Boost Falling Off . . .
Thread Starter
Drifting
Joined: Jul 2015
Posts: 1,679
Likes: 343
From: NY
Boost Falling Off . . .
Was curious if anyone has experienced boost falling and what the remedy was after troubleshooting...
2017 A8
F1R Procharger w/4.25 pulley, stock lower.
Seeing 20 pounds of boost, car is making 820whp on mustang dyno on pump. Problem is at 6200rpm the power falls off drastically. With the stock 4.5" pulley it pulled to 6500rpm. Ive been looking at an array of dyno sheets and im seeing most are 6500-7000rpm.
I dont think its belt slip, we have the belt cranked tight. Only thing we're thinking now is a possible blockage with the intercooler. But wanted to see if anyone else had a similar issue before we started hacking and welding bung on my charge pipes to test.
Procharger admits theyve seen issues with their intercoolers an also states it should be making more power at 20 pounds and the blower is not maxed with only 58K rpm on it.
Any insight is appreciated!!
2017 A8
F1R Procharger w/4.25 pulley, stock lower.
Seeing 20 pounds of boost, car is making 820whp on mustang dyno on pump. Problem is at 6200rpm the power falls off drastically. With the stock 4.5" pulley it pulled to 6500rpm. Ive been looking at an array of dyno sheets and im seeing most are 6500-7000rpm.
I dont think its belt slip, we have the belt cranked tight. Only thing we're thinking now is a possible blockage with the intercooler. But wanted to see if anyone else had a similar issue before we started hacking and welding bung on my charge pipes to test.
Procharger admits theyve seen issues with their intercoolers an also states it should be making more power at 20 pounds and the blower is not maxed with only 58K rpm on it.
Any insight is appreciated!!
Safety Car
Joined: Oct 2007
Posts: 4,206
Likes: 1,075
From: South Florida
Every FI setup needs to be pressure tested. Simply use an air compressor to push air into a vacuum hose and block the blower inlet using a PVC cap with a hose clamp. make sure you remove any crankcase vent tubes- do not pressureize the crank case. Keep the dipstick pulled up so you can tell if anything is going in there.
Last edited by Kingtal0n; Oct 26, 2018 at 11:50 AM.
Racer
Joined: Oct 2013
Posts: 260
Likes: 12
Thread Starter
Drifting
Joined: Jul 2015
Posts: 1,679
Likes: 343
From: NY
I intend on going with a griptech pulley first then see whats going on. Followed with the LME intake. HOPING the PC standard intercooler is as advertised and can keep up.
Racer
Joined: Oct 2013
Posts: 260
Likes: 12
Former Vendor
Joined: Sep 2016
Posts: 1,397
Likes: 267
From: Houston Texas
Was curious if anyone has experienced boost falling and what the remedy was after troubleshooting...
2017 A8
F1R Procharger w/4.25 pulley, stock lower.
Seeing 20 pounds of boost, car is making 820whp on mustang dyno on pump. Problem is at 6200rpm the power falls off drastically. With the stock 4.5" pulley it pulled to 6500rpm. Ive been looking at an array of dyno sheets and im seeing most are 6500-7000rpm.
I dont think its belt slip, we have the belt cranked tight. Only thing we're thinking now is a possible blockage with the intercooler. But wanted to see if anyone else had a similar issue before we started hacking and welding bung on my charge pipes to test.
Procharger admits theyve seen issues with their intercoolers an also states it should be making more power at 20 pounds and the blower is not maxed with only 58K rpm on it.
Any insight is appreciated!!
2017 A8
F1R Procharger w/4.25 pulley, stock lower.
Seeing 20 pounds of boost, car is making 820whp on mustang dyno on pump. Problem is at 6200rpm the power falls off drastically. With the stock 4.5" pulley it pulled to 6500rpm. Ive been looking at an array of dyno sheets and im seeing most are 6500-7000rpm.
I dont think its belt slip, we have the belt cranked tight. Only thing we're thinking now is a possible blockage with the intercooler. But wanted to see if anyone else had a similar issue before we started hacking and welding bung on my charge pipes to test.
Procharger admits theyve seen issues with their intercoolers an also states it should be making more power at 20 pounds and the blower is not maxed with only 58K rpm on it.
Any insight is appreciated!!
