Truck mods

[Myril]

I tow my 215EC with a 2002 GMC 4x4 PU, 5.3L with 3.73 gears. It does a really good job, however, I was thinking about adding a CAI (cold air intake) to the engine. Have any of you performed this mod, and if so, could you tell any difference in performance and mpg?

 

[Lazy Daze]

CAI will do very little if you don't combine it with a better flowing exhaust/muffler. Buying a tuner to "re-tune" the engine will give you even more benefits (both power and economy), but the intake/exhaust should be done first. Just re-tuning may not do much if you can't get the air in and out faster/more efficiently.

 

[magster65]

CAI will do very little if you don't combine it with a better flowing exhaust/muffler. Buying a tuner to "re-tune" the engine will give you even more benefits (both power and economy), but the intake/exhaust should be done first. Just re-tuning may not do much if you can't get the air in and out faster/more efficiently.

True that. My '03 Ford F150 FX4 has the little 4.6 in it. I added the intake and it didn't do much other than make it sound like it was bogging when you put your foot into it. Then I added the catback exhaust and that made a huge difference... plus it sounds great now. I might put a chip in it one day but I'm happy with the way it is now.

 

[JUST PULLIN MY DINGHY]

CIA doesn't effect power or mpg just make more noise at most your lucky to see 2-5 hp on a dyno gas motor, diesels benefit more. A programer is where you'll benefit most even with stock exhaust .Cia and tuner will be enough, did this on 2000 f-150 4x4 with 35 inch tires picked up 1 1/2 second in quater mile time.Bully dog ,Hypertech slashback are good ones for that .Summitt racing makes a nice cat back system for a good price .

 

[MonacoMike]

I installed the K-N cold air kit on my 2500 Suburban. My around town mileage improved about 1 mpg, there was no effect on towing mileage. From a performance perspective acceleration was improved which is a help when towing a 10k trailer.

I am most puzzled by the responses of our friends, I owned the truck 5 years and 75k, we were close. I could feel the difference on acceleration. Have you guys done an install on a truck you knew well and drove regularly? Were your expectations to high? Its not a supercharger.

Bottom line for me is I would buy it again and recommend it to my friends.

MM

 

[Lazy Daze]

Have you guys done an install on a truck you knew well and drove regularly?

Done various combos on a few personal vehicles - Dodge 5.3L, GM 5.7L and 5.3L. Friends and relatives... more 5.7's and 5.3's. Lot's and lot's of HP/torque curve charts/comparisons/articles, too.

Does a CAI, by itself, help? Sure, it can't hurt. But, like mentioned above, the gains are minimal when dealing with a gasser. The most benefits won't be realized until the intake and exhaust are done and then combined with a tuner. But doing just one of those components doesn't yield much.

From the way I interpreted the OP's line of thinking, he's trying to decide if adding a CAI will be worth it (and make a noticeable difference) when comparing the gains against the cost factor. Since he's already happy with what he's got, in my opinion, it's not worth it since the gains are very minimal. To quantify it, generally speaking, adding a CAI will likely show a 2% or 3% improvement. I'm ball-parking those figures, but I'd bet they're pretty close.

However, one thing to take into consideration is the type of OEM intake currently on a vehicle. A poorly designed one would benefit more from a CAI than a better designed one. The GM 5.3L is decent enough to start with that the resulting yield, by adding a CAI, isn't that much.

 

[MikeOnBoard]

Ditto with Lazy Daze. My F150 picked up noticeable power with the CIA/exhaust package. One is pretty much meaningless with out the other. It's a good base mod. If you choose to... a lot of other mods can be done as well. All bolt on stuff.

 

[Go Aweigh2452]

1. Get a real truck.
2. Get a turbo diesel for towing.
3. Programmer or chip it... or both...



Nuf said...

 

[MonacoMike]

Done various combos on a few personal vehicles - Dodge 5.3L, GM 5.7L and 5.3L. Friends and relatives... more 5.7's and 5.3's. Lot's and lot's of HP/torque curve charts/comparisons/articles, too.

Does a CAI, by itself, help? Sure, it can't hurt. But, like mentioned above, the gains are minimal when dealing with a gasser. The most benefits won't be realized until the intake and exhaust are done and then combined with a tuner. But doing just one of those components doesn't yield much.

From the way I interpreted the OP's line of thinking, he's trying to decide if adding a CAI will be worth it (and make a noticeable difference) when comparing the gains against the cost factor. Since he's already happy with what he's got, in my opinion, it's not worth it since the gains are very minimal. To quantify it, generally speaking, adding a CAI will likely show a 2% or 3% improvement. I'm ball-parking those figures, but I'd bet they're pretty close.

However, one thing to take into consideration is the type of OEM intake currently on a vehicle. A poorly designed one would benefit more from a CAI than a better designed one. The GM 5.3L is decent enough to start with that the resulting yield, by adding a CAI, isn't that much.

K-N claims a 15hp increase with CAI on GM 6.0. Is there that much difference in air boxes on GM trucks? Will a free flow exhaust improve the torque band? Do you need a system or free flow mufflers?

