AstroDan Posted July 14, 2010 Report Share Posted July 14, 2010 Guys: My SC seems to be putting out about 3lbs less of boost than it did a couple months ago. When I had the car dyno'd and until about May, I was seeing 10+ on the boost gauge. Now, it only gets to about 7. Also, there is a higher (really high, like 15000cps) "whine" than what I consider "normal". The car does not feel as quick either. It definitely does not put down 500whp now. All my fluid levels are correct, there is no other noises or any hesitation. It looks to me that all connections are where they belong and everything seems hooked up correctly. I'm at my wits end and hope the Yoda's in here might have an idea I can follow up on. Thanks in advance Dan Link to comment Share on other sites More sharing options...
pottydr Posted July 14, 2010 Report Share Posted July 14, 2010 Check your fuel pressure ? or change your fuel filter lately ? Guys: My SC seems to be putting out about 3lbs less of boost than it did a couple months ago. When I had the car dyno'd and until about May, I was seeing 10+ on the boost gauge. Now, it only gets to about 7. Also, there is a higher (really high, like 15000cps) "whine" than what I consider "normal". The car does not feel as quick either. It definitely does not put down 500whp now. All my fluid levels are correct, there is no other noises or any hesitation. It looks to me that all connections are where they belong and everything seems hooked up correctly. I'm at my wits end and hope the Yoda's in here might have an idea I can follow up on. Thanks in advance Dan Link to comment Share on other sites More sharing options...
blkGT500nCA Posted July 14, 2010 Report Share Posted July 14, 2010 +1 on the fuel filter. It's right below the drivers side door under the car. Maybe some data logging would be helpful too. Hope all is well Dan. Link to comment Share on other sites More sharing options...
AstroDan Posted July 14, 2010 Author Report Share Posted July 14, 2010 Thanks for the input, guys. The fuel filter is original. @ 12,500 miles. I don't think SAI changeed it when it was Whippled. I will check it and change if needed. The fuel pressure looks normal. As a side-note, I went to clean my air filter, (@ 5000 miles) but you have to disassemble practically the whole contraption so it will clear the fender. I still need to do that. All is well, Brian. Good to hear from you. Link to comment Share on other sites More sharing options...
RogerS Posted July 15, 2010 Report Share Posted July 15, 2010 Sounds like it could be belt slip Dan. You can contact Craig Robinson at craigr@shelbyamerican.com or call us at 702.943.7325 ext. 127 Roger Link to comment Share on other sites More sharing options...
CudaFly Posted July 15, 2010 Report Share Posted July 15, 2010 Agree with checking for belt slip. If you are looking for other mechanical problems I would also check for a vaccum leak and/or a bypass valve problem. Also consider that May average air temps versus July may be ~30 degrees hotter. That could easily account for ~1-2 psi loss and loss of power from higher intake air teperatures. My neighbor's modified GT500 pulled 90 rwhp less on the same dyno a summer day than a cool (45 degree) winter day, but it's running over 725 RWHP to begin with. Still that's about a 15% loss of power. So for a 500 RWHP car 15% would be about 75 RWHP loss . If you bring down your Intake Air Temps you will see a BIG difference in performace in hot weather (see these post): http://www.teamshelby.com/forums/index.php?/topic/42673-upgraded-radiator-and-heat-exchanger/page__view__findpost__p__700211 http://www.teamshelby.com/forums/index.php?/topic/39247-moroso-supercharger-tank-install/page__view__findpost__p__625993 Link to comment Share on other sites More sharing options...
AstroDan Posted July 15, 2010 Author Report Share Posted July 15, 2010 Sounds like it could be belt slip Dan. You can contact Craig Robinson at craigr@shelbyamerican.com or call us at 702.943.7325 ext. 127 Roger Thanks Roger. I will give you folks a holler tomorrow. Agree with checking for belt slip. If you are looking for other mechanical problems I would also check for a vaccum leak and/or a bypass valve problem. http://www.teamshelby.com/forums/index.php?/topic/42673-upgraded-radiator-and-heat-exchanger/page__view__findpost__p__700211 http://www.teamshelby.com/forums/index.php?/topic/39247-moroso-supercharger-tank-install/page__view__findpost__p__625993 Nice write-ups Brian. The exchanger looks like a sweet set-up, but kinda costly, no? Oh well...one more thing to add to the Shelby mod shop spring excursion! Dan Link to comment Share on other sites More sharing options...
Revan Racing Posted July 15, 2010 Report Share Posted July 15, 2010 Dan It is possible that you have belt slip as mentioned previously. Unless you've run C-16 Leaded Race Gas through the car it is most unlikely that your fuel filter is clogged especially with your fuel pressure remaining high which is measured post fuel filter at the fuel rail. Belt stretching and glazing therefore causing belt slip etc. is fairly common. It's good insurance to have an extra belt around anyway so I'd pick up a new belt and replace it and see if your problem is resolved. Ask any of the Shelby GT/SC guys that use the Shelby Heat Exchanger. You'll love it. Keep it on the future mod list for sure. Van Link to comment Share on other sites More sharing options...
