When should your engine require blueprinting / balancing

I know im makin alot of posts lately, but i finally got the money together to take my short block back to the machine shop, have it disassembled, cleaned up and reassembled. what im wondering, is should i spend the extra cash to get it balanced while im at it or is that something i dont have to worry about considering i wont be shifting at 7,000 rpms. is there an rpm standard to require balancing?
 
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Well balancing and blueprinting an engine could net you 10 or 20 more hp overall and it would probably last longer and perform better for a longer period of time. If it's not too much extra you might as well do it.
 
Balancing yes. bluprinting is really up to you. If it were me and I had the cash to get it done I would. Fact is tho that you dont really need it done if your not going to be reving high. It will however give you peace of mind and last longer most likely, unless you get lucky and your tolerences and such are already very very similiar and in range.
 
Any good machinist/builder will blueprint an engine. basically from what the machine shop told me is that blueprinting is taking all the specs of the engine and writing it down. Then in the event of a problem you can compare them new readings to the blueptinted readings.

Balancing is a must.

Why are you having your 306 reassembled?
 
Grn92LX said:
Why are you having your 306 reassembled?


I bought everything for my car to rebuild the engine about 3 years ago... my ex wife decided to leave me with about 9 grand in bills, so all of my parts had to be sold... the only thing left was the short block, so the engine has sat on a stand for about 3 years now, half of that time uncovered, so theres alot of dust and derbis in the cylinders. also, i want to check the tolerances since ive heard some bad things about the shop i originally took it to, so i want all that double checked.
 
Grn92LX said:
Any good machinist/builder will blueprint an engine. basically from what the machine shop told me is that blueprinting is taking all the specs of the engine and writing it down. Then in the event of a problem you can compare them new readings to the blueptinted readings.

Balancing is a must.

Why are you having your 306 reassembled?

Balancing any engine is definatly a must. If you are going to spend the money on a engine why would you skimp on the part that improves the durability. It would be like buying some real expensive tires and not getting them balanced. Not only would the tires cause vibrations, like your engine, but it would also wear prematurely, like your engine.

As for blueprinting, a blueprint is nothing more than a layed out on paper view of your internal engine specs. A blueprint can be done on any engine and does not change the engine or its specs. The blueprint is commonly used in racing for damage analysis and improvement on the next build. If you want the specs to be blueprinted to all match such as all main bearing clearances to be the exact same that will be up to you and your engine builder and if you are not around while it is being assembled then you are trusting what is written down on your blueprint.
 
I FEEL Blueprinting also entails, taking the rough edges or stress points away on the block and parts. I also chamfer oil galleys, passages, and polish some things up. Most good engine builders always do a spec sheet with all tolerances, atleast the good ones do. I also do a full mock up and parts inspection both before and after machining.
 
Rick 91GT said:
Most good engine builders always do a spec sheet with all tolerances, atleast the good ones do. I also do a full mock up and parts inspection both before and after machining.

Yep, my engine builder did. I still have it somewhere, but I don't know what half of that stuff means. The balancing information is self-explanatory, but all that other jargon is above my head.

Tim
 
Rick 91GT said:
I FEEL Blueprinting also entails, taking the rough edges or stress points away on the block and parts. I also chamfer oil galleys, passages, and polish some things up. Most good engine builders always do a spec sheet with all tolerances, atleast the good ones do. I also do a full mock up and parts inspection both before and after machining.

I FEEL the same way and agree totally but, you have to be careful of the exact meaning of the term or some jackass machinist or engine builder will lead you astray. You will pay for nothing more than some written down specs. that may or may not be truely from you engine.
Bottom line go to a well known qualified engine builder.
Don't forget they usually cost more. You pay for what you get in most cases.
I build my own engines and will definatly charge more for the type of engine pampering that Rick91GT describes. Well worthe the extra charge. :cool: :cool:
 
Rick 91GT said:
I FEEL Blueprinting also entails, taking the rough edges or stress points away on the block and parts. I also chamfer oil galleys, passages, and polish some things up. Most good engine builders always do a spec sheet with all tolerances, atleast the good ones do. I also do a full mock up and parts inspection both before and after machining.


Have you blueprinted a certain kids 347 yet? :D
 
It can be done.... buddies GT was a little over 2600 with out him in it, and there was still some other light weight stuff that can be done.

My goal with my new 25.5 chassis is 2800 with out me, then add weight to make the 3300 race weight.
 
The car in my avatar (mine) weighs 2800lbs with me in the car(155lbs.). It still has full interior such as carpet, seats, dash, headliner, plastic, ect. It is a 93 Gt. I have put a lot of work into finding ways to lighten the car without making it look stripped.
The car's name is Night Lightning. The name is a duel meaning. :p