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Arouse the DAMPFHAMMER!
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whats the gold wrap stuff?
Money making :D...come on, the absorbed heat of the intake from the engine is in the lower Watt region, the air velocity is at WOT about 10-40 m/s. This means, to heat the incoming air by 1 °C through engine heat radiation you need something in the low kW region (e.g. 30 m/s, 70 mm pipe, 0.19 kW)...that's a marketing gag, nothing more!

By the way, by using polished aluminium pipes, the difference in emission coeffcient is just (0.05-0.02) 0.03...but even without polishing (factor of 5 = 0.1/0.02) the absorbed heat is anyway in the lower Watt region...even you assume the engine has an emission coefficient of 1 (black body), which isn't the case, the temperature of the radiated heat is lower than 100 °C...there is no chance by using even the baddest viewing factors, the baddest radiation areas constellations, getting more then 100 W into the pipe is not real. Prove me wrong...I just did a small thumb caculation :D
 

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Don't drag math, facts, and data into a conversation involving belief and opinion, you'll lose everytime!
 

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Arouse the DAMPFHAMMER!
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Don't drag math, facts, and data into a conversation involving belief and opinion, you'll lose everytime!
Ok :D...

... it's 0.190 kW/°C for intake air heat up and about 0.007 kW at a viewing factor of the pipe-engine situation of 1 (LOL, Baehr's book formula gives one 0.13) via radiation...to loose measureable VE you need at least 2 °C of warmer air, for a ignition retard due to knock about the same if you have tuned it on the edge.

So, where are those 2 °C increase? Again, feel free to prove me wrong...if you have a measurement based validation, post it. If you have a calculation, post it. As you said, you have nothing to loose, me too, as I love to learn.
 

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Ok :D...

... it's 0.190 kW/°C for intake air heat up and about 0.007 kW at a viewing factor of the pipe-engine situation of 1 (LOL, Baehr's book formula gives one 0.13) via radiation...to loose measureable VE you need at least 2 °C of warmer air, for a ignition retard due to knock about the same if you have tuned it on the edge.

So, where are those 2 °C increase? Again, feel free to prove me wrong...if you have a measurement based validation, post it. If you have a calculation, post it. As you said, you have nothing to loose, me too, as I love to learn.
I think kb58 was being facetious.
 

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Arouse the DAMPFHAMMER!
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I think kb58 was being facetious.
Thanks man, very honest from you to spell it out for me and a nice word to know 'facetious'. I read it once more and yes, you are right. Could be read that mathematic and facts could contratict beliefs and opinions, but if believes and opinions has no room for the first it will be wasting of time to convince those with the first both :D.

I am sorry for misreading it kb58 :eek:. I really have to do further improvements of my English spoken and written language. Anyway, it did motivate me to estimate it in 2nd approach :D. Such coherences are always nice to know.
 

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Arouse the DAMPFHAMMER!
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Sorry, yeah I was... another term would be "smart ass"...
Not really kb58...didn't you know to be provicative is in the terms of philsophical doctrine of the Cynics just another way to recognitional...that would be being a smart ass saying :D...but it happens (the recognitional, see above) sometimes exactly that way :D
 

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my map pressure on k20a type r with rbc intake and stock throttle body with aem short ram air intake with 76mm tubing is 95kpa right before rev limiter. and the mid range map pressure is 99kpa. Do you think that I have a restriction at intake tube or throttle body ?

And does exhaust system effect map pressure also? I mean may be because of insufficient exhaust system engine can not breath more air and map presurre drop at high revs?



I partly agree with this...if there is a MAP drop at WOT that simply reveals a restriction to flow somewhere in the intake between the filter (or velocity stack) and plenum. Yes...it could be the throttle body, but the restriction could also be due to the intake tubing.

The MAP is simply measuring the pressure gradient across the entire length of the intake. Pressure (gradient) = flow (air) x resistance (of the intake).

Resistance is influenced by the LENGTH of the intake tubing as well as the cross sectional AREA of the intake tubing and throttle body. So, if there is a drop in MAP at WOT you cannot simply say it's the throttle body without entertaining the possibility that the intake is the actual restriction (unless you also simultaneously know the pressure just proximal to the throttle body).
 

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Arouse the DAMPFHAMMER!
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...map pressure on k20a type r with rbc intake and stock throttle body with aem short ram air intake with 76mm tubing is 95kpa right before rev limiter. and the mid range map pressure is 99kpa. Do you think that I have a restriction at intake tube or throttle body ?
The restriction is likely through air filter. In general 4 kPa is pretty much. Of course a bigger TB would help to increase MAP, but my guess is 30-40 mbar would be only possible if the transition is like a sharp corner from intake pipe to TB is done.

...And does exhaust system effect map pressure also? I mean may be because of insufficient exhaust system engine can not breath more air and map presurre drop at high revs?
No, not really. The MAP is created by the air pressure outside. The intake system reduces it by some restrictions like diameter offset's, lengths and so on. Even if the exhaust system works badly, the down running piston just suck air, but it doesn't add air. It's like the cylinder takes some volume out of the air outside and by flowing air through the intake system it adds it again. If the engine don't run MAP = pressure outside, that's the maximum you can reach in stationary view.
 

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i know this a littel off but how do u think 80mm tb would work on rrc intake???

