Shooting for 400HP, Need Bigger Exhaust?

[MuscleJunkie]

Emission here suck and Colorado seems to be going to the ways of Commiefornia. We see a move in our future, at least out of the metro area and emissions testing but for other reason as well. Crime is up, they let dangerous drug addicted mental health people camp on the street here, and they want to build and are building section 8 housing into the suburbs. We worked all our life to get this house and away from scum.

I AM YELLING!!!! I do not get requiring CARB original OEM style parts when I could put on 2 hi flow, high efficiency cats and run clean. Emissions matter to me and that is what they test. If emissions parts are there and she is running clean they shouldn't care beyond that!

I could cam-up and get 400 but would loose the low end torque I like. It is fast off-the-line for a heavy brick. Not interested in camming-up and getting a high stall torque converter to get it moving. Then, for what it is, it would still have a constipated exhaust. The exhaust is not built for 400HP but I am going to get a bit more out of it. The 2 1/2" downs with larger cats will wait till we move.

I am sure a custom cam for supercharging would help, so would larger heads and I could keep most of the torque, but I would loose mileage. I actually get Explorer mileage if I keep it out of boost.

It's been interesting - but I've also observed the my gas mileage has also improved since installing the Powerdyne and WTA intercooler.

 

[Fix4Dirt]

It's been interesting - but I've also observed the my gas mileage has also improved since installing the Powerdyne and WTA intercooler.

probably, since you usually don't have to push the pedal as hard, lol

 

[410Fortune]

could also be because hes driving around above 5280' in elevation...........

it takes like 2-3 psi of forced induction to make it behave like it would at sea level.
There simply is not as much oxygen available to combust!
my dad ran 85 octane in his rx7 Turbo and his 96 Supra turbo....because in Colorado the 87-91 octane is a waste of $$$$$$$$ no oxygen to make the higher octane needed!

Best thing we ever did was move out of Colorado it was the right thing to do for me and my family for sure.......and the 4 other families that followed us!! hahahahaha thriving up here

 

[Mesozoic]

Colorado's a nice place, just a high altitude place that imparts certain challenges on its inhabitants. That sucks that the place has started to use CARB requirements up there. I wonder if/when Arizona, Utah and New Mexico will follow suite. One workaround is to obtain collector car insurance. It makes the vehicle exempt from vehicle emissions, however it is not intended for daily driving.

I'm also after the 400 hp target, but would happily settle for 350+. Having built several forced induction SBFs, I decided to go N/A on this build. It's basically a slight bump up in compression, larger heads, intake and cam to match. I also intend to run true dual 2.5" exhaust out, not sure about whether retention of the 4 cats is going to be necessary or not. The sensors can be tuned out in the EEC-V, but thus far they have not been checking the undercarriage for cats, only the OBD-II output. I'm also planning to upgrade the transmission slightly, use a slightly higher RPM stall converter with a billet clutch and may increase the gear ratios to 4.11:1.

One of my biggest issues right now th at is the TM headers are nowhere to be found, despite being given a 10-12 week lead time, they should've been delivered by Christmas '22. I have until March to leverage Paypal for a refund, but not sure whether I should or not.

 

[410Fortune]

It has been taking 4-6 months to get TMH delivered
Robert told me if the site is up an accepting orders they are still making and shipping them
Last set we ordered arrived in 6 months but they arrived (August 22)
I believe many moons ago they were tested to be good to 420 crank hp of something around that mark
He used to have the ability to make sets with larger tubes, I don't think that is still a thing.

 

[CDW6212R]

It has been taking 4-6 months to get TMH delivered
Robert told me if the site is up an accepting orders they are still making and shipping them
Last set we ordered arrived in 6 months but they arrived (August 22)
I believe many moons ago they were tested to be good to 420 crank hp of something around that mark
He used to have the ability to make sets with larger tubes, I don't think that is still a thing.

What I recall was he was able to make the same headers with one size larger collector, he could make it a little larger there at the outlet. That can help but the down pipes have the stock size inlet opening too, so it's hard to gain much there without reworking the entire pipe etc.

