Flashpaq/Exhaust/CAI?

[Dr. Evil]

New member here. 2010 JK 6 speed manual with 3.21 gears. It is strictly a local daily driver. 1.5" RK springs (about 2.5" lift) with 33x12.50 Duratrac's, as well as some other suspension pieces. I just received a Superchips Flashpaq and aFe exhaust http://www.4wd.com/Jeep-Engine-Performance/Mach-Force-XP-Hi-Tuck-Cat-Back-Exhaust.aspx?t_c=74&t_s=49&t_pt=3383&t_pn=AFE49-46208. I am just looking to get a bit better throttle response and maybe some hp and mpg increase. Currently getting in the mid 16's local and 17+ on the small amount of highway driving I do. I understand not to expect miracles. For my usage, didn't want to spend $1500 - $2000 (parts+install) on gears. I was thinking about this CAI http://www.4wd.com/Jeep-Engine-Performance/Momentum-GT-Sealed-Stage-2-Si-PRO-DRY-S-Intake-System.aspx?t_c=74&t_s=6&t_pt=4555&t_pn=AFE51-76203. On the forums I am on, most basically HATE CAI's on the JK. Since I don't off road, I am not concerned about water, dust, etc. The general consensus is that they are a waste of money, can damage the engine over time and one should remain stock when it comes to the air box. Most vendors as well as aFe think otherwise but I hope it is not just because they stand to profit off of them. Finally, if this gets installed, is there any benefit to this throttle body spacer http://www.4wd.com/Jeep-Engine-Performance/Silver-Bullet-Performance-Throttle-Body-Spacer.aspx?t_c=74&t_s=6&t_pt=5708&t_pn=AFE46-35002? Can you folks please give me your perspective on the CAI and spacer? Thanks ahead of time.

[Pznivy]

I'll get my shot in before the experts arrive.

With 3.21s, your plan should be weight. You'll suffer from piggy gears if you add too much weight to this Jeep. The first of these mods your talking about should be the intake. AFE's is good. you'll get better sound and throttle response.

People who say they do nothing are wrong. For the 300 bucks, your Jeep will sound better, and feel better. The exhaust I care for less. If you only buy one, do the intake.

[Yoinkers]

Welcome New Guy!

I like a throttle body spacer and intake also. Exhaust is more of a personal choice. Remember chrysler spent millions developing the JK's exhaust with the pentastar. I doubt these aftermarket companies have improved it.

If you gonna do an exhaust, make sure its one that barks when you floor it, but can be quiet also. I've been looking for one that works like the corvette dual mode, but have not found it.

[JeepLab]

X2 on Pznivy's focus on WEIGHT.

If you don't want to gear, you should stick with keeping the weight down. These air flow mods will make your stock jeep nicer to drive, but will not save you from the performance decrease you should expect if you do steel bumpers, flares, etc.

If you were asking me about what sort of overall plan you should try for and NOT change those 3.21s, Id say your pretty much there. 33s. Stock bumpers, no winch. A stock jeep looks beautiful, and without the extra weight, yours will perform better than stock with the air flow pieces your talking about.

Intake first is the rule, if you can, drive it like that for a week. THEN do the exhaust. I like listening to the engine better than listening to the exhaust. Keep the stock exhaust on and do the intake and you will see what I mean. Then do the exhaust after, and keep the option in your pocket to go back to stock if you feel like it.

[gbaumann]

Welcome Dr. Evil.

X3 on WEIGHT. Cutting weight is like adding horsepower. I love the mods on my jeep but if I could shave several hundred pounds off my truck it would be great (Ross you should start a weight saving thread. Let's have a JL weight loss contest!!). Save the cost of exhaust. Unless you can open up breathing from the heads back there aren't big gains to be had. I have an AFE CAI on my 3.6 pentastar. I didn't install it for HP or throttle response. I did it for sound.

