| Go back to previous topic | | Forum name | Performance/Engine | | Topic subject | how much horsepower from 12.5-1? | | Topic URL | https://forums.2gnt.com/dcboard.php?az=show_topic&forum=i5&topic_id=22562 |
22562, how much horsepower from 12.5-1? Posted by soldier101, May-07-02 11:53 AM
How much horsepower will come from a stock engine with 12.5-1 compression pistons? and a cold air intake/w exhaust
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22563, RE: how much horsepower from 12.5-1? Posted by wakebord99, May-07-02 12:02 PM
I'ld go for.. umm 200 hp outta an otherwise stock everything + exaust + intake. W/ a fully built head.. i'ld say 250-275

97' Eclipse RS (kinda)
Present mods: HRC stage III turbo kit (12 psi street, 25 psi track) / HKS 2 1/2" cat back exhaust w/burnt cat / 16" wheels w/Yokohomo tires (215/40) / 420A engine w/ tooled crank, billet crower rods, and 8.5:1 JE pistons / Head ported and polished, 3 angled valve job Power-stop brakes w/axis pads / Ebachi Pro lowering kit (1.8") / MSD DIS-2 ignition system w/turbo retard
Near Future: Stand-alone fuel system / 550cc injectors, and fuel rail / TEC III fuel/ecu system / 17” Hart racing wheels / KYB AGX struts, w/ upgraded anti sway bars / Rear brake conversion (front to rear, Brembo in front)
Jay- wakbrd99@aol.com
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22564, RE: how much horsepower from 12.5-1? Posted by soldier101, May-08-02 01:20 AM
damn 250-275 with a built head? damn, little four cylinder can produce mad power without turbo and anything like that (for a four cylinder of course)
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22565, RE: how much horsepower from 12.5-1? Posted by mcgyvr, May-08-02 01:41 AM
those numbers are way high. If that was true everyone would just rebuilt bottom end for 1000-1500 bucks and not get turbo. I bet 200 max. isn't it only a 4% increase per point of compression so 9 to 12 would be 12% increase in HP over stock. so what only gaining like 20horse or so assuming 140 stock hp
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22566, RE: how much horsepower from 12.5-1? Posted by soldier101, May-08-02 01:49 AM
hmmm I wonder, if I do a 5 speed swap, rebuild with 12.5 - 1 compression (that's the highest right?) and then get a stage 3 clutch, with some nitrous, and a fully built head....I wonder what type a 1/4 mile I would run
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22567, RE: how much horsepower from 12.5-1? Posted by SaberKhan, May-08-02 02:00 AM
By increasing compression, you're also increasing the potential for power. True, you'd only get 20hp or so from the compression increase over stock, but the bolt on mods you add will have a far greater impact due to the higher compression ratio. Ported/extrudehoned intake manifold, bored TB, CAI, header, catback, stiff springs with oversized valves and some mean cams. Bam. Then you'll *definitely* be in the 200+hp range. Which is exactly what I plan on doing. :D
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22568, RE: how much horsepower from 12.5-1? Posted by soldier101, May-08-02 02:05 AM
ditto
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22569, RE: how much horsepower from 12.5-1? Posted by Breezio, May-08-02 04:01 AM
you can go higher then 12.5:1 but it's not recommended and you'd have to mill the head or get a custom/stroker crank to do it. and yeah, just doing compression won't yeild much.. but the more other mods you do (ESPECIALLY CAMS!!) all yeild their own percentage increases which will be higher if you are running high compression. Any mod that increases power in percentages and not a set amount will yeild more and more power when you do other percentage increaseing mods to the car.. such as exhaust, intake, cams, cam gears(adjustable), and such.
with that being said.. just 12.5:1 will get you probably 20HP like the other guys said.
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22570, RE: how much horsepower from 12.5-1? Posted by babybeclipse, May-08-02 06:32 AM
>stage 3 clutch, with some nitrous, and a fully built head....I >wonder what type a 1/4 mile I would run?
I don't think you will want to go with a stage 3 clutch. You wouldn't be able to drive that thing on the street! Plus- I hope you mean a 25 shot of nitrous. Your tuning window narrows with 12.5 comp ratio and nitrous.
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22571, RE: how much horsepower from 12.5-1? Posted by wakebord99, May-08-02 06:46 AM
As far as i know.. NOS increases compression.. much like a turbo, so make sure u know what u'r getting into

97' Eclipse RS (kinda)
Present mods: HRC stage III turbo kit (12 psi street, 25 psi track) / HKS 2 1/2" cat back exhaust w/burnt cat / 16" wheels w/Yokohomo tires (215/40) / 420A engine w/ tooled crank, billet crower rods, and 8.5:1 JE pistons / Head ported and polished, 3 angled valve job Power-stop brakes w/axis pads / Ebachi Pro lowering kit (1.8") / MSD DIS-2 ignition system w/turbo retard
Near Future: Stand-alone fuel system / 550cc injectors, and fuel rail / TEC III fuel/ecu system / 17” Hart racing wheels / KYB AGX struts, w/ upgraded anti sway bars / Rear brake conversion (front to rear, Brembo in front)
Jay- wakbrd99@aol.com
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22572, RE: how much horsepower from 12.5-1? Posted by Michael_97RS, May-08-02 08:05 AM
a 25 shot isn't worth it, retard the timing under spray and with forged internals shoot a 100 shot }> And they've pretty much covered everything, about 10-12% increase on what the motor would be at on stock compression, and eventually my motor will be 12.5:1+ compression ration motor with other goodies... :-)
Una salus victus. It's not about being invincible, it's about being ready; for anything.

Michael J. Kulaga e-mail: Michael_97RS@2gntDSM.zzn.com aol IM: MJKulga http://highlander.dsmpower.com/
Injen CAI, 55mm TB, Hooker 4-1 Stepped Header, GS-T Muffler, AFX UDP, S-AFC, 8.5mm Magnecor Wires, Crane Fireball HI-6DI2, SS Clutch Line, NRG Susp. Motor Mount Ins., FU/RU/RL STBs, TSW Blade 17x7.5, Bridgestone Potenza RE730 215/45ZR-17. Front KVR Cross-Drilled Rotors & Carbon Fiber Pads
To Be Installed: P&P Intake Manifold 1/2, P&P Milled Head, Rear Disc Brakes, Rear KVR Cross Drilled Rotors & Carbon Fiber Kevlar Pads, SS Brake Lines
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22573, RE: how much horsepower from 12.5-1? Posted by Dave_FL, May-08-02 09:57 AM
>>stage 3 clutch, with some nitrous, and a fully built head....I >wonder what type a 1/4 mile I would run? > >I don't think you will want to go with a stage 3 clutch. You >wouldn't be able to drive that thing on the street! Plus- I >hope you mean a 25 shot of nitrous. Your tuning window >narrows with 12.5 comp ratio and nitrous.
Most of us turbo guys get the stage 4 clutch and it works great. So a stage 3 would be very streetable.
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22574, RE: how much horsepower from 12.5-1? Posted by babybeclipse, May-08-02 12:50 PM
ya, but you turbo guys are notorious for blowing up clutches! I've seen too many pictures of MT in pieces.
I'd play it safe and start with a stage one and move up as your car gets faster.
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