grove

iTrader: (3)

im still doing searches so spare me the do search line. now onto business. i just recently purchases a tpi 350. it has 140k on it. im gonna rebuild it. my ultimate goal is to have at least 300 ponies at the wheels. i know i need to get a set of heads. i know vortecs are good heads but i dont want to hassle with buying a lower intake mani for it. and like its been stated before, by the time you have spent all the money to install those heads and get the special intake for it your already looking at almost a grand. i might as well save a lil bit more and buy some descent aluminum heads.

i do however have a set of 081 heads that have been molested. they have 2.02/1.60 valves in it. and the heads have a fresh rebuild on them. dont know if im gonna use them though.

im gonna run hydraulic roller. i already have 1.6 rr for it from my 305. and i have 1.5 rr in the attic if i need to use those. i just not a 100% sure on what cam. i was thinking about the comp cams xr270. the cam quest program on comp cam website says that will work pretty good. any cam help would be appreciated.

induction, im gonna stay with tpi and its stock for right now. im gonna port the plenum and the manifold. runners im gonna buy slp runners. havent figured out what size injectors im gonna run. so any inputs there would be appreciated.

i already have headers and the rest of the exhaust has been taking care of. 1 5/8 headers, high flow y pipe, 3'' i-pipe, 80 series fm.

now for the bottom end. i dont anything about. i dont know if i should get new pistons. if so which ones to get. like i said i want to get 300 at the wheels. also which crank should i use, stock or should i go aftermarket?

im sure ill come up with more questions later. work is distracting me. i would like to do this with lil money as possible. but i do realize there are some parts that will cost a pretty penny like heads for an example.

KrisW

iTrader: (5)

Let me preface this entire statement by saying that although I have built some chevy small blocks, they are not my engine of choice. I am not familiar with casting numbers or part numbers by heart.

I don't see anything wrong with using a stock crank. Turn it if it needs it. At your horsepower level you can get by. In chevy engines I like to use PM rods or steel aftermarket ones if I can get them used but good. You'd be surprised at what your machine shop has lying around at a good price. I like forged pistons from Speed Pro or TRW for chevy. They are cheap but seem to be decent. I'm sure everyone has an opinion on this. I WILL NOT RUN HYPERUTECTIC PISTONS EVER AGAIN. My friend and I had one on a 355 disintegrate and make a real mess. They don't like to run lean. Forged pistons are more forgiving with me.

I like the LT4 hotcam with TPI. You will need to learn about tuning to make the computer happy but do it. You'll love it. Of course, I buy that used as well.

I don't know what an 081 head is. I do know that 305 TPI heads, or LG4 heads are a great vortec alternative and TPI likes them. You probably won't need larger than 1.94 intakes, but hey, 2.02 is cool too. Don't forget the good valve springs for high lift cams.

The one thing I have to be unhappy about in a third gen sbc application is the headers. I would pay real money for these (although I would search all the way until the engine was hanging above the car for used SLP's) and I would buy the 1 3/4" headers sold here by dyno don. For real power, you just have to. I can see people running real powerful engines and choking them through 1 5/8" headers and I don't know what to say. All I can say is, I guess I wouldn't do it.

grove

iTrader: (3)

i just read a post basically saying you dont need 1 3/4 headers unless your cranking some serious HP.

if i was to buy new pistons, what kind of pistons would i buy? flat top, domed, dished, valve reliefs?

grove

iTrader: (3)

does anyone haven any thoughts for the piston. or would i be able to re-use my stock pistons and re-use the stock rotating assembly to achieve the power level im lookin for. yes i am gonna put new main bearings and rings to.

r62mcmahon

you can reuse the stock bottom end just have it checked out. i would buy a set forged pistons. i bought a set of mahle, their power pak comes with all new rings. i would definatly change all of the bearings.

as for heads, AFR makes nice heads that the tpi bolts right up to.

KrisW

iTrader: (5)

I would get the forged flat tops with valve reliefs.

Also, I would re-think the header size. I think the 400 + (425, maybe...) horsepower that I put in a 90 firebird felt much better with 1 3/4" headers than 1 5/8". I bet that 400 horse at the flywheel would be 300 at the wheels in your car.

grove

iTrader: (3)

you think i would really loose 100 hp through my driveline? thats alot. i figured i would loose maybe up to 50 hp. i have been rethinking the headers. if i get 400 then ill do the headers again. for right now im more concerned about rebuilding the engine and getting the internals done and to make at least 300.

the flat top pistons with valve reliefs- what would be a good cam to use with 1.6 rr? what size can i go to before the valve start hitting the cylinder.

afr heads would be real nice. although they are pricey. depends on how xmas goes and my income tax, if i go with afr. what other options are there for a descent heads. i dont want to use vortecs. i know there good heads, but i dont want to hassle with getting the vortec manifold for tpi.

what about using the 081 head i have. they have been rebuilt. they have been pocket ported. they also have 2.02/ 1.60 valve. i know i have some valve shrouding with those heads. but im sure it wont be a problem with the 350. and with the 58cc chamber i should get a lil more compression out of them. i know these arent the best heads to use, but will they get my wheels past the magical 300 hp mark?

r62mcmahon

comp cams xtreme energy cam would work fine for what you want, .472 or .480 lift. the 2.02 heads should help. i bought my cam and lifters from cnc-motorsports.com they were cheaper than anyone else. i also ought my pistons from them. if you want aluminum heads another company is patriot performance, you can pick up a complete set for under $800.

