i know the 2.4L engines in the z24 cavys and some other cars are really beefy engines. however im wondering how much hp a STOCK bottom end can hold?
im working on a build that involves fully upgrading and building all the internals, including a vortech SC, nitrous, rods and pistons, cams, port and polished head and all the bolt ons, including all the fule management system with the SC.
but i dont want to hurt anything, so what is a safe amount of hp to stop at before i hurt somthing in the bottom end? im assumming the 2.4L will be able to hold at least 300 hp stock bottom end with no problems if the intergra engine (the 1.6L) can hold like 250 hp stock bottom end.
thanks guys!
what does Hp have to do with Detonation? Detonation can occur at any Hp rating. Detonation comes from poor tuning or a lack thereof. 14.7 psi of boost pressure would only increase rod load by 20%. Boost doesn't kill an engine, detonation does. Forged internals won't stop detonation from occurring, merely hold up better against it's effects.
All USDM Integra's have 1.8 liter engines with the exception of the 1st generation Integra's, they had 1.6 liter engines, and 92-93 GSR, they have 1.7 Liter engines.
something that the Honda engines have that the LD9 or the ecotec motor doesn't have is a forged steel crankshaft.
<a href="http://registry.gmenthusiast.com/images/huggybear/RCV6%203.JPG"><img src="http://registry.gmenthusiast.com/images/huggybear/thumbnail_RCV6%203.JPG"</img>
^^^i thougth they eco had a steel crank? either way, its good till around 500-600hp.. thats more then ill ever push or come close to. its mainly the rods you have to worry about. the car didnt come boosted so there is no reason to use stronger internals like an sr20, or an rb25. the reason those engines are so strong and u can just crank up the boost, is the factory forged internals.
I know ppl with completely stock 2.4s running 12psi with no problems
I'd be more concerned about busting a piston first or blowing a head gasket
1989 Turbo Trans Am #82, 2007 Cobalt SS G85
HUGGY BEAR wrote:what does Hp have to do with Detonation? Detonation can occur at any Hp rating. Detonation comes from poor tuning or a lack thereof. 14.7 psi of boost pressure would only increase rod load by 20%. Boost doesn't kill an engine, detonation does. Forged internals won't stop detonation from occurring, merely hold up better against it's effects.
Who said anything about detonation... or forged internals?
There is a hp limit on the stock bottom end, have you ever seen the stock rods?
4cyltuner.com - Information Source For 4 Cylinder Tuners
Buy stuff from CarCustoms Ebay! Won't be disappointed!
Shifted wrote:275ish WHP is where she'll snap, I wouldn't go over that on a stock bottom end and expect it to last.
Why are you saying that it cannot hold over 275 whp?
275hp & 306tq - 1999 2.2 ohv
13.2 @ 108 mph
-1996 2.4 liter + Turbo + Built motor + Torco + More boost = Lots o' Power
-2000 Mustang GT + 2004 Cobra motor, Whipple 2.3 supercharger,
built rear-end,Dodge Viper spec T56 6 speed, bolt-ons = wheelies at the track!!!!!
I remember reading somewhere in an engineering report or something that the stock bottom end can't hold more than 300hp on a perfectly tuned engine. If I could remember or find the thing I read it in, I'd put it up to see...
Regardless, if you've seen the stock rods (which I know you have), then I'm sure you can understand how that much pressure could cause them to snap. Thats the weakest point of the LD9 bottom end.
4cyltuner.com - Information Source For 4 Cylinder Tuners
Buy stuff from CarCustoms Ebay! Won't be disappointed!
Knock (early detonation) is the number one killer of a bottom end like HUGGY BEAR said. That is why i have a Knock Gauge. Also i know what Shifted is talking about.. The bottom end can only take 300hp which is a fair amount, i think even GM has said that... but with knock you could be running 220hp and still have your bottom end blow out on you.
LOL
dude you are a trip as if HP does any damage to a motor...............i better go out and get autometer to make me a HP gauge so ill know when im making too much HP that way i can back off the throttle and save my enigine.
Detonation and Preignition are what kills an engine. It's with higher boost pressure and higher combustion chamber tempratures that the chance for detonation or preignition occurs. HP is merely a measurement of how much work a motor is performing. I can see your arguement somewhat as you are approaching the 275-300 Hp mark the thresh hold of detonation begins to become harder to tune out. and the weak cast internals just cant take it. But to say that Hp destroys engines is pure stupidity!
<a href="http://registry.gmenthusiast.com/images/huggybear/RCV6%203.JPG"><img src="http://registry.gmenthusiast.com/images/huggybear/thumbnail_RCV6%203.JPG"</img>
he huggy stop being a smarta$$
i think they all understand what you are telling about but the nearest point to breakout is about 300 hp proved by GM engieeners.( yes it's a well tuned engine with proper fuel so no preignition or detonation) So we CAN said that around 250 (on a not so well tuned engine) is a safe point. If you have a completly untuned motor that's a different story.
And for sake, tuning engine is not changing parts in it, it's getting the proper fuel/air ratio to run the engine without detonation and/or preignition.