 

[Blown]

Colorado adopted about 50 years of California emissions overnight! I don't get is that there is no grandfather clause for all the existing modified vehicles. I read an article and an estiamted 500,000 vehicles effected! We should be grandfathered as long as we are running clean and have all the emissions components...........................................enough *****ing.

My rig has passed the last two years by doing a drive by. Colorado Air Care sets-up sniffers around the metro area and I have not had to take it in in the last two years.

I did a bunch of reading and research yesterday. Everything has to be CARB approved from the air box through to the cats. The Supercharger is CARB approved as are the TMH headers. If I have to test in July, I do not have a CARB approved T-body nor Air Box. I think I will run it a few days on the original airbox and throttle body. My tuner is hidden, that only leaves Green 46lb injectors for them to notice.........I should be able to pass as all the emissions components are there and working.

Mileage, yup it's 5,400' at my house and I am running heavier AT's 255/70's. It is hard to keep out of boost when there are hills to climb all around. When in boost I am running 11.6 at the start to 11.2:1 fuel at full boost. That's using more of the wonderful God given petrol that has lifted everyone's standard of life simply because such a resource is available to us!

 

[Blown]

This is two builds ago, a 351W in an F150 with headers, big exhaust, stock truck roller cam, and Kenne Bell 2.1liter at 9lbs of boost.

I wanted to post this to illustrate all that torque there a little over 2000rpm, it's there earlier as well, and what a nice flat curve. The boost is there early with positive displacement superchargers and Kenne Bell is one of the most efficient. This illustrates the blow low concept. This to keep some mileage and get moving fast when driving a 4,000lb plus rig versus a 3,000lb car.........................................This blow low concept is one that most dyno's do not account for. Like why does the graphing of power start above 2,000rpm? Because most dyno's are set-up for cars, higher revving engines, bigger cams and perhaps higher stall torque converters and larger exhaust.

 

[Blown]

Found this Calculator for headers: Primary Header Tube Length and Diameter Calculator I have run some comparisons below with Boost with much higher VE than NA engines. My Volumetric Efficiency Numbers VE are guestimates at 5lbs, and 9lbs of boost. I wanted to compare cams for exhaust requirements. This illustrates the increase in air flow with the larger E303 cam. It would require larger headers and exhaust with boost. Ford Racing says a higher stall TC is recommended.

Based on these calcs, the TMH headers are good to what would be around 350 horses, at 5,000rpm with the stock cam, but some power is lost with shorty's shorter primaries.

Calc. Results
Calcs. based on the Stock Cam at 5,000rpm and VE of 130:
Your Primary Tube Length is 44.64
Your Primary Tube Diameter is 1.50 inches
Your Collector Diameter is 2.60 inches Two Collectors
E303 5,600rpm:
Your Primary Tube Length is 40.40
Your Primary Tube Diameter is 1.58 inches
Your Collector Diameter is 2.74 inches Two Collectors

Calc. based on the Stock Cam at 5,000rpm and VE of 155:
Your Primary Tube Length is 44.64
Your Primary Tube Diameter is 1.58 inches
Your Collector Diameter is 2.74 inches Two Collectors
E303 5,600rpm:
Your Primary Tube Length is 40.40
Your Primary Tube Diameter is 1.66 inches
Your Collector Diameter is 2.89 inches Two Collectors

Results Ford Racing E303 for NA engine
Calc. based on the E303 at 5,600rpm, VE of 90 for an NA engine:

Your Primary Tube Length is 40.40 Your Primary Tube Diameter is 1.43 inches Your Collector Diameter is 2.48 inches Two Collectors

I didn't know this: "Torque Monster Headers utilize 4 tubes into 1 collector, firing in circular order into the collector promoting scavenging into the exhaust pipe. Modified merge collector technology is utilized in the collector to prevent premature exhaust expansion before entering the exhaust pipe."