The motor can only burn what it breathes. Like all of us you're at part throttle most of the time. In our case the tune will determine air/fuel and the TB will meter air flow which together create a charge for the cylinders and dictate horsepower. It's the same air flow wither you have a CAI or TB spacer or not. There's no getting around the throttle plate (if you do, then there's no getting around intake/exhaust valve size, which if you do there's no getting around bore & stroke, and so on and you can see where we're headed until there's no getting out of the doghouse when our wives figure out what we've spent).

Response can be improved with the CAI and TB spacer if that's the goal. The flashpaq program, if it has an aggressive timing table and air/fuel table, coupled with 93 octane fuel can certainly make a change. It can make a different mix of fuel for a given volume of air and adjust timing to ignite it a more efficient time.

[UselessPickles]

I vote "NO" on the throttle body spacer. I have not been able to find any evidence that they do anything at all for modern port-injected or direct-injected engines. The original theory behind throttle body spacers was to give more distance/time and/or create turbulence for the air/fuel mixture from the carburetter to mix more thoroughly before entering the cylinders. From what I've read online, this actually did improve performance on older carburetted engines with the carb/throttle body mounted directly on top of the engine with a small intake manifold.

The Pentastar has its throttle body mounted on a large intake plenum, then then has an intake runner going to each cylinder's intake port. The fuel injectors are in the lower intake manifold, inside each individual runner, very close to the intake ports. A throttle body spacer will have no impact on how the fuel mixes with the air, and will have very little impact on the volume of the intake plenum. The intake plenum itself is likely already acoustically tuned to enhance airflow at certain rpm ranges. A spacer could actually make things worse at those rpm ranges.

Some more reading material about throttle body spacers:
http://www.tundraheadquarters.com/blog/stay-away-from-throttle-body-spacers/


I've used a tuner (Diablosport) on a stock jeep, running the 93 octane performance tune. It definitely improved low/mid-rpm throttle response. I think a tuner is worthwhile especially if you also plan to change tire size and can take advantage of its speedometer calibration features.

I have not used a CAI, but the general consensus seems to be that the sound is the most significant change. If the sound makes you happy, and you don't splash through deep water, then go for it, but don't expect big performance gains.

I think all of these options (tuner, CAI, exhaust) more subtly enhance throttle response rather than significantly improving full throttle acceleration. If you like the noises they make, then the sounds combined with improved throttle response will overall make driving more enjoyable. Just don't try lining up against a mustang thinking you'll win :)

[Pznivy]

Welcome Dr. Evil.

X3 on WEIGHT. Cutting weight is like adding horsepower. I love the mods on my jeep but if I could shave several hundred pounds off my truck it would be great (Ross you should start a weight saving thread. Let's have a JL weight loss contest!!). Save the cost of exhaust. Unless you can open up breathing from the heads back there aren't big gains to be had. I have an AFE CAI on my 3.6 pentastar. I didn't install it for HP or throttle response. I did it for sound.

The motor can only burn what it breathes. Like all of us you're at part throttle most of the time. In our case the tune will determine air/fuel and the TB will meter air flow which together create a charge for the cylinders and dictate horsepower. It's the same air flow wither you have a CAI or TB spacer or not. There's no getting around the throttle plate (if you do, then there's no getting around intake/exhaust valve size, which if you do there's no getting around bore & stroke, and so on and you can see where we're headed until there's no getting out of the doghouse when our wives figure out what we've spent).

Response can be improved with the CAI and TB spacer if that's the goal. The flashpaq program, if it has an aggressive timing table and air/fuel table, coupled with 93 octane fuel can certainly make a change. It can make a different mix of fuel for a given volume of air and adjust timing to ignite it a more efficient time.


^^^ This guy gets it.

Other forums are about heavy armor and huge pointless tires. At JeepLab, The attitude is. KEEP IT FAST!

Armor is pointless!

Avoid Steel anywhere you can!

Our jeeps are cars! A fast car beats a slow car every day of the week!

We don't want the trucks to be pigs and then say "hey its a jeep, performance cannot be good" That's crap! BB is a rocket. Sweet pea is a rocket. Jesse's Girl is a rocket. All putting down 0-60s as fast as a Supra Turbo. (supra did 5.5 in the nineties)

Have that AND climb anything? Thats the goal.

