bigger cams for a jeep liberty

[Bashgod]

any help? i think i heard something about 265-267 mm cams from mopar... ill check out.

 

[_UnLiMiTeD_]

why.....

 

[welby]

why.....

The most simple answer: a bigger cam makes more power.

http://auto.howstuffworks.com/camshaft.htm

bashgod: I haven't researched cams for the 3.7 personally but you might want to give the guys at http://www.krcperformance.com/krc/ a call. They only have cams for the 3.9l right now but they might be able to set you up with a custom regrind or point you in the right direction.

 

[JeepJeepster]

talk to kyliberty, hes knows all about that stuff..

 

[_UnLiMiTeD_]

yes i know what it does, i meant why for a liberty. Its no sports car, and a bigger cam will just hurt gas mileages, depending on how agressive one you get.

 

[Boilermaker]

talk to kyliberty, hes knows all about that stuff..

iirc, one of KY Liberty's posts said the Fastman might be able to help you with cams.

 

[Atrus]

Not necessarily true on both comments - it probably won't hurt mpg as much as you think (depending on the grind you go with), and actually you could regrind to give more power off the line.

I say kudos, check into it. It's a little strange coming from a 3.8L that has a TON of aftermarket to the 3.7L with nothing.

 

[Bashgod]

thanks guys. I want bigger cams because I want more power, bigger cams can be designed to give more low end power or top end power. personally i think my liberty needs more top end. I am slowy building up my jeep I have a full exhaust, new intake, with a Jet stage II chip, 93 octane gas, fastman throttle body on the way.

The liberty is no sports car and neither is a Civic, Integra, or Celica but how many do you see with 400+ horse power.

These upgrades are small steps to the supercharger i plan to install, after i get forged piston and new aluminum rods. I hope to run it at 15 psi with 400+ hp to the wheels... after my lease is up of course lol.

As far as gas mileage is concerned it is obviously a compromise im willing to make, more power needs more fuel...

 

[VTNomad]

Performance

If you're going for performance, why not go for the whole lot? Most people just slap on an intake and exhaust and stop there. To truly unleash the full potential of the engine, you'll need headers, cams, fuel injectors, throttle body and an underdrive pulley. If you want to supercharge it you'll need forged pistons. You'll also need to have the PCM flashed to remove it's limitations.

If the guy wants cams, let him have his cams. Hopefully he'll look into it and post what he finds out, so the next guy can benefit from it.

 

[tjkj2002]

thanks guys. I want bigger cams because I want more power, bigger cams can be designed to give more low end power or top end power. personally i think my liberty needs more top end. I am slowy building up my jeep I have a full exhaust, new intake, with a Jet stage II chip, 93 octane gas, fastman throttle body on the way.

The liberty is no sports car and neither is a Civic, Integra, or Celica but how many do you see with 400+ horse power.

These upgrades are small steps to the supercharger i plan to install, after i get forged piston and new aluminum rods. I hope to run it at 15 psi with 400+ hp to the wheels... after my lease is up of course lol.

As far as gas mileage is concerned it is obviously a compromise im willing to make, more power needs more fuel...

What year KJ do you have? If you have a mid year '03 or newer you will need major ****** work done,the 42RLE won't live behind that power.Also sorry to say you'll be needing way more than then forged pistons and rods,and new harden steel crank will be needed for the engine to last,and those are not cheap($2500+).The 3.7 is just not ment for high HP,for the money spent trying to get 400HP from a 3.7 you could swap in a 4.7 and do some light mods on that and be at your HP rating for probally less.Or if you want to get really fancy you could shoe horn a 6.1 HEMI in and get 610HP for $20,000(plug and play),but then to you would need ****** mods and rear end mods.

 

[Bashgod]

its a 2007, headers and all the rest of that stuff are on the list. the supercharger and future plans (years down the road) and by the time i have all the money I might want to do something else.

Calm down all you nay sayers, I appreciate the advice and am taking it into consideration but I really want to stick with the 3.7 as pointless as it may be. I would like the satisfaction of saying "yep a 3.7 v6..."

 

[tjkj2002]

its a 2007, headers and all the rest of that stuff are on the list. the supercharger and future plans (years down the road) and by the time i have all the money I might want to do something else.

