I am getting a 350 4 bolt main block from a friend for free, so i thought i would build a 383 to swap into my 86 iroc. This is my first engine build so tell me if my part list sounds good. Im going to have the block bored to 4.030 and the stroke is 3.75. Callies 4340 steel crank, Manley I beam 6.0 rods, Je forged pistons, Federal mogul bearings, moroso pump and pan, crane mechanical roller 240/248@0.050,.543/.561 110 degree lob seperation, crane gold race 1.5 rockers, Dart pro 1 215cc heads, 2.05/1.60 in valves, edelbrock super victor manifold, mighty demon carb, msd 6al ignition and 1 3/4 heddman headers with 3 1/2 in flowmaster exhaust. Also if any experienced builders have any tricks that will keep me out of trouble. Pls tell me what u think of the combo.

 

looks really expensive

 

that will be expensive.

do you know you need .030 overbore, or is that a guess?

bring it by the machine shop, and let them look at it first, before you buy any parts, you might be a surprise...

 

Im not sure if i need .030 bore because i haven't seen the block but will be getting it in a week or so. My friend was going to build a 383 out of this block but got a crate instead. I know the blocks in good condtion. Do u guys have any suggestions on the parts u would use in a 383.

 

I am using a Manley 6 in I-beam as well in my 383. Depending on which one you chose, you might have to remove a little material so they don't hit the cam. I did, but it wasn't much at all. Best thing to do is mock it all up and rotate the assembly (more than twice) and check for clearance, then get it balanced.

sounds like an expensive and powerful engine!

 

Are you going to use any nitrous? If not, I would say the bottom end is overkill for your application. I would guess you're aiming for 520-550 hp? If so, you can get a bottom end good for 600 hp for probably less then half the price of the parts you mentioned.

 

I just meant don't buy any parts until after the machine shop has done their thing. You may need .040 bore, or something, so it would suck to have .030 pistons in the mail....
And you may need to have the block decked, which might change your piston compression height desired, etc.
Just make sure to have your machine work completed, before you buy any parts.

That is a rock solid bottom end, planning a blower or something?

 

Thanks alot everybody for the input keep it coming. Sonix I was definately gonna get the machine work done first but thanks for bringing it up anyway. Do u guys think the parts are overkill for what i want. I aiming to build an engine thats very powerful and reliable. I want 400-500 hp and i want it to be bulletproof. The parts are pricey give me recomendations for cheaper but quality parts. I saw in a summit book a worlds products rotating assembly for 1800 will that assembly handle that kind of power. Also Im not sure on what tranny to use i have a 700r4 which was rebuilt about a year ago should i beef that up or i was thinking of buying a th350 with a manual and automatic valve body so i could shift it. One more question i have is a stock block strong enough to handle 500 hp. Keep the comments coming there really helping me out. This car is a street/strip car Its not my commuter so its only used on weekends and i will bring it to the strip once and a while, so i want it to be a wild engine.

 

stock block will be fine.

your basic aftermarket forged I beams, and forged crank will be plenty strong, no need for a callies crank, and JE forged pistons. Those are quite pricey I think.

the world rotating assembly would be plenty strong. Buy parts that are rated for 600HP, that way if you get to 490HP, it'll hold out for a long time, and you won't feel too scared to hit a bit of nitrous on it later if you so desire.

trans ? for a weekend fun car, run your current trans until it explodes, then get a beefier one.

 

How much are those Manley rods? You might want to check out the Eagle 6" H beam rods. They'll be more than adequate for your power levels and they have more clearance to the cam lobes. I'd still count on getting a small base circle cam though.

 

i'd try something other than a megabucks 383 for my first engine or get someone experienced to do it for you and you help.

 

sonix i think ill take ur advice and buy cheaper parts, i think the world assembly is a good price. Do u guys got any advice along the lines of building the engine. This will be my first build and i want to build it right. Im currently in college studying automotive engineering and i think that i can pull it off. Also our teacher is bringing in one of his race engines for us to build that will help alot and my grandpa was a mechanic and he can definetely help if i hit a roadblock. Anyways i need all the info i can get before i attempt it.

 

hmm, yea i'm a university student in mechanical engineering, doing my first build also... I'm doing it as cheaply as possible. I figured i'm bound to have something go wrong, so i'd rather have a $1000 motor blow up, rather then a 3 year, $6000 motor. I'd cry a bit less.

small base circle cam, cap screw rods.... makes for less chance of having to clearance anything later.

A "healthy" 383, that'll put down 450HP honest horsepower will probably beat anything around, and you should be able to finish it for $3000-$4000...

 

Is the cam i listed too big i want this engine to have a loopy idle. I also need to install subframe connectors and maybe a roll cage. I have a stock rear no posi and 2.77. I was thinking of getting an auburn rear with 4.11 gears. What about emmisions is there anyway i can get it to pass in Ny.

 

uh, define too big? It'll be lopey alright. Don't say you want a lopey idle, as your "goal" in a build, that's almost a dirty phrase on these boards

emissions in NY? beats me. doubt it

look into a 12 bolt moser rear with that power level. I'd say 3.73, if you ever want to drive it on the highway.

 

I meant will this cam have alot of fitment problems, i want the biggest cam i can fit without to many problems. I want this car to be really fast.

 

Do you have emissions testing or not? If yes, what type?

