Hi Guys!

Can you explain to me what "blueprinting" an engine means and the benefits (i.e. hp, tq) of doing this? Also, how is this done, who can do it and how much does it cost?

I have an '88, 305 TPI Auto. Use this engine model in your explanation if possible.

Thanks

 

As far as I know balance & blueprinting is building a motor's bottom end (rotating assembly) to specific factory tolerances using exactitudes uncommon for the assembly line. I have been told that doing so will release HP and torque otherwise lost in the factory engine due to poor build qualities.

But I've never had it done before so can't say for certain it's effectiveness.

Ask Daz or AcceldZ I think they are pretty heavy into that stuff.

RP.

 

That's the same as what I understood it to be...basically correcting what the assembly line was not able to do in the mass build process.

 

The other guys are correct. A performace balance and blueprint job basically makes sure all parts are as close to as each other in tolerance as possible. The machine shop will wiegh the rotating assembly and usually get all the pistons and rods to within a gram of each other. With a good balance job, they will try and get the valves, valve springs, retainers, keepers all close to the same weight, to reduce any variance between the parts. They will also check all the bearing clearances to make sure they are in spec.

This basically reduces friction in the motor, and usually promotes longer engine life, and a slightly higher, 'safe' redline rpm.

 

So does the increase in power that I have heard of come from the higher 'safe' redlines ?

Also, does balance & blueprint mean it will last longer under hard driving or are they just as likely to let go like my stock block will ?

RP.

 

i had mine done when i had the engine done last winter. they told me i would see very little HP. but that it would help to increase the engine life. as well as spin up to RMP faster and smoother. on a stock rebuild it is not needed as much as a high performance rebuild when you start to change things like rod lenght, stroke, lighter pistions and/or rods, wrist pins and any other rotating part of the engine. it should only be done when rebuilding an engine. you can not just take the engine out of your car and have it done.

i think it cost about 300 for both

basicly what every one else said

 

If you are intending on keeping your engine a long time or building a real high level performance block, a blueprint is a good idea. It won't generate any more horsepower than what the stock numbers are, but it will ensure that you do get those stock numbers at the least. My engine has been blueprinted and I am getting 254.7 FT/LB of torque from the rear wheels. My engine's stock numbers are 255 ft/lb so all in all, I'm getting a good deal there. As for life span, having parts that are up to spec will ensure that it will run a lot longer than a mass produced engine. Not that saying all mass produced engines are flawed, its just that variances in mass production process would cause engines that are supossedly the same to fail sooner, or not last under certain stresses. This is because a mass production engine is built within a tolerance number, as long as it does not have a standard deviation too far from the mean, its given the ok. You could have an engine in the + end of the deviation and an engine with the - end of the deviation. The differences is one engine takes abuse with ease while the other breaks with the same abuse...

If you are into a competition engine, then I would highly recommend it. Forrest and Forrest where we got our dyno day done is such a shop for such things I believe. Just take out the parts you want blueprinted and give it to them. I only got my block blueprinted when I swapped out the rings, but it made a difference I think.

 

A true blueprint is all the things everyone has mentioned and more. The entire engine is gone over and checked for factory specs. From clearences, tolerances, torque specs, to the size of the oil journals and coolant jackets. Every coolant and oil passage is brought to specs., along with decking and all moving parts. Generally, blueprinting is done on an engine being rebuilt, so there are allowences for nesessary machining...ie, over boring, sizing of rods and crank, etc. Basically, the perfect engine. ( if there is such a thing )
It's a time consuming and very expensive job.

 

Thanks for all your replies guys! I think I have a better understanding know. Basically, the motror will put out it's stock numbers, engine will operate smoother, longer life and very expensive.

I think when I drop in a 350 one day, I will have the motor blueprinted then. When I give the motor to a shop to blueprint, should I give them the motor complete or in pieaces? You know, like block, pistons, heads, cam so on all seperate. Might make things easier for shop and save me some cash.

Thanks again

Slade...How much did it cost you to have your engine bluprinted if you don't mind me asking?

 

Generally on a regular rebuild, most machine shops resize the cylinders, rods, crank...etc, ( if nessesary ) as part of the rebuild. They also balance the assembly. I would ask the shop about the actual blueprinting, but I'm pretty sure they would want the engine left assembled. They can determine alot of things from disassembling it themselves.
As far as saving money, if you need to have cleaning and machine work done ( which all engines do, with any miles on them ) and you need to buy a rebuild kit and/or performance parts, you're far better off to have a shop do the entire job. For the couple hundred bucks you save doing it yourself, you can't buy a warranty. IMO