7racer

I guess with this setup, the radiator no longer needs fans??? Or are they mounted somehow...just can't tell in your pictures.

SPOautos

Why V mount is better than a SMIC:



1. The SMIC air exposure is fixed by the duct. Even if you upgrade to an aftermarket bumper, the air going through the SMIC is the same. Your SMIC will not get any benefit of that. But ifyou use a v-mount, you can increase the air flow going through the intercooler to increase the efficiency.



2. There is no such thing as intake, intercooler, radiator fighting for air. The total amount of air going through all of them is fixed, determined by the frontal area of the bumper. Even if you have a cold air box, SMIC, and regular stock mount radiator, the total amount of air going through them is still fixed. The benefit of V mount is that you will be able to distribute the air flow effectively by using ducts. You can never do that with a SMIC.



3. It simply works better with a vented hood which is getting popular now than the SMIC.



There is a few long threads on the rx7forum on this. I have explained in details there. You can go there and check it out. Thank you.



Chuck [/quote]

1. You are correct the smic air flow is fixed by the duct and its also "tuned" for the size IC. The IC core cant flow its size in air because the core is about 70% metal which doesnt flow. It only flows about 30% of its size which is why my duct was 30% the size of the core.



2. Why wouldnt you be able to distribute the airflow with a SMIC set up? Even the stock system distributes the airflow. The way I see it is that the V mount doesnt distribute without ducts, which is what I was saying in the beginning....which was based on me not seeing any ducts. Now that you say you are including duct, I agree its going to be a good setup. Without the ducts though I dont think its all that great.



As for your test, I dont know all the conditions so its hard for me to comment. How long were you driving? How fast were you going? Was the temp 80C cause it just wasnt enought time? Where did you take your air temps at? What rpms were you running.



I dont expect you to answer those, I'm just pointing out that there are a lot of factors. Mine also shows ambient readings under the right conditions, right conditions being the key word there haha



What made you decide on the Vmount instead of something like a liquid/air set up? I'm thinking about a liq/air set up now.



And yea, I've seen the thread on the other forum already.



STEPHEN [/quote]

Hello Stephen:



Here are the answers to your question:



1. You can't caculate the air flowing through the intercooler like that because you are not taking pressure into consideration. Even with the same area of inlet area, with a higher pressure, you can get more air through the core. But how much air going into the channel is already pre-dertermined by the size of the inlet. To think of it in an easier way, if you can increase the size of the inlet and still getting the temp down, you know the size of the duct is not big enough.



2. You definitely can distribute the air with the SMIC but how much you can distribute is fixed. Let's say if you get a bumper with larger mouth, can you get more air flowing through the intercooer? You can't because the size of the intercooler duct is fixed. You will be able to get more air flowing through the intercooler on the v mount even without a duct because right now there is more air flowing into them. Even without a divider, the intercooler will still get more air flow than your SMIC because how small your intercooler duct is. The key is the size of the inlet. On the v mount, the size of inlet is the openig of the mouth. On the SMIC, the size of the inlet is only about 3"x10" at most.



3. When I did the initial test, the car has been driven for 50 miles. The car is fully warmed up. The air temp is taken at the manifold read by power fc. I am accelerating from 50-100 mph running 14 psi on T51R kai so about 4000 to 8000 rpm on my automatic in 2nd gear.



4. I don't know how you can do a air/liquid intercooler on the street driven FD. You either need a ice tank or another heat exchanger like the radiator. For the ice tank, you can pretty much only use it on the drag car. For the exchanger, we don't really have another place to put it do we?



The key point is the inlet size of the duct or air channel. Thank you.



Chuck Huang [/quote]

The duct inlet is also under pressure just like the core of a fm or vm IC would be. Its still getting the same amount of pressure and its the same size as the holes in the core. So whats the difference? You have the same amount of pass thru space and they are under the same pressure...they should be able to flow the same amt of air thru them. The size of your inlet for the IC is not the opening of the bumper, that the size of the inlet for you IC, radiator, and intake. They are sharing that air. Like I said with ducts I think its a nice set up....all my original comments were based on it not having ducts because at the time it didnt have any ducts.