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Burning Brakes
Joined: Nov 2015
Posts: 1,160
Likes: 40
From: Kuwait
Another way that i would think of is to make the intercooler outlet piping diamter to 3.5” or even 4, so you can have less restrictions, if you have the procharger race intercooler i know its flow good up to 1100whp, so its either a boost leak or belt slip
keep us updated and good luck
keep us updated and good luck
Thread Starter
Drifting
Joined: Jul 2015
Posts: 1,679
Likes: 343
From: NY
Another way that i would think of is to make the intercooler outlet piping diamter to 3.5” or even 4, so you can have less restrictions, if you have the procharger race intercooler i know its flow good up to 1100whp, so its either a boost leak or belt slip
keep us updated and good luck
keep us updated and good luck
Thanks for the responses!!
Looking at the 10 rib setup, would like to have everything done on that end and eliminate belt slip as a possibility.
G1pro has a larger core procharger kit replacment intercooler so after that option ill kick the tires on that. Lastly going to the LME intake, not for the boost drop issue but for performance. Guys with these setups seem to be bolting on big power with this over the procharger intake.
Former Vendor
Joined: Sep 2016
Posts: 1,397
Likes: 267
From: Houston Texas
Thanks for the responses!!
Looking at the 10 rib setup, would like to have everything done on that end and eliminate belt slip as a possibility.
G1pro has a larger core procharger kit replacment intercooler so after that option ill kick the tires on that. Lastly going to the LME intake, not for the boost drop issue but for performance. Guys with these setups seem to be bolting on big power with this over the procharger intake.
Looking at the 10 rib setup, would like to have everything done on that end and eliminate belt slip as a possibility.
G1pro has a larger core procharger kit replacment intercooler so after that option ill kick the tires on that. Lastly going to the LME intake, not for the boost drop issue but for performance. Guys with these setups seem to be bolting on big power with this over the procharger intake.
Thread Starter
Drifting
Joined: Jul 2015
Posts: 1,679
Likes: 343
From: NY
Le Mans Master
Joined: Aug 2001
Posts: 6,071
Likes: 297
From: Savannah GA
Cruise-In IV Veteran
Another way that i would think of is to make the intercooler outlet piping diamter to 3.5” or even 4, so you can have less restrictions, if you have the procharger race intercooler i know its flow good up to 1100whp, so its either a boost leak or belt slip
keep us updated and good luck
keep us updated and good luck
Burning Brakes
Joined: Nov 2015
Posts: 1,160
Likes: 40
From: Kuwait
I bought this kit to test the pressure on my system. I would do this for sure to check for leaks: https://www.amazon.com/Lisle-69700-T.../dp/B00RGNKQSK
that kind of waste of money, you could do it with s tire tube, cut a rounded 9” peace making the valve in the middle, put it on the procharger inlet with a clamp and apply pressure to it
Team Owner
Joined: Jan 2007
Posts: 29,063
Likes: 1,839
From: cookeville tennessee
I bought this kit to test the pressure on my system. I would do this for sure to check for leaks: https://www.amazon.com/Lisle-69700-T.../dp/B00RGNKQSK
Le Mans Master
Joined: Aug 2001
Posts: 6,071
Likes: 297
From: Savannah GA
Cruise-In IV Veteran
yeah if you have more time on your hands than I do. Sure. You can build a house with popsicle sticks also. Point was to get him in right direction of how to pressure test. Damn guys you tear apart every single person trying to help on this forum. How about just appreciate we all are trying to add helpful content here. ****.
Thread Starter
Drifting
Joined: Jul 2015
Posts: 1,679
Likes: 343
From: NY
I appreciate the replies fellas, hoping its just belt slip. Not sure if i should "waste" the money on a 8 rib griptech or just start moving forward with a 10 rib set up. I dont plan on spinning the blower any hard for some time, once this is figured out.
Burning Brakes
Joined: Nov 2015
Posts: 1,160
Likes: 40
From: Kuwait
yeah if you have more time on your hands than I do. Sure. You can build a house with popsicle sticks also. Point was to get him in right direction of how to pressure test. Damn guys you tear apart every single person trying to help on this forum. How about just appreciate we all are trying to add helpful content here. ****.
calm down brother, all i meant was to save him couple bucks your way is right but cost more than the other way, both do the same thing. Your point was helpful and much appreciated. Nice build by the way and i wish my car was built as professional as yours
Former Vendor
Joined: Sep 2016
Posts: 1,397
Likes: 267
From: Houston Texas