Ok i plan on turning my 350 block into a 383. I have a couple questions on my decision. I'm hoping for 500 crank hp. It is going to be a strip/street car. I also plan on Splaying the main caps also. I think i will be porting + shaving the origional heads with 2.02/1.60 valves. Edelbrock air gap intake and holley carb will be used.

Is this a good, reliable rotating assmebly to use?
http://www.summitracing.com/parts/SCA-1-40755BI/
What cam to use? What is the kit clearenced for? (what to use for valvetrain???)
What compression ratio am i looking at?
How many rpm can it handle?
Does anyone also know if this kit comes with a balancer/flexplate??

Any other suggestions are greatly appreciated.
Thanx KEvin

 

Splaying the main caps is an expense you don't need to go through.

What are your original heads?

 

Well i either got my 305 heads off of 87 camaro. Or 082 350 heads (i think?) they are pretty crappy stock, i think 76cc? idk What do i use?

block is only 2 bolt, and is 2 pc rear main seal.

 

thats a nice bottom end kit. and 500 hp goal should be no prob. with that c.i.d. and that rotating assy. but niether of those heads really are. for the money your gonna spend there, just yourself the favor and go aftermarket. also keep in mind the poss. need for a small base circle cam, which would need longer pushrods, among other mods.

 

not all kits require small circle base cams you can call summit tech or Jegs and they can point you in the right direction to save you the hassle

 

also when u r ready to order i can get u everything cheaper then summit, also valve train should match your cam specs, push rods length should always be measured to determine what length u need, typically speaking i-beam rods are good to 7000rpms but not for sustained periods of time and that depends on the rods bolts, balancing, and getting a good build and proper break in on the bottom end of a fresh build, scat does sell kits that include the flexplate and balancer usually 2-300 extra if you have them balance the kit also, approximate compression ratios can be determined if you call summit give them the item # and ask them, I would definitly go aluminum heads, as far as cam shaft selection just do a quick "500 hp SBC build" search on yahoo you can get a lot of ideas there

 

Which 305 heads do you have? Getting 500 HP on stock heads is going to be a bit of a tall order.

 

stock heads is gonna be tuff gettin you to 500hp. whats going to be the primary purpose of the car? you say street/strip but is the strip only like 3 times a year and daily driver after that? most american street cars stay under 7000 rpms

 

ok well i am somewhat on a budget but say if i were to go with a cheaper bottom to get better heads, what bottom rotating assembly would you guys choose? I think this is going to be a street car more than a strip car. No nitrous is going into this motor.

Also hydralic flat tappet vs hyd roller???

 

305 heads have small chambers, getting a 383 under 10 to 1 with iron heads will be hard to do without a fairly big dish piston.

If you must stick with iron head, start with a 350 head and hog them out. You can get some good flow out of some old iron heads with new valves cut and fullly ported but it wont be easy and if you cant do it yourself, then money to port out iron will just about buy you new heads anyway for few hundred more.

No nitrous then you dont need forged internals but may still need to turn some rpm so get some good rod bolts. I like the scat I beam rods with 7/16 rod bolts. You can get the cast version of the scat kit you chose above. Its 800 bucks or so, i cant remember.

I'd get a smaller base circle cam just because they generally dont cost much more if any more at all, and you will know for sure they will clear just fine.

duration and lift will depend on how well those heads flow and the CC's of the port once all done, and also the intake setup you intend to use.

 

id go with maybe there https://shop.enginekits.com/osb/specials.cfm forged kit for 999 or an eagle kit for 899. most of your kits with cast crank, i beam rods with hyperutectic pistons can handle 500hp

 

ok thanx for the input! I think i'll prob look inta a cheaper balanced kit with hyper pistons then. If i get something like cast crank, forged i-beam w/ strong rod bolts, and hyper pistons, how high rpm can i go? Is a good choice to go 6" rod?
Anyway thanx for the suggestions and keep them coming!

 

6" rod is better for higher rpms and its usually easier to balance the crank with longer rod. Longer rod means less piston weight to throw around and thats much easier on the rod bolts/bearings. I'd feel confident in about 6500 rpm on cast stuff. Look to peak hp in the 6000-6200 rpm range. Some guys have gone higher, all depends on the tune and rod bolts mainly.

