Supra intake hard pipe?
- Thread starter DIASISS
- Start date
Pretty sure he's talking about a GE. In which case, theres nothing wrong with stock, with very minor (if any) gains to be had with swapping to a hard pipe.
Sent from my HTC Droid DNA
Sent from my HTC Droid DNA
Old rubber can be replaces by silicone couplers. 2" IIRC. You actually don't want to get to get rid of the "silencer" it improves air flow to the intake plenum, particularly at mid to high RPM.
It's been a long time since I did this for my '89NA, but from memory:
A 2" 45 degree silicone coupler from throttle body to "silencer" (Actually a harmonic chamber.)
A 2" straight coupler to a short piece of 2" pipe. I seem to recall that I used some exhaust pipe, painted black.
I used some of the stock rubber to connect it to the AFM... Maybe I bought a reducer later, but I don't remember the dimensions.
It's been a long time since I did this for my '89NA, but from memory:
A 2" 45 degree silicone coupler from throttle body to "silencer" (Actually a harmonic chamber.)
A 2" straight coupler to a short piece of 2" pipe. I seem to recall that I used some exhaust pipe, painted black.
I used some of the stock rubber to connect it to the AFM... Maybe I bought a reducer later, but I don't remember the dimensions.
Dan_Gyoba;1963060 said:
I was considering finding a hard pipe solution for my GE intake due to the fact that mine is falling apart as well as being bulky and ugly as hell. How much of a negative effect would an aftermarket solution have on the intake in your opinion. Would it decrease horsepower and fuel efficiency?
Keep in mind that I haven't done the measurements myself, I'm taking flow graphs done by other people.
The effect is not large, but there is a marked decrease in torque in the upper mid range RPM band, and a smaller drop in the off-idle range. Top end is reasonably unaffected, and may get somewhat better with larger tubing, say 2.75" which is (I think) the approximate size of the throttle body and AFM outlet, but that wasn't how the tests were done, it was pure speculation at that point.
Despite all the blue silicone under my hood, I've never been one to care too much about what engine stuff looks like, I'll take performance over looks every time. It is nice if you can have both though.
In terms of actual performance, you're probably looking at tenths of seconds in a quarter mile, maybe a couple of decimal points for mileage. The seat of the pants probably won't notice a difference, and you may even feel like it's faster, due to the increase in engine noise. This would still be a loss though, even with potential top end gains.
Just keep in mind that as far as performance goes, I pretty much left the 7M-GE alone. My sole "mods" were a K&N drop-in filter (Which I still have, as it happens) and a 2.5" manifold-back exhaust. The filter was done because a washable filter is cheaper long-term, and the exhaust was close to the cheapest that I could get done. I did nothing else at all that would affect performance, but I certainly wan't going to do something that would HURT performance either.
So really, we're splitting hairs. I just dislike the idea that people want to get rid of "restrictive factory" stuff erroneously. Like someone at Toyota was thinking "Hey, this is our flagship sports car. Let's make it slower and more mild mannered, because that's what our sports car customers REALLY want in a car..."
The effect is not large, but there is a marked decrease in torque in the upper mid range RPM band, and a smaller drop in the off-idle range. Top end is reasonably unaffected, and may get somewhat better with larger tubing, say 2.75" which is (I think) the approximate size of the throttle body and AFM outlet, but that wasn't how the tests were done, it was pure speculation at that point.
Despite all the blue silicone under my hood, I've never been one to care too much about what engine stuff looks like, I'll take performance over looks every time. It is nice if you can have both though.
In terms of actual performance, you're probably looking at tenths of seconds in a quarter mile, maybe a couple of decimal points for mileage. The seat of the pants probably won't notice a difference, and you may even feel like it's faster, due to the increase in engine noise. This would still be a loss though, even with potential top end gains.
Just keep in mind that as far as performance goes, I pretty much left the 7M-GE alone. My sole "mods" were a K&N drop-in filter (Which I still have, as it happens) and a 2.5" manifold-back exhaust. The filter was done because a washable filter is cheaper long-term, and the exhaust was close to the cheapest that I could get done. I did nothing else at all that would affect performance, but I certainly wan't going to do something that would HURT performance either.
So really, we're splitting hairs. I just dislike the idea that people want to get rid of "restrictive factory" stuff erroneously. Like someone at Toyota was thinking "Hey, this is our flagship sports car. Let's make it slower and more mild mannered, because that's what our sports car customers REALLY want in a car..."