Rant over. (I hate heavy jeeps. can you tell?)

[Dr. Evil]

Welcome New Guy!

I like a throttle body spacer and intake also. Exhaust is more of a personal choice. Remember chrysler spent millions developing the JK's exhaust with the pentastar. I doubt these aftermarket companies have improved it.

If you gonna do an exhaust, make sure its one that barks when you floor it, but can be quiet also. I've been looking for one that works like the corvette dual mode, but have not found it.

Thanks for the welcome. I don't have the Pentastar engine since my JK is a 2010. Most folks that comment base their opinions on the 2012 and up engines. I believe it is different for my 3.8. The exhaust I linked in my OP has a nice sound but not too loud, which is one of the reasons I bought it.



X2 on Pznivy's focus on WEIGHT.

If you don't want to gear, you should stick with keeping the weight down. These air flow mods will make your stock jeep nicer to drive, but will not save you from the performance decrease you should expect if you do steel bumpers, flares, etc.

If you were asking me about what sort of overall plan you should try for and NOT change those 3.21s, Id say your pretty much there. 33s. Stock bumpers, no winch. A stock jeep looks beautiful, and without the extra weight, yours will perform better than stock with the air flow pieces your talking about.

Intake first is the rule, if you can, drive it like that for a week. THEN do the exhaust. I like listening to the engine better than listening to the exhaust. Keep the stock exhaust on and do the intake and you will see what I mean. Then do the exhaust after, and keep the option in your pocket to go back to stock if you feel like it.

I don't have stock bumpers. I have front and rear Or-Fab bumpers with no winch. I have the tuner and am picking up the exhaust tomorrow. I haven't decided on the CAI yet which is why I started this thread. Your post is interesting since most people have recommended if it was between the exhaust or CAI, they would do the exhaust (along with the tuner). I am not that picky that I care about where I hear the sound from, whether it is the engine or exhaust. The exhaust has a nice sound, could provide a better feel and is lighter than stock which based on your comments is definitely a plus. Now I just need to decide if I should go for the CAI. I don't see a down side to it even if there isn't a huge performance plus. I'll take anything I can get I guess.

[Dr. Evil]

Our jeeps are cars!

Say that on Wrangler Forum and prepare to get SLAMMED!:eek:

[Dr. Evil]

People who say they do nothing are wrong. For the 300 bucks, your Jeep will sound better, and feel better. The exhaust I care for less. If you only buy one, do the intake.

Actually, $252.99.:) Already bought the exhaust, just deciding on the CAI.

edit: just purchased it.

[Dr. Evil]

The Pentastar has its throttle body mounted on a large intake plenum, then then has an intake runner going to each cylinder's intake port. The fuel injectors are in the lower intake manifold, inside each individual runner, very close to the intake ports. A throttle body spacer will have no impact on how the fuel mixes with the air, and will have very little impact on the volume of the intake plenum. The intake plenum itself is likely already acoustically tuned to enhance airflow at certain rpm ranges. A spacer could actually make things worse at those rpm ranges.


Pickles - does this paragraph also apply to the older 3.8 engine that I have? No Pentastar for me.

[JeepLab]

Actually, $252.99.:) Already bought the exhaust, just deciding on the CAI.

edit: just purchased it.

How do you like the way your jeep drives now? before changing it around? Does it feel slow?

Is sluggish performance whats making you look to engine mods to get back some power you've lost?

[Dr. Evil]

How do you like the way your jeep drives now? before changing it around? Does it feel slow?

Is sluggish performance whats making you look to engine mods to get back some power you've lost?

I would say there is a bit of a lag, if you want to call it sluggish. It is hard to say exactly because I do local daily driving and forgot what it was like when it was stock. Sluggish on lower gears and low end I would say. Not terrible, but I figured it was worth a shot to get some more pep and response. I suppose if I did a side by side comparison to a stock one or the 2012 and up I would probably be a bit disappointed in mine but hopefully I will get what I am hoping for from these mods.

