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2G EVO III (3) Intake Manifold w/ stock Ports Vs Curt Brown Ported Evo III Comparison??

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95eclipser

15+ Year Contributor
2,003
309
Feb 3, 2006
Manassas, Virginia
EVO III (3) Intake Manifold w/ stock Ports Vs Curt Brown Ported Evo III.

Hey Guys.

So, recently I decide I wanted to switch out my older Magnus SMIM for a Evo 3 Intake manifold and continue to use my 1G Tb. The reason I decided on this was for Spool and Torque improvements, along with the fact that the EVO 3 shows it can hold its own against these other manifolds up to a certain RPM. (8200~ishh)

What I am looking for, because i haven't been able to find any info, are real dyno graphs that shows the evo 3 before and after the port work is done? Although the port work is cheap enough I may just do it anyways but since i haven't seen any results. I'm wondering if its not really needed?

Does anyone have any feedback on this? If so please explain what your setup is, and if you have a graph that would be great also!

If anything i was thinking of just opening up the throat on the EVO 3 inlet, and leaving the rest stock.

Edit.
my setup is as follows.
2.0
272 kelford cams
1G TB
Magnus SMIM
PTE-6262

Thanks,
 
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Sorry I don't have any real technical info, but my sense tells me that since people are switching over to the evo 3 intake manis because of the reasons aforementioned, I feel like it'd be wise to keep it the way it is and save some money. Taking a quote from a pretty knowledgeable member here:

The Evo 3 intake/2g head is a great street combo. The smaller ports of the 2g head keep the velocity up, aiding lower end torque, yet still flow enough to be wound tight. The Evo3 intake has a bigger plenum and shorter runners than a 2g intake. This will allow it to make power higher up in the rpm band. It's a nice comprimise between the 6500rpm cuttoff of a stocker and the lack of low end a SMIM would typically have.

Now, I figure messing with it any bit as far as porting goes would definitely increase flow potential but it would also shift the power band higher (very slightly) while losing low end. This is just a guess on my end. If opening up the inlet to match the outlet of the 1g tb, then buy all means go for it. But if it's already well matched, I would suggest don't even bother. I run a 1g nt tb and an evo 3 intake. The throttle body bore is 60mm and the evo 3 intake mani has a 60mm inlet so they match up perfectly. Your 1g tb is also 60 mm. So, untouched, your tb and intake mani will match up perfectly. Also, the outlet ports the evo 3 intake should also perfectly match that of the inlet ports to the 2g head. Understand what I'm getting at here?
 
I see your point, and I appreciate the response man. All I ever see on the CB stuff was that it "puts in work" or something about it being "awesome", but I like to see a little more proof then that. This is the internet after all LOL.

I'm sure it works and works well. I just was hoping for dyno results.

Might as well just leave it alone and call it a day. If anyone else has anymore input please post.
 
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Yeah LOL not a very scientific form of marketing. I've talked to curt Brown and he knows his stuff, but when getting a plan to work on my head, he gave me suggestions for all out power. And sometimes we don't want just all out power, we want streetable power.

Maybe give him a call and have a word with him? He's a very cool guy and will answer what you need. Idk if he has analytical data for you but it's worth a shot.
 
I shouldn't post this because it's going to cause a big shit storm of pissing off all the fanbois. And then a bunch of arm chair quaterback's will tell me my test is flawed, blah blah blah.

I have long said/thought that an EvoIII intake bolted to a 6 bolt head would possibly be a great combo. However, everyone wears blinders and complains that the port mismatch will cause turbulence, it'll never work, it'll suck, blah blah blah. Here's the point everyone misses. The actual port difference between a 1g and 2g head is a triangle shape about .4" tall 1.25" long, it's not much and has little effect on flow. If you have an open mind and think critically about it, you realize it may not be such a bad thing.

So anyway, I finally got around to modifying an evo intake in late 2016 and ran it for a while, huge bottom end gain over my old intake. It was made from a stock 6 bolt with the runners chopped off in the middle and a new plenum welded on. I wasn't convinced the EvoIII was getting it done on the top end. So I replaced it with a giant port huge plenum intake, thinking I picked up big power.

