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- - OBX Headers? (http://zr1.net/forum/showthread.php?t=13458)

Re: OBX Headers?

Quote:

Originally Posted by sammy (Post 143977)

dominic , what i did was i dynod the car with the stainless works/ obx style then went and took off the headers of the 90 which has a blown head gasket ugh . and put them on the 92 and re dynod the car 2 day later on the same dyno and the car made 17 more rwhp and 6ft pound of tq more than with the stainless works set up . the only thing that was changed was the headers . what i found was the stainless works /obx headers primary pipes ranged from 10in to 24 in and the collector really pinched off where the primary pipes ended into the collector . in fact when i took the car to coreys a couple of years ago after putting headers on . the first pull on the car only netted a 3 wrhp difference 372 was stk and 375 was the first pull . corey did his magic and got it to 389rwhp now granted it was 2 different dynos. but it no where came close to the improvement i got from my 90 when i installed the jeal headers. that car went from 331 stk to 368 with just the header change . those tests where done on the same dyno but 1 month apart. the jeal headers primary pipe lengths were short 22in -24 in and the collector was a true collector not this pinched off thing. . also when i started taking the 92 to the strip the car trapped 112.6-113.2mph stk and after the install and coreys tune only went to 114.9-115.6 . i found extra power when i changed out the corsa which was on it stk to a 3in xpipe then went with the stk 23/4in pipe to 3 in super turbo mufflers with dual exits to keep a stk look . it now traps 117.5 118.6 depending on the da that day(that was still with the stainless headers ) . i have g teched the car with the jeals and it is up almost 2 miles ann hr over the gtech runs with the old setup . i hope to try to find some time this next month to validate my g tech numbers with real drag strip numbers . . to give a hint my 90 which only has coreys porting tune jeal headers and dr gas 21/2 exhaust trapped a high of 119.47 miles an hr . the da that day was almost 3000 ft . the 92 has the callaway porting in the inj housings and plenum and also has porting done on the heads .. pete was telling me that the callaway porting was not very good .soon as i get strip numbers i will post the videos and slips for everyone to ck out and decide for themselves which way they want to go .

Did you get a compression test right before the dyno pull before the head gaskett blew. I wondering if it was failing during that pull?

Dave

Re: OBX Headers?

the head gasket failure was on my 90. the comparison tests were done on my 92 which is running fine . decided to switch headers as it will be a while before i can get to fixing the 90. work this time of year is a 16 hr a day deal .

Re: OBX Headers?

Quote:

Originally Posted by ZZZZZR1 (Post 143979)

First off, let me say I'm sure Corey's headers are far superior than OBX (not just the fact that they are produced in China).

Quality product from a QUALITY ZR-1 tuner in the US!!!!! Bonus!

As far as saying OBX / Stainlessworks headers are going to give you far less "RWHP" or MPH (in the quarter mile) is doubtful.

Brad is comparing two different cars and not the "same" car. In order to get a true comparison, you must install OBX/Stainlessworks and dyno the car. Then uninstall and reinstall Corey's headers and do the same test.

I have StainlessWorks headers (relatively happy with it), but if Corey was making his a few years ago.... I would have purchased his!

Love to see a "true" test of all of the headers....

:cheers:

David

i am sorry maybe i didnt write it correctly . the comparison was done on the same car . i took the headers off the 90 as the head gasket was blown on that car and put the jeal headers on the 92 . the power difference was to the 92 car . it made 17 wrhp more and 6lbs of tq more with the jeal than with the stainless works /obx design . all dyno runs were done on the same dyno on different days.also it was just a little warmer on the tests with the jeal headers . we did 4 pulls on both tests . all pull were within 4wrhp of each other .the only change to the car was changing the headers , i used the same exhaust that was on the car and didnt do anything in the way of tuning the car . it allways buged me that my 90 made more power with just with just headers and inj housing and plenum porting than my 92 which is a callaway 475 super natural . this motor has ported inj housing plenum and heads ,as a part of the callaway 475 pkg . next i want to put coreys ported inj housings and plenum thats on the 90 on the 92 and see what the difference is .