An intake pipe for a mid 90's civic worked great when my car was NA. The pipe had a 45 degree angle near the top. I had pics around here somewhere...
I had replaced mine with straight pipe back when i was NA, and didn't notice any change, good or bad.
But if yours is falling apart, no harm in doing it. And yes, i had heard that a honda intake would fit. Thought it was for a
90's accord.
But if yours is falling apart, no harm in doing it. And yes, i had heard that a honda intake would fit. Thought it was for a
90's accord.
I made a custom pipe, 45 deg. elbow, 15 deg. pipe.
You can also check out this build by Ryan, he used a 60 deg. elbow, straight pipe.
http://www.supramania.com/forums/showthread.php?158342-Ryans-ma70-supra/page14
You can also check out this build by Ryan, he used a 60 deg. elbow, straight pipe.
http://www.supramania.com/forums/showthread.php?158342-Ryans-ma70-supra/page14
To be perfectly honest it's been years since I had my Supra & I miss it dearly but you need money to keep any car going & I was always broke.
However. To be perfectly honest. You don't want a pipe. I was actually thinking over the volumetric efficiency of the 7m-ge, its a great engine but I don't think Toyota, followed some racing principles at the time to yield peak horsepower from the 3.0L inline 6 cylinder engine. It should make a good deal of power. However that power seems to lack the top-end pull...
Lets address this, & yield as much as 20 horsepower by optimizing the velocity (less air at higher density moving at higher speed) vs Big long 3" pipe to AFM which has big volume like a big Diesel Truck (Lots of air volume requires lots of fuel terrible fuel economy on top of zero big end power)...
So winning as we know is top end power, you can't win a race if you have grunt in the mid band & nothing on the top end. We need VELOCITY to achieve winning performance, high rpm top end power VS high VOLUME which is for pulling a house or a big trailer not racing, which is what we want... You can achieve big torque by lengthening the intake pipe + going bigger like 3.25-3.5" to achieve big torque on the ultra low end but no big end power at all. It'll fall on its face at 4,500rpm & make nothing up top.
Don't you want to have precise throttle precision & optimal fuel efficiency by reducing the VOLUME & Increasing the Velocity rather? Means less air very dense moving really fast, much faster into the engine than Volume (Cold air intake long piping for instance). We need to shorten the distance of intake inlet components as close to the inlet as possible & also optimize the size of everything. Its more important to reduce volume than reduce intake charge temperature with massive volume ie no big end power.
(7M-GE)
204 hp @ 6000 rpm
196 lb-ft. of torque @ 4800 rpm
In. Valves 32mm/1.26 in
Ex. Valves 27.5mm/1.08 in
Optimal stock 7M-GE performance would be to mathematically find the ideal parameters to the size of the inlet & outlet size. They use this methodology in Formula One racing & Over at Honda & Jet Engine Technology at places like Pratt & Whitney.
If there are 12 intake valves at 32mm each, take 32mm x 12 valves divided by 6 cylinders = 64mm is optimal for the 3.0L 6 cylinder engine for intake inlet size. 64mm to inches is 2.519685 Inches
If there are 12 exhaust valves at 27.5mm each, take 27.5mm x 12 valves divided by 6 cylinders = 55mm is optimal for the 3.0L 6 cylinder engine for exhaust outlet size. 55mm to inches is 2.165354 Inches
So to achieve maximum 7M-GE performance, requires inlet diameter no greater than 2.5" & outlet diameter of no more than 2.0" (going smaller will ever further increase throttle response & high rpm power on top of great fuel efficiency.
Knowing this we can achieve Stoichiometric AFR (Most Optimal AFR Air Fuel Ratio at All RPM points) It should keep you planted in the seat hard clear to the rev limiter if done perfectly & perfectly sealed exhaust & intake (CANNOT LEAK NOT 1 IOTA) I would go ahead & replace the exhaust & intake manifold gaskets along the whole engine & all vacuum lines as well.
OBX Motorsports has 2" downpipe headers which is optimal, must match with 2" exhaust piping as well through a Magnaflow Resonator 24" 2" to 2" to a Dual Slanted Tip Muffler
We could yield 240 horse power if its 110% leak free & done precisely correct diameters.
