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My first 350 build

16K views 135 replies 11 participants last post by  prostreet6t9 
#1 · (Edited)
Ok so ive decided to build a SBC 350 for nitrous. The goals are a 200-300 shot. For now i guess let me just tackle the bottom end as it will be a while to fund this motor and right now im at phase one, having the block machined, And purchasing a rotating assembly. The block is an "010" 68-76
4-bolt main.

This car will be a track car with very minimal street driving. I dont even have a car as of yet. First i plan to build the motor and then go from there.

I beleive i need to run an all forged rotating assembly correct? I also beleive i want a 10:1 or less compression (Id prefer to run 91). I was told for my power goals of 600+hp i will have to run H beam rods, This correct? Also the machinist guy tells me i should balance the Rotating assembly. Is this a power thing or a reliability thing? I want the motor reliable but i cant afford to do every little trick thing to make maximum power. Anything else i should look for or watch out for is much appreciated.

Also this is my first post so hello everyone. Im not here to suck up your info and scoot. If all goes well some day i can contribute usefull info of my own. Maybe this thread can continue throughout my build from start to finnish.

-Kenny
 
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#52 ·
I can tell you now I got bout 600 hp and I will smoke slicks on the street at times the street no where near as sticky as the drag strip on street tires I can smoke them at 45 mph no problem and that can get real bad real fast if you. Dont know what your doing or car does something you not exspecting it to do thats why I wont run any street tire I use drag radials and you cant always trust them on the street. You never know whats on the road between oils and other fluids. And water. Im beginning to wonder if you really know what 600 hp all about might not sound like that much but on street its more than most people need or should have
 
#56 ·
I would never run a 600+hp nitrous car on the street unless i was able to sweep and prep the whole road and the shoulders were a relatively safe exit if i lossed it. Oh ya, and the police were fine with it. Im not putting 7k into a car to have it towed off to destruction. Plus im sure thetes some jail time involved these days. no thanks.
 
#58 ·
I wish I had 7000 in mine I have bout 10000 in just my motor I have another 10000 in the car not counting what I payed for the car and building a. 421 stroker thats going have over 12000 in motor by time im done and im not on high end know a few with more money in there motor than mine got a buddy with over 20000 in his but thats good hear I misunderstood I thought you were saying you were going spray that on street with any street tire had me a little worried there for a minute
 
#63 ·
If you are building a small block they are size you need. They are just as good as Crane, Comp, etc.
Ok thats good. Now these seem to be "well used". Anything i should look for as far as play or wear? They have side to side play on the roller and the rocker but little to zero up and down play. They came to me covered in oil build up. Im soaking them in gas right now. I tried to clean one up for the picture. They seem to have a lot of marks in the alluminum, Antyhing to be concerned with? Will these be strong enough assuming they are not damaged to rev up 7k if need be?
 
#64 ·
Devil's advocate

The problem w/used aluminum roller rockers is you do not know their history. Aluminum work hardens and becomes more likely to fail w/the more use they see. If they were used w/a solid lifter cam, or high spring pressure, or high rpm, or all of the above they can see a lot of wear. Any nicks or scratches can cause a crack to develop if the defect is in the wrong place or is bad enough. I'm not saying these will self destruct, who knows, they may outlast the engine. But what I AM saying is you need to at least clean and inspect them carefully, because a rocker arm failure can- in a worst case scenario- destroy the entire engine.

After cleaning they should be absolutely smooth when you turn the trunnion and the roller tip. The trunnion can move side to side but there shouldn't be noticeable up and down play. There should be NO gritty or notchy feeling to them when clean. You can take them apart for cleaning and inspection by removing the outside C-clips. Inspect the race for brinelling and and roller elements for pitting. Use some assembly grease or vaseline to hold the needle bearings in place when you put them back together, same theory but different grease as you do w/U-joint caps and needles.

Good luck.
 
#66 · (Edited)
"Rode hard and put up wet" comes to mind. That coating on them could be from some kind of 'preservative'. Still, I would rather see you spend on a set of Harland Sharp or Scorpion or Yella Terra (I have no experience w/those), or even Comp Cams. You could even use stamped steel rockers if this isn't a high performance build.

But if you want to see if these are salvageable, take the worst ones apart and see what the rollers and races look like first. I have no idea if you can still buy replacement parts for these or not, but I'm sure you can find out.

Also check to see that these rockers take the same size stud as you are using. From here they look like 7/16", stock stud size is 3/8". Upgrading to 7/16" studs wouldn't be a bad idea, they're not expensive.
 
#67 ·
Ok now should i dunk them in motor oil and store them in a bag to prevent rust while they sit waiting to be installed? As far as stud size i javent purchased heads yet so i can just buy heads with 7/16 studs right? If these are more risk/hassle then they are worth i will gladly just buy a new set.
 
