Thirdgen Header option chart - explained - Page 2 - Exhaust - Third Generation F-Body Message Boards

mw66nova · 01-25-2004, 01:50 PM

i don't know man, it probably would help. what i am saying is that my friend has a 3400lbs. fourthgen running 10's on 1 5/8" shorties. you could probably do the same on say a set of MAC or hooker 2055's. MAC's are cheaper though (if you get in on the group on this page)

the thing you have to remember is that the slp's y-pipe bottlenecks down to 2 1/4". that is where you are going to be hurt performance wise. a set of MAC's or Hookers comes with a 2 1/2" y-pipe that y's into a 3" pipe.

StealthElephant · 01-25-2004, 02:08 PM

So it's basically a choice of where you want your restriction, the exhaust gas spends not much time in the primaries....so it isn't a huge issue if the collector and everything else flows well.

marclewis · 01-27-2004, 05:50 PM

Hedman Hedders also manufactures an ELITE version of the 68470 listing shown. HEDMAN part number 68478 has 14 gauge 1-5/8" primaries and .375" flanges all around. THis header already comes with a ceramic metallic coating, so it needs no additional coating.

the same Y-Pipe works for either the standard 68470, or the 68478 Elite model. Hedman's Y-Pipe number 17470 is made specifically to use with these Hedman Hedders

Oh, if you don't mind spending a bit more for more horses, there is also a stepped tube version called tork-step that has tubes that are stepped. Stepped tube headers have been used for racing applications, like NASCAR, for years. the tubes step from 1-1/2" to 1-5/8". The step in the tube speeds up exhaust flow, and the more exhuast gas you can get out of the combustion chamber, the more fresh fuel your intake can feed it. More fresh fuel translates into more torque. They really do work. the part number for the stepped header is 68474.

cronsformula350 · 02-17-2004, 12:18 AM

sorry to get off topic, but Iroc57L, the stock 22 lb/hr injectors will accomodate up to 450hp+ and do it very well with increased pressure, because they have a great spray pattern. Unless your pushing 425 hp, running anything larger than a 22 lb/hr injector will reduce the efficiency of the injectors, and they will act lazy. You would have to run a higher pressure along with the larger injectors to achieve a similar spray pattern, which would probaby make your car run on the rich side, and hurt your over all power out put. If you really need new injectors, just buy a new set of 22lb/hr's and a pressure regulator. I ran 14.70's in my 89 formula 350 while slipping, and I only had a flowmaster muffler.

Check out my site for other mod info.

http://www.cardomain.com/id/cronsformula

anesthes · 02-17-2004, 06:50 AM

Quote:

sorry to get off topic, but Iroc57L, the stock 22 lb/hr injectors will accomodate up to 450hp+ and do it very well with increased pressure, because they have a great spray pattern. Unless your pushing 425 hp, running anything larger than a 22 lb/hr injector will reduce the efficiency of the injectors, and they will act lazy. You would have to run a higher pressure along with the larger injectors to achieve a similar spray pattern, which would probaby make your car run on the rich side, and hurt your over all power out put. If you really need new injectors, just buy a new set of 22lb/hr's and a pressure regulator. I ran 14.70's in my 89 formula 350 while slipping, and I only had a flowmaster muffler.

Check out my site for other mod info.

At 65 psi and STATIC a 22# injector, assuming a BSFC of .50 is can barely support 429HP. And these are unrealistic numbers.

The highest rail pressure you'd want to run would be around 55psi, 60 max.. BSFC will hardly ever be .50, but even if it was and about an 85% duty cycle would be around 335hp.

Please do not post again until you have half an idea what your talking about.

cronsformula350 · 02-17-2004, 01:45 PM

oh, well its funny that you say that, because tpis has used stock injectors on 350's putting out over 450 hp, with increased fuel pressure.

This is right out of the TPIS insider hints book.

With the tpi system it is not uncommon to generate bsfc #'s on the order of .40 to .45. After four years of testing tpi engines, with displacements ranging from 305-406 ci, we have found that the stock 350 injector is capable of flowing enough fuel for over 450 hp, and a 305 injector should flow enough fuel for 350+ hp. We have successfully used stock 350 nozzles on supercharged 350's and n/a 406 engines. Raise the fuel pressure with a adjustable fuel pressure regulator, and you have even higher fuel flow capabilities. Perhaps you should do some more research. Not to mention my local shop has used 22 lb/hr injectors and has built motors that produce over 450 hp with cleaned stock 22/lb hr injectors, and my shop builds motors that produce over 2700 hp.

http://www.borowskirace.com/

Sorry to get off topic, but I'm going to back up what I said.

anesthes · 02-17-2004, 02:11 PM

Quote:

oh, well its funny that you say that, because tpis has used stock injectors on 350's putting out over 450 hp, with increased fuel pressure.