MM

 

[OldSkool]

Just remember, what goes in must come out. Cat back systems will increase the efficiency of any improvements to the induction system. Cool air in, much like cooled fuel, will help atomize the mixture for a more complete burn but then getting the spent exhaust out is even more critical. Many engines see huge performance increases just by using custom exhaust.

It's not about bigger diameter but about routing and taking out crimps, restrictions and sharp angle bends that create vortexes in the exhaust and cause gas pressure restriction.

Here’s an interesting read but definitely not the last word on the subject.

I'll try to find a more complete discription on exhaust restriction and post it later in the thread.


http://www.thrashercharged.com/tech_htm/exhaust.shtm

 

[Lazy Daze]

K-N claims a 15hp increase with CAI on GM 6.0. Is there that much difference in air boxes on GM trucks? Will a free flow exhaust improve the torque band? Do you need a system or free flow mufflers?

MM

My guess is that you can answer your own questions?

EDIT: Disregard the above question.

Had a very nice and pleasant PM with Mike - things got lost/confused in translation in the above posts.

Mike, did the subsequent posts answer your questions?

 

[xravenx]

Many engines see huge performance increases just by using custom exhaust.

I have a 96 Chevy Z71 with a 5.7 Vortec (67,000 miles). From day one I could never spin the back wheels. I had a true dual Flowmaster exhaust installed a couple years ago and now I can easily spin the rear wheels. Since I already have the exhuast in place, would a CAI be worth it?

John

 

[ch435]

It seems every tuners first mod is cai. Its cheap and easy. Minimal risk of damage to engine, etc. Depending on ones setup, hp gain is around 5-15 hp at the wheels.

The next common mod is exhaust, for reasons as mentioned.

If one decides to "get a chip", or retune what you have, be careful! Don't let some fly by night place retune your vehicle. That's how you blow an engine, or lose a tranny. Stock parts can only handle so much power. Know their limits!

 

[JUST PULLIN MY DINGHY]

I have a 96 Chevy Z71 with a 5.7 Vortec (67,000 miles). From day one I could never spin the back wheels. I had a true dual Flowmaster exhaust installed a couple years ago and now I can easily spin the rear wheels. Since I already have the exhuast in place, would a CAI be worth it?

John

Yes since you already have the exhaust CAI is worth it there are a ton of aftermarket kits out there. Big name and cheapies you want a real cold air intake not just a filter hanging under the hood sucking hot engine compartment air.It should have some kind of sheild directing cold outside engine compartment air thats where the real benifit is .

 

[JUST PULLIN MY DINGHY]

Just because they advertise hp numbers dont mean there real world numbers. I never seen 10 or 15 hp gains at the wheels from a CAI. Those figures are way off those numbers are at the flywheel.You lose hp threw trans ,rears drive on dyno's tell the truth been there done it. Buyer beware.Just dont expect huge gains mpg should improve. Good luck

 

[Lazy Daze]

Just because they advertise hp numbers dont mean there real world numbers.

Another testament to this is that the published/estimated HP gains are typically the gains seen at high RPM's. This is simply due to the way that HP is calculated and that most engines make the most HP with high RPM's. This is of more importance to someone like a drag racer as the entire race is performed higher in the RPM band; plus the engines don't spend much time at that elevated RPM as the race is over quickly.

For those of us that are interested in towing a boat, the gains at a sustainable RPM are much more important (say somewhere in the 2500 to 3500 range for gassers). The gains that are seen in this lower RPM band are less than the published numbers.

The funny thing about HP is that, for trailer boaters, it doesn't really mean much. Torque is the key... how early the torque comes in and how flat the curve is. Now, this isn't quite apples to apples, but... my Suburban's engine only made 195HP (flywheel) in 1998 - probably about 150ish at the rear wheels. But, I'll out-tow gas engines making a lot more HP than that. With diesels (for those of you that don't already know that real trucks don't have spark plugs:smt001), the peak torque (which is also significantly more than a gasser) happens very early in the RPM band and then basically flattens out - it doesn't "spike" up and back down like a gasser.

Ditto... to Just Pullin's answer to Xravenx's question.

 

[boltman]

Ya'll just need to upgrade... To this... an F450 6.4 liter Diesel...Pulls 20k like it's not there.

Not even tuned up..Yet!!!
She's lovely isn't she.???

 

[avguy]

Ya'll just need to upgrade... To this... an F450 6.4 liter Diesel...Pulls 20k like it's not there.

Not even tuned up..Yet!!!
She's lovely isn't she.???

I agree.....sort of. I've got an '05 F150 w/ an edge chip in it. After a couple years driving it I've come to the conclusion that if you need more HP get a bigger truck :thumbsup:

 

[magster65]

Ya'll just need to upgrade... To this... an F450 6.4 liter Diesel...Pulls 20k like it's not there.

Not even tuned up..Yet!!!
She's lovely isn't she.???

... great towing capacity but we don't even have parking spots big enough for that sled! I only tow about 1% or less of the time so a vehicle like that makes no sense at all for me.
Nice truck though! :thumbsup:

 

[ch435]

Depending on your vehicle and setup, a 10hp gain is not that hard. And I am referring to the wheels, on a dyno, which is the best way to get accurate readings. But a good point was made in that the gain is at the top end of the RPM's, which is where very little time is spent in real world driving.