ok so i started this budget build to try and get done within a month so i could have my car on the road before i ship out for bootcamp. but everytime i turn around i have to do something else.. now dont get me wrong i know it takes work to build something and do it right. but seriously why does it turn out that i have a million people telling me a 100 diff things i need to do... heres what im doing.. i have a bare 350 block... stock bore.. im boring the cylinders 30 over.. and im buying a rotating assembly to fit.. all the goes good until i get to finding a cam, heads, and well thats about it.. i got everything else figured out and going smoothly.. will someone if not multiple people help me figure this out..

first.. why does someone tell me that i need to make clearance cause the cam? is to big.. whats with that??

and i need a good cast head.. maybe a vortec but idk... keep in mind im on a bidget so im not buying brand new heads.. id rather port and polish myself..which i can do.. and then have a friend whos hooked up with a machine shop to take care of the rest if needed.. so any ideas on good cast heads???


thanks in advance for the help

 

The long stroke of the 383 means that the rods will rotate through the space that the cam rotates in. Sometimes with stock-type rods and large duration cams, the rods will actually hit the cam lobes. You can deal with this by ordering a cam ground on a smaller base circle or using aftermarket rods that have more clearance. If the interference is very, very minor, some people take a very small amount of material off the rod bolts to add clearance, but I don't like that idea too much.

 

From what I have read if you use 5.7" rods you can run a stock base circle cam. The problem is with the 400 rods because they are shorter and the rod bolts are close to the cam.

 

well all im doing as of right now is buying a rotating assembly.. which i thought had 350 rods.. the 5.7 length cause arent 400 rods like 6.0?

 

400 rods are 5.565 inches.

Here is a good read about 383 budget motor. http://www.carcraft.com/techarticles...evy/index.html

 

The bottom of the cylinder bores almost always have to be clearanced, and you should run a small base-circle camshaft. This avoids clearance problems as long as the cam is timed/degree'd properly.
Take your time and do as many mock-ups as necessary.
Be careful not to break into the water jackets around the cylinders.

 

Rod length has very, very little effect on cam clearance. You can have problems with either rod.

 

ok so pretty much from what ive been finding out a 383 is no where near going to be a budget build.. i mean the block i have has been sitting.. and sitting for awhile.. when i could just get a 400 sbc out of an impala and build that.. less machining since there wont be clearance issues and less machining since it hasnt sat in the weather for 3 years.. am i correct? or wrong?

 

Maybe, if you're lucky enough to find a 400. They weren't all that common when they were new, and in the 30 years since the last one was made, most of them have long since been picked out of the junkyards. That's the major reason the 383 exists, it's a 400 built in a much more common 350 block.

There are budget 383 builds. It's common enough that the parts are inexpensive, and if you're replacing the rotating assembly anyway, the price is essentially the same as building a 350. It does take a little more care and attention to clearance, though.

 

well thats where its killing me for my money.. the shop wants to charge an arm and a leg to do all this clearance and decking and tank dipping and i mean some of it i know i need but the others like clearance.. its nuts.. i mean idk maybe im in over my head but im hoping im not.. i havent decided if i should build a 383.. a 400 bored.. or a 355.. and what ones for my money i can get good hp and torque

 

Were you planning on doing the assembly yourself?

 

yes that i can do..i can put in freeze plugs i can do it all and if not i have a friend that can i jsut dont have the stuff to machine the block

 

I hate to say that but if the machine shop has to spend time to make things work they will charge you. Since 383 is non OE configuration (unless we are talking GM purpose built 383 crates) you will incur additional labor costs over a stock re-build.
I am building 383 right now and going through this myself, but if you want additional performance be ready to pay. If you can not then set your performance expectations to the level that your wallet can handle.
Even if you are building a stock configuration any competent machine shop must spend time checking things out. Basic machine work costs money - it is setup time, and labor hours to do it. Any time you throw together non stock configuration like 383 machine shop costs go up.

