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Discussion Starter · #1 ·
hi guys:)

building my first 383 stroker having trouble picking the pistons and cam to go with everything. Building it to run a weiand 6-71. trying to keep compression below 9:1 before the blower. *trying* to avoid race gas territory although I would be ok with a high octane race fuel car.

Here's what I have so far:

350 block .030 over
Scat 435056 forged 4340 crank
AFR 1038 75cc heads
MS909HK main bearings
CB663HNK rod bearings

I would like a real lumpy cam, the heads can go up to 0.600 in. lift

oh and here's where the engine is going :cool:

 

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good info about the cam!thanks

looking at these pistons, what do you guys think ?

Wiseco K0067A3, Wiseco Domestic Automotive Forged Pistons | Wiseco

I don't think that 29CC dome is going to work well with a pump gas blown engine.
While Wisco makes a very nice piston you might take a look at something more like this:
http://www.summitracing.com/parts/pbp-12334-030

You have not stated what length rod your planning on using so be sure you get a piston that will work with which ever rod you decide to run.


The above piston should get you in the 9:1 CR. You may wish to go with a D shaped dish piston to get a bit lower in the CR department.


http://www.summitracing.com/parts/pbp-12343-030


Go with a hyd roller cam.
Keep the LC at 112-114*.
Duration at .050 in the 225-240* range. How much stall torque converter are you planning on running?


Good luck with your build
 

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Discussion Starter · #5 ·
I don't think that 29CC dome is going to work well with a pump gas blown engine.
While Wisco makes a very nice piston you might take a look at something more like this:
http://www.summitracing.com/parts/pbp-12334-030

You have not stated what length rod your planning on using so be sure you get a piston that will work with which ever rod you decide to run.


The above piston should get you in the 9:1 CR. You may wish to go with a D shaped dish piston to get a bit lower in the CR department.


http://www.summitracing.com/parts/pbp-12343-030


Go with a hyd roller cam.
Keep the LC at 112-114*.
Duration at .050 in the 225-240* range. How much stall torque converter are you planning on running?


Good luck with your build
thanks

its a 6" rod and for the amount ill be driving it race gas is fine unless it's unsafe for the street or something. but thanks ill check out the other pistons.

as for the torque converter i haven't even studied that yet lol

basically im a blank slate, tell me what you would do? ;)

and im hoping to hit 475hp - maybe 650hp at the most (and I have absolutely no idea how realistic those expectations are lol )
 

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hi guys:)

building my first 383 stroker having trouble picking the pistons and cam to go with everything. Building it to run a weiand 6-71. trying to keep compression below 9:1 before the blower. *trying* to avoid race gas territory although I would be ok with a high octane race fuel car.

Here's what I have so far:

350 block .030 over
Scat 435056 forged 4340 crank
AFR 1038 75cc heads
MS909HK main bearings
CB663HNK rod bearings

I would like a real lumpy cam, the heads can go up to 0.600 in. lift

oh and here's where the engine is going :cool:
It appears to me that you are putting tgether a quality build. With that in mind I'd grab a set of quality pistons that meet your DCR requirements, i.e, Wiseco, Ross, etc.. I'd go with no less than a set of Probe's - all forged of course.

But, you're at the point that you need to match your compression requirements to the cam for your application. IMO they should be bought together with this in mind. I'd be looking for all of input that I could find. If I were you, then I'd be contacting some manufacturers such as Lunati and Crower and some serious engine builders like Straub, JET, etc because I don't have that kind of knowledge. You've already spent a chunk of change and looks like you're ready to spend some more and it would suck to find out later that you boogered up the combination by guessing at this point.

Regarding your HP goals, personally I'd find it hard to believe that you won't be able to hit 500HP with a bad combination of parts.

Good luck and keep us posted on how it ends up.

Best of luck - Jim
 

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A few things to consider while gathering parts for this build.
How much boost are you planning on running? The amount of boost will determine weather you can get away with a shelf piston or require a piston with a thicker head and the ring pack moved down (Custom) Along with thicker piston heads, a wrist pin upgrade will be in order.
As your boost level and HP increases, the ability of a factory block being able to contain all of your parts diminishes.
You will need boost referenced carbs, if your running carbs.
A good set of head studs will be in order as well.
Fel-pro head gaskets will be pushed to there limits. You may want to investigate a set of Cometic MLS. As boost continues to increase, a stainless steel O-ring and receiver groove + solid copper head gaskets will become necessary. (I doubt you will get to this level)
I'm not trying to scare you, just make you aware of things that will need to be addressed so as not to ruin your project.
Spend some time on the telephone with a couple of different piston manufactures as well as cam companies. They will/should be able to provide plenty of good information.
Remember things can go wrong real fast with any boosted engine. Take your time, do your research and most importantly have fun.
 