#75 ·
#81 ·
Meh. 3/8 stud is fine. Use ARP rocker studs. You are staying under 7k, right?

:D

( dont use those crappy old rockers. Get you a set of new Harland Sharps )

NO on those assault heads. Find some heads that are complete. You can find a better deal.

If you spend $7k on this motor, I will laugh at you. You can do it for way less.
You do know you can buy a big block crate motor for less, right?

:cool:
 
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#110 ·
Now here is the bottom line truth.Nitrous properly used is a tool to mph cars. Guy have converted that into a cheap(well looks that way from outside the circle)crutch for engines that if built on N/A wouldn't need it.So you end up not OWNING the hp your using because your constantly making payments in refills of the bottle and trust me that bottle is addictive.
It is for that reason a turbo 5.3 is more sensible.You paid to built it once and you OWN all the 600 hp in your goal and it will bury a 383 in gas mileage as a bonus.
 
#111 ·
My opinion:

LSx are nice- but not the end-all do-all of the hotrodding world. You can still make a TON of power using Gen 1 stuff. Just look around the next time you're at the track. You do go to the track, right? Otherwise 600 hp is worthless. TOTALLY overkill for the street. 600 hp is a ridiculous amount of power for the street and takes a LOT of work on the vehicle's suspension and drivetrain to handle it reliably. Are you POSITIVE you need that much?

Scat crank kits are preferred over Eagle.

Buy forged crank/rods/pistons and use good rings (Hellfire, etc.) if you want to use a big dose of laughing gas.

Spend some time researching the valvetrain- including the camshaft. Use 7/16" studs for cripes sake. Keep the cam lobe separation angle wide, or better yet just contact a cam manufacturer w/ALL the details of the engine and let them give you some suggestions.
 
#112 ·
LSx are nice- but not the end-all do-all of the hotrodding world. You can still make a TON of power using Gen 1 stuff. Just look around the next time you're at the track. You do go to the track, right? Otherwise 600 hp is worthless. TOTALLY overkill for the street. 600 hp is a ridiculous amount of power for the street and takes a LOT of work on the vehicle's suspension and drivetrain to handle it reliably. Are you POSITIVE you need that much?

Scat crank kits are preferred over Eagle.

Buy forged crank/rods/pistons and use good rings (Hellfire, etc.) if you want to use a big dose of laughing gas.

Spend some time researching the valvetrain- including the camshaft. Use 7/16" studs for cripes sake. Keep the cam lobe separation angle wide, or better yet just contact a cam manufacturer w/ALL the details of the engine and let them give you some suggestions.
Again its going to be specifically for the track. I realise 600hp is crazy for the street. Thanks for the tips on components.
 
#114 ·
To reiterate what cobalt said with an example:
My car has a decent N.A. 434 gen 1,a friend of mine has a C-6 with an LS-3 and hot cam.My car is lighter and I have a lot more horse power. We did a little comparitive driving,he had traction control off. both cars are standard. First gear he was 1/2 a car ahead. second gear we both broke traction and he was able to pedal better and he has superior tires. The new car also has far superior suspension and independent rear. his car handles better/stops faster/accelerates about equal in 1st and 2nd,weighs more and has less power,gets better mileage,more comfortable,quieter and the list goes on
 
#115 ·
Kenny, have you considered building a 454 big block chevy. You can build a n/a 454 motor with about 596 hp and 566 ft. lb. torque. You would need a forged 454 crank, H-Beam rods, good set of forged pistons. Heads can be iron, ported and new valves, and all new hardware or an aftermarket set of aluminum heads. Since this is a track motor I would look for 320-340 intake runner. Comp cams 294S mechanical flat tappet or equivalent with matching valve springs. Super Victor intake with a 1000 cfm Holley. Then with a 150 shot of nitrous you have 750 hp. You can look around in papers like the Trading Post,I have seen people selling 454 parts at some good prices. Everybody going stroker or 540 & up CID.
 
#119 ·
I am going switch gears alittle.Still think in the long run your better off spending into a LSx.

We have a whole career buying distress project roller cars where the builder had to have the best of everything,but ran out of money and was behind on his bills.You just missed the Drag Racer's auction in Indy where there is a number of rollers that are run threw there.

You need to decide what kind of car you want.Doorslammer,open car,etc.

It is way much cheaper to buy a roller over building one.You just need to know what to look for or post it here before you buy.Look at this link for rollers:

Race, performance & street cars, engines, engine parts, trailers for sale
 
#121 ·
One of the 17 cars at last count we bought and sold was a short wheel base center steer old Alter roadster.It was a 4 link/strut.Ran it that way for a season(it was a handful at the top end)and stretched it.A 9.90 car with a easy 1.27 60' that hooked like clockwork.We had to add wt to it.It was 1850lbs.

Seems these days once you cross the line into a 9 second car,it does get expensive.
 
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