 

cam, you can go as big as you want to drive... larger cam is harder to drive, and sucks back more gas. any cam can be ground on a small base circle, so you don't have to worry about fitment per se. As long as your max lift is supported by your heads/valve springs, you're good to go.
look up IHI's setup, 383 solid roller.

 

If i put this engine in my 86 iroc what do u think the car will run at the drag strip. Do u think the cam i listed is a good match for a 383.

 

 

I saw two 383 rotating assemblys that looked good. The first one i saw was the worlds products which is $1800 and then I saw the eagle kit which is only $945 is the eagle kit strong enought to handle the kind of power this engine is going to put out. Any recomendations for parts is greatly appreciated.

 

It should be, even stock parts could work up to 500 HP or so.

 

$945, $909, $1060 or so, are ones i've seen there.... only $100 more for forged pistons over hypers? nice...


ok, few points to note:

-1 or 2 piece RMS, make sure you get the right kit.
-internal/external balance, pay attention to that
-those had forged I beam rods, and cast steel crank, with hyper pistons. that's plenty strong.
-remember, capscrew rods give more clearance.
-piston dish/relief volume. check based on the cc of your heads, and what CR ratio you want, based on your cam needs, etc, then decide on cc volume of pistons.

 

Sonix i want the compression to be around 10.5:1 because i want the engine to run on pump gas. I think the parts im going to use is the eagle rotating assembly, the dart pro l heads, edelbrock manifold, demon carb and the cam i listed. Does this combo sound good. I didn't get the block yet but i believe its a 2 piece rear main seal and for the kit Whats better to get internal balance or external balance. I was lead to think that the internal balance was better. How much power do u think this engine will make. I hope to be getting the block this week, then i will bring it to the machine shop and get it prepped.

 

I just looked on summit and saw the kit ur were talking about $1045 Im definetely gonna step up to that kit for only 200 dollars more u get forged components. Thanks for pointed that out sonix.

 

Just skimmed through since my last post so I hope I don't repeat anything, but this is what I have to say.

I would recommend going for new rods and pistons, but get the cheapest forged rods and only get hypereutectic pistons (summit sells KB's that I've seen in 600 hp motors for $175 shipped, one of the best deals I've seen) and just cut your stock crank like .010 or so under, as the stock crank is a really strong item. This will run about $500 for a complete bottom end. If you want to spend like $1000-$1200 you can go with a 383 stroker, which is a good idea if you want some real streatable power. Otherwise, you can come pretty close to 500 hp, maybe even over, with a 350 and still street drive it, but you would need a more aggressive cam profile, probably a miniram, might be able to get away with an LT1 intake. Anyways, I say use your money wisely, if you're like me every dollar counts so I go for the most bang for the buck.
Oh, also, forged pistons and cranks tend to wear faster I hear, not sure how well founded it is but I hear it enough that I believe it (due to larger clearances for the pistons, and not enough internal dampening in forged cranks). So don't go nuts on your bottom end unless you need it.

 

I think 10.5:1 is a bit high on pump gas, but then again, you're picking an agressive cam....iron heads right? do the math for dynamic compression ratio, and watch that....

240/248, solid roller, .560 lift.... For some reason that doesn't seem like a lot of lift, for the amount of duration, and fact that it's solid roller... I would have expected over .600 ?
do lots of research on your cam, that's the biggest thing to change the characteristics of your motor, you want it perfect for you.


out of curiosity Apeiron, any guesses of power output on YOUR 383? before blowing it up perhaps? or now?

 

The old one had almost 300 at the rear wheels. Probably could have used more cam and tuning. Don't know about the new one yet.

 

Im not sure exactly what internal or external balance means. Can someone explain the difference and which i should get for my engine. I think the parts i will be using are a eagle rotating assembly, dart pro 1 heads, same cam i listed and the rest of the parts i listed in my first post tell me what u think. What will my compression be if i get 7cc pistons, dart pro 1 heads i described in first post. Any advice is greatly appreciated.

 

An internally balanced engine has all the weight it needs to balance the rotating assembly inside the block on the crank. An externally balanced engine needs additional weight on the flywheel and balancer.

All stock small blocks are internally balanced, except for the 400. Since the first 383s were built with modified factory 400 crankshafts, a lot of 383s are still built to be externally balanced.

 

...but if at all possible, you'll want the internally balanced variety -- less to worry with if you have to replace a critically balanced part later.

I asked a lot of the same octane rating questions when initally planning a turbo engine. What it really comes down to is everyone says to build the engine based upon a definite plan and then see how low octane fuel you can get away with. The two main things affecting this a DCR and quench (with quench being much more inportant, IMHO.).

 

The trick is to not let your machine shop make critically balanced parts.

You can build an externally balanced engine and swap balancers and flywheels all day to your heart's content, as long as they're all unmodified from their stock balance specs. If the machine shop that does your balancing gets lazy and modifies them, you're out of luck.

 

Ahh...I see what you mean.

 

Thanks alot apeiron thats what i thought it meant but wasn't sure ill be getting a internal balance kit. How much power do u think this engine will make.

 

http://kb-silvolite.com/calc.php?action=comp

to check your compression ratio.
gasket bore will probably be 4.166", .039" thick, deck clearance will be ~.025" if not changed from factory. (just in case you were going to ask what to put for those values). The rest should be self explanatory.