Just to talk mathematically as far as achieving perfect air readings from the air flow sensor were taking it down on the inlet of the air & the outlet. 2.75" vs 3.00" on the inlet of the afm = 9% & 2.5" on the outlet vs 3.00" = 20% dudeski's :supra1000:! So in total we achieve 29% exactly greater efficiency & if you custom engineer a 2.5" afm adapter we achieve a crazy 40% greater power & efficiency. It will have such immense pressure on the IACV Intake Air Control Valve switching the intake path from long valve closed above 62% throttle input past about 4,000 rpm & switch to short path runner's allowing great high rpm power because of the increased volumetric efficiency over the single inlet GTE intake manifold
If we could potentially achieve 40% more horsepower from changing the afm inlet & outlet sensor readings, can change the character of the car forever. Its amazing dudes, 40% more efficienct & yield greater go power than the magnificent 2.2L DOHC 16 valve VTEC H22A1 engine that smoked my supra back in the day clear out past 120mph, super dogging in the redline as the H22 is rapped out clear past 7,500rpm pulling out to 140 like a champ. This will change the whole dynamic of the so glorious & improperly engineered Toyota engine dual over head cam 24 valve inline 6 at 3000cc output vs 2200cc H22. With 40% greater increase on the afm cfm & an additional 25% on the exhaust from 2.5" to 2" is 25% greater pressure in the combustion chamber, means a hotter burn on the optimized inlet & exhaust. So much more fun dudes the engine is going to run unreal like this, a change we've been waiting for on the 7m-ge that never could impress like we really wanted. Getting smoked by an 80s BMW 535is 3.5L inline six, with its stronger big end. Now we can achieve potentially 336.6 horsepower, truly i say unto thee.
Design a mount brace to relocate the afm to directly at the throttle body with couplers & add afm adapter & high airflow cleanable foam air filter... This way you can clear hear the secondaries bang in @ 4,000rpm wide open in gear, you can hear it switch intake paths & short ram helps increase velocity & reduce volume for better fuel efficiency & way better performance down low & up top.. looking forward to the results buddy! It sounds so awesome hear the hissing of the changes in throttle input & wide open growls so nice.
Zero restriction air filter
https://www.ebay.com/itm/3-Mushroom...ash=item466ca6b3f5:g:qDMAAOSwySlaFdzi&vxp=mtr
Toyota is using a 2.5" throttle body which is optimal as per the math & the AFM is 3" on the outlet which is why it get terrible fuel economy/ poor response & poor performance, so coupling 3" to 2.5" will further increase velocity & reduce wasted pressure & achieve more efficient running & more power.
2.5" pipe & Also add a mounting bracket weld it to the pipe so the AFM doesn't droop the couplers & you'll want to tap a fitting on for the PCB smooshed between the AFM & the Throttle Body... Might need to cut the ends off to shorten as much as possible & even just go to an exhaust shop & make it like 3" long shorter the better tight fit ... This is high precision engineering.. Let's do that Intake Right Brother! Have then cut a 2.5" ID-OD whatever 2.5" & at 3" long & bring a fitting for the PCV Hose very important to feed that in after the AFM (keep afm clean & keep pressure low in the crankcase also further improve economy by sucking down fuel vapors from the blow by
https://www.ebay.com/itm/3-4-PLY-ST...ash=item23592552df:g:k9QAAOSw9gRaMIaq&vxp=mtr
You'll need a 3" to 2.5" coupler from outlet of AFM to the 2.5" pipe for PCV & a 2.5" to 2.5" coupler from the 2.5" pipe to the 2.5" throttlebody (PERFECT DUDE!)
https://www.ebay.com/itm/3-to-2-5-S...ash=item1a4565f7c7:g:nxEAAOSw49lZt03L&vxp=mtr
https://www.ebay.com/itm/2-5-3-PLY-...ash=item232c4b9e2a:g:IA8AAOSw~vpaBWhL&vxp=mtr
This AFM Adapter is said to be 2.75" so thats better & more velocity than 3" .. The smaller u go higher velocity less volume ie the meter reads less air means more economical, also by eliminating the long pipe, the AFM also reads a huge decrease in air volume & huge increase in volumetric efficiency & velocity, because the intake pipe length adds more Volume & lows the Velocity.. so we eliminate that & boost velocity to the MAX by keeping it all real tight at the throttle body
https://www.ebay.com/itm/2-5-64mm-A...ash=item1a45e2e9da:g:EoYAAOSwirdalluI&vxp=mtr
I cannot find a 2.5" afm adapter, if you can find one let me know, this one seems optimal as it channels air smoothly into the air flow meter
https://www.ebay.com/itm/AFM-Air-Fi...ash=item35c53347ac:g:2XwAAOSw3EVaVIJL&vxp=mtr
However. To be perfectly honest. You don't want a pipe. I was actually thinking over the volumetric efficiency of the 7m-ge, its a great engine but I don't think Toyota, followed some racing principles at the time to yield peak horsepower from the 3.0L inline 6 cylinder engine. It should make a good deal of power. However that power seems to lack the top-end pull...
