Thirdgen Header option chart - explained
Joined: Jun 2002
Posts: 13,576
Likes: 30
From: Harford County, MD
Car: camaro sportcoupe
Engine: 7.0L
Transmission: G-Force GF5R
Axle/Gears: Moser 9"
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.
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.
Last edited by mw66nova; Jan 25, 2004 at 01:52 PM.
Supreme Member
Joined: Jan 2003
Posts: 1,059
Likes: 0
From: Woodbury, NJ
Car: 87' Iroc
Engine: 350
Transmission: 700R4
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.
Junior Member
Joined: Jan 2004
Posts: 2
Likes: 0
addition to heade option chart
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.
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.
Banned
Joined: Sep 2003
Posts: 645
Likes: 0
From: illinois, home of liberals, D'oh!
Car: 89 Formula L98 power
Engine: '96 subaru, opposed 4banger
Transmission: TH700R4, subaru 4WD
Axle/Gears: 3.27, just works
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
Check out my site for other mod info.
http://www.cardomain.com/id/cronsformula
Thread Starter
Joined: Jul 1999
Posts: 12,089
Likes: 125
From: SALEM, NH
Car: '88 Formula
Engine: LC9
Transmission: 4L60E
Axle/Gears: 3.89 9"
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.
Check out my site for other mod info.
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.
Banned
Joined: Sep 2003
Posts: 645
Likes: 0
From: illinois, home of liberals, D'oh!
Car: 89 Formula L98 power
Engine: '96 subaru, opposed 4banger
Transmission: TH700R4, subaru 4WD
Axle/Gears: 3.27, just works
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.
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.
Last edited by cronsformula350; Feb 17, 2004 at 01:50 PM.
Thread Starter
Joined: Jul 1999
Posts: 12,089
Likes: 125
From: SALEM, NH
Car: '88 Formula
Engine: LC9
Transmission: 4L60E
Axle/Gears: 3.89 9"
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.
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.
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
Supreme Member
Joined: Aug 2001
Posts: 1,108
Likes: 1
From: Western NY
Car: 2007 Saturn Sky Redline
Engine: 2.0 turbo
Transmission: m5
Axle/Gears: 3.91 LSD
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?
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?
Thread Starter
Joined: Jul 1999
Posts: 12,089
Likes: 125
From: SALEM, NH
Car: '88 Formula
Engine: LC9
Transmission: 4L60E
Axle/Gears: 3.89 9"
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
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
Banned
Joined: Sep 2003
Posts: 645
Likes: 0
From: illinois, home of liberals, D'oh!
Car: 89 Formula L98 power
Engine: '96 subaru, opposed 4banger
Transmission: TH700R4, subaru 4WD
Axle/Gears: 3.27, just works
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!
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!
Thread Starter
Joined: Jul 1999
Posts: 12,089
Likes: 125
From: SALEM, NH
Car: '88 Formula
Engine: LC9
Transmission: 4L60E
Axle/Gears: 3.89 9"
just come out to my drag strip, and I'll run you, and put your newbie lingo to the test.
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.
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.
-- Joe
Thread Starter
Joined: Jul 1999
Posts: 12,089
Likes: 125
From: SALEM, NH
Car: '88 Formula
Engine: LC9
Transmission: 4L60E
Axle/Gears: 3.89 9"
I switched to SLP 1 3/4.. WIth my setup (approaching 550-600hp) I really think I needed the larger primaries..
Will report results soon.
-- Joe
Will report results soon.
-- Joe
Thread
Thread Starter
Forum
Replies
Last Post
eightsixseven
Tech / General Engine
2
Dec 16, 2024 01:50 PM
