garrell.770 Posted January 13, 2014 Report Share Posted January 13, 2014 Let me set the situation up as short as I can. Two years ago I started running my now 52,000 mile 03 SSS on airport runways in a one mile standing start and the speeds progressed as: Sept. 2010 completely stock 3 runs around 123.5 MPH. Oct. of 2010 after a K&N CAI and tweaking with a Hypertech Tuner speeds were around 126. April 2011 1:8 to 1:00 roller rockers and Bee-Hive valve springs, ported stock throttle body, Tonno cover and a HP tuneup speeds stepped up to 133 to almost 135 MPH and during this time I broke or established three landspeed records. Last summer I got really serious and after much research I told my speed shop what I wanted. I asked for a Comp Cams kit Cam and lifters that the peak HP range would be 2,500 to 6,000 RPM, BBK Short tube headers with Doug's Headers electric cutouts. Then after much thinking and researching I added a LSXrt intake and a retune. My shop doesn't have a dyno to accommodate an all wheel drive truck. I made four runs on the Ohio, Mile last Sept. and I was hoping to maybe run 140 MPH but at least certainly 138. To my shock I ran 130.20, 130.83 etc. The truck roared off the line and seemed to pull harder than it ever had, no stumbling, popping bogging and six people came up to me and comment on how fast the truck ran and wanted to know what my speeds were. On the last run I glanced down to the tach and the truck shifted from low to second at 6,200 RPM then fell back to 4,000 RPM and was almost the speed traps before it reached 6,200 RPM'S again and shifted to 3RD gear where it fell to 4,000 RPM'S and fell flat on it 's face. I know the tuneup would be suspect but I do not have access to anyone with a dyno that would work with an all wheel drive of the length of my truck and the truck ran great. I am wondering about the torque converter which is the stock converter or even the transmission line pressure. I did ask for on the tuneup to increase the shifts by 50% which was done through the laptop and not internally. Now you can rip into me and tell me where I went wrong, Thanks Quote Link to comment Share on other sites More sharing options...
shawnss Posted January 13, 2014 Report Share Posted January 13, 2014 Do you know any of the specs on the cam that was used? Quote Link to comment Share on other sites More sharing options...
garrell.770 Posted January 13, 2014 Author Report Share Posted January 13, 2014 I have the booklet and I just about wore it out studying it now I can't find it. I am going to search everywhere in the house and shop that it can be this morning where I can post the stats. I also have my old cam in the box that the new cam came in so if you will when you are in the forum watch for the cam info. Quote Link to comment Share on other sites More sharing options...
GI.SS Posted January 13, 2014 Report Share Posted January 13, 2014 if you have the box, comp slaps a sticker on the side with the specs. has the fuel filter ever been replaced? some dont know the 03 has an inline filter on the rail. hard to say why its doing what its doing, we would need to see the tune. Im guessing parameters are off. BUT i know iv had mine over 140 via gps and shifting into 3rd always feel very sluggish compared to the other gears. But switching your shorties out for a 1 7/8" primary long tube would be best for what your using the truck for. Quote Link to comment Share on other sites More sharing options...
garrell.770 Posted January 13, 2014 Author Report Share Posted January 13, 2014 Found the packet with the cam info:Comp Cams part # 54-452-11 . :GM G3 XFI 266 HR15 Gross valve lift:'Intake .520, Exhaust .524 Duration @ .006 Tappet Lift, Intake 266, Exhaust .524 Specs are for cam installed @ 111.0Intake Center Line, Duration @ .050 Intake 212, Exhaust 216 Lobe Lift: Intake .3060, Exhaust .3080 Lobe Separation 115 The Valve springs and lifters were installed as part of a kit or recommendations from Comp Cams. I reused my ported 92 MM throttle body with an adapter and new fuel rails. The engine revs to about 2,000 RPM 'S when cranked but then drops back down to an idle of around 900 RPM'S. The engine never bogs, stalls or hesitates in anyway. We checked for a vacuum leak everywhere but none were found. With the headers, cutouts open, cam change and the LSXrt intake change we conservatively estimated maybe 75 flywheel horsepower. The speed shop had installed many of these same cams in late model Corvettes and Camaros which dynoed around 45 rear wheel HP. Remember I used the stock converter. The truck seems to not run as strong around locally traffic light to traffic light. This truck is a heavy weight at around 6,000 lbs. with me in it, could I have given up torque for horsepower and that is a lot of weight to get moving. I take the truck to the dragstrip about four times a year and the last time out I ran which was before the cam and intake change I ran 9.08, 9.13, 8.94 which if I remember correctly converted to around 13.90 in 1/4 mile and I don't think it will do that now. That îs all I can think of so please HELP!!! Quote Link to comment Share on other sites More sharing options...
