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383 stroker ???

Posted: Sun Nov 06, 2011 11:03 pm
by corvettekiller666
i have a 350,2 bolt main, that i want to stroke out to a 383.
ive heard the whole 2 vs. 4 bolt discussion and im not worried about that. what i am worried about is the crankshaft! im not wanting to build a power crazy,tire eating monster i just want a little more torque for my truck. would a cast crank be okay since im not revving past 5500 RPM ? and what would my power be like with the 76 cc heads i have on it now? any help would be appreciated greatly. and im 18 so budget is somewhat of an issue...

Re: 383 stroker ???

Posted: Mon Nov 07, 2011 8:28 am
by sc racing
corvettekiller666 wrote:i have a 350,2 bolt main, that i want to stroke out to a 383.
ive heard the whole 2 vs. 4 bolt discussion and im not worried about that. what i am worried about is the crankshaft! im not wanting to build a power crazy,tire eating monster i just want a little more torque for my truck. would a cast crank be okay since im not revving past 5500 RPM ? and what would my power be like with the 76 cc heads i have on it now? any help would be appreciated greatly. and im 18 so budget is somewhat of an issue...
I see no problem with that at all we ran a gm cast crank in out 355 with 12.5:1 compression and it had been 7000 rpm. I would think a good aftermarket cast steel crank is better than a gm cast iron one.Im not sure what heads you have but the longer stroke should improve torque.

Re: 383 stroker ???

Posted: Mon Nov 07, 2011 1:01 pm
by corvettekiller666
[/quote]
I see no problem with that at all we ran a gm cast crank in out 355 with 12.5:1 compression and it had been 7000 rpm. I would think a good aftermarket cast steel crank is better than a gm cast iron one.Im not sure what heads you have but the longer stroke should improve torque.[/quote]
The casting number is 3998993 and i looked it up and its a 76cc cast iron head. i got the engine and transmission from a 1974 gmc sprint(el camino).

Re: 383 stroker ???

Posted: Mon Nov 07, 2011 4:49 pm
by sc racing
The heads are going to be the "bad" part in the engine but you can always upgrade later or look for a good used set,it might not cost a lot more if you were planning to rebuild the ones you have now.

Re: 383 stroker ???

Posted: Mon Nov 07, 2011 10:31 pm
by spib
I have a 355 thats all stock except 470 lift elgin cam
its 10 yrs old and has been ran hard from day one
went 12.38 in my blazer and has been 13.71 in wifes 4,000lb
67c10
you will be fine

Re: 383 stroker ???

Posted: Sun Nov 13, 2011 1:28 am
by corvettekiller666
sc racing wrote:The heads are going to be the "bad" part in the engine but you can always upgrade later or look for a good used set,it might not cost a lot more if you were planning to rebuild the ones you have now.
What do you mean "bad"? Is there something wrong with the ones i have now?

Re: 383 stroker ???

Posted: Sun Nov 13, 2011 9:01 am
by sc racing
corvettekiller666 wrote:
sc racing wrote:The heads are going to be the "bad" part in the engine but you can always upgrade later or look for a good used set,it might not cost a lot more if you were planning to rebuild the ones you have now.
What do you mean "bad"? Is there something wrong with the ones i have now?
I just mean they are not the best for making good power they are just 1974 stock heads which were not designed for making high horsepower that was the era of emmisions and fuel milage not power. If your going to spend money rebuilding them your better off spending the money on better heads. Just my opinion.

Re: 383 stroker ???

Posted: Tue Nov 15, 2011 1:20 am
by corvettekiller666
I just mean they are not the best for making good power they are just 1974 stock heads which were not designed for making high horsepower that was the era of emmisions and fuel milage not power. If your going to spend money rebuilding them your better off spending the money on better heads. Just my opinion.[/quote]
what like aluminum heads or just something with bigger ports or a smaller combustion chamber?

Re: 383 stroker ???

Posted: Tue Nov 15, 2011 8:04 am
by sc racing
There are a lot of better heads available older castings like 461,462,even 441 or 882 are probably better but being old they will need to be redone. I dont know what your budget is so I really cant recommend a head because you can easily spend $1000-$2000 on a set.The chevy vortech head is a good budget head but you will need a special intake to bolt to those heads. There are way to many options.Maybe your local engine shop has a set already done that a customer gave up on and you can get a deal.