[JeepLab]

I would say there is a bit of a lag, if you want to call it sluggish. It is hard to say exactly because I do local daily driving and forgot what it was like when it was stock. Sluggish on lower gears and low end I would say. Not terrible, but I figured ir was worth a shot to get some more pep and response.

what makes you hate the idea of gearing it?

[UselessPickles]

Pickles - does this paragraph also apply to the older 3.8 engine that I have? No Pentastar for me.

Yeah, same general design for the 3.8. And pretty much any engine from the last 20 years.

[2k13jk]

A throttle body spacer will give you absolutely zero gains on a fuel injected motor

[Dr. Evil]

"what makes you hate the idea of gearing it?"


No hate here. I just don't have the $1500 - $2000 nor do I feel that with my usage of local daily driving , no off roading, minimal highway and 9000 miles per year warrants the expense. If I can get a little more throttle response, mpg's and some punch, I would rather spend at least half the amount with the bolt on's. I get the up side to re gearing. Just feel it may be overkill for my needs. I look at it this way. It is relative to what my JK is now. With the bolt on's, I believe I will have a JK that rides, acts and feels different in a positive way. Now, if I compared it to another JK with re gearing, would I be jealous and realize the improvement over my bolt on's? Well, as long as I don't do that to myself, I won't know what I could be missing and therefore I will be satisfied with my plan. Again, it comes down to cost vs. usage vs. coming up with a happy medium to get a different feeling/riding JK. Some may not agree with my logic and I get that. This just seems right for me at the present time.

[UselessPickles]

A throttle body spacer will give you absolutely zero gains on a fuel injected motor

... except for throttle body injection systems. Basically the early EFI systems that were a direct replacement for the carburetter (and modern kits for upgrading old muscle cars to EFI).

[JeepLab]

"what makes you hate the idea of gearing it?"


No hate here. I just don't have the $1500 - $2000 nor do I feel that with my usage of local daily driving , no off roading, minimal highway and 9000 miles per year warrants the expense. If I can get a little more throttle response, mpg's and some punch, I would rather spend at least half the amount with the bolt on's. I get the up side to re gearing. Just feel it may be overkill for my needs. I look at it this way. It is relative to what my JK is now. With the bolt on's, I believe I will have a JK that rides, acts and feels different in a positive way. Now, if I compared it to another JK with re gearing, would I be jealous and realize the improvement over my bolt on's? Well, as long as I don't do that to myself, I won't know what I could be missing and therefore I will be satisfied with my plan. Again, it comes down to cost vs. usage vs. coming up with a happy medium to get a different feeling/riding JK. Some may not agree with my logic and I get that. This just seems right for me at the present time.

Understood. And you did think it thru obviously.

Gearing is more than just the expense, its a roll of the dice with a gear job. Most invasive thing we've done. I think its even more invasive than the supercharger. The problem is that its a nightmare to correct a gear problem.

If you read "the truth about gears" you'll see my own case of problem gearing. Good yukon gears, a less good gear install job where i tried to save some money. Ended up doing it twice.

[Dr. Evil]

Out of stock on the CAI so I will wait. Just going with the tuner and exhaust for now. Maybe in the spring/summer I will do the CAI.

[WhiteRavenRR]

Welcome to JeepLab. Seems that there is finally someone other than myself who has the 3.8. I run 35's with a 2.5" lift and I use a Flashpaq Tuner. This is my daily driver but it also sees the earth in its natural habitat on occasion.

The Flashpaq will help out some but it's no substitute for regearing. I didn't buy a Jeep to go fast. I would be happy with just not loosing power on hills. The Flashpaq still doesn't overcome that. It's a relative minor solution for a bigger issue.

The exhaust is only going to let out what the engine is taking in. Aftermarket exhaust will be more streamlined and let out the exhaust more efficiently while maintaining proper back-pressure.

Just remember, no matter which route you take, you are driving a billboard.