Calm down all you nay sayers, I appreciate the advice and am taking it into consideration but I really want to stick with the 3.7 as pointless as it may be. I would like the satisfaction of saying "yep a 3.7 v6..."

But it would so much cooler saying----"Yep it's got a HEMI"----!!!!!!!!

 

[Bashgod]

ya but to say a 3.7 v6 just smoked your HEMI is something to be proud of, IMO more so than to say my Hemi is faster than your hemi. It would be cool though. My friend and i joke about that, we say things like "put huge cams on it to watch the jeep rock with the bad idle," or "floor it and watch the torque twist the chassis and blow out some windows and break the lock on the tail gate then watch it swing open, lol.

 

[offrovering]

what color is your jeep?

i heard yellow or red adds a few HP

what about yellow with red flames!

 

[indieaz]

I don't see the point either, more aggressive cams will only make sense at high rev's...which means you lose power (compared to the stock cams)/ poor running engine at low rev's. Which you use the most offroad...

If I had a V6 and bunch of $$$ I would go for bigger pistons...

That depends ont he cam grind and the setup and flow rate of the heads. You can increase your power down low or up top.

As for gas mileage...depending on how good the tune is and the aggresiveness of the cam you could increase that as well. Although it's probabl unlikely without proper headwork to match it up.

That said...I don' tthink i'd waste my time or money doing it. My guess would be the stock heads won't support much more power...and without a really good tuner your gas mileage likely WILL go down and i would be surprised if you gains more than 25-30 horsepower at the wheels.

 

[BlueJeep07]

Do it and have fun.

My advice would be simple. Use quality parts that you won't have to swap out later on. Dryflow intake (cold air if available), long tube headers (if available), Gibson exhaust with mandrel bends or other mandrel bend system (2 1/2" should be plenty big), Reprogrammed computer, and underdrive pulley (be careful of ASP).

After doing the easy bolt-ons you can decide to stop there or move up to forced induction.

That's what I'd do.

 

[indieaz]

Do it and have fun.

My advice would be simple. Use quality parts that you won't have to swap out later on. Dryflow intake (cold air if available), long tube headers (if available), Gibson exhaust with mandrel bends or other mandrel bend system (2 1/2" should be plenty big), Reprogrammed computer, and underdrive pulley (be careful of ASP).

After doing the easy bolt-ons you can decide to stop there or move up to forced induction.

That's what I'd do.

Forced induction, are you serious? I hope he's gunna at least put in forged pistons and rods first. But if you're gunna take apart the entire engine why not just swap it with a more powerful engine to begin with? I don't think longtube headers are made for the KJ - would probably need to custom make some. I beleive JBA makes some shorties though.

 

[Atrus]

From my limited knowledge on the 3.7, I'd think the biggest hurdle is from lack of PCM tuning. Cams and mechanical parts can be fabbed up.

I'm not sure on the capabilities of the 3.7, but there are GM 3800's (push rod 3.8L) that a supercharged that are running 11's in daily drivers in Regals and Grand Prixs. A properly force-fed V6 isn't anything to laugh at for sure.

 

[JeepJeepster]

I would start with the simple things first.

-Not much you can do with the intake. Drop in Amsoil or K&N is good enough.
-FastMan Throttle body
-Shift Kit
-Exhaust.. A muffler is about all you need..
-New PCM programmed by B&G..
-New torque converter from APS

THEN start thinking bigger..

 

[indieaz]

From my limited knowledge on the 3.7, I'd think the biggest hurdle is from lack of PCM tuning. Cams and mechanical parts can be fabbed up.

I'm not sure on the capabilities of the 3.7, but there are GM 3800's (push rod 3.8L) that a supercharged that are running 11's in daily drivers in Regals and Grand Prixs. A properly force-fed V6 isn't anything to laugh at for sure.

Right, but like you mentioned - PCM tuning. The GM 3800s have been around (since series I) for just over 20 years...and the following has lots of knowledgable people. Plus GMs tuning is hardly secret - I've truned F-Bodies and such myself - there's tons of information available on them and lots of community support. There is nobody out there tuning engines in KJs. For a good reason - there's really no market for it.

Fruthermore the 3800s came with forged pistons+rods from the factory and can take quite a bit of power.

Camshafts can be fabbed up for anything - it'll jsut cost some more for a custom grind (my last f-bod had a custom grind).