Rokko

iTrader: (2)

I guess I better get some headers to compliment my cam.

QTP's are on sale through 12/23.

Are the merge collectors really worth the extra 400+ bucks? How much HP do they make over the regular collector style?

WAHUSKER

iTrader: (4)

They say they are worth 10hp. Over what they don't say. But any of the 4 Grotty style headers will give you good power.

NataSS Inc

iTrader: (9)

YES, they are worth it.

Poik

Extra 400+ for different collectors? Damn! That's as much as I paid for my coated headers! If price isn't an issue, of course 10hp for $400+ is worth it, lol.

NataSS Inc

iTrader: (9)

Actually I think its a little more than 10hp. And if you think about it and LS6 intake is only worth a 10-15hp gain. and what do they go for new 350-400.00....Its all relative.

Rokko

iTrader: (2)

decisions decisions..........

02 extensions are required too, correct? found it, yes they are.

Ryan K

iTrader: (11)

Actually no, they are not worth **** if you are going to run a standard y-pipe / intermediate pipe. They are only worth 10 hp-ish when run in an open header-header extentions exhaust system. I ran the QTP headers and they have an issue with sealing the merge collector on the inside, that will throw off your O2 readings.

Ryan K.

Racehead

If you get the hi-velocity merge collectors then you should probably get the dual cutouts like I did to take full advantage of them. I haven't noticed any o2 sensor anomalys on my car ? Maybe they took care of that issue ? My headers are only about 6 months old ?

TwoFast4Lv

iTrader: (8)

What Ryan said

BTW good ones are $350-500 EACH!

ram-it

I would not buy them if I did not plan on stroking the motor down the road. On a stock cube motor I highly doubt you would get 10rwhp. Maybe 5hp at most if even that. If you look at there website I believe they tell you what kind of setup they were running to get that 10hp extra. Not apples to apples if you know what I mean. Then add to that it will not sound different and people will not be able to see it so spend the money else where.

Rokko

iTrader: (2)

Thanks for all the input everybody. I'm thinkin I'll save the 400 and maybe add another 200 to it and buy 150hp, if needed, depending on what the rules are for roll bars this season. It's still 1300+ for headers and y with cats.


Kooks and QTP's tuck up the best for clearance, correct?

ram-it

If I had it to do over again I would buy the QTP's and get them coated. I like the NO2 idea. Go for it!

WAHUSKER

iTrader: (4)

QTPs, Kooks, PPCs & FLPs tuck & perform the best. I would say the FLPs are the worst for performance of that group because they have smaller tubes. PPCs have a 3" y-pipe, but it's a ***** to assemble / install. Stainless will never rust, but ceramic coated looks better & is a skooch better at transferring heat.

ANY of them will need the i-pipe cut & welded to finish the job.

Racehead

I'm still a believer in hi-velocity merge collectors. Naturally I would say that since I have them However IMO too many racing venues use them WITH mufflers ( racing mufflers ) with good results for them not to work. How much hp is certainly up for debate, I'm sure it depends on the rest of the exhaust, the rpms your turning, and probably 4-5 other variables. Even if it only gives me 5 rwhp, that's 5 more than I had, and it's 5 that was achieved just by making my existing engine more efficient, rather than making it more radical. It's also 5 more that I'll have on top of any mod that I do. I can certainly understand someone not wanting to pay the price for them for the little gain 5-10 rwhp that you get. Since I have two 3" cutouts 18" from the collectors I'm hoping that it's given me at least 10 rwhp I haven't dyno'd since my header/ORP install so I'm looking forward to seeing what I've gained over the 338 rwhp I dyno'd before.

Yes Kooks and QTP's both tuck up very nice, I believe the PPC's do as well

ram-it

I hear what your saying Bill, but I do not believe on your car or my car the merge collectors would net a difference over 1-2rwhp. If you do not plan on increasing the cubes the extra $400 can be used better else where is my belief.

Tranzor

I say go for the merges to give yourself room to grow should you want to later on down the road... the new Edelbrocks come with high velocity merges already on them from what I understand, and they're much cheaper than the QTPs.

Plus, $600 ain't gonna buy you 150 hp... I've been looking seriously into a wet shot as well, and once you buy all the goodies (WOT switch, window switch, purge, remote bottle opener, bottle warmer, gauges & gauge pod, etc) it becomes more like $1200 in parts.

Racehead

Eric,
You're confusing the affects of header diameters with the affects of merge collectors. The size of your engine has nothing to do with the affectiveness of the collector. I can realize the full affects of a high velocity merges right now on my stock internal car and so can you. It's dependent on what your exhaust is like AFTER the merge. Increasing or decreasing the engine size doesn't affect the merges affectiveness at all.

What makes a high velocity merge collector work is the low pressure area that it creates behind the venturi. This low pressure area essentially "sucks" on the rest of the header increasing exhaust flow thru the collector. That's how the system works and any engine will benefit from this affect. You won't find a prostock or NASCAR car without one. You also will find them being used by the better teams in IMSA, SCCA, Road rallyes, Pikes Peak contenders. They are just now finding there way onto the street and because of the high cost they might not be the best choice out there for you, but they DO work. If you put a restrictive exhaust on your car, the exhaust restriction this adds backs up into the low pressure area of the high velocity merge negating it's affect .... in essence you now have a regular header again and if you paid $400 for high velocity merges, you just threw your money down the drain. Not because they don't work, but because you didn't understand HOW they work, and didn't design the rest of your exhaust to work WITH it.

Don't spend the money on them if you

1) Have cats on your car
2) Have an exhaust that's fairly restictive ( quiet )
3) Are tight with funds and are looking for the best bang per buck

If you can afford them then DO spend the money if

1) You have no cats ( Me )
2) Run an open exhuast ( Me, open Borla )
3) Have dumps ( cutouts ) right behind the collectors ( Me )

:off soap box:

WAHUSKER

iTrader: (4)

Great detailed explaination Bill. That expands what Ryan said earlier. It helps when people understand why they need to make certain choices for the setup they want. Which is why I went with the PPCs that do have cats, but also have a 3" y-pipe. It's my way of getting more flow & still maintaining my tree-hugger car.

Steve Goodwin

If you factor in the tire smoke you have been know to leave I believe that cancels out your emission equipment and voids the tree hugger approval.

Rokko

iTrader: (2)

Well, since I have cats and have to go through emissions, which are getting more and more stringent in our corner of the world, I'll be getting the regular QTP's and catted y pipe. Their y is the best I have seen. Very well designed for flow where the two singles connect at the y.

Anybody interested in Random Tech highflow cats and y pipe with very low miles on them? For years 2001 and 2002. They bolt right up to the stock exhaust manifolds.