Which header?
#26
05-20-2009
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Is it possible a body lift will allow it to clear the firewall? If there's a 50/50 chance I will probably try and see what happens. I can always sell them if it doesn;t work.
With the bosy lift, and the fact that I removed my spare tire carrier, I think i can fit the exhaust up high. In the bed area I can darn near put it above the frame.
With the bosy lift, and the fact that I removed my spare tire carrier, I think i can fit the exhaust up high. In the bed area I can darn near put it above the frame.
#27
05-20-2009
#28
05-20-2009
anyone know when factories went back to quoting flywheel hp instead of rear wheel hp? thought in 1972 factories started quoting rear wheel hp...1 of the reasons hp ratings from 1971 were way down?
#29
05-20-2009
Who knows what they did in the 70's. They had clout as well as a backbone back then. lol. They put whatever numbers worked for them to sell vehicles. They underrated for insurance purposes is what I remember.
Today's world is a standard measurement that is real. I say that cause they got caught a couple of times which is pretty interesting. One of the reasons there wasn't a 2000 Cobra was the 1999 fell short of advertised HP. They cancelled production as they swapped out manifolds in all the ones they had sold. To keep the Cobra name going, they produced a limited number of cobra R's so there would still be one for that year.
Thats my understanding anyways. I think the same thing happened with the RX8. Not sure. The neat thing is it takes someone removing from the car- separate from the tranny- to get the flywheel HP. You can usually slide if your off a little cause few people are gonne tear apart their car to prove something.
#30
05-20-2009
SAE explained...
SAE horsepower
SAE gross horsepower
Prior to the 1972 model year, American automakers rated and advertised their engines in brake horsepower (bhp), frequently referred to as SAE gross horsepower, because it was measured in accord with the protocols defined in SAE standards J245 and J1995. As with other brake horsepower test protocols, SAE gross hp was measured using a stock test engine, generally running with few belt-driven accessories and sometimes fitted with long tube (test headers) in lieu of the OEM exhaust manifolds. The atmospheric correction standards for barometric pressure, humidity and temperature for testing were relatively idealistic.
SAE net horsepower
In the United States the term "bhp" fell into disuse in 1971-72, as automakers began to quote power in terms of SAE net horsepower in accord with SAE standard J1349. Like SAE gross and other brake horsepower protocols, SAE Net hp is measured at the engine's crankshaft, and so does not account for transmission losses. However, the SAE net hp testing protocol calls for standard production-type belt-driven accessories, air cleaner, emission controls, exhaust system, and other power-consuming accessories. This produces ratings in closer alignment with the power produced by the engine as it is actually configured and sold. The change to net hp effectively deflated power ratings to assuage the auto insurance industry and environmental and safety lobbies.
SAE certified horsepower
In 2005, the SAE introduced a new test protocol for engine horsepower and torque.[12] The new protocol eliminates some of the flexibility in power measurement, and requires an independent observer present when engines are measured. The test is voluntary, but engines completing it can be advertised as "SAE-certified".
Many manufacturers began switching to the new rating immediately, with multi-directional results; the rated output of Cadillac's supercharged Northstar V8 jumped from 440 horsepower (330 kW) to 469 horsepower (350 kW) under the new tests, while the rating for Toyota's Camry 3.0 L 1MZ-FE V6 fell from 210 horsepower (160 kW) to 190 horsepower (140 kW). The first engine certified under the new program was the 7.0 L LS7 used in the 2006 Chevrolet Corvette Z06. Certified power rose slightly from 500 horsepower (370 kW) to 505 horsepower (377 kW).
SAE gross horsepower
Prior to the 1972 model year, American automakers rated and advertised their engines in brake horsepower (bhp), frequently referred to as SAE gross horsepower, because it was measured in accord with the protocols defined in SAE standards J245 and J1995. As with other brake horsepower test protocols, SAE gross hp was measured using a stock test engine, generally running with few belt-driven accessories and sometimes fitted with long tube (test headers) in lieu of the OEM exhaust manifolds. The atmospheric correction standards for barometric pressure, humidity and temperature for testing were relatively idealistic.
SAE net horsepower
In the United States the term "bhp" fell into disuse in 1971-72, as automakers began to quote power in terms of SAE net horsepower in accord with SAE standard J1349. Like SAE gross and other brake horsepower protocols, SAE Net hp is measured at the engine's crankshaft, and so does not account for transmission losses. However, the SAE net hp testing protocol calls for standard production-type belt-driven accessories, air cleaner, emission controls, exhaust system, and other power-consuming accessories. This produces ratings in closer alignment with the power produced by the engine as it is actually configured and sold. The change to net hp effectively deflated power ratings to assuage the auto insurance industry and environmental and safety lobbies.
SAE certified horsepower
In 2005, the SAE introduced a new test protocol for engine horsepower and torque.[12] The new protocol eliminates some of the flexibility in power measurement, and requires an independent observer present when engines are measured. The test is voluntary, but engines completing it can be advertised as "SAE-certified".
