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204 Posts
Discussion Starter · #1 ·
Sound Performance (my experience/thoughts)

sound (adj.):

*Free from defect, decay, or damage; in good condition.
*Having a firm basis; unshakable: a sound foundation.
*Based on valid reasoning: a sound observation.
*Free from logical flaws: sound reasoning.
*Thorough; complete: a sound flogging.
*Worthy of confidence; trustworthy.
*Marked by or showing common sense and good judgment; levelheaded: a sound approach to the problem.

performance (noun):

* an act or process or manner of functioning or operating

After visiting the idea of going single for several months and seeing a local Supra with a TS04 on his car, I started talking with Larry Prebis at Sound Performance in March of 2001 about the possibility of going single and using one of his kits. I originally heard about Sound Performance when I owned my 1991 TT 300ZX, as they had become well known in the Z community for the Cheetah, Tim Liess's yellow Z. Larry at the time had also run a 9.54 in his daily driveable Supra, AC included. This was something I could relate to as I did not want to give up the comforts of the Supra, ie AC and full interior while maintaining the daily driveability. I had no desire for a trailer queen that saw the drag strip once a week and only ran on C-16, but one of the monsters they promoted their shop with that I could take out of town on a long distance trip and still run pump gas in.

In March, I made the decision to upgrade, but Larry told me to wait and his new kit would be well worth the wait. Needless to say, the kit FINALLY shipped on August 7th, after my car had been down for about a month and a half after tearing it down for some suspension upgrades and pulling the stock twins off at the same time. It was like Christmas!!!!!!!! I had the very first new kit that Sound Performance had produced with the SP 63 and it was amazing. Everything was wrapped up perfectly so nothing got scratched or dented. At the same time, I ordered the SP fuel system, a GForce computer upgrade through SP, and a Nitrous Express wet kit from NX. Larry gave me top notch technical support throughout the installation of all the parts, even had his home number and had to make a couple of calls on Sunday trying to figure some things out. Being the first to get something new is cool, that is, until I started encountering fitment and installation problems. Needless to say, some things did not line up very well, and certain parts went under slight modifications as I talked with Larry on what I liked and did not like with the kit for future owners. Hopefully all of you that have bought kits from my recommendations have profited from my pains, experiences, and feedback with Larry.

The SP63 was UNBELIEVABLE, and with the nitrous as a spoolup and later using it all the way through, the car was fast as hell. It dynoed 604 rwhp/590 lbs of torque at 29 psi and then 670/674 with a 70 shot of nitrous. The TRD clutch went bye bye the first pass I tried to make with it, which then was replaced by the AZ disk and stock flywheel, which then snapped a driveshaft in half. I noticed the cars power start to fall off at around 6600 rpms, so I went to Atlanta and had Phil Panas help me install some HKS 272 cams in the car. They completely sucked with that turbo, and TOTALLY changed the driveability of the car. I HATED IT!!!! Went to tune the car on January 27th, and due to myself trying to rush a fuel pump fix the week before, one of the filters had not been fastened securely on one of the pumps and came off. Needless to say, on the last run of the day, after acheiving a perfect 12 to 1 AFR across the board, I used the nitrous, fuel pump failed, and blew my motor. 666 lbs of torque at 3300 rpms, with an AFR that went off the scale. A week later I towed it home and started pulling everything apart. The annual Texas meet was coming up at the end of March, and I saw no way of finishing the motor swap before then. I spoke to Larry again on Thursday, February 22nd, and he said if I could get him the car that weekend, he would have it done in time for me to go to Texas. On Friday, Brad Mayo and myself put the car on the trailer along with the boxes of parts that we had disassembled from the motor, and headed to Chicago after dinner, 10 pm. We drove all night, and arrived in Chicago about 530 am and proceeded to try and sleep in the parking lot of Sound Performance. We dropped the car off after talking with Larry, confirming the completion date by TX2K2, and were back in Knoxville by 11 that night.

Larry and I discussed the new SP74 along with the SP intake manifold and a couple of other custom things to go along with a fully built motor, ported head, EVERYTHING. We were raising the bar, and working as a team if you will, on what was going to come. The crazy thing about the SP intake manifold is the responsibility I took for getting all of the information for it along with a working model to build off of, more time and money that I invested in trying to help Sound Performance offer more to the Supra community. We had even looked into getting custom pistons made along with several other supra owners, but I ended up with Arias pistons per Larry's recommendation. The original estimate was for a little over $9,000.