AstroDan Posted July 15, 2010 Author Report Share Posted July 15, 2010 Dan It is possible that you have belt slip as mentioned previously. Unless you've run C-16 Leaded Race Gas through the car it is most unlikely that your fuel filter is clogged especially with your fuel pressure remaining high which is measured post fuel filter at the fuel rail. Belt stretching and glazing therefore causing belt slip etc. is fairly common. It's good insurance to have an extra belt around anyway so I'd pick up a new belt and replace it and see if your problem is resolved. Ask any of the Shelby GT/SC guys that use the Shelby Heat Exchanger. You'll love it. Keep it on the future mod list for sure. Van Thanks Van. I have never run racing fuel, so that probably removes the filter from contention. I'll still check it, but that's good to know. The HE system is definitely on the wish list... Dan Link to comment Share on other sites More sharing options...
COBRA SCOTTY Posted July 15, 2010 Report Share Posted July 15, 2010 Thanks Van. I have never run racing fuel, so that probably removes the filter from contention. I'll still check it, but that's good to know. The HE system is definitely on the wish list... Dan HEY DAN , SCOTTY HERE , SORRY TO HEAR YOUR HAVING A PROBLEM. BESIDES THE CHECK LIST THAT YOU HAVE FROM ALL OF THE OTHERS. THE TWIN FAN HEAT EXCHANGER I HAVE FROM SHELBY/REVAN RACING HAVE MADE A SIGNIFICANT DIFFERENCE IN THE HEAT SOAK AND BOOST MY CAR MAKES DURING THE WARM AND HOT WEATHER. IT WILL ALSO PROLONG PARTS AND ENGINE LIFE. GOOD LUCK WITH YOUR ISSUE AND IT IS MY GUESS YOU HAVE A GLAZED AND SLIPPING BELT. LOOKS LIKE IT'S TIME FOR AN NEW ONE. THAT IS THE 1ST PLACE I WOULD CHECK GIVEN YOUR SYMTOMS AND SOME OF THE BELT ISSUES THAT A FEW PEOPLE ARE HAVING WITH THE WHIPPLE 550 AND BECAUSE BELTS LIKE TO EXPAND , STRETCHING AND SLIP IN THE HOT WEATHER. OH ONE LAST THING ; DO NOT EVER USE BELT DRESSING ON YOUR S/C OR OTHER BELTS. IT IS ONLY A SHORT TERM FIX ; IF AT ALL AND ONLY WORKS PART OF THE TIME AND WILL EVENTUALLY DAMAGE THE BELTS BY CAUSING GLAZING , DRY ROTTING AND CRACKING. B.O.L. SCOTTY Link to comment Share on other sites More sharing options...
AstroDan Posted July 15, 2010 Author Report Share Posted July 15, 2010 This Forum is great! A lot of good paths to follow here. I e-mailed and got a response from Craig at Shelby. I will take her out after work this afternoon and double-check my fuel pressure at WOT. More to come, and thanks for all the great input Folks. Link to comment Share on other sites More sharing options...
AstroDan Posted July 16, 2010 Author Report Share Posted July 16, 2010 OK. I made a few WOT runs in 2nd, then 3rd gear down Grizzly Island Road. As you can see in the vids, it looks like @7.5# boost and maybe 65# fuel. I think its worth noting on the 1st run, I hit the rev limiter and the fuel pressure hits about 80+, but the rest were pretty uniform. Also in the 1st vid is the engine, SC at idle...The 2nd vid is from September last year on the road to Sears Point for a 1/4 mile run. I was taunting my Corvette buddy, Javier and you can see the 10# boost and interestingly (only) about 60# fuel. If you listen closely, especially the last couple (1st vid), you can hear the extra high whine I noted earlier. To me the belt looks good. What do you folks think? I'm gonna stop thinking about this for a while and enjoy my Custom Elite... Dan Link to comment Share on other sites More sharing options...
blkGT500nCA Posted July 16, 2010 Report Share Posted July 16, 2010 Beautiful guitars!!! Link to comment Share on other sites More sharing options...
vapor08GT500 Posted July 16, 2010 Report Share Posted July 16, 2010 Beautiful guitars!!! Like Van said, heat has an effect on boost, as does belt glazing and slippage.... Alex Link to comment Share on other sites More sharing options...
slbgtsc Posted July 16, 2010 Report Share Posted July 16, 2010 Have you tried reloading your program? or disconnecting the battery for 15 minutes to let the program re-set. Link to comment Share on other sites More sharing options...
