siffert

Why do many headers have spikes and some dont? The spike is a collector with an actual spike welded into the center of the collector at a point where the four tubes converge. The spike guides the flow to the center of the collector and that is supposed to increase flow and add hp.

I know LG Pro's have merge collectors. I wonder why they dont have spikes in their collectors, while others do. Anybody know why? I know Kooks and AR headers have spikes with their merge collectors.

LG Pro with pinched merge collector and no spike:



My Kooks 6600-EX 1 3/4 Jet Hot coated headers with spiked merge collector with no "pinch":



American Racing headers with pinched merge collector with spike:



Cheap Chinese Clone with off-center spike and the color of the stainless already showing discolor and possible rust:

TommyV

Maybe it reduces torque.

runutzzzzz

Cost? A dollar is a dollar!

LS1LT1

Could be.

glenB

This is strictly speculation on my part but I base it on intake tuning technology.

I believe the spike is used to give the effect of a longer tube without actually using a longer tube. It continues the separation of the gas flow prior to merging in the collector. This is the same effect of runner extensions in intakes. The extension doesn't extend top to bottom but in a 'D' shape at the port entrance.

8850

siffert,

With that 1 7/8" straight collector Kooks headers and the spike I ran an 11.80 @ 118.62 mph in warm weather (77*) with only other mods an Xcelerator and tuning. I would have ran 11.5s the only time I've been out in cold air had I been able to hold traction. I had my best ever 60' going but on the 1-2 I lost traction and hit the rpm limiter.

Can't say if the merge is better than the straight but don't think the straight is hurting power terribly much.

By the way, my headers are not blue inside. My photography abilities is somewhat limited. Those had been ported to remove the excess weld build-up.

dennis50nj

i know with the 1 3/4 KOOKS LT i went 11.14 with a low 1.54 60 ft. in bolt/on form only thanks George

8850

With your converter it becomes a whole new ball game. A properly sized stall converter is worth .6-.7 improved et.

dennis50nj

they are available for your car

NavyC4S

Kooks, obviously being the superior product has them.

0Louis @ LG Motorsports

Both systems perform great. Both companies are great companies. If you drag race, you might see a tenth more with the kooks in the 1/4 mile, but the seat of the pants feel from the LGs on the street might appeal to another consumer.

In the end, its all about your decision, and if what you have on the car performs the way you want.

Back in the day, we ran spikes. We found them to be worth 1-2 hp, however the decision was made that in order to keep pricing in line, we needed to leave them out. Basically, the spike could be chalked up to dyno variances and we opted to leave them out of our program.

The collector choice is important too, make sure you look at the total package when picking your parts. A stamped, non merge collector with a spike will produce less HP than a merge with out. That I do know, as we tested that back to back quite some time ago, which is why we have a merge style collector. I know Kooks might have recently moved to that style collector, but I do not know.

Either way, you cant go wrong

andreas g.

Actually it's orginal name was a "pickle fork" designed by ballenger headers back in the 1960's. The theory is simple, the space the fork takes up in the collector would be otherwise dead air space which would slow for a moment the exhaust velocity. By having the fork in place the exhaust velocity is maintained improving the overall performance of the header. Pickle forks are found in headers with long collectors like Kooks. I have Kooks. LG gets the job done with longer primary tubes and a merge collector. They both work well. I guess it's just a matter of preference. Actually ballenger himself made a custom set of headers for my 1985 C4 that had a 383 in it. then he moved from orange county CA were I live to Arizona. He was still working last I herd.

siffert

Interesting, thanks for the info!

0MarylandSpeed

Kooks C6 headers have a Stamped merge collector...it just is not as agressive a pinch, and does not have a Megaphone on the other end of it like some competitors.

LS1LT1

Just an FYI, many believe that a merge collector must be specifically sized and tuned to each individual motor/power output situation to be completely effective, that there is no 'one size fits all' way of adding them on and getting better results.
Yes, most high dollar/high end race teams (NASCAR etc.) do use merge collectors on their headers but there were also weeks/months spent testing and R&Ding various combinations to see which design worked best for those particular motors.
Straight collectors might actually work better on some cars then the 'pick one and hope it works' type merge collectors that are being provided.
But they do look cool.

0MarylandSpeed

Actually...these pictures best show how Kooks does merge collectors. These pictures I just took are of a standard 1 3/4" GTO header next to a 1 3/4 x 1 7/8" stepped "Signature Series" header. Kooks uses a stamped merge that is cost effective...but their design is also more conservative in that it does not "pinch" the airflow as much...which could hurt exhaust velocity. The 1 3/4" header (on the right) has a standard collector..the stepped header (on the left) has a stamped merge similar to what is standard on the C6 headers like 6600-EX. All Kooks headers have spikes in the collectors.





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siffert

Thanks much for clearing that up!!! Those pics show clearly that the Kooks has a spiked merge collector (which I originally thought as straight) though like you say, its not as "pinched" as the others. Which explains why in the AR and LG pics above, looking down thru the collector the 4 individual tubes appear partially obstructed when taking a picture.

siffert

Thanks for the info and clearing that up for me!

Ragtop 99

Let me start by saying that Kooks makes a fine product and your pictures are very helpful. It was tough to see the merge collector on their website photos.
A proper "pinch" isn't going to reduce gas velocity. The small pinch and fast recovery used by Kooks provides a conserverative benefit from the merge collector.

0MarylandSpeed

I believe the idea is that Kooks feels an agressive merge is too much for a street car. Think of it like this...if you very slightly pinch a hose..you increase water velocity enough that you are moving more water, even though it is through a slightly smaller daimeter hose.. You pinch the hose too much however and you can loose efficiancy quick..where the reduced diameter "pinch" is allowing less air through than is gained by the increased velocity. I guess what I am saying is a merge collector is like pinching a garden hose...you have to do it just right to get best flow.

I am not really trying to get into a pissing match over merge collectors..there are plenty of great products out there..and odds are you won't go wrong with any choice.