The Texas meet came and went, April came and went, and so did most of May. Three months went by, and I finally got the call to come pick it up at the end of May, two months after I was promised it would be ready. During the three months it was at Sound Performance, I received updates including pics every now and then from Max and Larry on the status of my car. I arrived on a Thursday, when I was told to come and get it, and on Friday night the car was still not running. I guess Larry saw how pissed off I was at the idea that it might not be till Monday before the car was ready and that it was not acceptable as I had already taken several days off work to be there when I was told to be there. I stayed with Max Thursday night, and then Friday night SP put me up at this nice hotel a couple of blocks away, Indian Lakes or something. On Saturday, people were rushing to get the car done, and could never get the boost controller to work. Needless to say, I left Sound Performance Saturday night at 11pm with a engine that had less than a 1/4 of a mile on it and a car that overall did not run right. I was told the AEM would fix all of the problems and to bring the car back after I had broken in the motor. I also left with a bill for $15,000, $6,000 over the initial estimate, which I am still paying on a year later. I was also blessed with some of my brand new Fikse Aros now sporting some sort of chemical spots, dents in my roof from where at least one of the mechanics decided to take smoke breaks while the targa was off which I saw while I was there, and water spots etched into my paint from sitting outside for so long.

I started to break the motor in on the way home, varying the rpms, doing as I was instructed. Thankfully, the car made the 8 hour trip back to Knoxville, staying out of boost, and giving me a couple of scares on the way home. I spent a good amount of time removing the downpipe and manifold off of the turbo kit once I got home in order to get the wastegate off, which is the conclusion that we eventually came to was causing the boost problems, thankfully still under warranty Larry said. I paid to ship a new one from Sound Performance over night for Saturday delivery, reinstalled everything and once again had boost control through the wastegate. Also, I lost power steering about half way home from Chicago. The power steering reservoir had been fabricated and rewelded in order for the manifold to fit, and then rewelded back to its original setup. Metal slag had worked its way into the power steering rack, thus burning it up and requiring a new rack and a new pump, putting the car out of comission for another several weeks. (Sound Performance DID credit me on this when I went back up in August to have the AEM installed). Two weeks after I got back with the new motor, the timing belt tensioner pulley bracket snapped in half, once again requiring the car to sit as parts were ordered.

I arrived on a Thursday morning in August in Chicago and they started on my car and worked on Friday also, installing the AEM, a 5 bar map sensor and a FJO. The initial estimate on dyno time to get the car running was 2 hours, but ended up being 6 hours. Max tuned the car to the best that he could, and had never worked with an AEM before. Not sure why I was paying for one of Sound Performances mechanics to learn how to operate/tune the AEM engine management system. And to this day, Max telling me that he should have been one of the last people to tune it as he had never done it before is still unsettling. We finally hit 900.4 rwhp at 34 psi a little after 9pm, the last time this car ever saw that kind of boost pressure or that kind of power. I left that Saturday with a new bill of $4,860, quite a bit more than I had expected and a car that ran with a 10.4-10.8 to 1 AFR at idle, cruise, and WOT, stumbling and dying whenever you came to a stop or slowed down really quickly. Needless to say, the gas mileage sucked, getting around 12-14 mpg on the highway and 8-10 roughly in the city. That bill included the AEM and FJO along with the tuning and rewiring that the past mechanic, the one that sat on my roof, screwed up the first time I was there. It also included rewiring of the nitrous system that did not work as it was supposed to and I was told not to use. So basically, I just paid almost $5,000 for a car that runs worse than before and "modifications" that I can not use.

204 Posts
Discussion Starter · #2 ·
Part 2.

At the beginning of October the clutch let go, putting the car out of comission. It sat for another couple of weeks as I waited to get my Horsepower Freaks clutch and Fidanza flywheel installed. And once again, the joy of breaking in a clutch, 1000 miles of no boost.(relevance to come)

In December, I was driving home from a photo shoot down the interstate on a Thursday night at around 5pm. The car all of a sudden died on me at 55 mph, so I proceeded to restart it and make my way off the interstate. Once off the interstate, the car died again, and this time for good. Called a tow truck to get it back to the house. Pulled the plugs and did a compression check, getting ZERO in every single cylinder. After calling Larry, he said that was not possible and that maybe the gauge was broken. After testing the gauge, I found out the horrible fact that it was correct. The engine that I had paid a large amount of money to Sound Performance was completely dead after 4,000 miles, 2,000 miles of it being break in and no boost, and the remaining amount seeing over 18 psi on two different occasions, the first time on the dyno and the second at 28 psi on the drag strip 2 months before, for 3 passes before the clutch let go.

