Not arguing or antagonizing anyone here. I have seen you on numerous boards ripping the aftermarket. I agree that some stuff out there is worthless. I have also had personal experience with modifying my cars and seeing gain on a dyno and at the dragstripwith aftermarket parts. Your knowledge of motors and flow charteristics and the rest is a lot higher than mine I am sure. All I know is what I have done and seen work. I have never modded and dynoed the monte carlo so I have no first hand experience. I have modded and dynoed a LT1 Trans AM and a WRX. Both cars showed gains in rwhp/awhp on the dyno with cold air intakes. Exhaust and headers/down pipe also made significant gains. I am not trying to keep the argument going just trying to understand better. It is only when people with opposing views debate topics that we look at all sides. These discussions are healthy for the board if we can keep personal attacks out of it.

 

50 crank hp might be a stretch- but I bet it could be done with bolt ons. Look into doing high ratio rockers, and then check out if anyone makes headers for that engine yet. I know the LS1s can do that with a lot of bolt ons, I'm just not sure how possible it is with the LS4.

Honestly, you're out of my realm- the ls1tech guys would know your engine- what works and what doesn't a whole lot better. I bet they've already got some good threads on there about the LS4.

A lot to learn about what? What doesn't make sense to you about what I posted?

People only have 2 proven choices for exhaust power on the 3800: plog/3" dp or headers. plog/dp is preferred to those wanting to stick to cheap, easy basic bolt ons, headers are preferred to those wanting more.

As far as tuning goes- I don't see how you can down the tuning method that 99% of 3800 people use- a Powrtuner or HPTuners on a laptop. I also said that the handheld programmers are ok, but don't have near the adjustability for the same price. Lastly- the box 3800 pcm has been done for years and years with dyno proven gains. They're nowhere near a customized 1 off tune because they're way safe, but for someone doing only basic bolt ons that knows nothing about tuning and doesn't want to pay for a full on tune, they can get say 50% of the gain for 1/4 of the cost- and fix many problems at the same time (such as boost dump, top speed limiter, etc).

A plog/DP won't be any worse for streetability or mileage than headers- so I don't see the problem there. I didn't see a change in either on my basic bolt on gp.

As for tuning- sure you can really f up a tune doing it yourself if you just go changing things that you don't understand, but there are very simple guides to follow if one takes the time. If someone doesn't feel comfortable- that simply leaves either a box pcm or a custom tune. Streetability and mileage will be the same, if not better. I don't see how gas mileage out of PE is gonna change with a tune.

Please explain why any of it is 'track only'? If you don't want to mod your cars, then don't- seriously. People are in this thread to find out how to get more horsepower, so I am helping with what I am extremely familiar with- the 3800.

I hate to say it- but a lot of the people on this thread have 3800s, and that is what the majority of questions are about. I have the PT, which is what some of the big 3800 companies use to tune their cars. The other companies use HPT- which is essentially the same thing. I don't see how you can down this method though- I guess ZZP running 8s with their HPT tune must have been a fluke huh?

I'm not as much of a newb as you think I am- I have owned 4 3800 wbody cars, I currently have 3. I have played both sides of the game- one car I built from the ground up with no expense spared on anything, and on my gtp I have went the bare bones, minimal money/minimal time trying to get the best bang for the buck on a basic bolt on setup with a focus on retaining streetability and gas mileage. I have also tuned my 4 cars, plus 3 more local 3800s. Honestly, I think I have a slight bit more credability in a thread like this than you think I do.

 

The aftermarket is all about money.
People like Bumping are all about track.
Neither has any regard for anything outside of those realms and there is the middle.
95% here will never see a track.
A Larger diameter downpipe is going to kill them overall.
Those push torque curves up pretty decently to lose bottom to bottom mid to gain just a little up top.
You drive at 1800 RPM's and at 1800 RPM's lets say you stock are 100 ft lbs of torque. With the overly large pipe to be at 100 ft lbs is now 2500. Its gonna take more pedal for you to now maintain speeds and throttle change for whatever reason will take more effort. Loss of some mileage, but you gained .005 at the track you'll never be at.

Alot of these parts offer trade off and aren't all that it seems.

Cost has beeen brought in and is a very valuable part of this.
$200 for a downpipe on a otherwise stock engine is going to cost you much more than that in the long run and you'd probably never really use the increase it does offer.

$100 installed for a U bend delete you'd never now you did street wise. .02 in a 1/4 at best.

Headers offer all around , yeah more, yeah more difficult, but if you can get at it, have the tools to get a crusted downpipe off, headers will yeild you full rpm gains your *** can't miss and mileage WON'T suffer.