"But to say that Hp destroys engines is pure stupidity!"
LOL, saying that is stupid.
Think about whats happening. Hp is a product of torque and angular velocity. Torque comes from the cylinder pressure combined with the cantilever design of the crank. (the stroke).
If you increase the cylinder pressure (increasing Ve, or adding boost), you're going to make more hp. That cylinder pressure acts as a force against the piston in order to generate motion.
So it comes to a point when you have so much cylinder pressure that the piston, or rod, or crank, (or even block), cannot withstand the force, it fails.
All the parts in your engine are designed with structural integrity in mind. Forces on the parts create stresses in the metal that must be anticipated to function correctly.
ie. stock bottom end parts are not designed to withstand 300+ hp, thats why they fail, and you must buy aftermarket pieces to withstand the higher loads.
This is similar to how high rpm kills rods. At 6000rpm (6000 is not that high, just a easy example), your rod has to move your piston from tdc to bdc to tdc 100 times per second. Considering your piston weighes 500+ grams, that rod is seeing enourmous amounts of forces.
If you honestly think its detonation and preignition that kill engines, I want to see you spray n2o or boost it to extreme amounts, additionally running a methanol sprayer. The methanol with eliminate detonaion gaurenteed. Then you'll understand.
I can't believe you're making fun of a guy when you have no clue whats going on.
2000 z24
Huggy Bear-
So metal is indestructable huh? Doesn't stress fracture? I'd love for you to go into a ductile metals lab and say that outloud. HP is a function of torque bud, ever wonder why dyno graphs of HP and TQ always cross at 5252 RPM? Torque is a real world measure of the stress on the rod, the energy has to get from the top of the piston to the crank somehow.... yup, you guessed it, right through the rods. The stock rods are thin like little pencils, and WILL BREAK AT A CERTAIN POINT.
4cyltuner.com - Information Source For 4 Cylinder Tuners
Buy stuff from CarCustoms Ebay! Won't be disappointed!
Hp does play roll in this, but Knock is the main killer of boosted engines..... Any one planing to run boost should have a Knock Gauge... i would say it is one of the best things to have as you can see when/how much knock your getting and there for have a chance in preventing your engine from grenading its self on knock..
Supercharged 2.4L
By bottom end, do you mean rods? If so, they cant take much. I broke a rod at 60K on my 2.4, threw it out the side of the block, POS motor.
http://members.cardomain.com/vertz24 1998 Z24 Convertible
Quote:
im working on a build that involves fully upgrading and building all the internals, including a vortech SC, nitrous, rods and pistons, cams, port and polished head and all the bolt ons, including all the fule management system with the SC.
Right here he says he is replacing the Rods and pistons, so techinically he is really only asking about the crank and the block, nothing else would be stock ! So to get back to your question:
The stock crank can handle aroung 300hp @ the crank before it begins to twist. The block will run well over 500hp before it even thinks about cracking. There are alot of things to consider if you want to go over the 300 mark. Might want to look into o-ring the block and running a metal Headgasket ot even a spacer to low the compression ratio. Once you figured out how far you want to go come back and ask questions like this.
What would be the best pistons and or rods for xxxhp (or WHP) ?
What would be the best metal gasket to get for xxxhp (or WHP) ?
Then we can help you out a little more. you can also take your block to the machine shop and hope they can just hone the walls and not bore it out, the thinner the walls the less pressure (HP/TQ or what ever you wanna call ti) it can handle.
<img src=http://domestictuners.com/banner.jpg WIDTH="400" HEIGHT="75" /img>
Hit 200 NA it broke once, Hit 213 it broke again,
Hitting 300 NA is further away than I thought.
Rol N A Z (AKA: ImportHater) wrote:Quote:
im working on a build that involves fully upgrading and building all the internals, including a vortech SC, nitrous, rods and pistons, cams, port and polished head and all the bolt ons, including all the fule management system with the SC.
Right here he says he is replacing the Rods and pistons, so techinically he is really only asking about the crank and the block, nothing else would be stock !
CaliforniaCavalier wrote:
however im wondering how much hp a STOCK bottom end can hold?
Actually, he is asking about the STOCK bottom end, which includes pistons and rods...
4cyltuner.com - Information Source For 4 Cylinder Tuners
Buy stuff from CarCustoms Ebay! Won't be disappointed!
[quote=Rol N A Z (AKA: ImportHater)
The stock crank can handle aroung 300hp @ the crank before it begins to twist. The block will run well over 500hp before it even thinks about cracking.
That is incorrect. Where are you getting your information from? Mike Karas put down over 400hp out of his 2.4 with the stock crank without any problems.
275hp & 306tq - 1999 2.2 ohv
13.2 @ 108 mph
-1996 2.4 liter + Turbo + Built motor + Torco + More boost = Lots o' Power
-2000 Mustang GT + 2004 Cobra motor, Whipple 2.3 supercharger,
built rear-end,Dodge Viper spec T56 6 speed, bolt-ons = wheelies at the track!!!!!