 

k awesome.

So if i got a rotating assembly that says its internally balanced, but doesn't come with flexplate or damper/balancer, would i get a flexplate and balancer that was also internally balanced?

 

I agree 6 in rods are the way to go. just make sure when you pic your cam you stay within the idle to 6500rpm range if you pic a cam that goes from 3500rpm to say 7500 rpm then you are just waistin power. And make sure you pic a cam that will work with your current stall converter otherwise getting one that matches your cam will cut into your budget

 

SBC are internally balanced as far as 305/350's go your you should be able to keep your old harmonic balancer and flexplate as long as they are in good condition

 

if its internal balanced assembly you need neutral balance flexplate and balancer/damper. Stock damper can work but its not recommened for higher rpm use. New ones can be had for under 200 bucks that should work.

stock flexplate i believe uses small counterweights on it since its a mix of internal and external balance. If you use it, you may need to knock off the weights or just get a new one, they are like 70 bucks

 

ok well i think i found a good rotating assembly that i want.
-Scat cast crank
-Scat 6" i beam rods with the 7/16" bolts
-Forged Flat top pistons

Heads i will choose to work with:
http://cgi.ebay.com/ebaymotors/New-c...Q5fCarQ5fParts

Compression will be around 10.5:1

My buddy is going to school for automotive and he said he can assemble the heads for me.

So i would like to get a hydralic flat tappet cam because cheaper. What would u guys suggest. Im looking at a 4 speed manual (muncie), 3.73-4:1 gears, a nice sticky street tire. Like i said, mostly a street car but it will be at the strip sometimes.
thanx

 

im going with a 4 speed because of sentimental reasons.

 

well? how's the project coming? i just found a muncie cheap that i am bargaining for. i would like more gears but the budget iis holding me back right now. Scat stuff seems to be real nice compared to other brands, and you can't beat the bang for buck ratio.
if i do swap the 700r4 (mid series) for the muncie, i figure i will be able to handle the torque of my 383 and save a ton of pulled muscles when i have to pul it. the only thing i can see as a disadvantage is the lost gas mileage. honestly, i'd pay more for gas to offset the broken 700r4's i'd be replacing anyway. plus i would much rather be banging gears!

 

NO!!!!!!!! not that question again, itll start a war on the board,lol!!!!no but theres been plenty of talk on that subject so look around.......goiod luck 383 is fun.....

 

Well its been i while but im getting things figured out. First off for the 383, I got that pretty much figured out except for the valvetrain. Scat components: cast crank, forged i-beams, and forged flat tops and assembly will be balanced. Then RHS 64cc heads with 220cc intake. I believe i want to get a summit 383 block instead of the machining my old block. Anyway the engine will be built this fall + winter.

I did pick up a 4-speed Borg Warner Super T10. 2.64 first gear. I also got all mechanical clutch linkage, shifter, crossmember + torque arm (spohn) and clutch for the car (1987 camaro). This winter also i am going to be getting a ford 9" built for this car with 3.73's.

The car is currently is stripped down to just a shell. Car does have rust, needs new floors. But the rest is all pretty much minor. Here is link https://www.thirdgen.org/forums/engi...t-rebuild.html.

But overall most of the planning is done. Once rust is taking care of, new suspension and steering is going in front of car, then transmission, then rear end and new rear suspension.

 

i have rhs vortec heads with the 170 cc intake that i got bare, they are older, but the machining is top notch! i had the machinist lap the valves to the seats and added all comp components to the stainless valves. i'm using an xs282s cam til i can afford a set of bigger port aluminum heads and a roller cam. one nice thing about the rhs vortec heads is they are already cut for 1.44" springs, i have had to go above 1.25" in the past and trust me, it's a pain to figure that out after the engine is assembled (DOH)!
i used wiseco pistons to give me a c/r of 9.7 (maybe not enough for the cam?) because i am trying to be able to run on medium pump gas (89 octane) to save $$$.
Quench, via the head gasket looks to be right at .039 which is as close as i gould get to the holy graille of .040.
1 5/8" headers (shorties) are not optimum , but i didn't have the extra bucks to go with a different torque arm and run true duals. maybe in the future.
keep up the good work!
i'll let you know how things progress,,,,,,
Eric B