FAST 102 Install 90MM TB Issues
Thread Starter
8th Gear
Joined: May 2019
Posts: 8
Likes: 1
FAST 102 Install 90MM TB Issues
Just installed a FAST 102 LSXR onto my bolt on 2006 Corvette, there is an extreme lag between off-idle and throttle response and it's made driving the car a pain. I understand it could potentially be a vacuum leak - or the difference between the throttle body & intake opening? Based on my research, VMAX Motorsports makes a "Velocity Ring" - is that still a thing? Is this set-up supposed to have hesitation? Does it need a tune?
2006 Corvette, Texas Speed Longtubes, X Pipe, Corsa Extreme, Varaam SC-1, Fast 102.
2006 Corvette, Texas Speed Longtubes, X Pipe, Corsa Extreme, Varaam SC-1, Fast 102.
Pro
Joined: Mar 2007
Posts: 738
Likes: 226
From: Coast of San Mateo CA
I use and recommend the V Max Velocity Ring for that exact issue, will make tuning
much easier also.
ABSOLUTELY will need a tune for the FAST 102 Intake which flows A LOT more air than
the stock LS2 which is pretty poor.
much easier also.
ABSOLUTELY will need a tune for the FAST 102 Intake which flows A LOT more air than
the stock LS2 which is pretty poor.
Last edited by Navy Blue 210; Jun 26, 2019 at 06:16 PM.
Safety Car
Joined: May 2016
Posts: 4,626
Likes: 1,815
From: Erlanger, Kentucky
Just installed a FAST 102 LSXR onto my bolt on 2006 Corvette, there is an extreme lag between off-idle and throttle response and it's made driving the car a pain. I understand it could potentially be a vacuum leak - or the difference between the throttle body & intake opening? Based on my research, VMAX Motorsports makes a "Velocity Ring" - is that still a thing? Is this set-up supposed to have hesitation? Does it need a tune?
2006 Corvette, Texas Speed Longtubes, X Pipe, Corsa Extreme, Varaam SC-1, Fast 102.
2006 Corvette, Texas Speed Longtubes, X Pipe, Corsa Extreme, Varaam SC-1, Fast 102.
Safety Car
Joined: May 2011
Posts: 3,807
Likes: 508
From: Oshawa, Ontario
You have some sort of issue.There should be no hesitation.Did you use the buttonhead bolts on valley cover when you installed manifold?Mine was not tuned right away when I installed Fast and headers but I did check on dyno to make sure AFR and everything were OK.Dyno at that time showed an increase of 60 rwhp
Thread Starter
8th Gear
Joined: May 2019
Posts: 8
Likes: 1
Update for the issue - I should of read the directions, I did not drill the front MAP sensor hole - the MAP sensor will plug in but it definitely will not see vacuum unless you drill it out. After I drilled the hole in the top, all of my issues are fixed! No hesitation and it drives extremely well even without the velocity ring. Tune is definitely on my list!
Safety Car
Joined: May 2016
Posts: 4,626
Likes: 1,815
From: Erlanger, Kentucky
Update for the issue - I should of read the directions, I did not drill the front MAP sensor hole - the MAP sensor will plug in but it definitely will not see vacuum unless you drill it out. After I drilled the hole in the top, all of my issues are fixed! No hesitation and it drives extremely well even without the velocity ring. Tune is definitely on my list!
4th Gear
Joined: Apr 2019
Posts: 4
Likes: 1
From: McKinney Texas
Update for the issue - I should of read the directions, I did not drill the front MAP sensor hole - the MAP sensor will plug in but it definitely will not see vacuum unless you drill it out. After I drilled the hole in the top, all of my issues are fixed! No hesitation and it drives extremely well even without the velocity ring. Tune is definitely on my list!
Thread Starter
8th Gear
Joined: May 2019
Posts: 8
Likes: 1
I would say it took us approximately half an hour to un-do and re-do, it's the easiest job I've done yet. The only thing you should be mindful of is, there is a pressure sensor in the back right (staring at the engine from the front) of the manifold that the brake booster hose is behind, so when you pull the manifold out the hose catches on and breaks the sensor. When you pull the manifold out, reach back there and move the hose up and over before the final removal.
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Racer
Joined: Oct 2011
Posts: 293
Likes: 6
Glad you figured out your issue. You'll see an even better throttle response with a tune, since the intake manifold volume has significantly changed. Not to mention getting the WOT air/fuel and timing dialed in.
Btw- I have a velocity ring for the FAST102 available. If you're still interested in getting one let me know.
Btw- I have a velocity ring for the FAST102 available. If you're still interested in getting one let me know.