Over-boreing a 330????

[dodgy canuck]

Hello all. I am new here and had very many questions about the 330 Hemi I have.

The first question is if I can bore my 330 out to be a 345?

Second is where can I buy parts for the engine from other than HotHemiHeads?

Also, does anyone know the cam specs on both the 330 and the 345? I read in a repair manual that the 330 has a lift of 0.381" intake and 0.357" exhaust, but I do not know if that is with the rocker ratio or without. I don't even know what the rocker ratio for these engines is. I assume it is 1.5, but I really have no clue.

Can anyone help me?

Cheers!

[desotoman]

IF you have a block that does not have core shift, and had antifreeze run in it all of the time, you can most likely bore it out to 3.800. I would go to the expence of having it sonic checked first. It gets pretty costly putting sleeves into motors.

I just had a problem with my race motor, non hemi, only was bored .030 over and developed a pin hole water leak down in a cylinder and not on a thrust side. You just never know. Good luck.

[LordMaximo]

First off, welcome newbie...lol...your not the first to have that big blank stare in the garage.....I was in your place 3 years ago when I picked up my first old iron hemi. Well here is the answer to your fog storm......If you want to make your old hemi reliable....and you know how the Chevy block holds up compared to everything else.......this will be worth it in the long run.
You will need about $2500.00 for the first round on that little pig in your shop. Oh did you recover all ready? I was beating my head trying to work out a logical answer to this situation a while back. I took the block down to a friends shop, we made an oil bath heat tank and set the old hunk into a low boil for a week. This was followed by three days of carefully removing the stuck plugs and frozen crank and all the other stuck items. My pig was out in the weather for more then 40 years before I rescued it. I have had it megna-fluxed and compleatly checked over for anomalies. So far so good.

To make it short, it cost me $750 to have it sleaved prepared for a new life. Sleeving is a must if you want to have a good long lasting engine. These old cast iron pigs were built as best they could back then. Since then, the metalurgy science has improved 1000% from the old days. New standards are breaking way every year when it comes to the auto industry. They are building high efficency engines out of ceramics for the next space age era in the automotive world. So, to gaurantee a strong engine against fatigue, sleeve the block and move on to the next phase.

Like I said, Chevy has been through all kinds of changes since the old days. No reason why you should not try to make your investment last as long. I have been through several old blocks, not knowing what their past life was full of. More then 90% of muscle engines have been put through severe beatings by all kinds of drivers. I never trust anything over twenty years of usage. You just simply cannot build an old block, that has been stressed beyond your knowledge, and expect it to take any seriously hard punishment. So, from experience at the track and on the street, I sleeve all my rebuilds in my garage.

Yes it is some money well spent. I know from the very first time I fire it up, it will get me from point A to point B with out any worries.
Your money, your engine, your ease of comfort knowing it will take you far down the road fro as old as it is. Logical actions save money.

[desotohemibill]

You can bore the 330 to 345 by going over .080" which is OK for these old blocks. The bore will be 3.800 which is the standard bore of the Buick 3.8-231 V-6. If you want to stay with stock rods just have them magged for cracks and use rod bolts from ARP for the 472-500 adillac. If you want to go killer rods, use a set of Chromoly H-beam rods for a Pontiac. They are tough and use 7/16" cap screws. Those bolts are as big as a small Ford 302 head bolt. The sides of the rod big ends will have to be narrowed by .010" by using a surface grinder. Don't use a mill as this will not provide a smooth enough surface. The lift on the 330 is .381" intake and .357" exhaust. The Adventurer is .431 intake and .413" exhaust. You can go as high as .500" lift on the stock cam, but there isn't much base circle left. The rockers are 1.5 ratio and the lift numbers are at the valve, not the cam. You can go with Ford valve springs. My engine uses 2.02" Chevy intakes and 1.77" Pontiac exhausts that I cut down to 1.73" to reduce valve to valve contact. The exhaust seats are Pontiac and have a thinner wall. The 440 exhaust seats work OK with a stock Desoto 1.75" valve, but the wall is so thick that it protrudes into the port which can interupt flow. Besides, the stock valves are heavy. The stems are all 11/32" and the rest of the valve hardware is SB Chevy. The exhaust over-scavenges so lift can be less than the intake.