[1969chevyss]

I notice that Eagle on their website eaglerod.com has a crank 3.48 stroke 1 pc. that the journal is .010 undersized for 123.75, special blowout price. Will there be anything wrong with this crank, if it is .010 under then does that mean that this crank has some work done on it. Sorry for asking stupid questions, but I just would like to know will it be ok to purchase this crank and get the undersized bearings for it.

[cobalt327]

Originally Posted by 1969chevyss

I notice that Eagle on their website eaglerod.com has a crank 3.48 stroke 1 pc. that the journal is .010 undersized for 123.75, special blowout price. Will there be anything wrong with this crank, if it is .010 under then does that mean that this crank has some work done on it. Sorry for asking stupid questions, but I just would like to know will it be ok to purchase this crank and get the undersized bearings for it.

My guess is the 0.010" under Eagle crank was either damaged or was machined wrong and needed corrected, or something along those lines. The crank manufacturers always shoot for a standard journal diameter unless you order one up different for some reason.

Just looked at that crank- says "recommended up to 0 HP". LOL

Personally I wouldn't be buying an Eagle crank in the first place. I've never had a problem w/them- but then again they were checked over before being used. I've also had no real problems using OEM cranks, within their limits.

Chances are it'll be fine, you'll get one less rebuild out of it down the road. If that is a fair trade to you for the money saved (how much are you saving?) then go for it. But ultimately, whether you buy this undersized crank is up to YOU.

[1969chevyss]

Thanks, I'm going to pass on the crank, I will continue on with buying the scat crank. I also will have my crank looked over before I install it. What cranks do you buy?

[cobalt327]

Originally Posted by 1969chevyss

Thanks, I'm going to pass on the crank, I will continue on with buying the scat crank. I also will have my crank looked over before I install it. What cranks do you buy?

The last aftermarket crank I bought for myself was a Callies, for a SJ 350 SBC. That was about 10 years ago.

Since then I have used new Eagle (cast), Scat (cast and forged) and used OEM and variuos aftermarket (cast and forged) cranks. No problems/failures to date w/any of them.

FWIW, I believe the problems associated w/Eagle cranks and rods reported years ago have been reduced to a level that's even w/the rest of the field. That said, I always worry about getting some old stock that was returned by someone. That's another reason (along w/ease of returning faulty parts) to deal w/high volume distributors, IMHO.

[1969chevyss]

I know we went over this before, but here is my question again. With the speed pro hyper piston h345acp30, which are -6.88cc and a 1.548 compression height. If I put this info. into the calculator on eaglerod.com with 64cc heads, 9.025 deck height, rods 5.7, stroke 3.48. bore 4.030 and .041 quench. I get around 9 to 4 CR. First question is in reality my quench will not be .041 since my piston are 1.548 not 1.560. What will be my quench then? Also if I use 58cc heads then will I have a better compression than using 64cc?

[cobalt327]

The pistons will increase the quench (or piston-to-deck) by 0.012". The quench could still be 0.041" if you use a thinner headgasket (0.029") to account for the shorter compression height of these pistons. You might not find that exact thickness, I believe I recall 0.032" being available in a composition gasket.

BTW, I get 10.1:1 CR using all your figures...

[1969chevyss]

U get 10 to 1 with 58cc? If so then can u get vortec with 58cc or a pair of 58cc aftermarkets aluminum heads

[cobalt327]

Originally Posted by 1969chevyss

U get 10 to 1 with 58cc? If so then can u get vortec with 58cc or a pair of 58cc aftermarkets aluminum heads

I was using 64cc to get 10.1:1.

10.87:1 w/58cc chambers. Are you looking for more or less CR? Bigger chambers = less CR and vice versa.

[1969chevyss]

10 to 1 would be perfect. So next question is I know that vortec heads are 64ccc, so do I need to do anything special such as milling or porting to get the most out of them or just rebuild them with hyd rollers.

[cobalt327]

Originally Posted by 1969chevyss

10 to 1 would be perfect. So next question is I know that vortec heads are 64ccc, so do I need to do anything special such as milling or porting to get the most out of them or just rebuild them with hyd rollers.

I'm not sure how to answer that, they are good flowing heads for a production piece, good up to maybe 450 HP w/o anything special in the way of porting.