Re: OBX Headers?

Excellent thread Sammy. I emailed Corey to quote me a set of his headers. I'm ready for a set and based on your findings this will be the direction I will go. I will remind him to send you a commission check ;)

Re: OBX Headers?

All:

Been a long time since I was involved with headers, but I did have something to do with Stainless Works design. And I can tell you that Billy Kirchoffer (sp) originally started the process by having SW's pattern a Jeal header (which was a copy of the original Watson design, only utilizing one piece primary pipes). He stopped communicating with SWs and I picked up the ball and ran with it about a year later. Someone mentioned Corey's headers being longer than SWs. That's rather confusing to me.

If that is true, Either Corey has changed the design of the original Jeal's, or SW's has changed the design of it's version. As mentioned, the original SWs design, with the exception of the 1/4" flange (which was changed to 3/8" after about 10 sets were completed), looked exactly the same, and performance was the same. I have them on my car and it makes@400rwhp with Corey's port work. Which begs the question: How on earth does Jeal's design make even a couple more horsepower? I could see the difference maybe varying 2rwhp due to natural variables, but 12? That's rather hard for me to believe.

Is it possible that some people are confusing the OBX 'short tube' design as being similar to SW's? Again, maybe SW's redesigned their header to be a 'short tube' design, but I rather doubt it. Finally, I'm all for Corey getting the business, he's a great guy with a lot of talent and a true ZR-1 lover. SW's, while also a great company, produce products for *all* cars. I'm simply trying to make sure everyone (myself included) has accurate information re: various header designs.

Brian A.
90 ZR-1
ZR WON
12.09@118
01 Z06
not quite stock

Re: OBX Headers?

I don't know about the HP thing.
I will add i have installed all headers Watsons,SW and Jeals.

From the 3, Jeals install best/easiest.

Pete

Re: OBX Headers?

Pete:

How's it going? Been a long time. I am not refuting your installation experience; at this point you've done many more than me. I'm simply trying to make sure everyone has accurate information. What's confusing to me is Sammy typed that his SWs looks just like OBXs design. That leads me to two possible scenarios: 1) SW's changed it's design and are now selling 'short tube' headers or 2) Sammy is mistaken.

I have a set of Watsons and SWs somewhere (in the attic I think ;) ), and also have photos somewhere (which I can't readily find ;) ). What I can tell you from memory is the Watsons and SWs look *exactly* the same, sans the former having the primary tubes pieced together and welded. And Watsons are a true long-tube design (as are Corey's/Jeals). There is simply no way that a Watson/Jeal/SW design header is going to have a 12rwhp discrepancy between them. Now, a short tube design like OBX? I can totally believe it.

Brian A.
90 ZR-1
ZR WON
12.09@118
01 Z06
not quite stock

Re: OBX Headers?

Anybody got a pic of the Jeal/Corey headers. How long does a long tube header have to be to be a long tube header? -Steve

Re: OBX Headers?

Here are the photos I have for the various headers (Jeal, SWs, Watson, and OBX, respectively). As you can see, the Jeal/Watson/SWs likely have an additional 2-3" worth of pipe in comparison to the OBX design (the Watson photo is of the 1-3/4" primary version, which is quite rare). As mentioned previously, I could see how the shorter tube OBX design wouldn't produce the power numbers of the Jeal/SWs/Watsons.

Also, I ran out to the garage and measured the primary length on my SWs on the drivers side (couldn't get to the passengers) They are:

#1: 25"
#3: 21.5"
#5: 19"
#7: 16.5"

Unless Corey has patterned his 'new' headers after the one of two truly equal length primary header sets ever manufactured (by LPE), his are going to measure roughly the same. I don't own OBX, so I cannot comment with actual measurements, but based on the photographic evidence, they are visibly shorter.

Brian A.
90 ZR-1
12.09@118
ZR WON
01 Z06
not quite stock

Re: OBX Headers?

If any one has a set of headers they're lOoking to get rid of at a cheap price lemme know