Stroked Supercoupe

cheeriosluvr

Registered User
I had no intensions of even thinking about this due to the problem of breaking the 4.2L crankshaft that they use. Well i have found a company that we sell that makes Billet V6 crankshafts...so now that i can get a crankshaft what do the do for pistons and rods???

if anyone can help me out with what the do to the pistons and rods please let me know.

Todd
 
Todd,

Do you mind telling me what one of the billet stroker crankshafts costs? I've thought about this and decided not to for the same reason. I can't afford the $2500 USD crank that Fred had custom ground (I think that's what I heard it cost him).

Cheers,

Sean
 
351W rods with custom order pistons!

351W rods have the same crank journal size (well, they are 0.0005 bigger, more room for oiling) and the piston pin bore is also the same size. There are TONS of aftermarket 351W rods avalible. You would need to order Custom pistons with slightly less compression hight as the 351W rods are slightly longer.

here is the specs
89-95 SC rods 5.9135"
351W rods are 5.956" long
SO 351W rods are .0425" longer
Longer rods = Better rod ratio, and less piston side loading
You will need custom piston pin to deck height anyhow for a stroker engine so just make sure to take the .0425" into account
 
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In case you don't already know this. There is a living 4.3 owned by Dr Fred H..aka..."Fred4.3" He lives in Colo where I'm located. We are friends and I highly suggest you take the advice from someone whos done it. It can be quite problematic. For one when stroking an SC you cause the Knock sensor to become virtually inoperateable sinnce the freqency is changed, but I'll let you get the details from the true and only Stroked SC owner
e-mail him, ...fredholz@concentric.net

or jump over to thw SCCOSW atwww.sccoa.com/forums/newreply.php?action=newreply&threadid=7550
 
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The knock sensor not working goes without saying...As far as stroking a 3.8..I seriously dont see there being such a problem if thats what you want to do..Of course there will be custom parts involved...Its all a matter of money...However I do remember seeing in a post that the motor has been revved to 7000..Normally at least with my smallblock ford experience I build a stroker motor so I can make more power downstairs...Revving stroker motors tend to blow up all sorts of nice things..Rods through side of block (if your lucky), Broken cranks..This is due to the nature of a motor with a longer rod. You can make any motor Rev..Doesnt mean it should:O)..Other things to look out for is ring location on your custom pistons..Many stroker motors like to eat up rings because of poor location,,There is actually alot of trial and error involved as well as engineering..SO to build a stroker motor is easy..To build one that lasts..Well thats another story..Finding the perfect rod ration..The perfect Pin location (has alot to do with where your rings end up)..The perfect stroke (has alot to do where your Pin ends up)...You can make it all fit,,But will it last....And keep in mind...If you want to rev a motor..The way to go is less stroke less rod lenght:O)..Night
 
Yeah the billet crank runs around $1500USD. Its the strongest material out there made by a excellant company SCAT Racing.
I got 351W rods in stock and i may be able to get custom pistons from Manley or JE. I know manley will custom make some pistons but they will cost around 600+

Todd
 
351w rods

I've built a couple of 351s and I remember the rods you want are from the truck motor. They have a football shaped head on the rod bolt with chamfers around it. The square head rod bolts dont allow the rod to chamfer around it and therefore they are not as strong.
 
Are you telling me that SCAT is making or can make a billet crank for the 3.8 for $1500? Is this a custom one off piece? How did you talk them into doing this?
 
Well, I didnt talk them into doing it...it something new they do. All Domestic and Imports V6 Billet crank shafts, they will make it 1 or 2 peice rear main seal, odd or even fire. If you want an exact price quote email me with what you want and ill get you a price. We sell SCAT cranks and SCAT stroker kits for Ford and chevy V8's.

Todd
 
Wow. That's pretty neat. Maybe I'll have to start saving up for that. So basically any kind of custom billet V6 crank you want for $1500?
 
I just spoke to SCAT about 2 weeks ago, and they said they would make a 3.8 crank on these conditions:

Minimum 10 cranks, at $3000 each. Since Moldex will make them for $2150 each, and you only need to buy one, I went with them. Tell me who to call to get this $1500 deal, because SCAT says go to hell. :)

Also, can you give us some details, such as the metal used, and heat treatment, as well as any coatings done after the heat treatment?

Chris
 
First you need to have an understanding on who we are....we are one of the biggest SCAT distrubtor in the northeast. You have to know people to get hooked up with the right deals.

Its availible in a variety of materials, Ion Nitride Hardening, Superlight counterweights availible, one or two piece rear main seal.....thats just out of there catalog

If you want more i will have to have to call on monday

Todd
 
Please get ALL of the details ASAP. If you can in fact make a Billet 4340 crank heat treated properly and nitride hardening for $1500, you might have your first customer, but you need to get me info NOW because the one I already ordered will be getting made VERY soon.
 
Nobody ever said that 7000 was intentional. Thank the AOD and Transgo for that BS. But it got there and came back okay. The strokers come out a lot lighter in the reciprocating mass, and therefore are predisposed to want to rev (counter intuitive, isn't it?). Revving a stroker is not a problem up here in the clouds, as long a piston speed is not an issue, and it's the only way to get anywhere in a NA street mill.

I settled on my crank supplier because I wasn't about to do this over, again, and they made the crank in the national record holding V6 in a GN. As it was the first for them on this engine, I had to pay a bit more than usual, to support the R & D of it.

If it can be done for $1500, then more power to ya !
 
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Fred,

Did you get that stroker crank in that motor yet? Are you going to Kansas? I want to see that thing run! Whitey would be curious to see how it runs too. He asked about you last time I spoke to him.

Chris
 
Best bet for you guys would be to put together a kit..Crank rods pistons...Of course peopel like me would be looking at any longevity issues:"O)~....
 
As you had begun the discourse, there are many issues. One of them is the stoke is limited if you want room for a stud girdle. Yes, you need one !
 
I've been told by some web sites that you can put a 4.2 crank and rods in the 3.8 to produce a 4.2 because the 4.2 is the same block as the 3.8.

ive been tryingto get more info on this since i have to rebuild my bottom end on my 3.8.

is this true i have a 91 3.8 is this something i can do to my 3.8 or is it only for the 97 and up 3.8's?And what els is involved?I asumed that the pistons where the same size. any info would help thanks

PEACE
 
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