route, it just popped up in the convo.

Feel better!

And yet...... the fastest Mopar Wedges in FAST are all big cube combos.

The motor in the Duster in the pic...... the quickest of any SB FAST build(well into the 10’s)...... peaks well above 5k, and is only down 9hp 800rpm past peak.


I’m afraid anything I might offer won’t be of any help with Jesse’s plans, since my plan of attack would be the exact opposite of his.
I would absolutely positively be trying to steer the job towards using a 4” crank.
Yea, I just think that the car/engine owner is t ready to throw bags of money at this project but just allow Jesse to have a good time building up a power engine without getting wacky on it. The engine would still have to fit the budget and the cars driving parameters.

I think I missed the cars weight, gear ratio and tire size.
 
True, but the “Bags of Money” statement is on behalf of the cars owner and not knowing his wallet thickness, willingness to go big, etc...

From the owners point of view, it could be as simple as a thought process like... If the engine just needs a crank polishing/cutting and new slugs, is this cost effective to what I’m thinking vs. a 4 inch stroker?

I don’t know the mind set or desires of the owner. Or his knowledge base of what’s out there. He could be clueless or semi clued in. A good example of this are a few guys at work that know some stuff and think all stroker packages are a $2500 deal, then machining, then balancing, then assembled by the machinist...

We are into the hobby or in biz. Most of know better. He may not. So that’s where I got it from.

Never mind about the power return, which is cheaper to build?
Can sufficient power be made with the smaller CID?
(Clearly a personal and goal oriented view.)
Also a lot is what you can get away with.
The owner said make power. That’s a wide open field. The only thing I read otherwise which I maybe mistaken or assumed, was to stick with the 340. Which means to me, not a stroker. I don’t know? Am I wrong? Ehhhh, doesn’t really matter I guess. It’s just fun shooting the breeze on this.
 
Aluminum what? The mains are Federal Mogul MA series bored aluminum bearings which normally I really like. Is that what your question is? J.Rob

Oh yeah forgot--**** this virus!
Yes. Should have more specific. I'm working on that. :)
 
While I think that 3.65" stroke crank is very appealing it's just not going to happen. The customer is not really interested in all out power nor is he interested in a $10k+ bill as we discussed. A FAST type build is not in the cards and I wouldn't recommend a large cubic inch stroker with X castings for a '69 Dart on a good day.

When exhaust limited as in this case--smaller cubes are your friend. A larger cube engine moves more air and fuel which means the already restrictive exhaust becomes MORE restrictive which drives the power curve DOWN. A 416 or actually a 418 in this case with X heads and stock exhaust manifolds without MAX effort everything will peak at a mind blowing (<sarcasm) 5000rpm--maybe lower.

I will try my best to work within the customers criteria. The criteria is always time, budget, reliabilty, output. In this case I have a surplus of leeway in time and output. What this means is the customer has given me an abundance of time and isn't all that concerned with output. It is paramount that the engine is reliable/driveable and within the budget. (on no greater than 91 octane)

Where I'm caught is I can't NOT try to make as much power as possible within the above parameters.

Most of the allure of a 340 powered '69 4 spd Dart is the high RPM a 340 willingly achieved. A 5000 MAX rpm 400+ cube 340 does not measure up here in IMHO.

So having said all that the engine will be tested with headers on the dyno so we will never really know the results with manifolds as installed in the car. However, the engine will be built to produce well over 300HP @ 5800 rpm or higher and meet all other criteria. It's a pretty tall order when you consider:

Can't throw compression at it
Can't throw an aftermarket intake on it
Can't throw a big cam at it
Can't throw good heads on it
Can't throw headers on it (in the car)
Can't throw a Holley on it (always better than a Carter)
Can't throw a stroker crank in it

What I CAN do is:

Perform the most accurate and relevant machine work within my abilities
Utilize modern internal engine components when feasible
Nail the valve timing events
Execute the right cylinder head work

I could and am already leaning on FABO for more ideas. Thanks, J.Rob

Just port the heads and pick the cam that will assist in hurdling the exhaust manifold choke.
Intake matching and opening up the flange/plenum.

After reading many replies...it feels like some people are confusing your 2 threads, like this for the engine contest one.
You can be very streetable with a .500's lift cam or right around. Closing can be earlier with a roller and not sacrifice valve lift or trade off for more duration.
But not absolutely necessary just easier.

When comparing to some builds I've done and seen, you'll have no problem building 360-370hp in those parameters.
 
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Mopar official wrote in an above post
"closing the cam earlier with a roller"
maybe maybe not
here are pairs @.006 one is a Mopar FT with .006 above lash and the other is a HR
.006 .050 .200 w/1.6
280 234 155 576
280 238 *** 580

296 250 *** 580
296 250 170 584

300 242 161 .600
300 254 *** 628

304 245 163 .592 HR
304 253 173 .576 HR
306 253 172 .630 HR

*** no data
not for this thread but a .842 lobe FT can't be competitive with a 1.6 rocker
they would have to use the HR or higher ratio rockers
with mopar we have a choice
also not shown is that for higher lift the HR works better (on paper if they work at all)
 
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what are the old rod bearings and why so smoked? I like full grooved mains. extrude hone manifolds if they are a big restriction, maybe sneak 1968-70 units into the mix. why is a 750 holley better than a 750 Carter? if dialed in an engine does not Know the diff
 
The manifold choke at the outlet, that is tough.
I don't think 350 or so is hard with manifolds.
I built a 69 340 .040 very mildly ported x heads 245/189@.500 , stock iron 4 brl and exh manifolds and it did well with an isky .485 230@.050 108 in 4*adv iirr.. or some ****. 'He wanted to stay with his old cam' but it still went into mid 6500 rpm horse powered well for manifolds.
 
