Anybody using Southways 108mm TB?? Having problems with it
#1
Anybody using Southways 108mm TB?? Having problems with it
I installed a Southways 108mm TB and lost 50rwhp on my 468ci LS7. When we pull the car on the dyno and let off it goes into reduce power mode. Do you think the throttlebody plate is shutting closed because maybe the motor is not strong enough to keep it open. It has a brand new OEM motor. Someone was mentioning maybe changing the voltage through the tune to the throttlebody. I think Monday we’re going to put the NW102 back on and see. I just don’t see how I should lose power especially a big cube motor that needs air.
Last edited by 441LSXTT; 01-28-2019 at 12:38 PM.
#2
Team Owner
Bigger isn't always better. I could easily see the MSD being ported like that and lose power.
#3
#4
Team Owner
When it comes to porting, bigger does not necessarily mean more air. Just hogging out runners doesn't mean you are now getting more air. Just like when Richard@WCCH told Josh he can open up the heads for his new intake, but it will hurt flow and power. Hopefully it is just a TB issue with it not opening fully, but as long as it is wide open at WOT, next thing to do would be go back to the old intake.
Last edited by Unreal; 01-26-2019 at 09:04 AM.
#5
Sorry to hear that you are having all of these problems. It is clear to me that it is not easy or cost effective to go from a well thought out LS7 with 630/640whp to 700whp. I don't even want to ask the amount of money that you have put into this motor but it has to be substantial. To me, it would certainly be easier and cheaper to build a lower compression motor and boost it or just stay at the 630whp range.
However, I do understand the rational of having a high revving NA motor, but I am not sure that benefits outweigh the costs.
I don't daily my Z, but I do have a handful of German cars that are boosted and there is no question in my mind that FI on a daily driver is that way it should be.
However, I do understand the rational of having a high revving NA motor, but I am not sure that benefits outweigh the costs.
I don't daily my Z, but I do have a handful of German cars that are boosted and there is no question in my mind that FI on a daily driver is that way it should be.
#6
When it comes to porting, bigger does not necessarily mean more air. Just hogging out runners doesn't mean you are now getting more air. Just like when Richard@WCCH told Josh he can open up the heads for his new intake, but it will hurt flow and power. Hopefully it is just a TB issue with it not opening fully, but as long as it is wide open at WOT, next thing to do would be go back to the old intake.
#7
Sorry to hear that you are having all of these problems. It is clear to me that it is not easy or cost effective to go from a well thought out LS7 with 630/640whp to 700whp. I don't even want to ask the amount of money that you have put into this motor but it has to be substantial. To me, it would certainly be easier and cheaper to build a lower compression motor and boost it or just stay at the 630whp range.
However, I do understand the rational of having a high revving NA motor, but I am not sure that benefits outweigh the costs.
I don't daily my Z, but I do have a handful of German cars that are boosted and there is no question in my mind that FI on a daily driver is that way it should be.
However, I do understand the rational of having a high revving NA motor, but I am not sure that benefits outweigh the costs.
I don't daily my Z, but I do have a handful of German cars that are boosted and there is no question in my mind that FI on a daily driver is that way it should be.
#8
When it comes to porting, bigger does not necessarily mean more air. Just hogging out runners doesn't mean you are now getting more air. Just like when Richard@WCCH told Josh he can open up the heads for his new intake, but it will hurt flow and power. Hopefully it is just a TB issue with it not opening fully, but as long as it is wide open at WOT, next thing to do would be go back to the old intake.
#9
Team Owner
Good idea. Hopefully that was it because it would be sad if you paid someone to ruin your intake. I wouldn't have touched it before, so hopefully it was something else.
#10
Melting Slicks
I would 100% go back to the NW102 and see what happens. Pushing that kind of power you shouldn't drop HP with Tony's MSD. I would definitely say it's the TB. Good Luck!
#11
Team Owner
It's not Tony's MSD anymore though .
#13
Melting Slicks
Don't give up just yet, that motor has a hell of a lot more power in it just waiting to be tapped!!!
Last edited by JMB; 01-27-2019 at 09:41 PM.
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dmartens (02-05-2019)
#15
Burning Brakes
Member Since: Mar 2011
Location: Tampa FL
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St. Jude Donor '13
I agree with your statement but I don't think there is enough meat in the runner thickness where you could remove enough material that the ~7% larger displacement engine would drop peak 50hp by opening up the runners a bit more. I do realize the new ported shape of the runners are probably less efficient than originally ported by Mamo and that could account for some difference. Tony does a great job of keeping port velocities high at lower rpms ranges without sacrificing high rpm flow giving a great power curve. I would guess some of that could be lost with home porting unless you really study where to remove material.
#16
Team Owner
I agree with your statement but I don't think there is enough meat in the runner thickness where you could remove enough material that the ~7% larger displacement engine would drop peak 50hp by opening up the runners a bit more. I do realize the new ported shape of the runners are probably less efficient than originally ported by Mamo and that could account for some difference. Tony does a great job of keeping port velocities high at lower rpms ranges without sacrificing high rpm flow giving a great power curve. I would guess some of that could be lost with home porting unless you really study where to remove material.
#17
Drifting
This, the MSD is only open 102mm I think. You would have to port a ton out of the opening. Pull the intake back apart and mount the 108 to the opening to see if it does hit when you open the blade.
#18
Melting Slicks
I agree with you BUT Tony isn't just any guy with a die grinder. I have never heard of someone losing HP with one of his ported MSD's. He knows what he is doing and puts a lot of time in R&D. Just my 2 cents!
#19
#20
Melting Slicks
The 108 comes with an adapter that must be used when bolting on to a traditional 4 bolt throttle body flange, as the Southways unit uses 8 bolts. This effectively spaces the 108 tb further away from the mouth of the intake
This new MSD intake he is trying is not a stock Mamo ported MSD. It has been extensively modified by another "porter"
This new MSD intake he is trying is not a stock Mamo ported MSD. It has been extensively modified by another "porter"