Professional Engine Builds

disco192
03-24-2005, 02:44 PM
I posted this in LT1 tech earlier, but I wanted to hear some expert opinions on the matter. I wrote this to help explain why at home builds do not stand up to expectations set by professional builds.

Its all about attention to detail. There are alot of little things that will pull more power out of a motor than simply head flow, cam design, and bolt ons. There are things like quench and compression that can increase power. If you set up the motor to .032-.035 quench (.032 is close, but possible w/ hypereutectic pistons) it will make more power and let you run a bit more compression (there is also effective quench, but that a whole new beast involving metal expansion....).

Setting up the dynamic compression to the highest possible given the local octane available and weather conditions will net you more power. You can also squeeze more power if you use optimal ring gaps, or use a top ring gapless set of rings. It will seal better and pull more airflow out of the heads on the intake stroke as well as reduce blowby (this is usually pretty controversial, but im a believer).

Accurate balancing and running a lighter rotating assembly can also make some more power. You could also get some more power with a lighter valvetrain. If you use beehive springs with TI retainers (and maybe a good rev kit) and some lightweight valves, then it will minimize the valve bounce when it shuts (as well as reduce valve float). Then you have custom cams and assembly.

I think I am starting to ramble, but my point was that attention to the little details is what separates a quality professionally built engine from an engine that someone just throws together. Making power is all about understanding how the motor works and utilizing it.

Im sure there are other secrets that can make more power, but I cant think of them right now.

AdioSS
03-24-2005, 03:32 PM
here's something else to think about...

oil control

disco192
03-24-2005, 03:34 PM
yea, i was thinking about things like knife edging or dry sump... but thats kinda costly. Im sure theres more to oil control than that.

AdioSS
03-24-2005, 04:46 PM
yea, i was thinking about things like knife edging or dry sump... but thats kinda costly. Im sure theres more to oil control than that.
there is more that you can do...

SAR2K
03-24-2005, 08:41 PM
yea, i was thinking about things like knife edging or dry sump... but thats kinda costly. Im sure theres more to oil control than that.
Poly-Dyn coating on the crank, rods, & piston underside will help shed some oil.
Steve...

SStrokerAce
03-24-2005, 09:28 PM
How about looking at the induction system from the valve to the filter..... looking at it as a system.

Intake manifolds are forgotten on a LT1, good headers and exhaust systems and tuing both of those for optimal results.

Yeah more stuff to oil control than all of that, but your not going to do that on most builds anyways.

Bret

Boost It!
03-25-2005, 02:20 PM
yes, but there is also money.

you dont want to have a german designing a toothbrush:)
Basically, sure a dry sump will yeild you power- but are you an unlimited budget? You need to make sure you WARRANT the above. Most of the time, you are better off just putting more money into head work.

jonaddis84
03-25-2005, 05:25 PM
It depends what you mean by professional engine builds. Most of the time people buy parts and have a shop "professionally" assemble it, which changes nothing with design since they are only assembling. But that opens to a whole nuther realm of things that nobody thinks about unless you have experience/training. Things like:

blueprinting clearances,
- too tight an oil clearance will rob you of precious HP, but will keep the engine alive longer assuming they arent TOO tight.
-piston to wall clearances, same deal
-ring alignment/sizing
-bearing clearances (I know i repeated it, but its that important)
-bearing indexing (if youve ever felt the difference rotating a crank over with the bearings indexed and without them indexed youd feel the same)

there are a myriad of things though that can dramatically improve hp with design, but even if you pay a shop a "reasonable" amount of $ to design and build you an engine you arent going to get anything special IMO, they will probably design something better than a beginner could just because theyve done it so many times, but you arent going to get anything extraordinarily R/D'd unless you spend a crapload of $, which is whats nice about doing it yourself....when you have resources like this place, and just the internet, you can research and design something nobodys ever built before that could potentially make more power than anything out there like it if you put the time/effort into it, and save $ to build a second if its not what you expect

SStrokerAce
03-25-2005, 05:38 PM
I have a peferct example of the good design vs. the bad design but I'm not going to say it...

Basically you need to match up all the little things and get little gains here and there and you will have something, that's what it's all about.

Bret

Boost It!
03-25-2005, 06:14 PM
I have a peferct example of the good design vs. the bad design but I'm not going to say it...

Basically you need to match up all the little things and get little gains here and there and you will have something, that's what it's all about.

Bret
the "little gains" like ceramic coating, dry sump, knife edging etc are just simply not there when it comes to bang for the buck.

after the "big gains" have been taken care of, look for those little ones. they will cost you.

SStrokerAce
03-25-2005, 06:23 PM
Boost,

It had nothing to do with those things at all.... I'm talking compression, tolerances, quench, cam choice, spring pressures etc....

Bret