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i currently have 3 stock manifold vehicles with custom cams
440 with HP manifolds
350 chevy with rams horns in a pickup
250 chevy with through the prop exhaust (replaced 4 cyl Mercruser)
all have appropriately ported heads
the 6 cyl pulled strong to 6500 on the dyno and we chickened out 2bbl marine carb which is required
The 440 has no trouble with 6000 TQ Jones cam 2 series gears in a C body or in the motorhome
both have Isky dual springs
350 has no tach but runs great- has a TQ from a 360 altitude compensator etc
I also built a 383 Superbird stock looking with 440 crank and rods Crower 218 @.050 cam with .525 lift ported stock open chamber heads with 2.14 intake
My plan for the superbird was to max out the head flow at the lowest rpm possible through max rpm
It's a 4 speed and drives great on the street no problem with rpm drop problems, you can short shift it and just drive away from start or excess shifting required
The extra cu inches allowed us to back off on the compression and cam and still have a stronger build than building the 383 which could only max out the heads at higher rpm's
 
And yet...... the fastest Mopar Wedges in FAST are all big cube combos.

The motor in the Duster in the pic...... the quickest of any SB FAST build(well into the 10’s)...... peaks well above 5k, and is only down 9hp 800rpm past peak.


I’m afraid anything I might offer won’t be of any help with Jesse’s plans, since my plan of attack would be the exact opposite of his.
I would absolutely positively be trying to steer the job towards using a 4” crank.

Point me to where I said this was a FAST type build with a FAST type budget? Keep in mind I'm working on a budget in CDN funds which is roughly 35%-40% less than USD. And yet all of my hard parts come out of the US. See how this works Dwayne? J.Rob
 
@RAMM I was not suggesting you go that route, it just popped up in the convo.

Feel better!


Yea, I just think that the car/engine owner is t ready to throw bags of money at this project but just allow Jesse to have a good time building up a power engine without getting wacky on it. The engine would still have to fit the budget and the cars driving parameters.

I think I missed the cars weight, gear ratio and tire size.

You're right, the owner isn't willing to throw bags of money at this project--Just want to keep it simple and preserve the originality of the car. Car is a '69 4spd Dart with 3.23 gears. J.Rob
 
Bags of money?

It’s getting pistons anyway, and needs the crank reground at a minimum....... so it looks like the bags of money would be the difference in cost between fixing the stock crank and buying a new one, and a set of rods.

Jesse has mentioned numerous times in other posts that he’s not a fan of the 4” crank with std type heads.
Which is fine...... it’s his build to sort out.
But the reason for not stroking it isn’t really the cost.
If he were an advocate for the 4” stroke, I have no doubt he could have convinced the customer that an extra 70 cubes for a few hundred bucks was worthwhile.

Yes it will take approx 3 bags of money in CDN to do what you would--I only have 1 bag of CDN money to work with. Capiche?

I am NOT a fan of the 4" crank ESPECIALLY with stock heads, stock exhaust manifolds, etc... You must like the way a Cummins diesel drives--myself, I hate the way diesel power is delivered, unless I'm pulling something.

The reason for not stroking IS in large part COST because I can't charge for a ton of head work, and for me to turn the crank is less than half of a Scat 9000 series cast crank--If I move to a forged crank the disparity is even worse!

I'll tell you what --I'm about to get the customer to chime in here so he can either commission me to build him a 418 because you have convinced him otherwise. I will build him anything he wants but when speaking with him, I was not led to believe he wanted anything to do with a 4" crank build.

I would like to ask you-- Mr. Porter a question.

What would your bill look like to build this 340 into a 418? Truly I'd like to know--maybe I'm charging incorrectly. Oh and shop rate is $95.00/hr.

After you answer this I will share what the client and I discussed for budget. J.Rob
 
Just port the heads and pick the cam that will assist in hurdling the exhaust manifold choke.
Intake matching and opening up the flange/plenum.

After reading many replies...it feels like some people are confusing your 2 threads, like this for the engine contest one.
You can be very streetable with a .500's lift cam or right around. Closing can be earlier with a roller and not sacrifice valve lift or trade off for more duration.
But not absolutely necessary just easier.

When comparing to some builds I've done and seen, you'll have no problem building 360-370hp in those parameters.

