Some talk about TB's and TPS units
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Joined: Mar 2008
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From: North East, MD
Some talk about TB's and TPS units I had a ported at one point on my Buick long ago then switched it to a 70mm when I had the funds and to line up with better with the 3" IC piping. Don't know if it was a noticeable gain other than throttle response seemed a little crisper. Thinking about going ported so wondering what the real world gain is with them? What is the ported size and what is an LS-6 intake have for an opening? I read about the bump stop mod and that is something else I wanted to try to understand.
So unless the LS-1's are different than Buicks in the TB/TPS area you need .42- .47 VDC at idle and anything > 4.5 VDC to trigger power enrichment (WOT signal). We always adjusted the TPS to achieve that. I didn't really see where anyone was moving it here or did I miss that? Seems everyone grinds the bump stop to get about 89 degrees. Does it make much of a flow difference because we never did that. Just fishing for info.
So unless the LS-1's are different than Buicks in the TB/TPS area you need .42- .47 VDC at idle and anything > 4.5 VDC to trigger power enrichment (WOT signal). We always adjusted the TPS to achieve that. I didn't really see where anyone was moving it here or did I miss that? Seems everyone grinds the bump stop to get about 89 degrees. Does it make much of a flow difference because we never did that. Just fishing for info.
Joined: Aug 2007
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From: Turnin' Wrenches Infractions: 005
i think stock intakes openings are 75 mm. the throttle bodies arent exactly that much so porting them brings them up to 75mm to match the size of the intake opening. the shaft that holds the blade gets cut bc it interfers with airflow. i have heard about 5 to 10 hp but after i got mine done it felt the same. i mean lets be honest 5 hp on a 50 hp motor is a lot. 5 hp on a 350 hp motor is prolly very hard to tell. my stall converter prolly keeps me from noticing the throttle response difference bc when you press on the gas the motor kinda free revs more or less. as for bumpstop mod i have seen some pics of throttle blades that werent even close to 90* open. so im sure it helps but if you can actually FEEL it i dunno. there is a good thread on here about bumpstop mod. i think 4.71 volts is getting close to throwing a code.