Many manufacturers began switching to the new rating immediately, with multi-directional results; the rated output of Cadillac's supercharged Northstar V8 jumped from 440 horsepower (330 kW) to 469 horsepower (350 kW) under the new tests, while the rating for Toyota's Camry 3.0 L 1MZ-FE V6 fell from 210 horsepower (160 kW) to 190 horsepower (140 kW). The first engine certified under the new program was the 7.0 L LS7 used in the 2006 Chevrolet Corvette Z06. Certified power rose slightly from 500 horsepower (370 kW) to 505 horsepower (377 kW).
Brake horsepower
Brake horsepower (abbreviated bhp) is the measure of an engine's horsepower without the loss in power caused by the gearbox, generator, differential, water pump, and other auxiliary components such as alternator, power steering pump, muffled exhaust system, etc. "Brake" refers to a device which was used to load an engine and hold it at a desired RPM. During testing, the output torque and rotational speed were measured to determine the "brake horsepower". Horsepower was originally measured and calculated by use of the indicator (a James Watt invention of the late 18th century), and later by means of a De Prony brake connected to the engine's output shaft. More recently, an engine dynamometer is used instead of a De Prony brake. The output delivered to the driving wheels is less than that obtainable at the engine's crankshaft.
Brake horsepower (abbreviated bhp) is the measure of an engine's horsepower without the loss in power caused by the gearbox, generator, differential, water pump, and other auxiliary components such as alternator, power steering pump, muffled exhaust system, etc. "Brake" refers to a device which was used to load an engine and hold it at a desired RPM. During testing, the output torque and rotational speed were measured to determine the "brake horsepower". Horsepower was originally measured and calculated by use of the indicator (a James Watt invention of the late 18th century), and later by means of a De Prony brake connected to the engine's output shaft. More recently, an engine dynamometer is used instead of a De Prony brake. The output delivered to the driving wheels is less than that obtainable at the engine's crankshaft.
#31
05-20-2009
You have to be carefull. You don't want to expose a water jacket in your cylinder heads.
Here is something I read which I thought was interesting. The air leaves the exhaust port from the top. The air wants to "curl" down and head back into the engine. If you could take your stock exhaust manifold and move it up 1/4 to 3/8 of an inch it would create a wall on the bottom. The curled air would hit that wall and stop. So you didn't decrease the flow, the top of the cylinder port would have to be ported taller to match the new location of the exhaust manifold. never tried it, don;t know if is doable, don;t know if there are any gains. It sounded interesting though.
My personal belief is gains are limited unless you deal with the large number of cats in the system. Any increased flow is limited to the weakest link. I don;t believe the weakest link is the exhaust manifold.
#32
05-20-2009
In the 70's they "measured" flywheel horsepower with no accessories, no a/c, alternator, water pump, nothing. In '72 I think, They started rating flywheel HP with all accessories, thus the drastic drop. Now all testing is done in "as installed in car" configuration, at the flywheel. The drivetrain is still a variable in the real world.
So basically, the numbers now are realistically what the motor puts out. Chassis dynos will still show different numbers depending on transmission and gear ratio.
So basically, the numbers now are realistically what the motor puts out. Chassis dynos will still show different numbers depending on transmission and gear ratio.
#33
05-20-2009
Join Date: Apr 2009
Location: Owensboro, KY
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so which of the JBAs on summits site would you guys reccomend? theres like 3 or 4. heres the link if it works: JBA on summit
#34
05-20-2009
theres really only one model that will fit your engine. The only choice is whether you have an egr and if so, which side of the motor it is on.
After that you can get stainless which is least expensive
or ceramic coated in silver or titanium. The ceramic will hold in the heat better and look better. It comes with an added price though.
After that you can get stainless which is least expensive
or ceramic coated in silver or titanium. The ceramic will hold in the heat better and look better. It comes with an added price though.
#36
05-20-2009
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#37
05-20-2009
#38
05-20-2009
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#40
05-20-2009
#41
05-20-2009
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ok, ic. someone on here was sayin that long tubes bring the best numbers so thats what i was lookin for. so is there a performance difference between all the JBAs? i rele dont wanna spend 500 on a set of headers. i was thinkn 3-350. so if i dont wanna spend the money on the ceramic ones (its not like im racin or nething and nethings better than stock i guess) which ones would you reccomend. and thoughts on gibson/
#42
05-20-2009
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#43
05-20-2009
zach, the Gibson is gonna be mild steel with a chrome plate. The chrome will discolor after time. You will eventually get some rust on them.
Unless you are saving a lot of money i would stick with the stainless steel. Last I looked the price was relatively the same.
for the 4.0 guys, JBA dropped the price a few months ago on one model only for Explorers. By one model I mean the same egr configuration that the explorers have. Can't remember if it with the egr, without it, or which side it is on. If you can make that one work on your Ranger it will save about $100. The egr can be capped of easily, but it can't be added onto the headers.
