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Discussion Starter #1
What J-series motor would be the best for an NA build with minimal torque. I was thinking the J30a1 because it is the only motor you can put a header on.

Plans i would have for a motor build would be:
Slight bore + sleeve
Balanced, lightened, and destroked crank
High comp custom pistons + custom rods
Custom Race header
Complete valvetrain
PnP head
Custom Intake
Custom 3" exhaust (already have)
Best possible tuning program idk yet

This would be a race motor put in a 00 civic, so i dont need a big 3.5 litr with a lot of torque.

Im not sure if there is a company that makes aftermarket cams with a high lift but i havent found one yet.

Im not too worried about what motor has a good base hp, i just want to know which motor has the best potential NA without too much torque.

I was also looking at the J32a2 and doing basically the same thing except the sleeve/bore and header

Balanced, lightened, and destroked crank
High comp custom pistons + custom rods
Complete valvetrain
PnP head
Custom Intake
Custom exhaust all the way up to the block/exhaust mani
Best possible tuning program idk yet


With either motor, j30a1 or j32a2, i would be looking to end up with something close to a 3.0 litr whether it be by boring/sleeving or destroking and what not. Im just not sure which motor would have more potential.

Also ive read that its hard to get a 6pd to bold up to the J30a1 so idk.

Any suggestions would be appreciated.
 

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I was thinking the J30a1 because it is the only motor you can put a header on.
Since when? J30A1, J32A1, J32A2, J35A3 all have standard heads without cast-in exhaust manifolds that I know of.

]Also ive read that its hard to get a 6pd to bold up to the J30a1 so idk.
^--No.

Also, you do realize HP is a direct mathematical result of torque, right?

You should do a little more research first. A build like that is going to cost you something insane. Check out some of NVA-AV6's builds, they aren't cheap. Also there is absolutely no need to sleeve an NA build, even using Nitrous. Some of us on the TL forums have ran 150 shot on stock blocks without consequence (though I dont recommend nitrous). I'm sure if you check around here there are others doing the same.

best tuning program will be E-Manage Ultimate, though more than you would need for an NA build of this type.
 

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Formerly VTEC-v6!
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What J-series motor would be the best for an NA build with minimal torque.

This would be a race motor put in a 00 civic, so i dont need a big 3.5 litr with a lot of torque.
Minimal Torque = Minimal HP.

Not being a "hater", but if you're going to put your blood, sweat, tears and $$ into a race car, you ought to know what you're doing first.

I obviously understand the principles of a high-strung rev-monster with shorter gears for racing, but you aren't going to get that with a J-Series motor. Their SOHC valvetrain is going to keep the rev ceiling relatively low.

There are a few different philosophies when it comes to building power plants for racing, and the high-rev top-end ones don't fit the bill with a motor that won't rev past ~7K RPM.

...just my 0.02lb-ft :cool:
 

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^^ 264whp/231wtq in a 2200lb car...yea, pretty fast lol. It's basically a TL Type S -1300lbs. Probably a high 12 second car with traction.

J32a2 would be a good bet. Might as well buy the whole motor/6spd tranny together rather than piecing it together. Might be cheaper that way. 250+ whp in a Civic should be rapage.
 

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Formerly VTEC-v6!
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What kind of "race" car will this be? Drag? AutoX? Road Racing?

A J-Series is going to ruin your weight distribution...
 

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I'm a whiner
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I'd say a K series would be a better choice for a NA build. K's have way more aftermarket support than a J does. I love the J but it seems a bit heavy to put into a civic
 

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Discussion Starter #13
i already have a k series engine in my EM1. A k24a2, full bolt ons and tune, made 230whp and 190 ft lbs. I was going to do an NA build on that in hopes of reaching 300-320 whp on pump gas. Achievable, but i would of end up spending around 9k on the build, and thats with only a 2.4Litr.
2000 for custom pistons/rods
1300 for cams
2000 for intake mani
1500 pnp head
1500 bore/sleeve and crankwork
300 valvetrain


I figured that if i put that 9k into a 3.0 litr i should be able to reach anywhere from 350whp-375 with somewhere around 260 ft/lbs NA on 92octane.

By destroking and getting a good aftermarket valvetrain, couldnt you increase the rpm and broaden the power curve a little bit?
 

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Formerly VTEC-v6!
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Destroking is going to reduce your torque even more and actually narrow your power curve. The rev ceiling is limited by the SOHC valvetrain, even with custom valvetrain gear, you're pushing the physical limits at 8k RPM.

A combo of 370hp/260lb-ft puts your peak torque at ~7750RPM. You're going to need more displacement than 3.0L to hit that on these motors, and with that displacement comes more torque.

Side note: Torque is NOT bad. Torque is good, torque is your friend.

Torque is the difference when you blow someones doors off exiting a corner because they needed to grab a downshift to get into their powerband when you didn't :)
 

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"Certified Hybrid Killer"
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De-stroking is only done to 4-cylinders because the larger ones like the K24 already have super long "hail-mary" strokes which result in unacceptably high piston speeds when you push RPM. De-stroking tames the piston speeds a bit and lets you push the RPM more. And the DOHC valvetrain allows that.

On the V6 engines you have the opposite problem. Piston speed is not the issue - the mass of a heavier and cheaper SOHC valvetrain is. You can spin direct acting bucket tappets in a DOHC head to far higher RPMs than the much heavier and higher inertia rocker arm setups in a SOHC. Of course you can modify those too, but it will be ALL CUSTOM because nobody does aftermarket J-series parts. How much money you got? :)
 

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What kind of "race" car will this be? Drag? AutoX? Road Racing?

A J-Series is going to ruin your weight distribution...
^^^
This is the heart of the matter.

If you are drag racing drop the J series, get them most power you can and figure out traction second.

If you are are auto-x'ing or road racing you don't want to add the additional weight of the V6 to the nose of the car.

Like VTEC-V6 said torque is a good thing.
I think the best of both worlds would be to get the Brian Crower kit and stroke the K24 up to a 2.6L. You get the better valvetrain (DOHC i-vtec), all the aftermarket, less weight, and more power, especially torque.

edit: Just to clarify I mean more power than the K24A2, not more than a J35. Oh no.

You will loose a little rev ability, but you also won't need to rev that high. K26 is the engine of my dreams. Well K26 turbo actually. BC makes the kits for any compression and with lgithweight NA rods or heavy duty turbo rods. Look into it.
 

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Torque wins, Horsepower sells.

I'd be happier with a K-swapped car running 12 seconds than a J-Swapped car running 12 seconds. You will end up spending much more.
 

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Bobby Lane Racing
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best motor to utilize N/A would be a K-series out of a JDM integra Type R or a RSX-S. it makes more than enough torque to pull you out of a turn as long as you have LSD tranny and the motor is in a civic or an integra.
 
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