Engine mods.......

Are there any good laymen termed books and or sites I can go to to learn about this kind of stuff? I know an engine is refered to as a air pump (the more air in and out the more power) but what about torque? Does it raise proportionatly with HP? Like I told Mike and Andy at the crawl I'm on a steep learning curve here. I've never built an engine or done a lot of engone work. But, I want to learn and gain as much knowledge about it as posiable.

the block has been decked to bring the pistons to +.020 for a quench clearance of .045 when using a Felpro head gasket.

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rods are shotpeened and have good bolts...crank turned and nitrided..rotating assembly balanced...main bearing and cylinder head studs.

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Ghost said:

...but what about torque? Does it raise proportionatly with HP?

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Horsepower, torque, and RPM are all related.

Torque = (HP x 5252) / RPM
Horsepower = (T x RPM) / 5252
RPM = (HP x 5252) / T

Torque is the equations is in pound/feet.

A little info for those who ever wondered how HP is measured. One HP is the rate of work required to raise 33,000 Lbs. one foot in one minute.

Let the geek jokes commence...

Ok, so.....

Where does the 5252 come from? And to figure one you have to know the other? No geek jokes here just wanting to learn and apply experienced knowledge.

honestly one of the best places o learn about motor is something like hot rod or carcraft thats where i learned most of my basic hot roding i do to my jeeps. I'm sure there are some good books out there to help you out...

for the VERY basics of a new subject, try
www.howstuffworks.com

Ghost, yew wanna LEARN engines?
*Cliff's Notes*: Build one!! Not that hard or expensive to do a 4 cylinder and get some dependable muscle from it.

1. Buy about three or four 'how to' books from the local PepBoys/AZ/Checker. Petersen or such, about 'camshafts and valve trains' how to hot rod', etc.
Plus, a basic engine rebuild book.
2. Buy a junkyard 2.5 w/o warranty (but a guarntee that crank, block, and head are solid and rebuildable).
3. Teardown the entire engine, taking LOTS of photos.
4. Take the block and crank to a shop; have magnufluxed, bored (as little as possible, and make sure there are pistons available), line honed, crank ground, and new cam bearings installed.
5. Have head done with three-angle valve job and trued surface (not milled, yet).

Back home:
1. Re-do the head (port, polish, relieve, cc, mill, match springs, etc.) based on your new found knowledge (from one of the books).
2. Buy the best pistons, rods, bearings, valves, springs, lifters, cam ('Stage 1' RV grind), etc. you can afford.
3. Chamfer the oil holes in the crank. Do NOT try to knife edge it for this exercise.
4. Prepare the block as in a basic rebuild.
5. Assemble everything.
6. Install the original ignition and induction and exhaust systems.

This isn't rocket science, these things were designed and built in Detroit (well, Toledo) 30 years ago.

There's nothing like hands-on to understand engines.

You can add-on new ignition and induction once you have a good foundation.

My first engine was a 1500cc MG in high school. They haven't changed much since then.

Good luck.
-Rick

Actually Rick that is my plan.....

Was just wondering if there were any recomended reading from the more experianced and knowledgable. I watch lots of speed and Hot Rod tyoe shows on TNN. Oop I mean Spike TV and have learned a lot. Thanks for the info though. Once I get that doner MJ engine I'll have a place to start.

Horsepower is not measured, it is calculated. Torque is measured on a dynamometer.

Look at the horsepower and torque curves in any vehicle catalog. The Jeep catalogs used to print them -- I don't have any from the most recent years so I don't know if they still do. Torque generally rises to a peak somewhere in the middle of the usable RPM band, then either tapers off or falls flat on its face. Horsepower generally continues to rise right to the peak RPM, but the rate of rise is steepest at low RPM and then tapers off.

Re: Ok, so.....

Ghost said:

Where does the 5252 come from?

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It comes from the relation between lb-feet and rpm vs. horse power.

(Says one who lives in the metric system, where everything is just multiplied or divided by 10 or 100 )

More specifically, power is just torque times speed, i.e. (in my metric world) hp = Nm * rpm * some constant I don't remember to convert between metric stuff and the old horsepower, which is seven hundred something Joule (1 Joule = 1 Nms, is it? (Newton meter (force) x seconds) (I can feel my physics formulas rusting away, but I hope this explained a little bit, even though I don't remember the constants)

HP. and torque always meet at 5252 rpm on any engine at any HP.

Oh ok. now that I understand. I'm learning, slowly, but learning.

Glenn, Vug isn't really that smart, he prob looked it up on the net to look cool, but he is a geek. LOL

The whole process isn't that hard, with the right book/manual to refer to for bolt torque and such will make you go "ohhhhh, that's simple" If you can figure out photography, you can do a motor.

Neil said:

HP. and torque always meet at 5252 rpm on any engine at any HP.

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I got this one, guys . . .

SPOBI alert!

If you stop and think about that for just a minute you'll see how silly it is.

LOL @ Fore Wheeler........

Yea really! I kinda figured that I just need the people with the patience to help me. It never ceases to amaze me that people cannot understand that photography is a sience and an art. And that the science is very easy to learn if you apply some basic physics to it. "The bigger the hole the more light that hits the film! The longer the 'faucet' is open the more light that hits the film! You change one you have to change the other!" Between this thread and the other one on 2.5L power I'm actually getting a lot of info.

Fore Wheeler said:

...he prob looked it up on the net to look cool

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I actually referenced a Dodge gear catalog to make sure I got the formula's right.

If you can figure out photography, you can do a motor.

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Yeah, thats tough. Point the camera at pretty, bikini clad girls and push the button. I feel sorry for ya. :looser:

Maybe you need more info... if you look at a torque and hp. graph on any engine the hp and torque readings will be the same at 5252 rpm's. That is where the 5252 comes from in the equation, it's a constant.

I'll bet you a beer Vug......

that he photographs more wedding dressed clad women coverd from head to toe than the ones in bikinis! Been there done that dont want to do it again!