The best way to run the liq/air is to have a ice bucket AND a heat exchanger thats about the size of a oil cooler. I'm going to mount mine where the R1 cooler goes (I dont have a R1 so its empty now).



STEPHEN

rotaryextreme

Why V mount is better than a SMIC:



1. The SMIC air exposure is fixed by the duct. Even if you upgrade to an aftermarket bumper, the air going through the SMIC is the same. Your SMIC will not get any benefit of that. But ifyou use a v-mount, you can increase the air flow going through the intercooler to increase the efficiency.



2. There is no such thing as intake, intercooler, radiator fighting for air. The total amount of air going through all of them is fixed, determined by the frontal area of the bumper. Even if you have a cold air box, SMIC, and regular stock mount radiator, the total amount of air going through them is still fixed. The benefit of V mount is that you will be able to distribute the air flow effectively by using ducts. You can never do that with a SMIC.



3. It simply works better with a vented hood which is getting popular now than the SMIC.



There is a few long threads on the rx7forum on this. I have explained in details there. You can go there and check it out. Thank you.



Chuck [/quote]

1. You are correct the smic air flow is fixed by the duct and its also "tuned" for the size IC. The IC core cant flow its size in air because the core is about 70% metal which doesnt flow. It only flows about 30% of its size which is why my duct was 30% the size of the core.



2. Why wouldnt you be able to distribute the airflow with a SMIC set up? Even the stock system distributes the airflow. The way I see it is that the V mount doesnt distribute without ducts, which is what I was saying in the beginning....which was based on me not seeing any ducts. Now that you say you are including duct, I agree its going to be a good setup. Without the ducts though I dont think its all that great.



As for your test, I dont know all the conditions so its hard for me to comment. How long were you driving? How fast were you going? Was the temp 80C cause it just wasnt enought time? Where did you take your air temps at? What rpms were you running.



I dont expect you to answer those, I'm just pointing out that there are a lot of factors. Mine also shows ambient readings under the right conditions, right conditions being the key word there haha



What made you decide on the Vmount instead of something like a liquid/air set up? I'm thinking about a liq/air set up now.



And yea, I've seen the thread on the other forum already.



STEPHEN [/quote]

Hello Stephen:



Here are the answers to your question:



1. You can't caculate the air flowing through the intercooler like that because you are not taking pressure into consideration. Even with the same area of inlet area, with a higher pressure, you can get more air through the core. But how much air going into the channel is already pre-dertermined by the size of the inlet. To think of it in an easier way, if you can increase the size of the inlet and still getting the temp down, you know the size of the duct is not big enough.



2. You definitely can distribute the air with the SMIC but how much you can distribute is fixed. Let's say if you get a bumper with larger mouth, can you get more air flowing through the intercooer? You can't because the size of the intercooler duct is fixed. You will be able to get more air flowing through the intercooler on the v mount even without a duct because right now there is more air flowing into them. Even without a divider, the intercooler will still get more air flow than your SMIC because how small your intercooler duct is. The key is the size of the inlet. On the v mount, the size of inlet is the openig of the mouth. On the SMIC, the size of the inlet is only about 3"x10" at most.



3. When I did the initial test, the car has been driven for 50 miles. The car is fully warmed up. The air temp is taken at the manifold read by power fc. I am accelerating from 50-100 mph running 14 psi on T51R kai so about 4000 to 8000 rpm on my automatic in 2nd gear.



4. I don't know how you can do a air/liquid intercooler on the street driven FD. You either need a ice tank or another heat exchanger like the radiator. For the ice tank, you can pretty much only use it on the drag car. For the exchanger, we don't really have another place to put it do we?



The key point is the inlet size of the duct or air channel. Thank you.



