rocket5979

iTrader: (1)

Your point is not founded upon any thermodynamic logic. The TS blower is not in boost the whole time though it does still compress air inside it's case. If it was producing boost then the vacuum bypass would not suck open, due to lower manifold vacuum, to allow air to flow directly from upper plenum to lower plenum, entirely bypassing the supercharger. If your logic applied then that would mean that ALL TS based systems would not be able to achieve decent post-blower IAT's whether they be in a Ford or GM vehicle because they are "in boost" all the time. You might want to actually have some firsthand knowledge about how the vacuum bypass systems work on positive displacement superchargers before you start making technical comments on them. PD blowers, which include Eaton roots, Maggie TVS, Whipple TS, Kenne Bell TS, and Eaton TS HAVE to have the vacuum bypass because when they are not in boost (aka while the engine is idling or very light throttle) the blower is not moving enough air to support the engines minimum airflow requirements. Without a vacuum bypass it would starve the engine for air and it would shut off. That is the purpose of the vacuum bypass. Not for cooling post-blower IAT's or cooling the blower itself. That is the purpose of the AWIC system.








I have designed and built custom PD blower systems based on Kenne Bell blowers and Eaton blowers before so I know a thing or two with what you need to take into account when executing a kit. I cannot speak for those guys building the LSx vehicle specific Kenne Bell based systems but if their post-blower IAT's are way out of whack then that leads me to believe that the AWIC is too small or that the HE, or IC pump are too small or the the air filter inlet is in the wrong location in the engine bay.... or a combination of those. Also as others have said in here with a PD blower your IAT's will be hotter than other forms of FI which will require more tuning in the IAT spark table to ensure that you aren't commanding too much spark and causing knock due to not accounting for higher than normal post-blower IAT's. Zeroing out the IAT spark table, especially on a PD blower, is tantamount to flying a jetliner blindfolded. You just don't do it.

rocket5979

iTrader: (1)

If the blower isn't sized or configured correctly for the combo. When sized correctly it will pull one hell of alot longer than after 2700rpms. Take a look at what some of the 2.2 liter blowers did on the 03-04 Cobras.




Yes and no. If the AWIC system is sized right and you actually are flowing enough coolant through the blower then it will not heatsoak and power numbers will be pretty consistent. This means that the AWIC unit under the blower itswelf, the HE in the front bumper, and the IC coolant pump for starters have to be sized large enough to support the cooling requirements. However, most of the time people run AWIC system components that are too small to constantly overcome heatsoak. That is when you run into situations where the car makes great power the first run and then every run after that just drops off like a stone due to post-blower IAT's shooting through the roof causing spark timing to be retarded (with a properly tuned IAT Spark table ) because the AWIC system cannot keep up.

bowtiebuilder

iTrader: (18)

[QUOTE=rocket5979;13542936]If the blower isn't sized or configured correctly for the combo. When sized correctly it will pull one hell of alot longer than after 2700rpms. Take a look at what some of the 2.2 liter blowers did on the 03-04 Cobras.



Good friend of mine has the Kenne bell 2.8 on his 04 cobra and just put down 606 wheel on 15 lbs. And I can assure you that the power band went just a little further than 2700.

ysb02

IATs like that I can deal with probably in the TX heat. Do you ever road race your z06? I was debating going with a TVS2300 setup on my c5z and changing to a lower boost pulley whenever I went to the road track to keep IATs down.

robert miller

[QUOTE=bowtiebuilder;13543426] I am just saying for what I was looking for from the kenne bell and was told and was told just big tells what it would do on the corvette. Just junk on the vettes. The car will pull after 2700 but per say that was the hit of the kenne bell. After that it was more just the motor.

backchannel

I don't roadcourse this car anymore but at lower boost levels, I would expect less heat buildup than a centri without meth. Dynoing the tvs-second run is very close to the first and they all repeat to the second run. Centris without meth do not repeat by the third run. How many centri owners use their third or fourth dyno run as their power quote. Of course if you want 1000 rwhp, then centri/meth or turbo
The ATW intercooler and heat exchanger keep iats stabalized very well at speed. The major heat soak is from the aluminum manifold and can be addressed. I haven't heard any complaints from users that actually own tvs and expect if the attention is paid to the cooling used with KB that it should be similar. I am considering trying a KB to see if it will hold boost to redline.

novaflash2002

iTrader: (51)

rocket5979 - it depends if the bypass valve is working before the intake air charge goes through the rotors, or if it is after the air is compressed. if it is after, than my statement is correct; if not, i agree that i am wrong. from what it looks like it is after the air is compressed. when u compress air it heats up.

ysb02

The big problem I have with a centri is the A2A IC blocks the radiator more than the A2W IC the Magnacharger kits does. I've heard/seen people on the road course with low-boost maggies but haven't seen anyone with a centri. I'm not looking for 1000rwhp, maybe 700rwhp tops with a built motor.

rocket5979

iTrader: (1)