S105.7

keep in mind those 081s are only 58cc heads, so your compression is gonna be up. don't go too high...iron heads like 9.5, or so, tops on pump gas.

grove

iTrader: (3)

wow the patriot heads are roughly 800 bucks right now. hopefully they will stay like that for a lil while. thanks for the links ill check them out.

3rdgenZ

iTrader: (1)

as for the exhaust, krisW is right. not only is the primary that important but the length is as well. i know a guy that dropped 4tenths off of his quarter by going from the 1'3/4 slp's to the hooker supercomp long tubes.

if you get the afr heads you wont need the vortec base. you will want to port your stock base.

and one question for you....
do you want just 300rwhp or is there a time slip your looking to get?

grove

iTrader: (3)

not really looking to get a certain time slip. yeah getting me down into the 13's or 12's would be nice. but im not constantly running to the drags. so basically im just looking to get at least 300 at the wheel. my biggest goal is to make my bird faster than my dads stang.

about the stock base, yes i am gonne port the stock base. should i polish the the base to a mirror like finish after porting?

when the engine gets ready to go in the bird ill look into the bigger headers. but right now the engine aint even close to being ready. i still need to disassemble it, take it to a machine shop to make sure eveything is straight on the block, get new/better parts, but if some of the internals can be re-used and will withstand having over 300 hp with whatever amount of torque it will create then great, saves me more money to put towards heads, cam, and bigger headers. at the same time i want to build this motor to be durable and reliable to. want it to last for long time.

KrisW

iTrader: (5)

If I build another small block chevy, I"ll be looking for this setup:

https://www.thirdgen.org/forums/engi...p-1-3-4-a.html

This is the kind of deal that will really pay out it's dividend in the end...

grove

iTrader: (3)

yeah i looked at the deal. its good, im hopin it will still be around when i feel its time for new headers. but right now im more concerned about the internals of the engine, and getting the right set of heads the right cam and the right set of pistons. im not worried about headers right now. i know that the 1 3/4 will flow better and give me more performance than my 1 5/8. dont need help with headers now. need help with picking the right internals to deliver the power i want, and still be streetable. the first thing im gonna buy for this 350 is a engine rebuild kit. the only set back right now is should i buy new pistons, or should just put new rings on them? if i should buy new pistons which ones? im looking more towards the flattops. if i run flat tops will i have an valve clearance issues while running 1.6 rr and the comp cam xr270? then that leads to another question which cam should i use exactly? im leaning more to the patriot heads because there at a descent price. something that i could actually afford. now back to the pistons, should i also buy new connecting rods.

grove

iTrader: (3)

if i just put a re-ring on the pistons and new bearing, will the bottom end hold up to put me over 300 hp at the wheels?

3rdgenZ

iTrader: (1)

ive seen people do it, but i dont know how reliable it is.

grove

iTrader: (3)

thats what im trying to find out what should i do for reliablity, budget and to get to my goal. but parts should i use that would match up and work well with each other. this is my first engine build. and i dont want to have to rebuild after a couple of years.

jamon8

iTrader: (3)

I have 416 heads witch are the old style 081 heads on my 350

they have 194 valves and are deshrouded and ported to the max

I also used stock crank and rods with some flattop hypos for the bottom end

my plenum and base are ported to the max and I ported the runners where they meet the plenum

I have bought a 400 horse longblock and this settup seems to me to be stronger than that

the cam I am using is a 268 fi comp cam with 1.6rr

I am also using 24lb injectors with the preasure set at 43

at 20mph I can break it loose with a 2.77 gear behind it

everyone says stock heads are the weak point in the motor and I agree unless you become friends with your carbite bit

r62mcmahon

new rods wouldn't hurt. as for the pistons, i would buy new ones, that way if the block you have is a std bore you could go .030 over and start with fresh honed cylinders. i've eused pistons in the past and regretted it.

grove

iTrader: (3)

that 268 cam, is that the xfi 268 from comp cam. i heard that cam wouldnt work well with stock heads. i understand that you did alot work to those heads. what did you do to get the cam to work with those heads? thanks for the info. i think im going to go with flat tops pistons.

next question, one of my buddies was talking about balancing and blueprinting, should i do this? ive heard a couple people say that you dont need to do that until you start cranking out alot of power and spinning high rpms.

jamon8

iTrader: (3)

on that cam you have to use new springs and you may have to machine the tops of the valve guides