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383: Why stroke to 438 vs. 496?

HawkRod

Formerly hsorman
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A question for the extremely knowledgable forum! :notworthy:

When I eventually rebuild my now stock 1970 335HP 383, I would like to stroke the engine. If you go to 440 Source, for example, there are two stroker kits for the 383. One strokes it to 438 cubes and the other strokes it to 496. Both kits cost the same, and both have approximately the same installation.

So my question is - Why would you ever buy the 438 stroker kit???

I understand the benefits of the 496 in that you get more power and torque. It seems to me that there must be some advantages to the 438, or they wouldn't offer it?!? Does it have some better characteristics? Revs higher? More reliable?

Any thoughts you have would be appreciated!
 
The potential issue with a big big stroker is durability. Many many years with many many miles doable??? Can it see 80/90 thousand without issue? People worry about the side wall loading. Rocking pistons, because there short.

Maybe it's a little lie ... "I have a 440 ... lo-deck ..."

A 472 is also another excellent CID to stroke to. All the bennies of a bigger stroker and cubes that work great with ported heads without a big cost of the bigger flowing heads. Of course, to day, that issue is going grey. With the selection of heads available. Yester-year, the head selection wasn't like it is today. Yester-year, there was, Indy, MP's Stage VI, (which should work really well at that CID.) Who else? OH, Brodix. Who else though.
 
If your going with a stroker crank why not spend a little more and get one from eagle-
Idk if I trust 440 source-to be honest
 
The 438 may be less work as you may not have to clearence the block. My 4.15 crank cleared in my 440 block and was only close to the oil pump passage. But at the same price I would go with the cubes as I love my 493. My brother and I have both used the 440source cranks and they have been fine. And we checked the cranks before we used them. Ron
 
The 438 may be less work as you may not have to clearence the block. My 4.15 crank cleared in my 440 block and was only close to the oil pump passage. But at the same price I would go with the cubes as I love my 493. My brother and I have both used the 440source cranks and they have been fine. And we checked the cranks before we used them. Ron

The block clearance is an issue with the 496. A lot more machine work is going to be required to make everything clear. So the cost goes up considerably unless of course you are a machinist or know one willing to do the work. It is so much of an issue in fact, my engine builder said he would never offer a 496 again because the work involved was just to extensive. Well, that's not entirely true...he would offer it but said if you want it you are going to pay for it but the price for it would be cost prohibitive for any potential buyer.

That said, I have been very please with the power and durability of my 496 so far.

Below are some specifics:

Eddy RPM heads
850 quickfuel carb
10.5 compression
Comp cam XR292R-10 (Solid roller)
Intake lift .582 Exhaust lift .588
Intake duration @ .050 Intake 254 Ehaust 260
Eddy dual plane intake (Chose for more torque and clearance issues vs RPM)
Comp Cams 1.5 Ultra Pro Magnum Shaft Mount Roller Rocker Arms
Crower Severy Duty HIPPO solid roller lifters(high pressure pin oiling)
Diamond forged flat top pistons

Dyno numbers:

RPM tq (ft-lbs) HP
3500 580 386
3600 582 399
3700 601 423
3800 611 442
3900 610 453
4000 605 461
4100 608 474
4200 603 483
4300 605 496
4400 609 510
4500 603 517
4600 599 525
4700 597 535
4800 588 537
4900 586 546
5000 576 548
5100 571 555
5200 542 546
5300 535 540
5400 527 542
5500 511 535
5600 511 545
5700 502 545
5800 493 544
5900 474 532
6000 459 513

Here is a video where you can hear it running on the street.

http://www.youtube.com/watch?v=a3HMxiTl5JU


4000k miles on it, no issues.
 
70rr_Brian: It is interesting that you said that there was a lot of machine work to make everything clear in your 383 based 496.


According to 440 Source for their 496 based 383: "The low deck, 4.250" stroke version of our Platinum Series crank used in this kit has the smaller 2.200" (big block Chevy sized) journals, and the counterweights are finished at the smaller "B" engine size, to ensure they will drop right into the block with no counterweight clearancing issues. Depending on the block used, many of customers find this kit drops right in with no modifications whatsoever!"

Is this similar to what you used?

To all others - thanks for the replies! It seems the biggest potential downside may be longevity, once any clearancing issues are addressed.
 
"Depending on the block used, many of customers find this kit drops right in with no modifications whatsoever!"

Perhaps that is the key operative phase in that sales pitch. It is a 1969 cast date block. All I can tell you is he said the block had to be cut extensively for rod clearance.

