Intake manifold porting pictures... your thoughts please

[Bad Company]

The stiegiemier picture i posted was the work he does on road race/drag race cars. He does not recommend that port for street purposes. Everytime ive seen these ported, the screw bosses were always ground flush. I just assumed it was considered a standard when porting the manifold. Like you said, most likely minimal gains if any. But if its already on the bench.....

 

[Bad Company]

I was thinking about the big gun this winter for less pressure buildup/ parasitic loss. Has anyone noticed a bit less boost with the biggun/intake porting?

 

[Bad Company]

12345!

 

[Bad Company]

12345!

 

[madskills1969]

Bad company is this slawko work? Ports look pretty shinny..Last night I was not able to post any pictures for some reason

 

[Beercules]

You'll actually gain boost in the lower intake manifold where you'll be monitoring it. Why? Because you lowered the restrictions above the intercooler core to reduce boost there. So the pressure differential between to 2 areas changes. Lower boost under the SC with higher boost under the intercooler for the same volume of airflow entering the engine with no other mods. You'll reduce IAT2 due to the fact the pressure before the intercooler drops, so the air temps drop. 1 psi of boost exiting the supercharger adds 10*F to the air temperature. So if you have 100*F ambient air entering the SC inlet, it leaves the SC at 17 psi of boost that equals 270*F air entering the intercooler to be cooled to give you a IAT2 entering the engine. Now the restrictions of the intercooler stack the air up and you only net 14 psi of boost in the lower intake. That is a 3 psi differential. That is 3 psi of boost you lost that equals 30*F of heat you had to get rid of from the air to reduce the IAT2 readings at 14 psi of boost entering the engine.

Now if you can reduce the restriction of the intercooler to flow more air by volume, which a KB BIGGUN does. Than the same volume of air in our first example exiting at 17 psi of boost above the intercooler changes, because the pressure doesn't stack up in front of the intercooler. Lets say that the volume of air being moved to equal the 17/14 psi of boost in the example above is equal to the CFM flow rating of the Biggun intercooler.

So you are now no longer stacking air above the intercooler. You have an equal pressure differential. The pressure levels in the lower intake will go up and the pressures in the upper will go down. Where you monitor the pressure is in the lower, because this is what everybody monitors including the PCM for fueling requirements. So this pressure reading will go up in your recordings........not down. But the IAT2 will go down. Why? Because the intercooler now doesn't have to deal with the extra heat that the pressure differential was causing. IAT2 temps will drop. All things being equal they'll drop by roughly 15*F for the same airflow without having to worry about the intercooler and HE extracting that heat from the airflow entering the engine.

Ok, pressure sensor is UNDER the intercooler. Sounds like the biggun does reduce pressure restriction which will reduce sc power demand and send a little more to the wheels (efficiency=free power). Temps... via Boyles law, lower pressure means less heat energy (enthalpy) to remove.

For polishing...Google up boundary layer. Any deeper is theory as compared to what people are finding when they're actually doing it.

 

[Beercules]

Sorry, that's not right. Same enthalpy, less sensible heat (temperature).
Don't know how to edit with the new system.

 

[Beercules]

Sorry, that's not right. Same enthalpy, less sensible heat (temperature).

Sint know how to edit with the new system.

 

[Bad Company]

Bad company is this slawko work? Ports look pretty shinny..Last night I was not able to post any pictures for some reason

 

[serickson1]

There is one thing wrong with this intake manifold. once modified in this manner, the intake can never be used on a street driven car. Why? Because the bypass system has been eliminated. Without a bypass system the supercharger will not last 10 miles while the car is being driven at part throttle. The bypass system allows air to recirculate across the rotors of the SC to cool them. Essentially it let the air exiting the SC to blow through the intercooler and come back to the inlet of the SC. It is nothing but a big circle of airflow matching the CFM output of the SC versus what the engine isn't using. The SC is a constant air pump. If the engine isn't in boost, yet the SC is spinning fast enough to provide 15 psi of boost for that engine at that moment, the air has to bypass and wrap back into the inlet of the SC. To not allow this to happen causes the SC to run with an airflow deficit, which builds enough heat in the rotors for them to expand to the point of contact. Once the rotors touch each other, the SC needs to be repaired or replaced depending on how bad it is.