What was the problem? The timing belt tensioner pulley bracket broke AGAIN. At this point, I was still paying for the last 2 bills that Sound Performance had given to me, so I decided to let the car sit. After lengthy discussions on WHY the timing belt tensioner pulley bracket was breaking, and no answers, Larry offered to fix the head for free using used parts that they already had. This really was not that great of a compromise as Larry had said he would need to pull the motor and fix the head as the car smoked horribly and burned lots of oil, and would do it for free anyways.

How long would it take? "Oh, a couple of weeks, but we will make it a priority."

The car was dropped off in Chicago once again, this time the middle to end of January. The head was back in a couple of weeks, but then sat for several weeks with nothing done to it. I would like to thank Max, who spent a good amount of time working on my car to make sure I could have it by Texas of this year. AMAZING!!!!! I was trying to make it to TX2K2 and at this time not even sure if i am going to make TX2K3 with a running car, but i guess that is still to be decided. I fly out of Knoxville on the 26th of March at 9 am and arrive in Chicago at around 10:30 am. I then take a cab to Sound Performance from the airport and get to Sound Performance a little before noon. The car was ready I was told and we prepare to leave around 4:30. I find new scratches in the paint on the doors and sideskirts that looked like something scraped against them. I go to start the car up and it idles like crap. Go to back it up and it dies. Max tells me "We will fix it in Texas." So after fighting to keep the car running in Chicago and just trying to get it to start at Jerry's house, we finally hit the road for Houston around 5 pm. The car blows an intercooler pipe off on the way down there. No big deal. Larry and I fix it, but the car will still not idle and keeps dying. I will say that the gas mileage was ALOT better, now getting 21-22 mpg on the interstate and still seeing some room to improve on it. We drive all night, only fighting the starting issues whenever we stop for gas.

We arrive in Houston a little after 1pm on Thursday after finding out that the car has no working AC now. We check into our hotel rooms, and I go to wash the car. Peter Blach, Tim Iacoli, and myself take Tim's car and my car out onto the expressway. Tim was having problems with his car, so I decided to be a chase car just in case. After pulling off the expressway and tightening some clamps on his intercooler pipes we got back on the interstate. Everything seemed to be good with Tim's car so we decided to see how the cars would do against each other. Look at all my gauges and everything seems to be fine. Tima nd I both hit it in third and at around 6600 rpms the car starts to just fall on its face and fill with smoke. We both pull over on the side of the interstate, pop the hood, and there is oil everywhere. GREAT!!!!!!! Car runs for approximately 30 hours and THE MOTOR IS BLOWN!!!!!! We thought and hoped that it was the front main seal, but unfortunately it was not. Checked the boost gauge recall and it was 18 psi.

The car was left at RSI in Houston and then towed to Performance Motorsports in Austin, Texas after Larry told me "Its a long tow ride back to Knoxville" and Gary said "I don't want to see this car again for awhile." Amazing, I spend $30,000 with a shop and am told this. Even if it was supposed to be funny, it was not. At this point, the quest is on to find out what happened to the motor. Justin Nenni pulls the maps off of the AEM to check Jason Siebels tuning as Larry was pointing to it and the 93 octane I was running. Well, I think we can automatically take out the 93 octane reason itself as there are alot of large single turbo cars, several of those with sp74s, that run around at 18 psi and 93 octane all the time on a stock block with no detonation at all. To think that I just paid $7,000 alone for a built motor would cause one to start questioning the motor build itself or the tuning involved, so we did.

With the tuning, the knock control was left off, one of the first things that was looked into. When I originally confronted Larry about this a week and a half after Texas, he said he did not know and would ask Jason if it was or not. The problem being here is that he checked it immediately upon returning to Chicago, I was told by Max, A BLATANT LIE that I had to continue to question before getting a response, once again Jason's fault he said. Of course there was questioning involved by others who were looking into the AEM:

Customer (1:13:01 PM): but did the people that popped motors actually do anything to have their motors pop?
Customer (1:14:08 PM): for example, i have run 18.5 psi on pump gas with piggy backs all the time
Customer (1:14:12 PM): never had any problems
Customer (1:14:21 PM): should we be able to do that with the AEM?
XXSUPRAXX (1:14:32 PM): yeah, the factory computer can retard the timing
XXSUPRAXX (1:14:41 PM): aem doesnt quite do it as wwelll
Customer (1:14:46 PM): i see
Customer (1:14:57 PM): so what is the solution?
Customer (1:15:21 PM): if the timing is already very conservative(15/16) and the AF is 11.8/1
Customer (1:15:37 PM): the AEM could still blow where the piggy backs may not
XXSUPRAXX (1:16:56 PM): the factory computer will retard the timing back to say 5
Customer (1:17:16 PM): and the AEM?
XXSUPRAXX (1:17:43 PM): you can set it up to retard the timing
Customer (1:18:20 PM): so if it is set up right that should be a good solution
XXSUPRAXX (1:18:36 PM): yes
Customer (1:19:10 PM): so where the people that had motors pop set up wrong?
XXSUPRAXX (1:19:41 PM): most of the time we have kept the timing retard control off
Customer (1:19:47 PM): why?
XXSUPRAXX (1:20:12 PM): Im not sure, but Jason has tuned them all that way
Customer (1:21:19 PM): so to me it looks like the piggy back is a better safer solution than the AEM
XXSUPRAXX (1:22:42 PM): no, not if you turn on the knock retard