ShowCar Posted July 16, 2010 Report Share Posted July 16, 2010 In the month of May I saw 11-12lbs. of boost and ran 12.0's@118mph all day long. Now in July in 90 degree temps my boost level never goes above 9lbs and I run 12.3@114mph. The power and boost falls off in the heat. I drive my car everyday and it runs fine just slower in the heat. From the vids the numbers look fine along with the belt. It could all be temperture related. From what Ive learned the FRPP tune is very conservative and takes alot way in the heat. You might just be seeing normal things going on. I would still change maintance items because they are probably due anyway. Good luck. Link to comment Share on other sites More sharing options...
Blown Away Posted July 16, 2010 Report Share Posted July 16, 2010 I would probably attribute it to the heat. I just took my car out for a drive (in miserable heat) and where the boost is usually 9lbs. at wot, it is now at 7. I'm not an expert, just giving you my perspective and experiences from today. Hopefully that is what your problem is. Dan Link to comment Share on other sites More sharing options...
tyler2118 Posted August 4, 2010 Report Share Posted August 4, 2010 Yup its heat doesn't look like any dust from slip. im about 11 lbs in winter and 9 in summer. Link to comment Share on other sites More sharing options...
AstroDan Posted September 16, 2010 Author Report Share Posted September 16, 2010 Well, I now have the "smoking gun"! I took Betsy over to Walnut Creek Ford yesterday and the excellent staff there figured out my problem. Thanks Vince, Dan and Sean! It seems the gasket between the blower and the intake is bad and that is where the loss is coming from. They have ordered the replacement and I'll bring her in and they'll swap out the BO gasket. I am so glad it turns out to be something as simple as this. I will leave my camera with Sean when he does the work to take a couple shots. I also asked to try to get clarification as to why this happened. I will post up with follow-up info to share with all. I miss my beast and it'll be great ot get her back! More to come... Dan Link to comment Share on other sites More sharing options...
07SGT4578 Posted September 16, 2010 Report Share Posted September 16, 2010 I bet that is where the rush of air was coming from, that Rick found. Link to comment Share on other sites More sharing options...
AstroDan Posted September 16, 2010 Author Report Share Posted September 16, 2010 I bet that is where the rush of air was coming from, that Rick found. Maybe. He thought it might be at the joint between the back of the blower and the air intake. I could not feel anything there, myself. More to come... Link to comment Share on other sites More sharing options...
AstroDan Posted September 24, 2010 Author Report Share Posted September 24, 2010 Well, she's perfect again! I had the gasket changed out yesterday at Walnut Creek Ford. Betsy now has 10 lbs boost again and the sound is back to sweetness again. If this happens again, I will do the swap myself. Shawn took a couple pictures that I will post up if there is interest here. Since traffic was very heavy on the ride home, I drove her in to work today in the "Friday-light" Bay Area traffic this morning...Delightful. Dan Link to comment Share on other sites More sharing options...
COBRA SCOTTY Posted September 24, 2010 Report Share Posted September 24, 2010 CONGRATS ON FINDING YOUR LEAK. NOW IT'S AS GOOD AS NEW. ENJOY !!!! :happy feet: :happy feet: :happy feet: SCOTTY Link to comment Share on other sites More sharing options...
07-2937 Posted September 24, 2010 Report Share Posted September 24, 2010 Awesome!!!!! Link to comment Share on other sites More sharing options...
SVT NAJA Posted September 25, 2010 Report Share Posted September 25, 2010 Well, she's perfect again! I had the gasket changed out yesterday at Walnut Creek Ford. Betsy now has 10 lbs boost again and the sound is back to sweetness again. If this happens again, I will do the swap myself. Shawn took a couple pictures that I will post up if there is interest here. Since traffic was very heavy on the ride home, I drove her in to work today in the "Friday-light" Bay Area traffic this morning...Delightful. Dan Dan, Great to hear you got the problem resolved and that Betsy is breathing heavy again. Now it's time for another "mixed" run! Link to comment Share on other sites More sharing options...
ilmor Posted September 25, 2010 Report Share Posted September 25, 2010 Its always interesting to read through threads like this to see how the issues were resolved. Link to comment Share on other sites More sharing options...
JeffIsHereToo Posted September 25, 2010 Report Share Posted September 25, 2010 Its always interesting to read through threads like this to see how the issues were resolved. +1 :happy feet: Link to comment Share on other sites More sharing options...
blkGT500nCA Posted September 25, 2010 Report Share Posted September 25, 2010 Glad she's all fixed up Dan! Link to comment Share on other sites More sharing options...
AstroDan Posted September 26, 2010 Author Report Share Posted September 26, 2010 Thanks guys. The old gasket, that I kept, looked to have a small tear in the area around the drivers side, rear near the TBS. The gasket material looks like a Durabla-type material, which I can make myself to save the ~$40... Hector talked about one more mixed run before the season's over, Jim and Brian. I'm in. Dan Link to comment Share on other sites More sharing options...
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