I have street driven my car over 7000 miles with a TVS, 3.4 Whipple, and 4.2 Kenne Bell, without any issues at part throttle....IAT's stay in the 120 range during the summer....that is a pic of my manifold that Steig. ported for me years ago....so I think you are a little off on your 10 mile comment....lol....

 

[Bad Company]

I have street driven my car over 7000 miles with a TVS, 3.4 Whipple, and 4.2 Kenne Bell, without any issues at part throttle....IAT's stay in the 120 range during the summer....that is a pic of my manifold that Steig. ported for me years ago....so I think you are a little off on your 10 mile comment....lol....

LOL

Well I can tell you that KB had to warranty repair my 3.6L when I drove it less than 10 miles before it started knocking after the bypass valve stuck shut. Without air circulation across the rotors for the volume of air the SC is capable of moving the rotor pack heats up. Otherwise why would Ford, VMP, Roush, Eaton, Whipple, Kenne Bell, Lyschom Edelbrock or anybody else have a bypass system on a street driven supercharger system?

If you have a KB 4.2 on it right now call Mike at KB tech support and ask him what he thinks of deleting the bypass system on one of their SCs and driving it on the street. I'll guarantee you he will tell you the exact same thing I've posted in this thread. And to either not street drive it or he won't honor any warranty that is left on it. Why do you think they've also had to come up with bypass valves for guys that install cams with low vacuum signals at idle? If they don't need them they wouldn't go to all the trouble and cost of installing them plus manufacture one specifically to somebody with aftermarket camshafts with low vacuum signals. Hell even your buddy markets one specifically for the TVS and his radical cam designs. Maybe you should call Michael at L & M to ask why he does it.

 

[jazz05]

i dont think you understand, this doesnt delete the bypass, instead it returns air from above the cooler instead of below it. For the guy running this on the street, did u notice any improvement in wot iat's? this is where the cobra jets running this claim improvement.

 

[blowbye]

Bad Company those pictures are pure machinists porn.

Thank you for expaining the pressure diffential, it was not someting i had ever considered. Im assuming that just the addition of the big gun intercooler would drop iat2 temps by 20 degress or so?

 

[serickson1]

Just giving you real world info BC.....I know your never wrong....lol...I don't know Michael personally and he is not my "buddy" but he is a good guy and builds one hell of a good motor...I see IAT 2's in the 120-130 range with a iced up trunk mount tank....I have been running the ported manifold the 3 yrs I've had the 4.2 so I don't have any before data logs to compare.

 

[Beercules]

Yep there shiny

I've had 3 of Tom Slawko's heads in my hand for a GT500.

Here is Tom's phone number to the answer to your questions. Either Tom will answer the phone himself or the young gentleman(which I forget his name at the moment) that does all of the Internet posting will. It has been a while since I've been up there, but I'm sure either of them will tell you exactly how they are finished in the ports. They may have refined the CNC programming again to get a better finish since the last time I was there, which was roughly 18 months ago. But I doubt they're doing a polished finish. Also the angle of those photos are looking straight down the port which doesn't allow you to see the detail of the finish texture

(610) 286-1822

Here is some interesting pictures of the work BES Racing Engines is now providing when doing CNC Port work. Its shiny too........real shiny on the wallet too LOL

Wouldn't you want it turbulent at this point anyway to mix the air/fuel?
Or maybe I'm just thinking incorrectly.

 

[Bad Company]

i dont think you understand, this doesnt delete the bypass, instead it returns air from above the cooler instead of below it. For the guy running this on the street, did u notice any improvement in wot iat's? this is where the cobra jets running this claim improvement.

Yes I'm thinking incorrectly.