5.0L Truck, Explorer Camshaft F4TE-6250-BA
Advertised Duration: 256 / 266
Ex: F4TE-6250-BA
Cam Lift (Exhaust): .279''
Cam Lift (Intake): .263''
Cam Timing at .050'' Lobe Lift (Exhaust Close): 15 Deg BTC
Cam Timing at .050'' Lobe Lift (Exhaust Open): 32 Deg BBC
Cam Timing at .050'' Lobe Lift (Intake Close): 31 Deg ABC
Cam Timing at .050'' Lobe Lift (Intake Open): 25 Deg ATC
Duration at .050'' Lobe Lift (Exhaust): 197 Deg
Duration at .050'' Lobe Lift (Intake): 176 Deg
Lobe Centerline (Exhaust): 113 Deg
Lobe Centerline (Intake): 118 Deg
Valve Lash (Exhaust): Hyd.
Valve Lash (Intake): Hyd.
Valve Lift (Exhaust): .447''
Valve Lift (Intake): .421''

Ford racing E303
RPM Range 1600-5600
Int. Duration Advertised (Deg) 282
Exh. Duration Advertised (Deg) 282
Int. Duration @ .050 in. (Deg) 220
Intake Duration at 050 inch Lift 220
Intake Valve Lift 0.498 in (12.649 mm)
Intake Valve Lift with Factory Rocker Arm Ratio 0.498 in
Exhaust Valve Lift 0.498 in
Exhaust Valve Lift with Factory Rocker Arm Ratio 0.498
Lobe Separation (Deg) 110
Valve Springs Required - Yes
Valve Lift with Factory Rocker Arm Ratio
0.498 int./0.498 exh.
Advertised Duration
INT Open 0 Exh Open 40
Lobe centers are both 110

 

[Josh P]

I like the feeling of 400+ lb/ft of torque off idle

 

[410Fortune]

I did not know that either!!
I had E303 cam in my old 96 man that thing sounded so wicked cool even naturally aspirated. I never upgraded the springs though and that was a bad idea, the stock valve springs suck (it was noisy)

 

[CDW6212R]

Here's a good power tip, never use a Ford letter cam, next, no single pattern cams. Fords all have poor exhaust ports, they all need dual pattern cams. Dual pattern cams help a lot compared to single pattern cams, the extra lift and duration get the exhaust out better than the intake specs.

The stock manifolds, and the TM headers, both have basically no collectors, the pipes, two or four, all come together into one extremely short space. A proper merge collector combines the pipes over a short distance of 2-6" depending on primary and collector size. Proper merge collectors have a single spot where the pipe is smaller than where the pipes come together. The Explorer has no room for that good type of collector, given the location of the down pipe ball connection. If the connection could be moved downward along the down pipe path a little, then a merge area could be made slightly longer.

Without a decent merge area, any header is doing little scavenging, that happens along the distance where the primaries merge. So in a space the size of a tennis ball, not much is gained there. They(TM) should have spent more time developing the collector, the merge area, then trying to use up the engine bay to make the primaries the same length. I plan to join the four pipes near the stock location joint, but move the connection back a few inches, placing an actual merge collector there(cut shorter of course).

Go look at merge collectors which you can buy, to make your own headers. Note that they are relatively long, say 6-12", the pipes enter the front opening, then it shrinks slightly in diameter, and then it opens back up to the full collector pipe size. Those are what produce extra HP from headers, the merge area. OEM manifolds, nor TM headers, have anything like those built into them.

 

[Josh P]

The Ford letter cams were ok when they were new. The simulation software that is used to design cams is impressive and has been around for at least 15 years.

 

[CDW6212R]

Ok was fine in the mid 90's when those letter cams were made, I road in my first Fox Mustang with an E cam in 1996. It was fun and load, my friend had the typical Flowmasters, Edelbrock performer heads and intake, plus LT headers. I helped him test it in the 1/4, I won a VC2000 which is accurate on flat straight road. It was a low 14 second car, about 14.4 as I recall. My friend wasn't happy with that, he spent over $2300 for those parts, plus no PCM tuning. I think he had an adjustable FPR, which is a poor way to tune of course. But that's how it was done in the 90's.

The best cams come from expert custom cam designers, not from software to do it yourself, or a cam tech line. The cam tech lines were the standard back then 30 years ago. Custom cams have always been much better, and the price of them has always been about $100 plus different valve springs etc. People are cheap, spending $1000 is easy; but they would prefer to gamble to save $100 and go with any other cam choice but custom.