Stock 62mm vs Blox 72mm vs ktuned 80mm on rrc mafold on a k20a2 with stock cams or even z1 cams, rdx 410cc an 3" exhaust????
I do not think the throttlebody is the major bottleneck in all of those scenarios. If your motor needs an 80 mm throttlebody, then the stock intake manifold and stock cams are going to be a bigger bottle neck. IMHO
 

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Arouse the DAMPFHAMMER!
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A revival :D

I do not think the throttlebody is the major bottleneck in all of those scenarios. If your motor needs an 80 mm throttlebody, then the stock intake manifold and stock cams are going to be a bigger bottle neck. IMHO
Yuup :up:

Does anyone ever prove that 80 mm TB supported the engine for more power? Or the other, less power? Joe McCarthy made measurements with up to 80 mm TB size and showed it helped for more, but his engine setups where able to breath more. I would also like to see the TB angle vs MAP log...low load tuning for emissions seems to me a challenging task.
 

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Back from the dead... I am glad I found this thread. I have been debating Maxbore again vs 70mm. I am using a ported and polished RBC with massage Runners and port matches to the PRB head. While the plenum is off the RBC IM, it is test fit and aligned with a Hondata IMG. From previous RBC IM jobs I have found variances between 2002-2004 & 2005-2006 PRB intake ports - when I install the IMG'S. The ports simply do not always line up. Cylinder #1 being worst, cylinder #2 - #4 get progressively better.

I am pretty sure Hondata has their IMG CNC made. Yet when I reinstalled the OEM gaskets on some off these heads just for studying reasons, the intake ports are still off. This isnt on every head. But when Ihave seen about 60% of the port being off and at the worst spots 3/32"-5/64" off. That is a huge amount of negative pressure being created from that kind of lip and an obstruction. I wonder if the term "factory freak engine" making more HP than other equal part engine has anything to do with perfect port Matching from the production line.

I do believe a throttle body increase may not produce great results with one of these heads. The fact having the RBC's plenum off, a correct port match can be completed. I was not aware of how many people knew this. Before I install a thermal gasket as well I scribe lines to the intake manifold flange to keep it right before going blind on the final intake manifold install with the plenum welded back on as well.
 

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Arouse the DAMPFHAMMER!
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...The ports simply do not always line up. Cylinder #1 being worst, cylinder #2 - #4 get progressively better.
Beside that the misalignment of the flow due to the thickness of the gasket - it's wall has no 15° angle like the port has - flow is always off an alignment. Beside that there is still no evidence those insulation gaskets can improve knock margin distance or increase the density on WOT. My calculation of an inflow process shows for the ideal case of the IM has the same temperature as the air, the difference in density to the stock gasket is lower than 1 °C. This means, this would be no measurable effect on knock margin at WOT. On part load the story is different as the air take more time to heat up by the lower velocity there. Did you see an advantage which can confute my calculation?

Regarding the TB diameter, it depends on your engine setup. I didn't see any advantage of going over 72 mm of ID with an RRC on a bolts on engine. As long as the parts down the road can't flow more air, it is just a disadvantage in terms of load control of the engine for the user. Huge throttle bodies make the load coming bouncy of the seat. My 74 mm ID TB produces 90 % of WOT MAP at around 20 % opening. For a race car this might be ok if you don't corner like Schuhmacher, he uses a very smooth control to keep the chassis slightly oversteering. For a DD this is not something you can call comfortable and precisely controllable.
:twocents:
 

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I am getting ready to install my 70mm TB that is tapered to 74mm on a ported n shaped RBC. the intake pipe consists of a 74mm ID piece, then a 74mm ID x 3.325" ID concentric reducer that is almost 5" long to 3.5" piping (3.325" ID). Finishing to a 3.325" ID velocity stack. I am betting this intake design will create velocity and air speed. It is a ram air set up.

I bought a Speed Factory tucked radiator that is 9.5" tall. I will have huge feeding ducts from the front grill to the bottom of the air box. I am using a 2017 Civic Type R hood vent scoop fabricated into a hood scoop to feed the topside of the filter box.

what I am betting on as vehicle speed increases, real world power gains will take place from the air velocity into the filter box.
 

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Beside that the misalignment of the flow due to the thickness of the gasket - it's wall has no 15° angle like the port has - flow is always off an alignment. Beside that there is still no evidence those insulation gaskets can improve knock margin distance or increase the density on WOT. My calculation of an inflow process shows for the ideal case of the IM has the same temperature as the air, the difference in density to the stock gasket is lower than 1 °C. This means, this would be no measurable effect on knock margin at WOT. On part load the story is different as the air take more time to heat up by the lower velocity there. Did you see an advantage which can confute my calculation?

Regarding the TB diameter, it depends on your engine setup. I didn't see any advantage of going over 72 mm of ID with an RRC on a bolts on engine. As long as the parts down the road can't flow more air, it is just a disadvantage in terms of load control of the engine for the user. Huge throttle bodies make the load coming bouncy of the seat. My 74 mm ID TB produces 90 % of WOT MAP at around 20 % opening. For a race car this might be ok if you don't corner like Schuhmacher, he uses a very smooth control to keep the chassis slightly oversteering. For a DD this is not something you can call comfortable and precisely controllable.
:twocents:
i was planning on cutting a matching angle on the thermal IMG to the port.

the misalignment I was referring to was the actual intake ports. they dont even come close to lining up to the cnc gasket. Some heads must not be equal. I know when I put the oem IM gasket the ports are still off horribly unlike my current PRB head I am using now on my engine.
 

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Arouse the DAMPFHAMMER!
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the misalignment I was referring to was the actual intake ports. they dont even come close to lining up to the cnc gasket. Some heads must not be equal. I know when I put the oem IM gasket the ports are still off horribly unlike my current PRB head I am using now on my engine.
Maybe we have a different understanding regarding the misalignment regarding an IM gasket. Could you draw a picture of it what you mean please?
 
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