Here's a pair of dyno tests with nothing changed but bolting on an Stock port EvoIII intake vs a stock 1g 6 bolt intake. The evo intake was only cleaned up I removed casting flash inside the plenum, and runners, but I did not resize the runners at all. I welded up the flange to cover the 6 bolt port and machined it flat. The combo is a 2.0l 8.5:1, Kelford 272 cams, stock port 6 bolt head, and a GT3788R turbo on E85. This was at 20psi.
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Here's what to take away, a stock 6 bolt setup kills a EvoIII intake on the bottom. Those long runners are hard to beat for torque production. So these guys with a 16g, and a 6 bolt head/intake ditching it for a 2g/EvoIII are not gaining shit. Really if your If your on a smaller turbo 16g/20g/50trim. I don't think there is any reason to leave a stock intake. I havn't tested a 2g intake on this, but I can't imagine it would be terribly different, probably a bit better bottom and less top. Not because of the 2g head port, but because of the length of the 2g intake being smaller area. This does much more for improving velocity than the small difference between a 1g and 2g head. And I'll say it here, yes I think a 6 bolt head/intake is an upgrade to a 2g. Any gains a 2g setup is going to have will be at an RPM so low it will be unusable anyway, unless your on a T2small or a 14b.

Think about your powerband, if you shift at 7000 the power is equal, but on the 1/2 you fall back to 3800 - down there a 6bolt setup might be 50-75+hp up on a EvoIII. Yes I understand that this dyno sheet was with a GT37, but I also understand that a smaller turbo or cams is going to shift both curves to the left.

If your on a more meduim size turbo like a 35R, HX40, 6262, the EvoIII is a better match, as your going to reving out to 8500-9000+ So when you shift 1/2 at 9500, you fall back to 5100, right where the torque is coming up. I don't think I would look at a big sheet metal until like 280+ cams and a 6766 or 40R or bigger, and revving 10k+
 
I see your point, and I appreciate the response man. All I ever see on the CB stuff was that it "puts in work" or something about it being "awesome", but I like to see a little more proof then that. This is the internet after all LOL.

I'm sure it works and works well. I just was hoping for dyno results.

Might as well just leave it alone and call it a day. If anyone else has anymore input please post.

Clean up casting flash and run it. I promise you won't be disappointed.
 
I shouldn't post this because it's going to cause a big sh** storm of pissing off all the fanbois. And then a bunch of arm chair quaterback's will tell me my test is flawed, blah blah blah.

I have long said/thought that an EvoIII intake bolted to a 6 bolt head would possibly be a great combo. However, everyone wears blinders and complains that the port mismatch will cause turbulence, it'll never work, it'll suck, blah blah blah. Here's the point everyone misses. The actual port difference between a 1g and 2g head is a triangle shape about .4" tall 1.25" long, it's not much and has little effect on flow. If you have an open mind and think critically about it, you realize it may not be such a bad thing.

So anyway, I finally got around to modifying an evo intake in late 2016 and ran it for a while, huge bottom end gain over my old intake. It was made from a stock 6 bolt with the runners chopped off in the middle and a new plenum welded on. I wasn't convinced the EvoIII was getting it done on the top end. So I replaced it with a giant port huge plenum intake, thinking I picked up big power.

Here's a pair of dyno tests with nothing changed but bolting on an Stock port EvoIII intake vs a stock 1g 6 bolt intake. The evo intake was only cleaned up I removed casting flash inside the plenum, and runners, but I did not resize the runners at all. I welded up the flange to cover the 6 bolt port and machined it flat. The combo is a 2.0l 8.5:1, Kelford 272 cams, stock port 6 bolt head, and a GT3788R turbo on E85. This was at 20psi.
You must be logged in to view this image or video.

Here's what to take away, a stock 6 bolt setup kills a EvoIII intake on the bottom. Those long runners are hard to beat for torque production. So these guys with a 16g, and a 6 bolt head/intake ditching it for a 2g/EvoIII are not gaining sh**. Really if your If your on a smaller turbo 16g/20g/50trim. I don't think there is any reason to leave a stock intake. I havn't tested a 2g intake on this, but I can't imagine it would be terribly different, probably a bit better bottom and less top. Not because of the 2g head port, but because of the length of the 2g intake being smaller area. This does much more for improving velocity than the small difference between a 1g and 2g head. And I'll say it here, yes I think a 6 bolt head/intake is an upgrade to a 2g. Any gains a 2g setup is going to have will be at an RPM so low it will be unusable anyway, unless your on a T2small or a 14b.

Think about your powerband, if you shift at 7000 the power is equal, but on the 1/2 you fall back to 3800 - down there a 6bolt setup might be 50-75+hp up on a EvoIII. Yes I understand that this dyno sheet was with a GT37, but I also understand that a smaller turbo or cams is going to shift both curves to the left.

If your on a more meduim size turbo like a 35R, HX40, 6262, the EvoIII is a better match, as your going to reving out to 8500-9000+ So when you shift 1/2 at 9500, you fall back to 5100, right where the torque is coming up. I don't think I would look at a big sheet metal until like 280+ cams and a 6766 or 40R or bigger, and revving 10k+

bastard, I usually like what you do, but this one is a stretch.
You're showing what an Evo III intake does on a stock 2g with a small turbo, by posting dyno plots of a car with a 1g head with a big turbo? I appreciate your insight, but there is no way this is remotely comparable. Test the 2g intake back-to-back, and it would have some validity.