This was not a kit but rather pieced together. I would have to look at the exact parts list. But I can tell you the only thing in the motor from 440 source was the billet rear main seal cap and the valley pan hold downs.

Would have to do some digging to get the exact specs on everything.
 
Perhaps that is the key operative phase in that sales pitch. It is a 1969 cast date block. All I can tell you is he said the block had to be cut extensively for rod clearance.

This was not a kit but rather pieced together. I would have to look at the exact parts list. But I can tell you the only thing in the motor from 440 source was the billet rear main seal cap and the valley pan hold downs.

Brian,

Perhaps it is the way the counterweights are designed, or they have a lot of latitude in their sales pitch!!! Either way, thanks for the details - I have some time before I have to decide anything anyway.
Also, I am not sold on 440 Source either - I just happened on their web site and was trying to get some comments on the pros and cons of stroking bigger vs. smaller. I seem to hear very polarizing comments about 440 Source. Either people seem to be very happy or they say it's junk. Who knows?

By the way, your video is AWESOME!:headbang: That's the way a motor is supposed to run! I like the way your motor was built in that it seems very drivable, yet can pour on the power when needed. Since I will spend most of my time on the streets, I would much rather have a motor like yours with a broad flat torque curve and decent road manners.
 
The block clearance is an issue with the 496. A lot more machine work is going to be required to make everything clear. So the cost goes up considerably unless of course you are a machinist or know one willing to do the work. It is so much of an issue in fact, my engine builder said he would never offer a 496 again because the work involved was just to extensive. Well, that's not entirely true...he would offer it but said if you want it you are going to pay for it but the price for it would be cost prohibitive for any potential buyer.

That said, I have been very please with the power and durability of my 496 so far.

Below are some specifics:

Eddy RPM heads
850 quickfuel carb
10.5 compression
Comp cam XR292R-10 (Solid roller)
Intake lift .582 Exhaust lift .588
Intake duration @ .050 Intake 254 Ehaust 260
Eddy dual plane intake (Chose for more torque and clearance issues vs RPM)
Comp Cams 1.5 Ultra Pro Magnum Shaft Mount Roller Rocker Arms
Crower Severy Duty HIPPO solid roller lifters(high pressure pin oiling)
Diamond forged flat top pistons

Dyno numbers:

RPM tq (ft-lbs) HP
3500 580 386
3600 582 399
3700 601 423
3800 611 442
3900 610 453
4000 605 461
4100 608 474
4200 603 483
4300 605 496
4400 609 510
4500 603 517
4600 599 525
4700 597 535
4800 588 537
4900 586 546
5000 576 548
5100 571 555
5200 542 546
5300 535 540
5400 527 542
5500 511 535
5600 511 545
5700 502 545
5800 493 544
5900 474 532
6000 459 513

Here is a video where you can hear it running on the street.




4000k miles on it, no issues.



Well my 493 is an RB block and as I said everything cleared and it uses the Mopar rod journal sizes not the smaller chevy size. But I am sure the low deck has less room. I cant say much for a 496 using a 383 block but there are tons of 499's and 512's out there built from the 400 block that dont need a bunch of machine work for clearance. I am not aware of the 383 being much different then the 400 block other then bore and the 400 is stronger in the main webbing. My brother runs a few 400 strokers of the 499 and 512 sizes using 400 blocks and they did not need much clearance if any. But they are usually the smaller chevy size 2.200 rod journal size where maybe yours was not ? Ron
 
I would not consider a stroker kit for a big block mopar, 383,400, or 440, that didn't use big block Chevy rods. Lighter pins, lighter pistons, any quality rods you care to buy, more room for stroke increase with less block grinding, lighter rods, all of which contributes to longevity and power.
Final displacement around 470 seems to be a sweet spot, but I wouldn't be afraid of a 496 in a 383 block. The bore and stroke combo of a 496 mopar is EXACTLY the same as a typical big block Chevy 454 stroker combo that is very highly regarded, with thousands of them running around.
Edit. The reason 383s weren't typically stroked in the old days was because of the extensive machine work necessary to put a 440 crank in, and then net only about the same cubes (actually slightly less) as a stock 440. Now that there are dedicated strokers for the low deck motors, there is little reason NOT to stroke one. There are a lot more pistons available for stroked low deck motors than stockers. Tried to buy forged pistons for stock stroke 383/400 lately?
 
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I have a 383 stroker 496 in my car, had it over 5 years! Used and abused! Extremely reliable, and required no machine work, I bought My kit from muscle motors, just did oiling mods, don't be afraid to use this kit.
 
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