Chuck Huang [/quote]

The duct inlet is also under pressure just like the core of a fm or vm IC would be. Its still getting the same amount of pressure and its the same size as the holes in the core. So whats the difference? You have the same amount of pass thru space and they are under the same pressure...they should be able to flow the same amt of air thru them. The size of your inlet for the IC is not the opening of the bumper, that the size of the inlet for you IC, radiator, and intake. They are sharing that air. Like I said with ducts I think its a nice set up....all my original comments were based on it not having ducts because at the time it didnt have any ducts.



The best way to run the liq/air is to have a ice bucket AND a heat exchanger thats about the size of a oil cooler. I'm going to mount mine where the R1 cooler goes (I dont have a R1 so its empty now).



STEPHEN [/quote]

Stephen:



I am sorry that right now I am so overwhelmed, I don't have time to do all the math calculation at this time but I will get back to you on that and also the theory.



Just look at it from the simplest way. If you can prove that by increasing the size of the inlet of the intercooler duct, you are not going to increase the effciency, you know the size of the duct is big enough and vice versa. If you read my thread on the rx7forum.com, Kevin Wyum from ASP can't argue with this and he is the one who makes the M2 SMIC and he has sold about 200 of them. He didnt' agree with me but his silence tells you something.



About the air/cool IC, yes, I can have it done too but it will cost a lot more. You need to also have a water pump. It's just money you are talking about. Everything is possible as long as you have $$$. =)



Chuck Huang

SPOautos

I agree, money is the key lol. Well, dont kill yourself trying to do calculations, its not that big a deal. I agree that the duct needs to be "sized" for the core. I believe this is the main reason the M2 large doesnt do much better than the M2 med. They have the same amount of airflow to draw heat out of the core. However with a new front bumper you can make a huge duct. I know with my Apexi bumper I could make my duct go all the way across the opening instead of the standard 10" or so.



Anyway, I'm glad to see a vendor thats coming out with new products, I think all the old school 3rd gen products are getting "stale" and I'm ready to see some new products on the market. This is one reason I went with my BNR twins, just cause they would get me the pump gas power I want and no one else has them. Also, they have the sleeper appeal to them that I like. Nothing like traping 125+ on pump gas with "stock" twins haha



STEPHEN

RX73rdgen

How come RX7s have such problems with cooling with an FMIC.



I've had two turbo cars before my RX7 that had a factory FMIC and no cooling problems.



Perhaps it's due to the rather small front inlet area of the RX7? Or because rotaries need more cooling?



-John

SPOautos

No its because the the surface of the FMIC is about 70% metal so its like taking a piece of sheet metal and covering 70% of your bumper inlet. You loose a lot of airflow.



STEPHEN

RX73rdgen

Right... I understand that. I guess factory FMIC cars just must be designed with more frontal intake area then and the RX7's is not adequate (when covered with an intercooler)?



-John

vspecpgt

spoautos? i think i understand what you are saying about the whole airflow thing, if the intercooler has bigger holes than the radiator than more of the air would go through the intercooler right? at least that is what i was thinking, but even without ducting i think it would get plenty, cause a lot of air is still going to get rammed in there... also about the ducting... couldn't you use just one small horizantal peice in the mouth of the bumper? therefore splitting the air into the intercooler and radiator evenly? something like this: (hope it comes out in the post correctly)



bumper mouth top

intercooler

---------- horizantal duct

radiator

bumper mouth bottom

SPOautos

There arent many cars with a factory front mount, the only ones I've seen they are actually positioned behind the radiator not infront of it....granted I havent seen every factory car in the world. If they do mount the IC infront of the rad from the factory they probably have a duct going to the radiator to draw air to it rather than it having to rely on the air thats passing thru the IC.



STEPHEN

SPOautos

Yea, thats basically what I was saying in the beginning. Since it didnt have any form of duct or dividers to channel the air. BUT Chuck made some type of duct work for his V mount so it should work like a champ.



STEPHEN