Belt Slip or Boost Leak? Dyno Graph Inside
Thread Starter
Joined: Aug 2002
Posts: 10,331
Likes: 1
From: San Antonio, TX
Originally Posted by 1dirtyZ
does your dyno support boost logging?
on my graphs, the is a boost line with A/F line.
ask your shop if they do, it'll tell you definatly is you have a boost leak/belt slip.
force fed, copyright dude, copyright!
on my graphs, the is a boost line with A/F line.
ask your shop if they do, it'll tell you definatly is you have a boost leak/belt slip.
force fed, copyright dude, copyright!
KP i dont think the verter was locked.... im going to have Jayson lock it next time i hit the rollers..... im going to video it also..... My whole kit is off the car and me and TTldLS1 (Tommy) are going to reinstall the whole kit to make sure there is no leaks at all......... We took the whole front bumber support off tonight and man theres some room in there........ im going to save up and do a FMIC with hard tubing and see what this D1-SC can do..... i bet there never should of been a reason for people to upgrade to a F1-R......
Ill post pics tomorrow.
Kyle
Unlocked graphs look pretty flat and like I said if you are staring at the boost guage when you nail it thw boost will shoot right up to 5psi and stay there for a long time since the engine RPM is just sitting at one point until the rear tire speed catches up and the engine rpm starts rising (thats what high stall converters do). So it would appear that the boost 'hangs' for a while, I dyno cars quite a bit and I have seen the same thing with an unlocked converter dozens of times. The RPM graph on a dynojet is all wrong unlocked with a large stall also.
I lose 25rwhp unlocked (yank pt4200), if your tune was off up high or it was detonating you could easily loose another 20-25rwhp up top. So if you would have played with it a little and locked the coverter you possibly could have made 550rwhp with that amount of boost. Plus you didnt pull the motor very high it appears. Put a 3.4 pulley on it would get another 1.5-2psi and there would be your 600.
I'm not saying you dont have a leak, I picked up almost 1 full PSI getting rid of that POS ATI bypass. I assume you do have a check valve in the pcv. Your intake could be leaking, cracked intercooler - could be a lot of things but I dont think you are as far off as you think you are. Has anyone asked the guy who is number one on the boosted list what pulley combo he is running to make 12psi on a h/c 388?
I lose 25rwhp unlocked (yank pt4200), if your tune was off up high or it was detonating you could easily loose another 20-25rwhp up top. So if you would have played with it a little and locked the coverter you possibly could have made 550rwhp with that amount of boost. Plus you didnt pull the motor very high it appears. Put a 3.4 pulley on it would get another 1.5-2psi and there would be your 600.
I'm not saying you dont have a leak, I picked up almost 1 full PSI getting rid of that POS ATI bypass. I assume you do have a check valve in the pcv. Your intake could be leaking, cracked intercooler - could be a lot of things but I dont think you are as far off as you think you are. Has anyone asked the guy who is number one on the boosted list what pulley combo he is running to make 12psi on a h/c 388?
Thread Starter
Joined: Aug 2002
Posts: 10,331
Likes: 1
From: San Antonio, TX
Originally Posted by kp
Unlocked graphs look pretty flat and like I said if you are staring at the boost guage when you nail it thw boost will shoot right up to 5psi and stay there for a long time since the engine RPM is just sitting at one point until the rear tire speed catches up and the engine rpm starts rising (thats what high stall converters do). So it would appear that the boost 'hangs' for a while, I dyno cars quite a bit and I have seen the same thing with an unlocked converter dozens of times. The RPM graph on a dynojet is all wrong unlocked with a large stall also.
I lose 25rwhp unlocked (yank pt4200), if your tune was off up high or it was detonating you could easily loose another 20-25rwhp up top. So if you would have played with it a little and locked the coverter you possibly could have made 550rwhp with that amount of boost. Plus you didnt pull the motor very high it appears. Put a 3.4 pulley on it would get another 1.5-2psi and there would be your 600.
I'm not saying you dont have a leak, I picked up almost 1 full PSI getting rid of that POS ATI bypass. I assume you do have a check valve in the pcv. Your intake could be leaking, cracked intercooler - could be a lot of things but I dont think you are as far off as you think you are. Has anyone asked the guy who is number one on the boosted list what pulley combo he is running to make 12psi on a h/c 388?
I lose 25rwhp unlocked (yank pt4200), if your tune was off up high or it was detonating you could easily loose another 20-25rwhp up top. So if you would have played with it a little and locked the coverter you possibly could have made 550rwhp with that amount of boost. Plus you didnt pull the motor very high it appears. Put a 3.4 pulley on it would get another 1.5-2psi and there would be your 600.
I'm not saying you dont have a leak, I picked up almost 1 full PSI getting rid of that POS ATI bypass. I assume you do have a check valve in the pcv. Your intake could be leaking, cracked intercooler - could be a lot of things but I dont think you are as far off as you think you are. Has anyone asked the guy who is number one on the boosted list what pulley combo he is running to make 12psi on a h/c 388?
Kyle
TECH Senior Member
Joined: Nov 2001
Posts: 11,603
Likes: 0
From: Chi-Town, IL
I'm sure I don't have any leaks by the amout of boost I saw with the COGS....
I have a upgraded BOV, so thats taken care of, I've just been without a successful pulley setup...
Hopefully SD can come through
I'm still waiting on parts though, I'm going w/the 3.2"
I have a upgraded BOV, so thats taken care of, I've just been without a successful pulley setup...
Hopefully SD can come through
I'm still waiting on parts though, I'm going w/the 3.2"
Thread Starter
Joined: Aug 2002
Posts: 10,331
Likes: 1
From: San Antonio, TX
Originally Posted by BIGBOS
I'm sure I don't have any leaks by the amout of boost I saw with the COGS....
I have a upgraded BOV, so thats taken care of, I've just been without a successful pulley setup...
Hopefully SD can come through
I'm still waiting on parts though, I'm going w/the 3.2"
I have a upgraded BOV, so thats taken care of, I've just been without a successful pulley setup...
Hopefully SD can come through
I'm still waiting on parts though, I'm going w/the 3.2"
Kyle
TECH Senior Member
Joined: Nov 2001
Posts: 11,603
Likes: 0
From: Chi-Town, IL
I'm using the ATI race ready BOV, its $400 new, I got it from Speed Inc.
www.ls1speed.com
Its sitting in the location that was across from where the stock BOV was, from where the tube went to the other piping....you can see it in some of my COG pics in my webshots.....its red and large
www.ls1speed.com
Its sitting in the location that was across from where the stock BOV was, from where the tube went to the other piping....you can see it in some of my COG pics in my webshots.....its red and large
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Verdad Gallardo Thread Starter
Joined: Aug 2002
Posts: 10,331
Likes: 1
From: San Antonio, TX
The whole front of the car is off...... i know i can fit a big FMIC in there......... no i just need to find a new bypass valve...... BOS the one you have isnt on Speed inc's site......
Im going to have to find a new home fro my tranny cooler..... I just have to map out how im going to run the tubing and if its going to be hard pipe like i am wanting.......
Kyle
Im going to have to find a new home fro my tranny cooler..... I just have to map out how im going to run the tubing and if its going to be hard pipe like i am wanting.......
Kyle