This is right out of the TPIS insider hints book.

With the tpi system it is not uncommon to generate bsfc #'s on the order of .40 to .45. After four years of testing tpi engines, with displacements ranging from 305-406 ci, we have found that the stock 350 injector is capable of flowing enough fuel for over 450 hp, and a 305 injector should flow enough fuel for 350+ hp. We have successfully used stock 350 nozzles on supercharged 350's and n/a 406 engines. Raise the fuel pressure with a adjustable fuel pressure regulator, and you have even higher fuel flow capabilities. Perhaps you should do some more research. Not to mention my local shop has used 22 lb/hr injectors and has built motors that produce over 450 hp with cleaned stock 22/lb hr injectors, and my shop builds motors that produce over 2700 hp.

http://www.borowskirace.com/

Sorry to get off topic, but I'm going to back up what I said.

The TPIS book is filled with errors and mistakes. TPIS is not very popular on this site as far as advice and methods go. A lot of us have been doing this a long time, and have learned from mistakes of poor advice.

Stock lucas injectors have been proven on ECM benches to go erratic at high pressures and high duty cycles.

I don't need to do any more research. Your the newbie.

-- Joe

Speedgraphic · 02-17-2004, 02:30 PM

Gentlemen,

Please observe the "Marquess of Queensbury Rules" at all times...

Inwo · 02-17-2004, 03:45 PM

anesthes: 22lb/hr injectors might be a little much for your meager combination, might want to step down to a set of 18s and run at 80psi base fuel pressure with an inline Aeromotive pump to push it over 150psi under boost.

Then again you might just do like you already did and run bigger injectors instead of trying to sell a "clean and balance" service for near the cost of a new set of injectors. Compensation of smaller injectors with higher fuel pressure works, yes, but if you can run bigger injectors with the same or better driveability while at the same time not running your fuel pump at higher pressure constantly reducing its lifespan and using fuel pressure to compensate for too-small injectors then why wouldn't you?

anesthes · 02-17-2004, 05:18 PM

Inwo,

18s sound great. With a WOT pressure of 150psi, the spray pattern and velocity will be so high that I should get great atomization..

And I thought my 24# were maxed out at 65psi and 93% duty cycle. Shoulda just put 3 more pumps inline, and set the pw static.

-- Joe

cronsformula350 · 02-17-2004, 10:36 PM

anesth' your right I'm just a newbie and I don't know anything, just come out to my drag strip, and I'll run you, and put your newbie lingo to the test.

This is my last post here, b/c of rules. I don't talk stuff, rather give some good advice when I think it is helpful to someone else, rather than go off on me, just come out to the track in your car, and like I said, and I'll destroy you in my formula; and If I get really ambitous I'll take out our 68 GTO with our 461, and just over 650 hp at the flywheel.

newbie thats funny, I don't have to post about anything important
because I know what needs to be done, I've been surfing these forums for several years now, and have been in to cars for more than half of my lifetime already, I'm no stroke or newbie!

25THRSS · 02-17-2004, 11:36 PM

wow, thought this was a good post about headers until ummm

anesthes · 02-18-2004, 06:27 AM

Quote:

just come out to my drag strip, and I'll run you, and put your newbie lingo to the test.

"My car is faster than yours, blah blah". Your a kid in school, noone wants to hear it. You want to be respected around here, change your attitude. I'm not impressed with you, or your cars. My car goes 12s, maybe 11s this spring and that still doesn't impress me. About the only thirdgen on here that DOES impress me is Tory Hess's 9 second street firebird. Otherwise, they're all just Thirdgens like mine.

Frankly I don't care if you run a 17, or a 10. If you give bad advice i'm gonna tell you. I don't care who's book you read. There are hundreds of guys on here (myself included!) who have proven TPIS wrong with numerous setups.

Quote:

just come out to the track in your car, and like I said, and I'll destroy you in my formula; and If I get really ambitous I'll take out our 68 GTO with our 461, and just over 650 hp at the flywheel.

Noone cares much for this attitude. The "Meet me at the track" crap sounds much like "meet me after school, and bring your lunch money too!".

-- Joe

GoSlash27 · 04-08-2004, 05:48 AM

One thing I notice conspicuously absent: Average primary length.
I s'pose that's a bit much to ask unless we get people to measure this prior to installation *shrug*

anesthes · 04-08-2004, 09:02 AM

Quote:

One thing I notice conspicuously absent: Average primary length.
I s'pose that's a bit much to ask unless we get people to measure this prior to installation *shrug*

If we're talking about shorties, they're all gonna be different. Even the hooker 2055's are not equal length. I spoke to them about this.