Lets address this, & yield as much as 20 horsepower by optimizing the velocity (less air at higher density moving at higher speed) vs Big long 3" pipe to AFM which has big volume like a big Diesel Truck (Lots of air volume requires lots of fuel terrible fuel economy on top of zero big end power)...
So winning as we know is top end power, you can't win a race if you have grunt in the mid band & nothing on the top end. We need VELOCITY to achieve winning performance, high rpm top end power VS high VOLUME which is for pulling a house or a big trailer not racing, which is what we want... You can achieve big torque by lengthening the intake pipe + going bigger like 3.25-3.5" to achieve big torque on the ultra low end but no big end power at all. It'll fall on its face at 4,500rpm & make nothing up top.
Don't you want to have precise throttle precision & optimal fuel efficiency by reducing the VOLUME & Increasing the Velocity rather? Means less air very dense moving really fast, much faster into the engine than Volume (Cold air intake long piping for instance). We need to shorten the distance of intake inlet components as close to the inlet as possible & also optimize the size of everything. Its more important to reduce volume than reduce intake charge temperature with massive volume ie no big end power.
(7M-GE)
204 hp @ 6000 rpm
196 lb-ft. of torque @ 4800 rpm
In. Valves 32mm/1.26 in
Ex. Valves 27.5mm/1.08 in
Optimal stock 7M-GE performance would be to mathematically find the ideal parameters to the size of the inlet & outlet size. They use this methodology in Formula One racing & Over at Honda & Jet Engine Technology at places like Pratt & Whitney.
If there are 12 intake valves at 32mm each, take 32mm x 12 valves divided by 6 cylinders = 64mm is optimal for the 3.0L 6 cylinder engine for intake inlet size. 64mm to inches is 2.519685 Inches
If there are 12 exhaust valves at 27.5mm each, take 27.5mm x 12 valves divided by 6 cylinders = 55mm is optimal for the 3.0L 6 cylinder engine for exhaust outlet size. 55mm to inches is 2.165354 Inches
So to achieve maximum 7M-GE performance, requires inlet diameter no greater than 2.5" & outlet diameter of no more than 2.0" (going smaller will ever further increase throttle response & high rpm power on top of great fuel efficiency.
Knowing this we can achieve Stoichiometric AFR (Most Optimal AFR Air Fuel Ratio at All RPM points) It should keep you planted in the seat hard clear to the rev limiter if done perfectly & perfectly sealed exhaust & intake (CANNOT LEAK NOT 1 IOTA) I would go ahead & replace the exhaust & intake manifold gaskets along the whole engine & all vacuum lines as well.
OBX Motorsports has 2" downpipe headers which is optimal, must match with 2" exhaust piping as well through a Magnaflow Resonator 24" 2" to 2" to a Dual Slanted Tip Muffler
We could yield 240 horse power if its 110% leak free & done precisely correct diameters.
Just to talk mathematically as far as achieving perfect air readings from the air flow sensor were taking it down on the inlet of the air & the outlet. 2.75" vs 3.00" on the inlet of the afm = 9% & 2.5" on the outlet vs 3.00" = 20% dudeski's :supra1000:! So in total we achieve 29% exactly greater efficiency & if you custom engineer a 2.5" afm adapter we achieve a crazy 40% greater power & efficiency. It will have such immense pressure on the IACV Intake Air Control Valve switching the intake path from long valve closed above 62% throttle input past about 4,000 rpm & switch to short path runner's allowing great high rpm power because of the increased volumetric efficiency over the single inlet GTE intake manifold
If we could potentially achieve 40% more horsepower from changing the afm inlet & outlet sensor readings, can change the character of the car forever. Its amazing dudes, 40% more efficienct & yield greater go power than the magnificent 2.2L DOHC 16 valve VTEC H22A1 engine that smoked my supra back in the day clear out past 120mph, super dogging in the redline as the H22 is rapped out clear past 7,500rpm pulling out to 140 like a champ. This will change the whole dynamic of the so glorious & improperly engineered Toyota engine dual over head cam 24 valve inline 6 at 3000cc output vs 2200cc H22. With 40% greater increase on the afm cfm & an additional 25% on the exhaust from 2.5" to 2" is 25% greater pressure in the combustion chamber, means a hotter burn on the optimized inlet & exhaust. So much more fun dudes the engine is going to run unreal like this, a change we've been waiting for on the 7m-ge that never could impress like we really wanted. Getting smoked by an 80s BMW 535is 3.5L inline six, with its stronger big end. Now we can achieve potentially 336.6 horsepower, truly i say unto thee.