This is one of your better replies--thankyou. I too believe some people are confusing things. I think this virus **** is getting to some more than others. I understand about a roller but that ain't in the cards. J.Rob
 
"closing the cam earlier with a roller"
maybe maybe not
here are pairs @.006 one is a Mopar FT with .006 above lash and the other is a HR
.006 .050 .200 w/1.6
280 234 155 576
280 238 *** 580

296 250 *** 580
296 250 170 584

300 242 161 .600
300 254 *** 628

304 245 163 .592 HR
304 253 173 .576 HR
306 253 172 .630 HR

*** no data
not for this thread but a .842 lobe FT can't be competitive with a 1.6 rocker
they would have to use the HR or higher ratio rockers
with mopar we have a choice
also not shown is that for higher lift the HR works better (on paper if they work at all)

While i appreciate your input Wymrider, I am not going down the roller cam road at all here. Thanks for chiming in though. J.Rob
 
The manifold choke at the outlet, that is tough.
I don't think 325 or so is hard with manifolds.
I built a 69 340 .040 very mildly ported x heads 245/189@.500 , stock iron 4 brl and exh manifolds and it did well with an isky .485 230@.050 108 in 4*adv iirr.. or some ****. 'He wanted to stay with his old cam' but it still went into mid 6500 rpm horse powered well for manifolds.

6500rpm is way higher than I have seen with manifolds but.... different builds. How high would you expect that build at 418 cubes to peak? Asking for a friend. J.Rob
 
what are the old rod bearings and why so smoked? I like full grooved mains. extrude hone manifolds if they are a big restriction, maybe sneak 1968-70 units into the mix. why is a 750 holley better than a 750 Carter? if dialed in an engine does not Know the diff

Not sure why the rods are so smoked just yet. (Haven't measured much just yet) Experience tells me that a Holley is just about 15hp better than an equivalent Carter. Trust me I've done this comparison many many times. The Holley is just a better fuel mixer--it isn't about quantity here its about quality. J.Rob
 
350 has no tach but runs great- has a TQ from a 360 altitude compensator etc Love those carbs--the Alt compensator can be used for performance if you know how
I also built a 383 Superbird stock looking with 440 crank and rods Crower 218 @.050 cam with .525 lift ported stock open chamber heads with 2.14 intake

218 @ .050 with .525" lift? Thats a fast cam dude. J.Rob
 
You're right, the owner isn't willing to throw bags of money at this project--Just want to keep it simple and preserve the originality of the car. Car is a '69 4spd Dart with 3.23 gears. J.Rob

Ahhhhh, there we go! Thanks. Just the information I was looking for. As well as the key words, reasonable cost, using the “KISS” method, out a little excitement in it. 3.2:’s and a 4spd. Very nice. Driver drive train. I suppose tires aren’t very big then? Stock or slightly over sized.

When I was still working in my garage for customers & the order came in with these parameters, there would be just a few questions I’d need to ask. (I loved these chats with people when they new what they wanted.)

What kind of power increase are you thinking of?
At what RPM are you cruising at?
Are you looking for “That Muscle Car sound?” Or a smooth idle?

I’m not sure what you’ll do for a cams duration. With stock heads with a nice valve job, the cam will not have to be to large for a nice return on power and have great driving attributes.
 
6500rpm is way higher than I have seen with manifolds but.... different builds. How high would you expect that build at 418 cubes to peak? Asking for a friend. J.Rob
That cam advertises 300 duration and he was a hair light on gear at 3.55 but you can stretch rpms with an auto in 2nd. lol
That combo, identical, with the exception of 4" stroke...probably about 5600 and done, no more hp...tapped.
I ported those in the bowl, did not do any guide work or roof kink...just a gasket match and bowl work. It was like you're doing...on a tight budget.
I just wanted an honest 350-65hp for him and I didn't think the cam on stock x heads would do it alone.
What the others don't realize is that you can get a production head to flow pretty decent ..like close to/about 250cfm without ever touching the guide, roof kink, without gasket matching or back cutting...works great on a 340-367cid ,but it's still a small port volume for 408+.You can remove the kink, do the guide profile, gasket match....nothing else ...and only find maybe 10-12 cfm, but the volume gain can open the window rpm wider. Volume is how how the rpm window is, smaller is lower...bigger is higher. Stock 155-160cc heads need to be a minimum of 15 cc bigger to make it into the 6000 rpm playground with a 4" stroke.


For everybody else ...
a good example is a 340 built with ported 273 heads, 188 intake valves, a .470 lift solid cam with 223 at 50 on a 110, with .029 quench distance
That engine , although making more power than a stock 340, was done around 5500ish rpm...like horse powered out, breathless.
305hp @5400 375lbs@3800-4000rpm
The heads had a final port come of about 137cc, that is too small for 340cid, 145 is too...that's why a stock j or x will support 6800 rpm and a 675/315 273/318 head flowing the same and actually a hair better on a 340/360cid is a rpm limiter/choke because the volume is short for the cid.
Port volume IS important.
If you want a factory head to support 4" stroke, you will have to spend a lot of time simply making the port bigger, walls, roof, guides...'bowl' most dont have the money to pay for it...or the time. I wouldnt pop heads out like this in a week, or 2 or 3, more like.. I'll call you when they are done. Labor of love or a sadists dream come true. Lol
 
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