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The piston you linked from Wiseco will meet your needs, it is a 29cc dish(the picture is wrong, typical Jegs or Summit listing failure, they just use a Generic Picture) for use with a 3.75" stroke crank and 6.0" rods....it will result in about a 7.4:1 compression ratio with a 75cc head.
Lopey cams and blowers don't get along well, it blows too much of the fresh intake charge out the tail pipe. Need to keep lobe separation in the 110-114° range to help prevent this.

I would suggest you talk to BDS(Blower Drive Service) for real answers about blower cams and your compression ratio.....don't go to Wieand for blower info.
 

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Discussion Starter · #11 ·
So I ended up getting 28cc dish Pistons made by JE should put me around 8:1 if I'm right. And I got scat 6" H beam rods with arp2000 3/8 bolts ! Should be a strong engine I think, going to call about the cam now:)

Dumb question a stock rad probably isn't good enough for a blower is it? Thanks guys
 

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Discussion Starter · #12 ·
I get 8.05:1 with zero deck height. Might want to ake sure you can pull this off and check the pistons and heads for volume once ready to install. Published specs are usally close but not always close enough for blower setup. Best to check the heads to be sure when ordering pulleys. Want to start off safe.

Zero deck is important if your going for max boost. The quech height should be correct for less chance of detonation.

You will also want and air fuel guage so you can see if it goes lean while driving. A lean blower motor can eat itself in seconds. You should always read a little rich in the boost for street motors. A wide band is the only way to go so you can figure your air fuel ratio.
ok i will check all that, awesome info thanks!

now for the worst part, the waiting game....pistons and rods don't ship til july 14th :(
 

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Discussion Starter · #13 ·
I just got to ask again is the rear end stock? You may find the blower motor will beat on your stock rear like crazy and it might not survive long. And they are expensive to replace or upgrade. In the end they will be hard pressed to take 600 hp no matter what you do to it. By that time most end up with a 9" and tubs.

If its stock dont put slicks on the car with blower. That will cause the failure much quicker. Street tires will just spin and not put to much pressure on the rear. A good drag race launch with slicks can break a lot of things. In the stock chassis car.

Also have you checked it for rust under the car behind the drivers seat where the roof piller form. That is where the frame of the car goes into the body. Normal rust area. If its rusty better get it sorted.

In all 600 hp will find all the weak spots really fast. Anything the break should be considered epweak and upgraded once the engine is done. Cars with that much power take time to sort out. Just wanted to give you some more info on the build not sure of the goals but motor is usally the last thing to go into the car.
for now it will be stock until i can afford to fix it...this has been an expensive project thus far. stock rad good enough ?
 

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. Stock radiator should be fine for occasional bursts of boost, if you use boost a lot, that's another matter...
 

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Discussion Starter · #15 ·
im only building this to cruise around show off and do WOT just a little bit here and there. I would like a new rad, it's going to take time though , I'm spending everything on this engine lol go big or go home
 

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Discussion Starter · #16 ·
I think i would bite the rad now. Much more than stock hp can over come them easy also your old one has 40 years of trash inside it.

But the main reason i say get it now is because its a c3 vette and a big rad is not going to be a bolt in if its sized correctly best to get it sorted while the engine is out of the car and the hood is off. Just makes life much easier. I would atleast call and see how mich rad you will need for your hp goals. If your hitting 600 hp your rad will be over come half way thru a good burnout and the engine will be heat soaked then pop the head gaskets next time you floor it. Yeah not likely if your easy on it but certainly possible and with an expensive motor you wouldnt but crappy oil in it roght why use old rad with scale and other trash floating around in your new motor. A stock new aluminum radiator is cheaper and may help the old brass job will be over come by 300 hp. Add ac and auto trans now your down even less. In most cases they are not even good enough for the stock engine after this many years of build up.

Are you going to have ac and auto trans? Got to think about how well this will perform. Your motor should not be at risk over something as simple as a cheap 300-600 dollar rad. Just depends on what you are willing to risk. Its always best to do it right the first time. Imagine trying to fpget a new rad in the car that a few inches thicker and have to fight around the big blower pulleys. Might be one hell of a job.
i like your idea to do rad before engine goes in!
 

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Discussion Starter · #19 ·
Oh man well I was told it was ok for a blower? They ordered it I'm sure I can order a different one!

Can someone here tell me which one I'm stumped the cam is the only thing I'm just not grasping :(
 

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Oh man well I was told it was ok for a blower? They ordered it I'm sure I can order a different one!

Can someone here tell me which one I'm stumped the cam is the only thing I'm just not grasping :(
Street car I assume? Where do you want the peak HP? What rpm? 5000, 5500, 5800, 6200? Just keep in mind the higher the desired HP rpm the more you take away from driveability on the street.
 
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