Rocker ratio same thing at a cost a cat back CAN'T match.

Those other offering only have abilities at high RPM's.
95%+ is driving where its un effectual.

So looking at it racing style.
Reading what I offered then looks like a anti christ.
But those going full out will have all ready known what to do.Street guys are eating it up wasting effort and monies thinking its gospel.

I NEVER said it was NOT going to offer anything, did I?
I just offered principles of theory.

 

I do have to agree about larger pipes and lower torque. On our Trans AM's people were putting on 3 inch exhaust and losing torque. With a 2.5 inch exhaust on the car I was able to produce a bigger torque and hp gains stock with just a catback. The only benfit to larger exhaust on the Lt1 was with forced induction and the associated mods.

 

BS BS BS BS BS- seriously posta dyno or some sort of proof on this exact engine. On a stockL36- yes a 3" DP is overkill- so get the 2.5" (like I said before), it is only slightlylarger than the manifold outlet which is ok because of the bends it has to have. On an L67, even bone stock a 3" DP is not going to push the powerband way up like you claim- trust me. I own a 99 gtp, and my first mod was a 3" downpipe with cat/ubend delete that I bought for $100 shipped. No noticeable bottom end loss, no worse gas mileage, and I dropped 2* of KR that my car had stock (meaning the car makes more power). You want a copy of my scans and gas mileage records? I mean c'mon man.

Seriously- if you're going to comment on these cars, maybe you should make them more specific to the 87 SS that you're used to, because you obviously have no personal experience with modding the 3800 that I'm referring to. You try to defy the logic that has been PROVEN in the 3800 community, when you admit that you have little 3800 experience.

I paid $100 used/shipped. How will it cost more in the long run? I bought a stainless DP, it will not rust through for years. My gas mileage was the same before and after with no noticeable trend up or down.

What are you talking about people not using the increase it offers? You simply press the gas pedal to the floor to see the gains. L67 guys can see gains as soon as they hit boost (could be as low as 30-40% throttle) by reducing KR. You don't have to go to a track to floor your car. If you never floor your car, then why would you be buying performance mods in the first place?

Downpipes incorporate the ubend delete- so you spend $100 in one shot (if doing the cat delete, more if you must have a cat), and it fixes all the problems in 1 shot.

Just to touch on this again real quick- you reccomend headers so much- well most all of the headers have a 3" downpipe included, so won't this push the torque curve way up like you say also? Or are headers magically exempt from this rule...lol

More expensive too- SLP's are $725 coated.

Or, one could follow my route picking up used items:
1.9:1 modded rockers $225, 3" DP cat delete $100, plog $100, 3.4" pulley $40, $10 copper 104 plugs, $10 180* drilled tstat, $100 for a box pcm or someone local to do a quick tune with their HPT or PT. edit- forgot a fwi for ~$50-60.

So thats $585 buying some stuff used (would probably close to $725 all new)- leaving you with more than $100 to spend on more mods- and also way more power than a headers only car. That setup should be right around 240 whp (+40 whp from stock)- no way would headers alone get you that much- maybe +20-25 whp tops.

rockers >>>> catback , just wanted to clarify that- the stock catbacks flow very well as they are.

Just want to reiterate, the only time performance mods are worth it is when you really get into it / floor it which is that other 5%. If you are not concerned with that 5%, then DONT BUY PERFORMANCE MODS. Since the OP is asking how to get 'more hp' I assume he is concerned about that other 5%.

 

Bumping stop with the 3800 bit, it doesn't work.
Boosted or NA, again that doesn't work either.
ALL MOTORS respond to mods the same way.
I got more time into tuning OBD2 than you might ever see lifetime.
The 87 is the wifes toy, something she bought, I work on, I buy the parts for and she drives.
I got rid of a Sonoma that I drove everyday that would make your GTP look ridiculous at the track.
I've owned more toys that you probably are old. This is not a new game, the rules have not changed.
Only extra gain you'll see boosted is because the motor makes more to begin with and these mods work in percentage against base. 3% on 100 h.p is 3 h.p., 200 h.p. same mod, same 3% is 6. If your cost justifying, maybe you can look at it like you do.
Also a header that has a collector output to be 3 inch is not going to see the same torque changes as a smaller outputted mani with a larger interm pipe. It was designed to work together, its flow characteristics in header designing were made for 3 inch's.


"Just want to reiterate, the only time performance mods are worth it is when you really get into it / floor it which is that other 5%. If you are not concerned with that 5%, then DONT BUY PERFORMANCE MODS. Since the OP is asking how to get 'more hp' I assume he is concerned about that other 5%."