 

[Josh P]

Ok was fine in the mid 90's when those letter cams were made, I road in my first Fox Mustang with an E cam in 1996. It was fun and load, my friend had the typical Flowmasters, Edelbrock performer heads and intake, plus LT headers. I helped him test it in the 1/4, I won a VC2000 which is accurate on flat straight road. It was a low 14 second car, about 14.4 as I recall. My friend wasn't happy with that, he spent over $2300 for those parts, plus no PCM tuning. I think he had an adjustable FPR, which is a poor way to tune of course. But that's how it was done in the 90's.

The best cams come from expert custom cam designers, not from software to do it yourself, or a cam tech line. The cam tech lines were the standard back then 30 years ago. Custom cams have always been much better, and the price of them has always been about $100 plus different valve springs etc. People are cheap, spending $1000 is easy; but they would prefer to gamble to save $100 and go with any other cam choice but custom.

The software I'm talking about is what the cam designers use.

 

[Blown]

Don,
Good you brought-up the lack of real "collectors" on the TMH as well. There is a bit of one on the passenger side, but drivers is absent. I have seen much longer collectors, which are a big part of scavenging and they are pretty much absent on TMH's. I suppose the 2 1/4" downpipe would act as some type of relief for some scavenging.

I wouldn't run an alphabet cam either. but the E303 has been used so is a decent point of comparison. Yup, smaller exhaust valves and a boosted engine = need for more exhaust time and volume.

I had to look-up altitude effect again for amount, is 3% per 1000' of gain or 15% loss here for NA engines. 210hpX.85 = 178.5 or 31.5 horses lost.

Boost is 15-19 horses per pound. You get less boost at altitude because the compressor is starting with thinner air, but the boost you see on the gauge and in calculations is boost above 14.7psi...........................The 9psi it makes here is 11.23lbs at sea level.

 

[CDW6212R]

Don,
Good you brought-up the lack of real "collectors" on the TMH as well. There is a bit of one on the passenger side, but drivers is absent. I have seen much longer collectors, which are a big part of scavenging and they are pretty much absent on TMH's. I suppose the 2 1/4" downpipe would act as some type of relief for some scavenging.

I wouldn't run an alphabet cam either. but the E303 has been used so is a decent point of comparison. Yup, smaller exhaust valves and a boosted engine = need for more exhaust time and volume.

I had to look-up altitude effect again for amount, is 3% per 1000' of gain or 15% loss here for NA engines. 210hpX.85 = 178.5 or 31.5 horses lost.

Boost is 15-19 horses per pound. You get less boost at altitude because the compressor is starting with thinner air, but the boost you see on the gauge and in calculations is boost above 14.7psi...........................The 9psi it makes here is 11.23lbs at sea level.

I have enjoyed some of the recent Engine Masters TV shows that have had boosted engines in the episodes. They seem to often get near 50% power gains from half an atmosphere of boost. So they detuned some monster blower to only produce 8.5 psi of boost, and jump the engine from 530 HP to just under 800 HP. They sometimes achieve power/boost figures that are way above the book predictions.I read the 15-20hp/psi figures too in various predictions online, forums or other shows. Obviously there is no real good rule of thumb. I know a well known and respected Corral member who is part of the Pinks show, who has a street Ford(Fairlane I think), with a 365 SBF and about 9-10psi of boost. It makes about 900hp(chassis dyno, not engine), so he is way way above any typical rule of thumb. He has a thread that is kind of old now, that shows his progress on that car, NA, and then as he built the intercooler from copper tubing and AL, feeding a TFS R intake(full length version). That to me is a high standard to shoot for, full time street and reliable, plus scary fast.

 

[CDW6212R]

The software I'm talking about is what the cam designers use.