As mentioned earlier in the thread to build long lasting performance 383 expect (short block) to do:
1) oil pan vs. crankshaft counter weight clearance check and machining if required.
2) connecting rod bolt vs. bottom of the cylinder clearance check and machining if required.
3) connecting rod bolt vs. camshaft lobe clearance check
4) rotating assembly balancing (unless you got a kit already balanced)
4a) rod work unless you are getting new rods - rotating assembly kits tend to be more cost effective then if you are purchasing individually and machine work to rework old rods.
5) main and rod bearing clearance check.
6) Thrust bearing check
7) bore and hone
8) deck height and check
9) main alignment check
10) degreing cam
11) oil pump pickup to oil pump fitment and oil pan clearance check.
12) piston ring gaping for each cylinder
13) checking all threads for dirt, etc.

Engine build process requires a lot of mock-up - i.e. assembly and disassembly which can appear tedious at times, but in the end is necessary to make sure that parts fit right.

//RF

 

yeah i understand.. it takes time and time= money. it jsut sucks cause when i got into this.. and thank god i didnt buy anything for parts yet. jsut have a block sitting waiting for my decision.. no one explained clearance and all this.. i mean i think i got pushed towards something i knew nothing about and now im regreting it.. but i can change my path.. nothing is set in stone yet. so im thinking 383 is out of the question and now i need to look towards and easier build that requires less shop work..

so how does a 355 or a 400 bored over sound

i did get a little ahead of myself seeings how i need to keep in mind i have 2 and a half months left before i leave so i cant have a radical build thats going to take me forever.

 

Building a 355 or 406 is going to cost pretty much the same as a 383.
The clearancing is done with a die-grinder, and yes the mock up time will cost a little more, but that's actually something you could do yourself.
The rest of the machining and parts cleaning/prep will cost the same.

It sounds to me like your best bet is to buy an assembled engine.

 

If you're doing the assembly, then you can do all the clearance work yourself. The rest of the work you'll be paying the shop for will cost the same regardless of what size engine you build.

 

ok well i get the fact that the stuff i cant do ill have to pay either way and will all be the same.. its just i think when i considered this 383 i hadnt thought it through. which im glad i got on here first before i decided to get into something..

so pretty much i decided to just go back to my normal 355 since i have a 350 block not bored at all.. and is a simpler build for me. ill jsut put the 383 thought in the back of my mind till i get settled somewhere and can dump crap tons of money into it..

so how much hp could i get out of a 355 with stock heads just ported and polished.. and run a kinda high compression cause in reality this will only be driven here and there.. not everyday so if running on a little higher octane is what i need to do to run higher compression i can manage that..

all i need is a cam set up and a decent set of heads that are stock but flow good.and maybe what other few things i shall need to squeeze hp out here and there.. jsut going to stick within budget and be more realistic.

 

I was reading in a magazine that using the 400's shorter rods caused problems with the clearance with the cam and you had to cut into the cylinder was for the rod bolts. But it still needs to be checked and triple checked to be sure. When I get my rotating assembly I'll let you know how close it gets. But that will be next month because it's on back order.

 

The rod length has almost nothing to do with it. The major factors are the shape of the rod and the duration of the cam.

 

Who much are you going to spend? A lot of kits are made that take a lot of the work out. But if you can get the 400 go for it.

 

I was just repeating what I read about stock rods. That was what the topic was about stock parts 400 and 350.

 

ok well heres what im working with..

rods will be refurbished gm rods. 5.7
dome pistons.
stock crank.. wether its 350 or 400...
and stock block.. 350 or 400..
heads are like..993 with machine work. has 202 valves.. and ported and polished..

now what i want to know is kind of a estimate of hp/tq for the three diff motor set ups

400 bored 30 over..
355..
or 383?

can you guys help me out here?

 

Why domed pistons?

Power is determined mainly by the heads, so each of those engines would make about the same peak HP. The larger the displacement, the lower RPM the peak will be though.

 

well wont that get me more compression?
and wont higher compression build more hp?

 

Yes, if you're running 110 octane racing gas. On pump gas you'd have to pull out so much timing to keep it from detonating that you'd actually make less.

 

ok well whats cam 2 for octane?