Well you finally said it, not fully, but I covered the rest.
Some may actually want power not in the 5% you mention.
I was one of them looking to see what products were offered for the 3800 and don't drive around Fast And Furious style.

 

What doesn't work about it? I posted up a simple basic mod list that is the cheapest way to get ~300 crank hp/240whp and be right at the edge of 13s on an L67, and L36 guys have similar aftermarket. For some reason, you don't like the list- but thats life, its been done numerous times and is a proven combo. Just because a certain combo works well for a 32 Ford, doesn't mean its gonna work well on a B16 Honda- each has different strengths and weaknesses from the factory.

What doesn't work? The mod list I posted won't work on an L36 because you can't change a pulley if you don't have a blower to start with- hence why I said that their mods are a little different. I'm just helping with the engine I am most familiar with- and I generally reccomend L36 guys do a top swap and follow the same path for basic bolt ons.

What does this have to do with anything? I've got less than $1k in mods (and maybe 3-4 hrs labor)on a $6k car that looks decent- gets ~22-24 mpg city, and should be right at the 13.999 border. Its not the fastest car in the world- its not my track car, its just a simple DD. If I wanted to make it fast, I would spend actual money on it- but thats why I have my monte.

I didn't claim to know anything about other obd2 cars or other toys- who cares? I know the 3800, and to some extent the 3100- and I know wbodys.

When you come on here and try and rip apart all the mods that we have proven work- then you have to expect to be challenged. If you want to buy headers instead- and only have your car tuned by a professional system instead of our lowly HPT / PT then go ahead- but there are people here ona budget too.

Most of us are on a budget- hence why we're driving $1500-10000 cars, so bang for the buck is incredibly important.

That doesn't make sense to me. You're still flowing the same amount of exhaust either way- what difference does it make if goes through headers or manifolds first?

I understand the outlet of the factory rear mani is only maybe 2.5-2.75" or so, so it would expand a bit going into a 3" downpipe, whereas the header would be smooth 3" pipe, but I don't see why the manifold setup supposedly has these crazy hp losses down low where the headers dont (your terms- neither has been proven to be true). Not to mention, if a 3" DP was as bad as you say- why haven't the thousands of people that have bought one ever feel it? The only complaints I have seen are from L36 guys with few other mods.

That doesn't make any sense at all. The 3800s (NA and s/c) are very torquey down low as it is- plenty for driving around at low engine speeds. If you want more power the other 95% of the time you're not driving at WOT, then press the pedal harder. I don't see what is complicated about that. The mod list I listed will increase power from stock at all engine rpm. I have those mods on my car- and around town at part throttle, it feels just like stock, but is significantly faster at WOT from any engine rpm. If you honestly don't believe me- go over to clubgp and do some research for yourself- I'm not the first person to come to that conclusion.

 

Bumping, last post. If you haven't gotten by now, you never will.
You act like a 3800 is a completely different beast than anything else, it isn't. It will respond in the same manner as ANY OTHER motor and that includes tuning.
Velocity/scavenging is the most important aspect of exhaust tuning for maximum gain.
U bends, exhaust bends etc are just minor aspects, they do count in a overall scheme, but pretty much meaningless street driving.
Anytime, any motor, any air pump outlet system has a larger area within the outlet track before the last major restriction is SLOWS EXHAUST GASES, DISRUPTS SCAVENGING.
I NEVER EVER said a gain is still not found, hence your repeated statements of PROVEN.
You still gained, that isn't debated, you lost out on even better gains had you done it right as I stated and implied.
You just see gains, I see what could have been.
The header sets in question AREN'T smaller in output than the next pipe, of velocity/scavenging problems WILL NOT EXIST.

Then being on a budget, all cots must be looked at as a total package.
What you've picked doesn't pay off across the board.
You say you want faster press the accelerator pedal down more.
I and others want not to press it as far as you say.
We want the modification to pay monies back for what was paid out.
If the motors and its new performance modification don't pay back something in mileage, then we aren't using it, hence a waste in monies unless we show it and it gains a looks appearance.

CIA only pays dividends, still highly debatable in top rpms.
Larger downs, u bends cat backs, same deal.
Tuning as you hand held for, highly debatable still, same deal. Only thing here a normal driving person can really take advantage of is, limited torque management adjustments, code readability, tire size changes.

Headers and rockers pay dividends across the board, at any pedal effort.

Any informations I have given were for all to read so they could see both sides of this debate and make their own decisions without it being totally one side skewed with no explanation and be a Nike ad.

