So I've been pondering my torque numbers and comparing it to some on the Grand Sport Registry Dyno page. If you've followed any of my thread you know the story. Most with similar mods but with headers/exhaust are making more torque than me so the only thing I can think is my problem is flow going out. Does this seem logical?

I'll probably have the money soon for far just about any header I want. I like the EM longtubes for the proven results. However I see there there is a standard so to speak 1 3/4" header and a "High Horsepower" 1 7/8" set. Which do you think? Are the 1 7/8" set too big?

I think headers and some free flowing cats will really wake up this package more than it already is.

 

Although not your question, I think the 1 3/4 ones are too big, especially since your goal is better torque numbers. Are the 1 7/8 headers stepped or just 1 7/8 all the way? If they're not at least stepped, you really don't want them.

 

Well what is everyone buying in the EM longtubes? The only ones I see on their website are those two with not much more information.

My thinking is; since I believe I have better flow going in now it's just not going out at the torque peak or what should be the torque peak.

There must be more flow, I don't see any LT4 cars with just a Hot Cam making 344 RWHP. They are with the Hot Cam and headers but make 334 peak torque compared to my 316 or so.

I need some kind of headers and exhaust, I looked into Kooks but I don't see anything listed for a C4. Apparently C5's and C6's are the only cars worth anything anymore.

Is there a better alternative to the EMs, I'm not concerned about price within reason, more in quality. I've had cheap headers before and don't want to go there again.

I'm tired of being TOO conservative, I usually conservative myself right out of power. This is why I was considering the 1 7/8" headers, if they're too big I'll do some more work on the heads or swap them, install a larger cam and make them work.

Plus a 383 build isn't out of the question for next summer.

 

If they are just straight 1 7/8" headers, they are way too large for anything short of a blown stroker. FD2BLK has a 383 making well in excess of 400 RWHP and RWT and is using the 1 5/8" Stainless Works headers on his. I'm also using them on my 388 which hasn't been dynoed yet, but I expect nice numbers. Definitely don't go larger than 1 3/4" unless they are stepped headers. Personally, I'd still recommend the 1 5/8" header for you, even with your possible future mods, but it's not my goal to dredge up that old argument in your thread, so that's all I'll say about it. I wish someone would make a stepped 1 5/8 to 1 3/4" header for these cars. I'd be on them like a fly on a steaming turd!

 

An 1/8 inch in diameter aint gonna kill the torque. If you're planning upgrades in the future, especially in cubes, go with the bigger header.
I will tell you this, though, a good tune should pick up the torque # pretty close to where you think you should be. Im only seein about 16 lbs ft, right? I can tell you from exp that headers, good flowing cats (which actually make the biggest diff by themselves) AND a tune and you're looking at a SIGNIFIGANT improvement in both #. 35 hp or better at the wheels. I've seen 50 on LS1 cars

 

No one said anything about killing the torque. I'm only speaking of maximizing it in the ranges where it's most utilized. Damn you big header guys are touchy! Okay, I'm really gonna shut up now.....

 

Byan Herter of PCmforless personally tuned my car this past Wednesday that's where my torque number came from. The first thing he said was "you need headers" so a tune isn't going to help.

Corvette Kid, I'm not concerned about track numbers right now, they'll fall into place. This is more about getting the right headers to compliment the motor. BUT, I don't want to go too small and be right back where I started from.

BTW, new CATS will be going on also. That's a whole different thread when the time comes. The Headers will be purchased as soon as I figure out WTF to get.

 

With everything... then again I may be a bit biased... I just got my Stainless Works headers in -- can't wait to install them (mid-late Sept. I imagine). But don't they look purdy ?



[click thumbnail for larger image]

 

Purdy headers make my sticker peck out!

 

Dont mean to sound touchy. Didnt mean it that way at all. This is the deal with header size from my seat. If you're trying to create or maximize LOW END torque (motorhomes, towtrucks) then small tubes are better. If you're trying to increase the torque at its peak, MOST of the time bigger is better. Of course this doesnt mean a 2 1/4 header on a 350. We put a set of headers on a 302 mustang (oh, Im gonna get it now!) that I thought were too big, ALONG with some MONSTER 3 1/2 exhaust ,cut off after the flowmasters, NO OTHER MODS, except cold air intake that was already there. I just knew we were gonna kill it. IT PICKED UP .6 IN THE 1/8 I couldnt believe it! We've had other experience with sbc drag cars with headers that were too small. Not saying 1 5/8 or 1 3/4 are too small for this car, just that 1 7/8 arent too big, especially for a 383 with a healthy cam.
PS If Bryan couldnt get anymore out of it I retract my statement about a good tune, Bryan IS the man!!