-- Joe

25THRSS · 04-08-2004, 11:49 AM

I am currently unaware of any equal length shorties made for third gens.

GoSlash27 · 04-08-2004, 01:49 PM

Yeah...that's why I said "average" primary length.
I'm not personally aware of anyone that makes a true equal length full length header either, but the average primary length still determines the scavenging RPM of the header.

vernw · 04-08-2004, 02:37 PM

I put a brand new set of the discontinued stainless SLP Tri-Y's in my 91 Formula when we pulled the 305 and put in the 383 a week ago. I had the dual cat set-up on this car, and I have to say that it's a shame SLP doesn't make these anymore. No denting was required, and the Y-pipes go right to the connections for the cats - no problem. No fitment problems at all. And that's while retaining the air conditioning, AIR pump, power steering, etc. We removed nothing to put these on the car. Very nice set-up. Only problem encountered was the SLP A.I.R. fittings both point up (vertical) while the original fitting on the driver's side was horizontal. Simple rubber hose bend fixed that one though. If you can find any of these, I recommend them highly!!! Plus ACS for the excellent coating job I had done on mine. Another great bunch of folks.

. - Vern

DocSausage · 04-20-2004, 06:56 AM

Anybody got the part numbers for ceramic coated, shorty, with air-tubes headers???

Speedgraphic · 04-20-2004, 09:15 AM

I installed ceramic coated Hedman shorties - I believe the number was 68481. They had the AIR tubes as well as the bung for the O2 sensor. They weren't Too hard to install - I guess...

cronsformula350 · 04-23-2004, 05:34 PM

I put some edelbrock tes shorties and y with the chrome coating on the shorties, and the installation went well plug access is good on all but the number 6,8 cylinders, all the rest were great, I can't wait to put a set on my daily driven 87, last night I chirpped third, and thats without headers, and a stock transmission, with just my trans cooler, ah mid 13's here we come.

My Site:
http://www.cardomain.com/id/cronsformula

IceManRS305 · 06-05-2004, 04:50 PM

im doin a 350 swap (carbed, no ecm)... is there any long tube headers that will fit? does it make a difference that i have a carbed 350? or is the room for headders still the same restriction wise?

Avenger007 · 09-28-2004, 08:13 PM

Sheesh...just when i thought the 2055s would suit me best...in comes the hedman long tubes and yadda yadda. So does a 2055 and its y-pipe bolt right up to a 3" cat and 3" flowmaster? or do i need to modify it. Also I was looking around for a good (cost effective) 1 3/4 header with a y-pipe that requires little modification. What is my best bet? the 68470? Can I get my hands on the Elites and y-pipe for around $500?

anesthes · 09-28-2004, 08:48 PM

Quote:

Originally posted by Avenger007
Sheesh...just when i thought the 2055s would suit me best...in comes the hedman long tubes and yadda yadda. So does a 2055 and its y-pipe bolt right up to a 3" cat and 3" flowmaster? or do i need to modify it. Also I was looking around for a good (cost effective) 1 3/4 header with a y-pipe that requires little modification. What is my best bet? the 68470? Can I get my hands on the Elites and y-pipe for around $500?

I'm not a 2055 fan but.. Yeah its bolt in.

68470 is 1 5/8"

-- Joe

Avenger007 · 09-28-2004, 10:14 PM

ya my opinion of the 2055s has changed throughout these posts. Im looking for a 1 3/4 now tho and It seems like the only ones making them is SLP and Hooker. Both exit to a 3". The hooker ones are 2210 Long Tubes. Anyone have experience with these. I found a topic about their installation but found nothing as to how effective they are performance wise, if they include y-pipe, and how much they cost. If 2210s work (ground clearance in mind after 1' drop) then itll go to y-pipe to 3" cat and then to a American Thunder 3" 80 series system. Sound decent if im looking for power and with 400+ hp in mind in near future?
thanks

anesthes · 09-29-2004, 06:20 AM

Quote:

Originally posted by Avenger007
ya my opinion of the 2055s has changed throughout these posts. Im looking for a 1 3/4 now tho and It seems like the only ones making them is SLP and Hooker. Both exit to a 3". The hooker ones are 2210 Long Tubes. Anyone have experience with these. I found a topic about their installation but found nothing as to how effective they are performance wise, if they include y-pipe, and how much they cost. If 2210s work (ground clearance in mind after 1' drop) then itll go to y-pipe to 3" cat and then to a American Thunder 3" 80 series system. Sound decent if im looking for power and with 400+ hp in mind in near future?
thanks

I'm running the hedmans.. My setups over 500hp.
IMO the long tubes are overkill.

-- Joe