204 Posts
Discussion Starter · #3 · (Edited)
Part 3.

So I guess what is being said is if the knock control is turned on, then the motor would have been saved? Interesting. Lets look closer.

The document is called...

AEM EFI Basics...

"If the gasoline-air mixture auto-ignites somewhere in the cylnder (other than at the spark plug) just after spark ignition, the auto-ignition combustion wave can collide with the spark-initiated combustion wave, causing the vibration we hear as a knock or ping. Depending on its intensity, knocking combustion may range from barley audible "pinging" to a rather violent thumping. The point at which the kncoking becomes damgaging to the engine is dependent on the components used in the engine. If sustained knocking occurs, then the pistons may be damaged. When knocking reaches a violent thump, engine operation should be ceased or at a minimum the load and temperature reduced to prevent engine damage. Light knocking that happens during acceleration is less harmful and may not damage the engine. Knocking tendency is increased by the following design or operational characteristics:

-High Engine loads encountered while towing a vehicle.
-Using low octane gasoline in a high-compression engine.
-Too much timing advance for the type of fuel being used.
-Higher air density, (this can be caused by starting a calibration at high altitude and then traveling to a lower one, or the addition of forced induction).
-Increased temperatures and pressure in the combustion chamber due to inadequeate engine cooling.
-Excessive inlet air temperature.
-Spark plugs with an improperly high heat range.
-A non-central spark plug location in the combustion chamber.
-An elongated combustion chamber design.
-Too lean of an air/fuel mixture.

The following tuning adjustments can be performed on an engine to reduce or eliminate knocking:

-Verify that the air/fuel mixture is adequeate for your engine set up.
-Verify that the spark plugs are of proper heat range."

ALSO on page 27!!!

"Before calibration work is to be performed on any engine, find out as much as possible about the engine's critical parameters. These include the engine's compression ratio, the strength of the internal components, the history of the engine, etc."

Interesting. After researching the Arias pistons that Larry said had stock compression, we found out that they were actually 9.6 to 1 INSTEAD of 8.5 to 1 compression like the stock pistons tout. When asked about this, he said he did not realize that and THOUGHT they were stock. So basically, a motor was thrown together without knowing the specs of the working parts and how those parts could change the functionality and tuning of such a motor.

When confronted with the dilemma of the motor being blown and asking for Sound Performance to pay for it, Larry turned me over to Gary.

"I have a hard time paying for something we did not do, but if it is our fault, then we should have to pay for it. Are you saying its our fault that Larry did not tell you that you could not run 18 psi and pump gas?"

Interesting. So if I go to a oil change place and they forget or decide not to put oil in the car and I drive off, is it my fault for not asking them how my car is different from when I drove it in? Details of the motor have been changed and YES, it is the responsibility of the shop to KNOW how and what has changed and how that will effect the car. After telling Gary this, the subject of fixing the timing belt tensioner pulley bracket was brought up when no further answers to my responses could be had. Well...OK...LETS CHANGE THE SUBJECT.

Gary's response. "We fixed the timing belt tensioner problem for you when we should have charged you several thousands of dollars like we could have charged any of our other customers and that was not our fault."

My response. "How was it my fault? Maybe you installed something wrong."

Gary's response. "I doubt that."

My response. "Interesting, since I was sent pics of cam journals being installed improperly, the injector harness was not installed correctly, and there was no air filter on the cold air intake." Several examples of work not being completed correctly, proof that mistakes are made at Sound Performance. Wonder what other parts were not installed correctly and what toll those took on my motor.

Gary's response. "Well, I am not a mechanic so I don't know. I will have to call you back."

Well...once holes were shot in every attempt they made at passing the blame on to someone besides themselves, they proceeded to quickly end the conversation. Still have not heard back from them on paying for my motor they screwed up. The pictures were sent as proof and all the information clearly layed out in detail, YET they still refuse to take responsibility for their mistakes.