Re: 383 stroker ???

Posted: Sat Nov 19, 2011 2:43 am
by corvettekiller666
sc racing wrote:There are a lot of better heads available older castings like 461,462,even 441 or 882 are probably better but being old they will need to be redone. I dont know what your budget is so I really cant recommend a head because you can easily spend $1000-$2000 on a set.The chevy vortech head is a good budget head but you will need a special intake to bolt to those heads. There are way to many options.Maybe your local engine shop has a set already done that a customer gave up on and you can get a deal.
well right now i have 76$ to my name because some thing came up but i dont really want to put more than 4 grand into the engine. like i said i dont want a race engine,i want a truck engine.i want to keep in carburated but upgrade to a four barrel and those intakes for the vortec heads that use a carb are too expensive for my blood. out of the heads you mentioned what do you think would help me get more torque?

Re: 383 stroker ???

Posted: Sat Nov 19, 2011 8:51 am
by sc racing
I would try to find 441 or 882 heads they have accessory holes in them and would be easier and cheaper to get and the old style intake will bolt on you can usually find a used intake at a swap meet for $50-$75.Good luck

Re: 383 stroker ???

Posted: Sun Nov 20, 2011 3:40 am
by corvettekiller666
that opens up a few possibilities! ill have to go around and start checking for some of those vortec heads. thanks a ton!

Re: 383 stroker ???

Posted: Sat Nov 26, 2011 8:51 pm
by Outlaw2
I bought a set of 092 vortec heads 64cc for $300. Intake for it is $187. U can buy a complete kit thru national auto parts. I'm gonna run a 750 Carb w/ 284 or 292 cam, and i'm on a low budget build also!! Go to hotrod mag, they have an artical junk yard build. Low budget build under $2000. :attack:

Re: 383 stroker ???

Posted: Mon Nov 28, 2011 6:09 am
by corvettekiller666
Outlaw2 wrote:I bought a set of 092 vortec heads 64cc for $300. Intake for it is $187. U can buy a complete kit thru national auto parts. I'm gonna run a 750 Carb w/ 284 or 292 cam, and i'm on a low budget build also!! Go to hotrod mag, they have an artical junk yard build. Low budget build under $2000. :attack:
thats awesome! thanks!

Re: 383 stroker ???

Posted: Fri Jul 27, 2018 8:30 am
by Lequye
Just my two cents for the old thread...
If building one with the standard 4.000" bore 5.7L block, you end up with 377 cu in (6.2L ).
If you go with a .030'' over-bore 5.7L block, you end up with 383 cu in (6.3L ).
There's 33 more cu in of displacement with this engine due to the .270" longer crankshaft stroke.
(GM's 6.6L (aka 400 cu in) stroke is 3.750" ....... 5.7L stroke is 3.480")

The main journals must be turned down in order to fit the 5.7L block.
The rod caps do need to be modified for clearance as does the 5.7L block in certain areas.


With the stroker kits that you can buy, you'll likely get components that are suited for the auto guys.
If you don't specify, very likely you'll get the full dished pistons , of which I'd not wish on anyone for a SBC.

While the full dished pistons do bring the C/R into a correct range, these cannot possibly create a quench or squish within the combustion chamber. The quench or squish is important for a Marine build, and especially important for a mild stroker for Marine cruiser use.

I don't want to discourage you from making a 383 https://mechanicguides.com/best-383-stroker-kit/ but you should know some of the problems that you will run into. The bore size and the crank are seperate issues. have the block cleaned and checked for cracks first,have it bored to the minimum oversize, then you'll probably have to get it align bored ( straightening the crank bearing bores,since you didn't mark the location of the bearing caps,) the machinist will tell you what sizes he went to, so then you can order your rotating assembly. I recommend buying a balanced assembly. You will then have to grind the block for rod bolt clearences in the bottom of the block, just enough to get 0.050 gap, careful here cause there's a water jacket there. The only other issue is the rod bolts hitting the cam,a small base circle cam will fix that problem. Good Luck