 

Wow. After reading the all the jargon and "logic" you've thrown in your posts I started forming an opinion of your experience in the performance field. That quote just summed up and confirmed my beliefs.

Every engine is different and DO NOT respond to mods in the same way. Whether is is a metal head gasket tolerance issue or the way parts match up each engine is different and responds differently.

Here are some simple facts that you can either just accept, or you can spend 1000+ hours researching between here, mymonte.com, and clubgp.com. Otherwise try these yourself and you will scratch your head and be confused why your "logic" doesn't work.

Facts:
The Ubend is a restriction - removing it will increase performance and gas mileage.
The CAI offered by reputable know dealers in the 3800 community do improve performance.
There are many other less expensive ways to increase power over headers. EG Rockers or Cam.
Larger throttle body's do increase Horse power.
Catbacks are next to useless on the 3800 supercharged vehicles as they make less than 5 hp until you have crack 300 hp. Then it becomes benificial. Most people do it for the sound. Read the exhaust posts and you will see it is all about the sound.

Having your car tuned with a DHP or HPTuners software program on a laptop is one of the best mods you can do. There are multiple records of people that have increased their horsepower not by the 2-3 degrees max timing you stated but more on the lines 5 degrees.

This disregard for aftermarket parts just irks me when I consistanly see people (including myself) see expected results. Finally on the lack of respect on tuning, you really need to educate yourself a bit better. Making blanket statements.... I can't even comprehend anymore how dumb that is. The last person I remember doing that was George Bush with his "you are with us or against us" speech.

Regarding tuning, head over to clubgp and you will find quite a few people that have increased their Horse Power by 20+ and I've heard of people hitting as high as 45 hp. This is not a company reporting this, it is an actuall person with no agenda. Other bonuses have been people that have converted over to E85 and INCREASED their gas milage, others that have lowered from 91 octane to 87 and increased performance and gas mileage a little bit, and finally one report where a member went to 87 octane, 13 second 1/4 mile and is getting 35 MPG on the highway up from the stock 29.

So yeah, I can see where tuners are worthless and completely abandoning these real life instances.

 

I then say to you.

I will agree on the theories end, that any bend in the system is a restriction of some sort.
Just using everyday givens, it isn't much of one at all. Most cat backs are saying 5-7 h.p. or up to 10 at times. Headers and other exhaust mods the same ordeal. Now your talking about a lot more bends and other restrictive ideals much more so than just one simple bend, which bends themselves have been proven to yield maybe 1 h.p. per.

How much does it give?
Not one post I have ever seen deals with that topic straight up. Other mods were performed at the same time, so.
Just U-bend, nothing else, lets see some data that disproves exhaust theory which says minimal.

CAI's and reputable companies? K&N is not reputable?
I could show you hoards of posts that show K&N systems increasing IAT readings.
Was it the Wiz units as a whole that added the so-called gains, or was it filter medium type that did it all?
Can you show me IAT temps, MAF readings along with MAP ones that show these systems really are what they are advertised to be? And not using the data from these makers?

Headers, well I guess you didn't read my posts as they were intended did you?
I said things like headers, cam changes, rockers etc are the things you should be targeting for real performance gains on a costability ideal.

And now you say catback are useless unless!
Well exhaust 101 would tell you as h.p. is increased due to a larger volume of air entering the more, which play hand in hand, then you really need to increase exhaust size in order to grab every available h.p. that the now too small a system isn't allowing.

Now your last sentence regarding AGENDA.

Oh believe me, you all have said I have a agenda with these posts.
Well as I play devils advocate, for years people have done it the other way to a much greater degree.
You get caught up in the Jedi mind game, you buy what the Jedi mind trick has told you to buy, believe me due to human nature these days, 98% will say it works. They DO NOT want to be 2% of the honest people whom others think are stupid because they couldn't find anything honestly.

You know how many events I've gone to and seen these dot com stickers on, ask some questions, find out there screen names and then find out how well they "type" versus what they really own? To me that has been PRICELESS!

The after market has done some great things, but they also and never forget are in business to make money and thats done at all costs.
If they were so pro US guys, then why do some of these W body shops sell junk.
Old Casper trickers that do absolutely nothing and such?
Where is there store?
Where is there testing labs?
Most all internet such dealers are nothing more than a drop ship with a web page.
Some are a little more than that. Once members, seeing a want, sometimes for good, sometimes for pure profit now back yarding this stuff. Thats why you don't see CARB# applied, to them, the cost is considerable to the write off.
I know, I used to do it myself for 8 years with the S truck guys!!