The top custom cam designers do not simply plug in variables and produce the cams that they sell. You cannot use any software and duplicate what they sell. They have special expertise in how those car specs affect the engine's need for duration and cam timing, lift etc. If you or I could skip them and order the same cams as they sell, then they would not be as widely respected as they are(plus they'd be out of the cam business). Ed Curtis has countless customers that don't doubt his ability to sell them the best cam possible for their vehicles. It's nice to talk about the cam software, and use it to get an idea of what a great cam might be close to in specs. But don't discount the results of the real pro's cams. I will gladly pay them the extra $100, and install the valve springs that they tell me will be better than any random "good to .600" lift" springs that come with complete heads.

 

[Blown]

Don,

I have enjoyed some of the recent Engine Masters TV shows that have had boosted engines in the episodes. They seem to often get near 50% power gains from half an atmosphere of boost. So they detuned some monster blower to only produce 8.5 psi of boost, and jump the engine from 530 HP to just under 800 HP. They sometimes achieve power/boost figures that are way above the book predictions.I read the 15-20hp/psi figures too in various predictions online, forums or other shows. Obviously there is no real good rule of thumb. I know a well known and respected Corral member who is part of the Pinks show, who has a street Ford(Fairlane I think), with a 365 SBF and about 9-10psi of boost. It makes about 900hp(chassis dyno, not engine), so he is way way above any typical rule of thumb. He has a thread that is kind of old now, that shows his progress on that car, NA, and then as he built the intercooler from copper tubing and AL, feeding a TFS R intake(full length version). That to me is a high standard to shoot for, full time street and reliable, plus scary fast.

I'd like to see what you eventually build. For all you put-out here, I see no active build?

The rule of thumb, I spoke of, 15-19 horses per pound of boost is gleamed from Kenne Bell's work with the 5.0 in Stangs. It applies pretty well here. It is a range because the boost depends on the other power adders on the build.

I am realistic. I do not aspire to make an Exploder like a muscle car, not going to happen without way too much work, expense and then you still have a 4,000lb brick on a sub par suspension..........................................With Blow Low I am getting 400ftlbs off idle, don't need a big cam, big exhaust and can get a bit of mileage out of her. I would have a Mustang if I wanted that much go fast.

I think you're old school. There are excellent computer programs for building engines and testing them virtually. I totally believe in them as much as someone with hands on experience. The programming is expensive or I would have it. Laugh at the affordable Desktop Dyno 2000, a simpler version of the professional programming, but it is a very useful tool. I used it to profile many different cams and to make my decisions long ago about what to build for 4wheeling and moving a heavy brick. I don't think you got your welcome to the computer age?

 

[CDW6212R]

Yes I am old school, I haven't been around much racing here other than 20 years ago when we used to go to our two 1/8 mile tracks a lot for a couple of years. I try to see what works for others and learn from it, as everyone does. But I also look for details that make a bigger difference than the popular common ideas or tricks.

I just spoke to a man yesterday who was part of the development of the KB kits on the Fox Mustangs, when they were using 1.5/1.7 and he said a 1.8 blower. Not commonly known, but they finally hit over 500rwhp in a Fox Mustang, without an intercooler, using the GT40 intake and KB plenum. The stock block didn't survive long after the project was done, but he said the biggest problem they had was the exhaust. They ended up with 1.75" long tube headers, no cats, and 2.5" dual pipes back to the bumper. I think they were constrained by the intention of KB for much of the engine and parts. The heads were Dart, and they had to push the blower rpm to get 16psi of boost, again without an intercooler. He said forcing the air in wasn't the problem, it was the high heat from the back pressure of the exhaust, and they had to over build the fuel system and pumps to get the A/F ratio rich enough to avoid detonation.

That was a big achievement back then for sure, but there aren't examples close to that since then, as I said about 400rwhp is the typical max hp you see from a KB on a Fox Mustang. The exceptions were the custom A2A IC's that were added by welding the KB plenum to divert the airflow out the left side, and eventually back into the plenum above the GT40 lower side.

What I learned from that expert conversation was that the 2.2 blower is not likely to push 500hp at good blower rpm, and I'm not going to make it run 18,000rpm(the recommended limit). I want it down in the low teens, 12-13,000 rpm at the shift point I think would last a long time. Given what KB makes, that leaves the 2.6 size for me, so hopefully I can retire and start this Fall.