[Dr. Evil]

Welcome to JeepLab. Seems that there is finally someone other than myself who has the 3.8. I run 35's with a 2.5" lift and I use a Flashpaq Tuner. This is my daily driver but it also sees the earth in its natural habitat on occasion.

The Flashpaq will help out some but it's no substitute for regearing. I didn't buy a Jeep to go fast. I would be happy with just not loosing power on hills. The Flashpaq still doesn't overcome that. It's a relative minor solution for a bigger issue.

The exhaust is only going to let out what the engine is taking in. Aftermarket exhaust will be more streamlined and let out the exhaust more efficiently while maintaining proper back-pressure.

Just remember, no matter which route you take, you are driving a billboard.

Thanks for the welcome. Yeah, there are a few of us 3.8 dinosaurs lol. I totally understand the flashpaq is not a substitute for gearing. I am not meaning for it to be. I also didn't buy the Jeep to go fast. As a matter of fact, I traded in a Mini Cooper with the supercharged engine for the Jeep. In saying this, that doesn't mean I wouldn't like to get all the performance out of it that I can WITHOUT re gearing. Not too many hills here in the Northeast so that isn't an issue.;)

[Dr. Evil]

So I have the Flashpaq and the aFe exhaust. Nothing installed yet. It may be a week or two until I install the exhaust. I am wondering how I should proceed from here.

1) Install the Flashpaq now and then install the new exhaust later.

2) Wait until I install the exhaust and then install the Flashpaq.

If I do #1, would I have to uninstall the Flashpaq and then re-install it again after the new exhaust is installed?

[UselessPickles]

Go ahead and install/enjoy the Flashpaq tune now.

When you install the exhaust later, just follow this procedure to force the computer into "quick learn" mode. It will basically clear out long-term fuel trim memory and re-build the fuel trim memory more aggressively than normal (probably other things I don't know about as well)l: http://www.quadratec.com/jeep_knowledgebase/article-89.htm

[Dr. Evil]

Go ahead and install/enjoy the Flashpaq tune now.

When you install the exhaust later, just follow this procedure to force the computer into "quick learn" mode. It will basically clear out long-term fuel trim memory and re-build the fuel trim memory more aggressively than normal (probably other things I don't know about as well)l: http://www.quadratec.com/jeep_knowledgebase/article-89.htm

Thanks Pickles (you aren't useless lol). Besides this, would I have to reinstall the flashpaq?

[UselessPickles]

No need to re-install the flashpaq tune after adding exhaust. All the included tunes on the Flashpaq are for "stock or lightly modified engines".

Same tune will work with or without CAI and exhaust. You could even skip the computer reset procedure, and it would eventually adjust fuel trims as needed. Resetting just makes it happen more quickly, and may reset/relearn other important things as well. I haven't been able to find any details on what exactly the reset procedure accomplishes.

[Dr. Evil]

No need to re-install the flashpaq tune after adding exhaust. All the included tunes on the Flashpaq are for "stock or lightly modified engines".

Same tune will work with or without CAI and exhaust. You could even skip the computer reset procedure, and it would eventually adjust fuel trims as needed. Resetting just makes it happen more quickly, and may reset/relearn other important things as well. I haven't been able to find any details on what exactly the reset procedure accomplishes.

Thanks. So are you saying that resetting the computer has nothing to do with the flashpaq and therefore doesn't negate the original flashpaq install prior to the exhaust install? The flashpaq install is still there after computer reset? Sorry for the questions. I am just new at the whole tuner concept.

[UselessPickles]

Correct. Resetting the computer does not remove the installed tune. It only clears out some "learned" memory and puts the computer into a "quick learn" mode to re-learn the stuff that was reset.

[Dr. Evil]

Correct. Resetting the computer does not remove the installed tune. It only clears out some "learned" memory and puts the computer into a "quick learn" mode to re-learn the stuff that was reset.

Got it. Thanks man!

[JeepLab]

Give us a pic of your rig!

[Dr. Evil]

Give us a pic of your rig!Over the summer without my hard top. Also replaced the grill inserts in these pictures with an aftermarket black grill guard similar to gutter guards.142214231424