Unless you are saving a lot of money i would stick with the stainless steel. Last I looked the price was relatively the same.
for the 4.0 guys, JBA dropped the price a few months ago on one model only for Explorers. By one model I mean the same egr configuration that the explorers have. Can't remember if it with the egr, without it, or which side it is on. If you can make that one work on your Ranger it will save about $100. The egr can be capped of easily, but it can't be added onto the headers.
#44
05-21-2009
Man guys have been doing this for well over 50yrs.
I've been doing this for over 20yrs.. have even done this to my Lightning.
The biggest restriction is not the iron manifolds. It's the cats.
Here is a pic from my Lightnings Fox lake ported heads and the manifolds.
Rich
#45
05-21-2009
This is most likely not a rule of thumb. W/O doing a thermal and computational fluid dynamic study.. there is no way to know what a particular combustion chamber, port, and exhaust manifold will do.
The "shade tree" way to maximize this is to make the exhaust manifold slightly bigger in crossection than the port.
Also, the crosectional area of the manifold should remain equal until it reaches the open plenum area.
In reality though guys.. I'm talking about very small details that pale in comparision to mid pipe/cat restrictions.
btw, on my Lighting (when it was stock) I switched the stock cats for a cat-less mid pipe. Manifolds were untouched.. my trap speeds went up by nearly 2.5mph.
Bang for the buck.. it's the cats that need attention.
#46
05-21-2009
This is most likely not a rule of thumb. W/O doing a thermal and computational fluid dynamic study.. there is no way to know what a particular combustion chamber, port, and exhaust manifold will do.
The "shade tree" way to maximize this is to make the exhaust manifold slightly bigger in crossection than the port.
Also, the crosectional area of the manifold should remain equal until it reaches the open plenum area.
The "shade tree" way to maximize this is to make the exhaust manifold slightly bigger in crossection than the port.
Also, the crosectional area of the manifold should remain equal until it reaches the open plenum area.
For all of us guys with more time than money- it could be a perfect weekend- bloody greasy knuckles and money for beer instead of parts.
#47
05-21-2009
Not trying to be negative.But don't headers provide more efficient scavenging of the exhaust gasses?
I thought that was the main reason the primaries are all different lengths to time the exhaust pulse.
This is something a stock log manifold can not do.
Each primary on my JBA's are as big as the main portion of my stockers.
Excluding your Lighting Rich.
I also made great power on my Cobra with stock manifolds[585 WHP].But I gained a touch over 26 WHP when I installed the Kooks long tubes and catted X-pipe.
Tony
I thought that was the main reason the primaries are all different lengths to time the exhaust pulse.
This is something a stock log manifold can not do.
Each primary on my JBA's are as big as the main portion of my stockers.
Excluding your Lighting Rich.
I also made great power on my Cobra with stock manifolds[585 WHP].But I gained a touch over 26 WHP when I installed the Kooks long tubes and catted X-pipe.
Tony
#48
05-21-2009
Well - The biggest ease on installment - is a body lift. I -really- wish I had my body lift on BEFORE I went to do the headers - Pulling the old manifold out was easy.. its trying to get the new JBA in thats the ***** lol. IKts a maze, and you have to go from the top of the engine down to the side - no way you can fit it in from the side or anywhere. As mentioned above - if you are good with your tools and get a little bit of penetrating oil to the situation, anywhere from 5-10 hours will cover you; 5-10 giving room for breaks, lunch/dinner, and some beer
Edit: Remember to keep an extra handful of Ouch tools on hand nearby; you dont want to go throwing away the tool you need every time you feel the need to throw one after banging your knuckles real good
Edit: Remember to keep an extra handful of Ouch tools on hand nearby; you dont want to go throwing away the tool you need every time you feel the need to throw one after banging your knuckles real good
#49
05-21-2009
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#50
05-22-2009
They take an educated guess at the shape that'll fit all the engine rooms. Then they do CFD (computational fluid dynamic) studies and tweak the interior surfaces to equalize the pressures (delta P) across the exhaust valves.
Basicly it's more a result of other criteria than it is in making the best power.
One small thing they can do with castings that you can't with headers.. is to make each primary and collector have a ever increasing crossectional area. Cut one apart and you'll see what I mean. This is a small way to help create that volume. (the same principal works for nearly any pumps exhaust side. Water, fuel, air, ect..)
If a feller has the funds to do both.. then more power to ya. (pun intended)
btw, I had a set of 3" LT headers for my Lightning. But I'm laid off and needed the cash. So I sold them and did the best I could with my stock iron manifolds. If I ever again have the spare cash.. I'd love to have a set of Kook LT and high flow cats. But as you know.. those puppies are not cheap.
Regards, Rich