I guess we can look at the track record of Sound Performance and the deceit that runs rampant in the supra/automotive community. Gary's car is currently blown up. Larrys car blew up at TX2K2 and made its first pass at TX2K3 the day after it was finished. Ethan has seen more trouble out of his Lexus, with the car basically not running for the last 2 years. Intake manifold was blown apart when the nitrous was fired on startup and put a hole through the hood, which SP paid for BECAUSE IT WAS THEIR FAULT. A motor was blown when Sound Performance ran it out of gas on the dyno, and then of course the rod knock it had when it hit the dyno at TX2K3. There are also several others that have all experienced problems similar to these at Sound Performance.

I took my car there because they touted daily driveable supras that lasted and still do. My car has run for less than 4K miles in the last year and a half, and they have charged me over $20,000 just in the last year, bringing the total that I have spent with them to over $30,000. Now with a new motor costing me another $7,000 and the insincerity that they have shown, I have realized my mistakes in judgement and can only hope to pass on this information to unsuspectant consumers. Like any business, they are more than willing to take your money, as much as they can, but when they screw up your car, you will be left once again holding a bill. I have hundreds of instant messenger conversations saved in discussion over my car with them that show how things have been handled, and how they have tried to pass the blame on to Jason Siebels of AEM. The motor was built at Sound Performance, tuned at Sound Performance, and all the money I spent went to Sound Performance, so this rests in the hands of Sound Performance.


Free from defect? In good condition? Improperly installed and missing parts will lead to a no for the answer to these questions. Thorough and complete? Did I mention the pistons that they THOUGHT were of stock compression but failed to ever check even after the motor was built?


An act or process or manner of functioning or operating? I think I have clearly defined the results of the motor that was built for me by Sound Performance and how the car has run in the last year and a half, or more has NOT run.

It was agreed upon in July that Sound Performance would pay for the parts of my car since I decided to have Performance Motorsports rebuild the motor and fix previously done work, since the car had not run right in the entire time Sound Performance dealt with it. Since that time I have received some parts from Elmhurst Toyota that Sound Performance paid for and a small check in the amount of $500 in August, but unfortunately totalling nowhere near what the small part of my final bill they said they would pay. It is approaching the end of November now and after sending several emails and not getting any response nor receiving any checks and knowing they have received them, I have been encouraged by several in the Supra community to post my experiences. If Sound Performance rectifies this situation, then I will note it accordingly.

Hopefully you will learn from my tribulations and others where to go and not to go. Do you really want to go to a shop that lets you pay the bill when they screw up? After sending tens of thousands of dollars in business to Sound Performance through other customers, I will NEVER send another customer there and hope that you will never send another dollar to them.


BPU is so 1997
5,353 Posts
I know it's been an ongoing saga for you since I first met you two years ago, and I know you've thrown a buttload of money at the car and it's never ran correctly.

I've also always wondered about Ethan's car, I've yet to see one post from him saying his car was up and running correctly, seems like there is always something wrong with it. I just chose not to ask him about it since I know it's frustrating to spend so much money on something that doesn't move. :(

I heard one bad customer service issue from Kevin(V10EATR) when he tried to order a fuel system and was given the run around, but I figured I would still give them a try. When my front main seal went out, I tried to get some info on their new magical seal made by the NASCAR guy. That was about useless. Even when the guy wouldn't give me the time of day, I still attempted to pay $75 for a piece of plastic with a metal spring, and the guy wouldn't even take my order, and told me to call back and order it with Larry as he rushed me off the phone. I hung up, and called up Elmhurst instead, paid like $7 for the stock FMS and have had no problems yet.

How is the motor running now from PMS?

Bad Karma Supra
2,783 Posts
Ouch. Just like I said on the Big List - I thought i had bad luck. :(

Did PMS fix it up for ya?

5,062 Posts

Thanks for all the info........ suxs that you went through all that financially, and the entire headache itself. Just makes me wonder about certain supra shops....


457 Posts
Sorry about all your Supra problems. I hope your car is healthy soon. Thanks for sharing your story. The good the bad and the ugly, we always hear of the good and never of the bad and ugly. Thanks for the enlightenment.

GA Rocks!
1,094 Posts

i remember talking to u bud after the motor let go at tx2k3. you were in very good spirits considering what happened. It takes a lot of courage to post what you did. I know it must feel like a huge burden being lifted off your shoulders. If you feel this strongly about SP, you should have taken legal actions towards them before airing all of this out in the open.

I hope you and SP can rectify and come towards some kind of peaceful agreement.

Good luck,
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