OP, just look up Evo 123 builds with ported intakes. There has to be someone out there who has done this.
 
Your more than welcome to go ahead and spend the money to do the testing on your own.

I understand that it's apples and oranges, BUT the trends do not lie. In my example at 4600 when the pull starts they have basically identical boost. Actually the EvoIII has more, yet the 6 bolt intake has 40ft*lbs more torque. Here's the key points, the intake manifold does not know what turbo is attached to the other side of the cylinder. The runner length and area do not know what turbo is attached. They don't even really know what cam profile is used. All they know is a longer runner is going to have a lot more "inertia" than a shorter runner, because there is more moving mass contained.

The fact is a longer runner is going to produce more bottom end as it will have more inertia to keep pushing air in after bdc. And yes a smaller area runner should have more bottom than a similar length large area runner. You could probably get a shorter small area runner to perform like a longer large area runner. Remember Inertia or momentum is mass * velocity, mass = length*area*density, and velocity is mass flow/area. But in this case of a 1g vs and EvoIII intake the evo 3 is not a design for low rpm, but it is a great compromise between a stock intake and the super short runner big plenum race intakes.

The trends do not change because of a different cam or turbo. A stock 1g intake isn't magically going to be a 10000RPM intake because you put a 42R on a car, niether is a Forrester/BJ's/MAGNUS/JMF going to be a 3500rpm intake because it's on a T25.

If I had the time and money I'd gladly do my testing again with a 16g, and I'm confident you'd see the results that I suggest. A 6bolt head/intake would be better than a Evo3/2g, and probably close to a 2g/2g.

As for a 6bolt head being that much different, they are not. The welding rod represents the difference. Yes, I could see there possibly being peak flow issues, but that little area change will do little to the air speed of the moving mass. From my testing it doesn't affect a thing.
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It's a good idea to keep in mind what Mitsubishi was going for when they tuned the Evo3. They weren't building a top-end monster. Where the 4G63 WRC cars, the Evolution 3 in particular, outclassed their competitors was in mid-range torque, which in comparison is much more important on a rally stage than a drag-strip. Thus it follows that the Evo3 intake and exhaust manifolds were modeled with mid-range in mind, and this has been backed up by dyno results on DSMs--a loss of low end over the stock manifold, with more in the mid-range, but less in the top-end compared with a Magnus or SMIM.
 
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RVR intake ported 63mm to match my 1g N/A throttle body 7 bolt built with "G" cams (yes the G cams 262/260 G cams... i actually found a set), evoIII 16g 91oct. revlimit 85k. #SENDIT

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RVR intake ported 63mm to match my 1g N/A throttle body 7 bolt built with "G" cams (yes the G cams 262/260 G cams... i actually found a set), evoIII 16g 91oct. revlimit 85k. #SENDIT

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I like the shaved red valve cover--I was thinking of doing similar until a found an Evo3 valve cover. What'd you do for the coil mounts? They're 1g style?
 
I love finding bastarddsm s posts. Always great reads and the fact he takes the time to test combos and post is great, that takes a lot of time and money that he wouldn't have to share.
His numbers don't lie and it makes sense a smaller turbo and cams will shift the lower end to the left but otherwise the power delivery would look the same albeit lower.

The one point that I see that may be different though and I'm playing devils advocate here is the fact that a smaller turbo and cams will increase airflow at lower rpm just for the fact of it's ability to get lit faster. I'm not sure if or any help that would be or if it would in fact change the onset of torque.
 
What I have taken from the post. And please correct me if I am wrong...

But the Evo 3 manifold with a (272 cam setup and similar turbo 6262-GT35 ETC) Allows me to gain back some low-mid range power/tq, while still allowing me to make decent power up top and not lose anything in my 1-2 shift etc, that my current magnus may be doing.. My whole point in this is to improve my power throughout my entire RPM band and not just have a highway monster.
 
RVR intake ported 63mm to match my 1g N/A throttle body 7 bolt built with "G" cams (yes the G cams 262/260 G cams... i actually found a set), evoIII 16g 91oct. revlimit 85k. #SENDIT

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I was under the impression that the 1g nt tb is NOT 63mm. It is 63mm at the lip of the inlet of the tb and tapers down to 60.3mm. So I don't know if you really mactched it. I have a 1g nt tb and it is actually matched up to my evo 3 without having to port it. Really, there's no advantage to running an nt tb over a 1g turbo tb other than losing a gasket, which is why I got mine.
 
