Ported IM?

[Zitrosounds]

All modern variable cam timing cars use that for EGR nowadays.




I don't understand this mentality that because the OEM spent all this R&D on a product that it must be perfect. If that were the case there wouldn't be an aftermarket. People have been finding all kinds of ways to improve the factory stuff especially since the OEM didn't design these components purely for maximum performance. They had so many other considerations that those R&D dollars and hours were spent on.




Not just them, the Coyote was a big hit for minor porting mods even though the results were relatively minor. The factory plastic intakes are super easy to remove and do some minor port matching.

I am not saying that an after market peace wont yield results. What I am saying is the the GT350 manifold to include the heads are very much optimized and matched. therefore modifying the OEM piece would yield minimal results. Perfect example is the CJ IM. The biggest difference and gain are most certainly in the runners and throttle body and yet it only eeks out the 350 mani.

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[Mjc1241]

Just talked to Slawko Racing who actually does port 5.2 heads as well as a local guy here in GA that is pretty damn good and has done a few and both stated that the heads ports can be cleaned up some and will yield some results. Slawko Racing stated that best possible scenario would be to port match the intake to the heads for optimal results. The tricky part, per Slawko is to retain the stock compression. It can be done. Unless something changes, I will find out at some point in the next 12-16 months. I want to do some basic weight reduction and suspension upgrades first.

 

[Zitrosounds]

Just talked to Slawko Racing who actually does port 5.2 heads as well as a local guy here in GA that is pretty damn good and has done a few and both stated that the heads ports can be cleaned up some and will yield some results. Slawko Racing stated that best possible scenario would be to port match the intake to the heads for optimal results. The tricky part, per Slawko is to retain the stock compression. It can be done. Unless something changes, I will find out at some point in the next 12-16 months. I want to do some basic weight reduction and suspension upgrades first.

Sounds like big money work for "some results."

 

[UAmach1]

Sounds like big money work for "some results."

Agreed. It may be more worth it if you go FI, or have heads/cams and have it all apart anyway and want it matched. Maybe more worth it for shop cars or the more hardcore/consistent racers that can actually show better times off only the small gains it would give. Doesn't seem worth it to the average driver.

 

[stanglife]

I found the best new intake:

 

[Mjc1241]

Cost is relative to what your goal is. Price out a whipple or ProCharger kit and new clutch, because you will need it, and the cost of install with custom tune and let me know. My intent is not to have the highest horsepower. I can go my route for max half of the cost of going FI. If I wanted an FI car, I would have bought a Roush S550, ZL1 or C7 Z06.

 

[stanglife]

Cost is relative to what your goal is. Price out a whipple or ProCharger kit and new clutch, because you will need it, and the cost of install with custom tune and let me know. My intent is not to have the highest horsepower. I can go my route for max half of the cost of going FI. If I wanted an FI car, I would have bought a Roush S550, ZL1 or C7 Z06.

I get it. I appreciate a solid NA car. I have the R and I also have an RS4, arguably one of the best NA sedans ever sold with a manual (I'm biased). My last fun car was a Boss 302 powered 93 coupe.

I'm happy with my R - BUT, I think I mentioned somewhere, I'm starting to get accustomed to the power it makes and it's starting to not feel fast ;) Does this happen to anyone else?

 

[nastang87xx]

Overlap is handled by the Ti-VCT (Twin Independent Variable Camshaft Timing). Both the intake and exhaust cams are individually timing controlled, thus overlap can (and most likely is) being optimized, I would think.

Correct. Install a set of Stage 3 cams on a Coyote for instance. Once tuned, they don't chop at all unlike say a huge overlap duration LS motor that's just lumber jackin' like a motha fawka.

I still like the idea of cams until I'm proven otherwise of course. Leave the intake manifold alone. Bigger throttle body to help with low end (are you listening Accufab?). Individual primary short tube headers (I'd prefer to keep the cats to reduce sound dB's. Some of us actually like to hit the race track at times that aren't a special unrestricted dB event once every year).

I truly believe 590 - 600 HP is lurking in this engine with a bigger intake, longer duration cams, 4 - 1 short tube headers, and a safe calibration. And without raising the 8250 redline.

 

[nastang87xx]

I'm happy with my R - BUT, I think I mentioned somewhere, I'm starting to get accustomed to the power it makes and it's starting to not feel fast ;) Does this happen to anyone else?

Happened to me. Not that it's not fun, you just get used to anything really. Milwaukee Mile infield road course and Road America has taught me a LOT...

 

[nastang87xx]

I found the best new intake:

Well...you're not wrong per say haha. I just don't want to add another 150lbs to the car.

 

[chitlins37]

I'm happy with my R - BUT, I think I mentioned somewhere, I'm starting to get accustomed to the power it makes and it's starting to not feel fast ;) Does this happen to anyone else?

I am not there yet but I can absolutely see where you’re coming from. No chance I’m making any performance mods before warranties are up yet I perk up and take note(s) everytime I see a thread like this or the fathouse fabrication type builds. Even though I can’t really run this beast on the street without risking a massive ticket I’m still in love with the idea of making it faster :headbonk:

 

[Zombo]

Bigger throttle body to help with low end.

I'm no ICE engineer, but it has always been my understanding that increasing the TB size will improve top end performance at the detriment of low end. No?

Low end torque is improved by increasing flow velocity of the intake charge, which is accomplished by reducing the cross sectional area of the flow path. Once the flow rate increases with increased RPM, the reduced area starts to become a restriction, which reduces flow. Hence, many engines now use a 2 stage intake manifold (long, small area runners for low end torque and short, larger area runners for the high end).

Perfect illustration of this is my brother's '71 Plymouth GTX with a 440 6 barrel. The center carb, which I believe is a 350 CFM is normally operating (for low end torque), and the 2 outer carbs (600 CFM each) operate only when called upon for high end power. My CFM numbers may be a bit off, but you get the point.

It is for this reason, I'm skeptical about messing with anything in the intake tract without doing analysis and testing. You may do something that improves things a bit at the top end, but kills the low end.

But, as I stated, I'm not an ICE engineer, and am certainly open to learning...

 

[Mjc1241]

I called Slawko Racing myself yesterday to inquire about the 5.2 ported heads. If anyone has questions, give them a call.

 

[TheDeadCow]

I'm no ICE engineer, but it has always been my understanding that increasing the TB size will improve top end performance at the detriment of low end. No?

Low end torque is improved by increasing flow velocity of the intake charge, which is accomplished by reducing the cross sectional area of the flow path. Once the flow rate increases with increased RPM, the reduced area starts to become a restriction, which reduces flow. Hence, many engines now use a 2 stage intake manifold (long, small area runners for low end torque and short, larger area runners for the high end).

Perfect illustration of this is my brother's '71 Plymouth GTX with a 440 6 barrel. The center carb, which I believe is a 350 CFM is normally operating (for low end torque), and the 2 outer carbs (600 CFM each) operate only when called upon for high end power. My CFM numbers may be a bit off, but you get the point.

It is for this reason, I'm skeptical about messing with anything in the intake tract without doing analysis and testing. You may do something that improves things a bit at the top end, but kills the low end.

But, as I stated, I'm not an ICE engineer, and am certainly open to learning...

I agree, this may be a lead in to why Ferrari chose to go with dual TB's on their FPC V8's.

 

[Mjc1241]

FYI. CorteX Racing has confirmed via my email outreach this morning what a previous member stated. They are helping to develop an intake manifold for targeted availability in the summer of 2018. I asked a few other questions and will report back if they are able to respond in kind. Trying to ask questions without prying too much as they may only be able to answer in general terms at this time.

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