Design a mount brace to relocate the afm to directly at the throttle body with couplers & add afm adapter & high airflow cleanable foam air filter... This way you can clear hear the secondaries bang in @ 4,000rpm wide open in gear, you can hear it switch intake paths & short ram helps increase velocity & reduce volume for better fuel efficiency & way better performance down low & up top.. looking forward to the results buddy! It sounds so awesome hear the hissing of the changes in throttle input & wide open growls so nice.
Zero restriction air filter
https://www.ebay.com/itm/3-Mushroom...ash=item466ca6b3f5:g:qDMAAOSwySlaFdzi&vxp=mtr
Toyota is using a 2.5" throttle body which is optimal as per the math & the AFM is 3" on the outlet which is why it get terrible fuel economy/ poor response & poor performance, so coupling 3" to 2.5" will further increase velocity & reduce wasted pressure & achieve more efficient running & more power.
2.5" pipe & Also add a mounting bracket weld it to the pipe so the AFM doesn't droop the couplers & you'll want to tap a fitting on for the PCB smooshed between the AFM & the Throttle Body... Might need to cut the ends off to shorten as much as possible & even just go to an exhaust shop & make it like 3" long shorter the better tight fit ... This is high precision engineering.. Let's do that Intake Right Brother! Have then cut a 2.5" ID-OD whatever 2.5" & at 3" long & bring a fitting for the PCV Hose very important to feed that in after the AFM (keep afm clean & keep pressure low in the crankcase also further improve economy by sucking down fuel vapors from the blow by
https://www.ebay.com/itm/3-4-PLY-ST...ash=item23592552df:g:k9QAAOSw9gRaMIaq&vxp=mtr
You'll need a 3" to 2.5" coupler from outlet of AFM to the 2.5" pipe for PCV & a 2.5" to 2.5" coupler from the 2.5" pipe to the 2.5" throttlebody (PERFECT DUDE!)
https://www.ebay.com/itm/3-to-2-5-S...ash=item1a4565f7c7:g:nxEAAOSw49lZt03L&vxp=mtr
https://www.ebay.com/itm/2-5-3-PLY-...ash=item232c4b9e2a:g:IA8AAOSw~vpaBWhL&vxp=mtr
This AFM Adapter is said to be 2.75" so thats better & more velocity than 3" .. The smaller u go higher velocity less volume ie the meter reads less air means more economical, also by eliminating the long pipe, the AFM also reads a huge decrease in air volume & huge increase in volumetric efficiency & velocity, because the intake pipe length adds more Volume & lows the Velocity.. so we eliminate that & boost velocity to the MAX by keeping it all real tight at the throttle body
https://www.ebay.com/itm/2-5-64mm-A...ash=item1a45e2e9da:g:EoYAAOSwirdalluI&vxp=mtr
I cannot find a 2.5" afm adapter, if you can find one let me know, this one seems optimal as it channels air smoothly into the air flow meter
https://www.ebay.com/itm/AFM-Air-Fi...ash=item35c53347ac:g:2XwAAOSw3EVaVIJL&vxp=mtr
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Do not use foam filters (there is a reason people called them HKS Dirtflow). They don't filter very well. Use a dry filter, like an AEM Dryflow.
Check this video out, notice you can hear the IACV change over at 4,000rpm, but it doesn't sing out properly to the rev limit... It should countinue to speed up as the engine rpm rises, burning ever hotter in the combustion chamber. Hotter burn means more horsepower. Try some 110 Royal Racing Fuel out on an empty tank, & let it eat haha
[video=youtube;FoVwgGuB9Kc]https://www.youtube.com/watch?v=FoVwgGuB9Kc[/video]
[video=youtube;FoVwgGuB9Kc]https://www.youtube.com/watch?v=FoVwgGuB9Kc[/video]
Do you have any videos on Youtube? I'd really like to see a video of the engine & how it runs & a POV spirited cruise would be cool.