I've ran the rvr 2g combo for a long time I have no money in it so that was a win. With a 20g and gsc s2 cams it really didn't feel different. But moving from your Magnus to that your going to notice an improvement for sure just from the fact that the runners will promote lower end power for sure.
 
I was under the impression that the 1g nt tb is NOT 63mm. It is 63mm at the lip of the inlet of the tb and tapers down to 60.3mm. So I don't know if you really mactched it. I have a 1g nt tb and it is actually matched up to my evo 3 without having to port it. Really, there's no advantage to running an nt tb over a 1g turbo tb other than losing a gasket, which is why I got mine.

Here is more information on the difference of the throttle bodies. The 1g NT throttle body gives the most flow.

http://www.throttlebodys.com/1GNT_TBs.htm
 
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Here is more information on the difference of the throttle bodies. The 1g NT throttle body gives the most flow.

http://www.throttlebodys.com/1GNT_TBs.htm

I've had Steve Monroe work on my throttle body and we've exchanged a lot of emails back and forth. He's a very cool guy. That doesn't give info on the differences though. He even stated to me that:
"Well the taper and polish mod does not increase the minimum diameter of 60mm at the throttle plate. It's still 60mm there, same as factory. The T&P thins the square edged lip which smooths out the air flow. Less turbulence, less friction b/c of the polished front section."

So, stock, the nt tb is NOT 63mm fully.

That good info listed there, but at that price I would just buy a S90 TB and open the throat on the evo 3 to accept the 70mm. Call it a day.
Yeah, I didn't go with the S90 because I've read of a lot of people having issues with them. I also like the oem look. And lastly, I don't ever see myself needing that large of a size tb. These oem throttle bodies, to me, seem to be much more reliable.
 
Your more than welcome to go ahead and spend the money to do the testing on your own.

I understand that it's apples and oranges, BUT the trends do not lie. In my example at 4600 when the pull starts they have basically identical boost. Actually the EvoIII has more, yet the 6 bolt intake has 40ft*lbs more torque. Here's the key points, the intake manifold does not know what turbo is attached to the other side of the cylinder. The runner length and area do not know what turbo is attached. They don't even really know what cam profile is used. All they know is a longer runner is going to have a lot more "inertia" than a shorter runner, because there is more moving mass contained.

The fact is a longer runner is going to produce more bottom end as it will have more inertia to keep pushing air in after bdc. And yes a smaller area runner should have more bottom than a similar length large area runner. You could probably get a shorter small area runner to perform like a longer large area runner. Remember Inertia or momentum is mass * velocity, mass = length*area*density, and velocity is mass flow/area. But in this case of a 1g vs and EvoIII intake the evo 3 is not a design for low rpm, but it is a great compromise between a stock intake and the super short runner big plenum race intakes.

The trends do not change because of a different cam or turbo. A stock 1g intake isn't magically going to be a 10000RPM intake because you put a 42R on a car, niether is a Forrester/BJ's/MAGNUS/JMF going to be a 3500rpm intake because it's on a T25.

If I had the time and money I'd gladly do my testing again with a 16g, and I'm confident you'd see the results that I suggest. A 6bolt head/intake would be better than a Evo3/2g, and probably close to a 2g/2g.

As for a 6bolt head being that much different, they are not. The welding rod represents the difference. Yes, I could see there possibly being peak flow issues, but that little area change will do little to the air speed of the moving mass. From my testing it doesn't affect a thing.
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Not trying to change the direction of the thread but some very interesting points have been made here. I love the different way of thinking. I really wanted to run the E3 intake but I ended up picking up a ported 7bolt 1g head. Anyway it seemed like the 1g head wasn't a upgrade for the 2g because of port size and velocity etc. So to combat this I found the 97 Hyundai Sonata intake that has all the 1g attributes except for the port size and a larger plenum. I opened up just the ports with a slight taper to match the 1g ports. So basically 95% of the intake is the small port. Im not expecting crazy gains, if any, but I am hoping that the extra velocity helps with low end torque?? (Full weight auto AWD 2g). Sorry for the off topic subject but this gives me hope that my 1g head won't disappoint and I won't lose the "2g head design low end torque".
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I don't think I would have opened up the intake, but it probably won't matter. It would be neat to see a dyno test on those back to back, but being an auto your car will mask that some. I suppose a stall test on the 2 would tell us all you need to know.
 
If it helps at all, I'm currently building a 2g head/ported evo3 IM setup and i'll be sure to post logs back to back because I don't have plans to dyno the car any time soon.
 
Copy Cat :p:p:p
 
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