383 in My Cutty

Discussion in 'Engine / Swaps etc.' started by jonnyv713, Mar 30, 2010.

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  1. jonnyv713

    jonnyv713 Apprentice

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    Im gonna start building a 383 stroker. I have my block ready. Clearanced and bored .030 over. I am lookin to run a descent amount of compression. Im new at this kind of, but I'm lookin for close to 500HP at the flywheel. I wanna get that for as cheap as possible. Its a street car that will see the strip on the weekends too. This is what I got so far. Let me know what you think and please steer me in the right direction.

    Rotating Assembly
    http://www.summitracing.com/parts/ESP-B13405E030/

    Cam
    http://www.summitracing.com/parts/CCA-CL08-423-8/

    Intake
    http://www.summitracing.com/parts/EDL-7501/

    Carb
    http://www.summitracing.com/parts/HLY-0-80508S/

    Then I know the power depends alot on the heads, and I need a smaller combustion chamber to get my compression I want. I am planning on running E85. Also, could someone explain what the piston head volume is. What is better? Higher or lower?

    Thanks in advance everyone
     
  2. bigjoenvegas

    bigjoenvegas Master Mechanic

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    I am about to do the same thing but you gotta start off right and you can't be cheap. First off are you using a 350 block and stroking it to a 383 or the other way around? It better be a 4-bolt main or your just gonna waste your money. The Eagle brand engine parts from what I understand are pretty good but it might be cheaper to piece everything insted of buying a kit. I've seen better prices then what summit has to offer on certain parts. Just stay away from Scat, Blueprint and too good to be true deals. Also you need a good machine shop that you can trust because you need to do some machining. If you are using a 400 crank in a 350, you are gonna have clearance issues that the machine shop can fix for you. Also, you need to make sure that the cam is clear of all moving parts too! I'm not too sure about what cam size works but I would ask around to see what other people are using before you buy it. I've got my 4-bolt and I'm just gonna order the bottom end and have the machine shop put it in and balance it.
     
  3. drogg1

    drogg1 G-Body Guru

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    That intake, assembly, and cam are all good selections. The RPM Airgap flows very well. That came is perfect for your application unless you get real high flowing heads. I would say that you shouldn't have to go too small with your combustion chambers as your pistons are +5cc domes.

    I would go with more of a double pumper, 4150 style Holley carb like http://www.summitracing.com/parts/HLY-0-4779C/.
     
  4. jonnyv713

    jonnyv713 Apprentice

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  5. 413Cutlass

    413Cutlass Apprentice

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    AFR for the heads, for sure. Abit more cam, and that intake, and it should be a monster.
     
  6. JBreu

    JBreu Royal Smart Person

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    Here is what I got.and it dynoed 514 hp at 6800 rpm's.....350 block punched .060 over, stroker kit from KMJ Performance ( E-Bay), This kit came with forged Keith Black pistons, Hawk racing crank and H-beam rods--all forged -- and was balanced, included flywheel and harmonic balance---10/1 compression or close to that....good for 8g on the rpm and 800 hp...Edelbrock performer air gap intake. performer rpmcam ( 488/510), DART Pro-1 Aluminum heads, 200cc w/2.02....and a junk eddy 750 carb.....just switched to a holley 750 dp, 4779, so I bet the HP is more now.....All in all, I think it was close to 6 G to build it...but it's a great combo.... These Dart heads are awesome and made the cam "BIGGER"......BTW, was on pump 93 octane gas :)
     
  7. drogg1

    drogg1 G-Body Guru

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    Those look like good heads but with them you'll be looking at more like 10.9:1 or 11.0:1 with the rotating assembly you picked. They look like fairly decent street heads and should make damn good power. Should be good for about 475hp by my estimate. You may need a little higher flowing heads or a point more compression to meet your 500hp mark. But my estimate is low and 475hp is still good for 11's.
     
  8. jonnyv713

    jonnyv713 Apprentice

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    Alright, I'm a little scared running compression this high. Its gonna be driven on the street almost everyday. What octane is E85? I heard it was like 110 :shock:

    I'll keep looking for cams and heads then. Is it worth it running a roller over a flat tappet on the street though?
     
  9. jonnyv713

    jonnyv713 Apprentice

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  10. 86Cutlass383SR

    86Cutlass383SR G-Body Guru

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    General rule of thumb is to keep the compression about 9.75-1 with iron heads. Aluminum heads allow for about 1 more point at 10.5-1 due to the alum heat loss. This is with unleaded premium gas.

    E85 runs about 100 110 octane so you can up the compression. But, if you do, remember that unleaded gas can't support this higher compression so you're stuck with E85.

    It is possible to run higher compression on unleaded pump gas. You have to figure in the overlap of the cam. A cam with more overlap opens the intake valve later allowing the compression stroke to start later in the cycle. This is called your "Dynamic Compression Ratio". You want to keep this between 7.5 and 8-1. This is basically why engines with large duration (and overlap) cams must raise the compression ratio, to get the DCR back into a useable range.

    I know you're running a carb, but it you had some sort of eletronic timing control (like EFI uses) then you could push the compression even higher, say into the 11-1 range due to the ability to pull timing out in case of detonation.

    Here's a write up that might make this a little easier to understand.
    http://www.kb-silvolite.com/article.php ... ad&A_id=36

    Here is a calculator to help you figure out what your DCR will end up at. You must enter your cam specs and other engine specs. http://www.kb-silvolite.com/calc.php?action=comp

    One other thing to consider. Quench height. That is the distance between the top of the piston and the bottom of the head. If you keep this in the .040" to .050" range, then your engine will be a lot less detonation prone. You figure the distance from the top of the piston to the top of the deck and then add in the compressed thickness of the head gasket you're using. This is the quench height.

    I know all this makes your decisions more complicated, but the differance between a good motor and a great motor is all in the small details!

    Added info: If you can afford a hyd roller, then by all means go for it! A roller cam allows the valves to open faster than a regular flat tappet cam and therefore gives more duration than a comparable flat tappet cam. You can't compare the duration @ .050" of the two cams since the roller will open the valve much, much faster. If you plan on a cam of say 210 - 215, then stay flat tappet as there won't be much differance vs. the cost. If you are thinking of the 230 and up duration, then it's worth the extra cost. There is also the friction loss to consider with the roller cam.
     
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