It still is a very bad idea for a street driven car. Lets say you have a 100*F ambient temperature day when you decide to take the car out for a cruise. You decide to show off at some point in the cruise and stand in the throttle this build 20 psi of boost. Which with a KB 4.2 sitting on top of the motor is actually a very low boost number to generate. The air exiting the supercharger is now 300*F and going through the intercooler which has at the lowest possible temperature 100*F coolant running through it, because the HE can't drop the coolant temperature below ambient. Again this is the lowest possibility for the coolant temperature of the intercooler system to match ambient temperatures. So your cooling the IAT2 down to 130*F as they enter the engine........this is safe. Now once you've shown off enough you immediately shut the throttle. This creates a high vacuum and the bypass valve now open, yet the engine is still turning 6500 RPM. Which intern depending on the pulley combo is turning the SC fast. How fast well lets do a little math. The smallest lower is 7.5" with the biggest upper at 4" this equates to a drive ratio of 1.875. 6500 engine RPM x 1.875 = 12187.5 SC RPM. That is slow, but the negative is a big 4.2L SC. 4.2L x 12187.5 = 51,187.5 L per minute of airflow. That is 1807.7 CFM. That is a large amount of air that is now being directed right back to the rotor pack, instead of it being cooled by going through the intercooler and wrapping around through the bypass valve to come straight out of the exit of the SC right back into the entrance of the SC. Now how hot will the air be entering that big SC without going through the intercooler? Just before you took your foot off the throttle the air exiting the SC was 300*F. Talk about taking a risk of destroying a SC, to me that is a risk.

 

[Bad Company]

Bad Company those pictures are pure machinists porn.

Thank you for expaining the pressure diffential, it was not someting i had ever considered. Im assuming that just the addition of the big gun intercooler would drop iat2 temps by 20 degress or so?

Your welcome

 

[serickson1]

20 psi and 6500 rpm's on the street in a 1200hp car....lol....not happening BC...you have been out of the game to long...lol...I don't even THINK of stabbing the throttle our putting my car in boost on the street.....warm rotors are the least of your worries if your turning 6500 rpms on the street in my car...lol....but thanks for letting me know its a bad idea.

 

[Bad Company]

Just giving you real world info BC.....I know your never wrong....lol...I don't know Michael personally and he is not my "buddy" but he is a good guy and builds one hell of a good motor...I see IAT 2's in the 120-130 range with a iced up trunk mount tank....I have been running the ported manifold the 3 yrs I've had the 4.2 so I don't have any before data logs to compare.

Well your experience and mine dealing with him are two different things. You weren't there when I finally had enough of him telling me what I did when I didn't do it and told him to give me my parts. He wasn't trusting a single word coming out of my mouth when he refused to listen to me and kept telling me the engine was against the rev limiter and I told him I never hit the rev limiter. If he can't trust my words then I can't trust him. Once I saw what happened internally in the engine after collecting my parts, I understand why he didn't want to listen. Your experience and mine are drastically different in dealing with him. He built me a bomb..........a bomb that only lasted 325 miles and 5 hours of run time. Do the math 325 divided by 5 = 65 mph average. I've said all along that 95% of those miles were driven on the Interstate highway system. Nobody wants to say anything about the car that lost the 6.2L engine at the Texas Mile in March. Why did it stick a rod through the block and catch fire? Now everybody looks at the other car built by another engine builder that lifted the head gasket at the Arkansas Mile and don't want to talk about it. I at least know why that one happened. The turbo wastegate controller lost control of boost. The ECU was commanded for 23 psi of boost, but the wastegate let the boost go to 35 psi with stock MLS head gaskets. At that boost levels the engine needs copper head gaskets. The problem wasn't engine related it was caused by a wastegate controller problem.

 

[jazz05]

I dont disagree bc, but exposing the whole core and removing that back plate, which acts as a huge aluminum heat sink has a lot of theoretical benefit, I have spent some time talking to Shawn as well over the years, wish I had texas size oil money but i have to live in the real world