The guide bosses will need attention or a specific spring and retainer used if the lift is much over about 0.460" or thereabouts. This needs to be checked to see where your particular heads are at for clearance between the retainer and seal.

The only reason for milling them will be if the surfaces are not flat or if you wanted to use 0.015" shim steel head gaskets, for example. The surface finish or texture needs to be near perfect as does the flatness to use shim gaskets successfully. Composite gaskets like you are going to be using will tolerate slightly more irregularities than will the steel shim gaskets. This goes for the block deck as well as the heads.

When you say "rebuild them w/hydraulic rollers", I'm not following you. Do you mean roller rockers? Or are you talking about a hydraulic roller cam?

The rockers need to be self aligning unless you install guide plates and screw in studs. Screw in studs are always a good idea, regardless if you use SA rockers or regular rockers and guide plates. Thing is, once you start doing all this to a set of production heads, the cost goes up quickly and before you know it, you are at the cost of an aftermarket head that will flow better and already has all these mods and tweaks already done, and will have thicker decks to boot.

[1969chevyss]

I meant roller rockers. Well I found a set of vortec heads for 175 bucks that has already been rebuilt. I just wanted to know what am I looking for to make sure these are vortec heads and if I get them would I need to do anything else before I bolt them up? Will I still be close to buying a set of aftermarket heads if I get these for 175.

[1986c10]

Im still learning so all my info may be off a tad but i just built a vortec 350. Idk if youre looking to make a race engine, dd, or street strip motor but i did mine with the intention of it being a street strip motor with the help of lots of info from cobalt etc. After long nights trying to figure out what pistons to use to get around 9.5:1, i basically found nothing. I ended up buying a balanced rotating assembly for about $800 from skipwhite. It included probe forged pistons dished -12cc pistons, procomp hbeam rods, scat cast steel 9000 crank, hastings rings, king bearings, flexplate and after a little bickering a harmonic balancer also. The kit isnt intended for racing as it has a cast crank and procomp rods (good/bad) but it can certainly withstand some abuse and some trips to the strip and was alot cheaper then having my stock crank reground, finding pistons that would work, redoing and pressing out the wrist pins and then spending the $200 my shop quoted me for balancing. My heads ended up being 62cc after decking, i used a .024? head gasket, quench was somewhere around .048 i believe and that all landed me around 9.7:1 compression. good luck on your build man!

[1969chevyss]

No racing at all, this car will never see a strip, but I want around 375 or better hp. I was going to buy a kit, but wanted to learn more about each peice inside my block and plus I am cheap, even though I will be spending more money in long run. I still plan on getting evrything balanced. I have my pistons, rods and crank and rod and main bearings. The block is all done from the machine shop which included clean, honing, bore to .030, cam bearings and freeze plugs. I will post pics later. Tonight I am going to press my own rods.

[cobalt327]

Originally Posted by 1969chevyss

I meant roller rockers. Well I found a set of vortec heads for 175 bucks that has already been rebuilt. I just wanted to know what am I looking for to make sure these are vortec heads and if I get them would I need to do anything else before I bolt them up? Will I still be close to buying a set of aftermarket heads if I get these for 175.

Good info, 1986c10.

Be careful when buying "Vortec" heads. What you want are the casting number 10239906 (casting has one large single hump on the end of the head) or 12558062 (casting has 3 small humps, aka sawtooth) heads from a 5.7L L31 truck engine. Some guys call swirl port heads "Vortec" heads, and in a way they are, but there not the 'good' heads.

If you have ANY doubt, post them here and we can all take a gander. I wouldn't want to buy sight unseen, especially from a private seller. Better to have the sale depend on them passing an inspection done by a qualified shop- on your dime.

[cobalt327]

Originally Posted by 1969chevyss

No racing at all, this car will never see a strip, but I want around 375 or better hp. I was going to buy a kit, but wanted to learn more about each peice inside my block and plus I am cheap, even though I will be spending more money in long run. I still plan on getting evrything balanced. I have my pistons, rods and crank and rod and main bearings. The block is all done from the machine shop which included clean, honing, bore to .030, cam bearings and freeze plugs. I will post pics later. Tonight I am going to press my own rods.

BTW, the CR depends a lot on the cam specs.

If you are going to press the pins to mount the pistons, do you have the know how and where-with-all to do this? I've built a few engines, and I don't press on my own pins/pistons...