The entire purpose of the vacuum bypass in a PD blower system is to allow an air path that circumvents the blower (rotors) themselves. Aka non-compressed air making its way into the engine while at part throttle or idle. The vacuum bypass valve will always have a path that takes air from just before the compressor housing to underneath where the lower manifold sits. That is its WHOLE purpose. It is a VACUUM bypass in the PD type blowers, not a boost pressure bypass like in centri and turbo systems. Keep that very important piece of information in mind here. Nova I am not meaning to sound like a jerk but you are dead wrong here. Take a very close look at positive displacement blowers in person and understand the physics behind how they work differently than a centri blower type setup. I have built these systems, centri systems, turbo systems and so on from scratch before which means that in order to affectively accomplish something like this I have to know what components do what and for which specific reasons. I also didn't understand all the key differences until quite a few years ago when I first started really doing custom systems involving this stuff. Most people just bolt these things on without fully understanding why they work the way they do.

The reason I even say that last sentence above is because of the OP asking his questions in here. When a person is trying to figure out the best way to accomplish a PD blower, whether it be TS or TVS type, then it is best spelled out clearly and exactly how things function and what affects what with specific regard to post-blower IAT's. The bottom line is that you are only serving to misguide the OP when going off on tangents about the vacuum bypass valve sizing, which has virtually nil to do with actively controlling IAT's and heatsoak in a PD blower setup. The AWIC system is the item that would need to be looked at in this case.

icen

AWIC is too small or that the HE, or IC pump

now that we know the "problem." What do you reccomend to fix it specifially. Such as xyz brand AWIC will be large enough, etc.

I have a 2.6l KB on my c6, puttin down 536whp and a table of 530tq from 1800 to just shy of redline @ 11psi. Which I thought was weak, i was expecting 600. After having it for a while now. I know its not the best design, but that KB sound nothing like it. Everything yall said is correct AWIC, HE, and IC pump are too small.

ysb02

Are you able to replace the AWIC in the KB intake? I thought you could only change the HE / IC pump.

z28MP

iTrader: (7)

I've seen what appears to be suggestions on getting this to work on cf and a couple over here. Are any of these proven to work or are they just suggestions? I'm looking for what I can do to make this thing run, I don't care about money but, if I can spend like 1k instead of 3k to get it to work I'd rather do that. Thanks for all the input guys learning a lil more everyday.

rocket5979

iTrader: (1)

Well the issue is that unless you want to do some custom re-fabrication of the lower intake plenum then it will be difficult to fit a different or bigger AWIC under the blower. It is definitely possible but it will be a challenge for a person with average mechanical and fabrication skills. But what can be done is running a much larger HE and IC pump. Doing these two items will significantly decrease heatsoak, especially while cruising. If you want to go the extra mile and have the room then you can install pusher/puller fans onto the HE to help keep things even cooler while sitting there waiting in traffic. Also make absolutely sure that the entire AWIC system is burped of any air trapped inside. Any air cavitation will cause coolant flow issues and really hinder the AWIC systems affectiveness. Also distilled water transfers heat better than most coolants, though it will freeze too. If you live in a warm climate that doesn't have much chance of freezing then mix a higher ratio of distilled water in. If you are real serious about getting the maximum cooling then you can always install an icebox that cools the coolant going through it.

novaflash2002

iTrader: (51)

like i put in my post, if i am wrong than i am wrong. I just said it was a bypass; not a vacuum bypass. yes i know it does need vacuum to open a vacuum bypass.

robert miller

What you are saying is true here. Just for the money just much better units out on the market with a ton less problems. With no IAT and heat problems. Also dont have to be doing work on replaceing pumps and the hope it will work. What really got me was all the heat and didnt make the RWHP that I was told it would make. If it was mid day out side and Jeff at TPE told me it was day light outside I would have to look to make sure cause all of the lie,s he tells.

Packy

iTrader: (11)

Here is an option for the Harrop S/C.

http://www.youtube.com/watch?v=v7egN...layer_embedded

http://www.youtube.com/watch?v=6ii5a...layer_embedded

backchannel

Well I was intending to do this blower thinking it was an upgrade. After talking to KB and to Jeff, I now understand why I can't find any testimonials of praise.

Big_Bird_WS6

iTrader: (7)

the maggies are nice. but once you get to like a427 motor you can flow enough air.

Ron at vengance saide they ahve done a few 3.6L Kenne bells in a f-body ubt he had to use the L92 heads.

what do you guys think of a 3.6L KB on a 427?

robert miller

I am thinking you will chg the set up down the road. The kenne bell has never put down any big #. to the turbo,s and the cenfi unit or prochg set ups. Plus with the IAT problems that all of the kenne bell has had. The thing is just a big heat blanket if it goes to the track at all. If your CI is over 383 go with the 2.8h KENNE BELL if you dont chg your mind. But dont believe **** that jeff tells you. If you do it will cost you for sure. Just ask how I know that....

kbracing96

iTrader: (25)

This is what I have planed to help the IAT's with the 2.8, I'm gonna put on my truck. It's a M5 pre-blower and M14 post...






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