 

The EM's are tuned, the Stainless Works don't appear to be tuned, the lengths are different. Or am I wrong here?

Which would you rather have on your car?

EM Long Tubes...


Stainless Works...

 

Strangely every pic of SWs headers that I have seen have been different in some way... mostly in the collector and flanges... at any rate -- I thought another key point in exhaust systems was to not have the exhaust gases travel backwards at any point... isn't that what the EMs do? -- not that I am trying to bash the EMs in any way -- I am sure they are an excellent header - I almost got those, but really wanted stainless steel and 1 5/8" primaries (I think EM may carry such a thing, but SWs reputation and fitment brought my attention to them)...

 

Damn they're both sweet!! the polishing on the EMs just make em look better

 

Alot of "tuned headers" as well as race only headers do that . Not sure if it makes any differance. To build tuned headers you almost have to do that.

 

I could care less if they both were pink. Look at the lengths of the tubes, the EM's are of equal length, the SW's are not. I was always under the impression that this offered the best scavenging effect.

Stainless doesn't mean a hill of beans if they're not designed correctly. Frankly they look like the crap I had on my old rod with no symmetry to the tubes whatsoever.

I think I'm ordering the EM 1 3/4" just like the Hot Cam, they're a proven performer for the money.

 

Without pretending to know any facts about how well each one "scavenges" (though to my untrained eye I would think the SWs look better at getting exhaust gases out properly..)-- my MAIN reason for going with SWs is because I never plan on taking these headers off to get them recoated like so many others have to do with coated non-stainless headers... rusting and such would be a nightmare for me to deal with... At any rate -- I'll only really know what I think of my SWs when I get them installed -- and I'm sure I'll post a sound clip...

 

I agree about the equal length being better. Thats why I posted about the ex. going "backwards" not seeming to be an issue. almost evry tuned set Ive seen they had to make that way.

 

If you check the lengths of most any street header, you'll find a few inches of variation on any of them, some more than others of course. The only reason for equal length is for optimizing performance in a given RPM range. For instance, an oval track car that runs on a short track with tight corners would use longer tubes of a smaller diameter for torque off of the corner and down the straight. The same car on a track where there was less RPM drop (faster corners and/or a bigger track) would use a header with shorter tubes and a larger diameter because the engine stays much closer to maximum RPMs at all times. Also a given drag application that launches at a high RPM and stays there would want a larger size for their engine package whereas if they leave from a lower RPM, they'd want the smaller stuff once again. This is where equal length and ideal header tuning really come into play. On a street car, the goal of headers is to simply get the individual cylinder pulses a longer way from the engine before they blend to greatly improve scavenging and thus aiding flow. Much like the X or H pipe do for the individual sides of the system further back.
There's nothing wrong with either primary size on these cars for most of us, it's not gonna make or break the end result. But, good headers are a sizeable investment for these cars so I like folks to be informed and then choose what they'd like. But I'm far from the end-all expert on exhaust theory and don't wish to convince anyone that I am. It's a science that goes way beyond my understanding. I just have to go by what I've read over the many years I've been a hotrodder and glean what I believe is right from the many true experts whose ideas I've studied. Of all of the great headers made for these cars, there are no bad choices. SW, EM, TPIS, Melrose, (have I forgotten any still in production?) are all good stuff. I would definitely not put a 1 7/8" header on any 'real-world' small block street engine though. I'm talking about any engine that would actually be tame enough for real streetability and daily use. That would a torque killer in the RPM ranges where your engine will operate 99.9% of the time.

 

I don't think you will get a real tuned header that has equal tube length based on the fact of the car, clearances etc. Race cars can because of no fender wells and accessories to clear, therefor they can build w/equal tube length and also have a less radical bend from the head. I agree w/Chris but 1 3/4" would be fine. The 1 5/8 would maximize torque but part of that will also have to do with what you choose for the rest of the system.

 

BTW, the only truly equal length headers I've seen for a C4 are the old LPEs, no longer made. They are some ganglely looking *****! They look cool but I wouldn't care for them on a street car. A friend of mine has them on an '85 racer and got totally aggravated trying to bolt them on. A young, patient Asian friend of his stopped by and finished it for him.