garrell.770 Posted January 13, 2014 Author Report Share Posted January 13, 2014 Found the packet with the cam info:Comp Cams part # 54-452-11 . :GM G3 XFI 266 HR15 Gross valve lift:'Intake .520, Exhaust .524 Duration @ .006 Tappet Lift, Intake 266, Exhaust .524 Specs are for cam installed @ 111.0Intake Center Line, Duration @ .050 Intake 212, Exhaust 216 Lobe Lift: Intake .3060, Exhaust .3080 Lobe Separation 115 The Valve springs and lifters were installed as part of a kit or recommendations from Comp Cams. I reused my ported 92 MM throttle body with an adapter and new fuel rails. The engine revs to about 2,000 RPM 'S when cranked but then drops back down to an idle of around 900 RPM'S. The engine never bogs, stalls or hesitates in anyway. We checked for a vacuum leak everywhere but none were found. With the headers, cutouts open, cam change and the LSXrt intake change we conservatively estimated maybe 75 flywheel horsepower. The speed shop had installed many of these same cams in late model Corvettes and Camaros which dynoed around 45 rear wheel HP. Remember I used the stock converter. The truck seems to not run as strong around locally traffic light to traffic light. This truck is a heavy weight at around 6,000 lbs. with me in it, could I have given up torque for horsepower and that is a lot of weight to get moving. I take the truck to the dragstrip about four times a year and the last time out I ran which was before the cam and intake change I ran 9.08, 9.13, 8.94 which if I remember correctly converted to around 13.90 in 1/4 mile and I don't think it will do that now. That îs all I can think of so please HELP!!! Quote Link to comment Share on other sites More sharing options...
AugustBurnsRed19 Posted January 13, 2014 Report Share Posted January 13, 2014 What size roller rockers did you get installed again? The Cam seems small if it kicks out at 6000rpms don't be afraid of a decent sized Cam the motor can handle some rpms at least up to 6800 or maybe even 7200 Quote Link to comment Share on other sites More sharing options...
AugustBurnsRed19 Posted January 13, 2014 Report Share Posted January 13, 2014 Definitely gonna want to get some long tube headers maybe pacesetter ceramics? And if you don't already some hardened push rods Quote Link to comment Share on other sites More sharing options...
garrell.770 Posted January 13, 2014 Author Report Share Posted January 13, 2014 I know the fuel filter has probably not been changed but even with the short tubes and the cut outs open then the cam change and intake I can't understand losing around 5 MPH instead of gaining speed. Before the last mods were performed when I ran 134 and change I think the truck would have ran 138 in a mile and one half because the engine is far from being maxed out in one mile. When racing for top speed in a mile you are just waved off, reaction time is not important but getting up to speed is. I hold the break and leave at about 1,800 to 2,000 RPM'S so could using the stock converter be involved in the problem. I will go to a Show N Go in April to drag race so I wonder if I change the fuel filter and put a 2500 stall converter would I possibly see an improvement. I know I am rambling but I am throwing out thoughts as they come to me. Would the engine be getting adequate. Air using the stock ported throttle body instead of the 102 mm that the intake was designed for, I called the Mfgr. Before doing this and they said that using their adapter that it should not hurt the performance. If I could back time up two years I would have installed headers and a super charger and I have spent almost enough to have payed for it. Still open to all your suggestions and opinions and thanks for the help so far, Garrell Quote Link to comment Share on other sites More sharing options...
canadianVRss Posted January 13, 2014 Report Share Posted January 13, 2014 You need a converter, although that is a small cam, a converter will get you going a lot faster. That cam seems to be a boost cam, post the BTDC ATDC BBDC ATDC numbers and check overlap. Also, your shift points are low. 6400 1st to second will get you into a little higher RPMs for 2nd gear, a converter will also help out with this. Quote Link to comment Share on other sites More sharing options...
GI.SS Posted January 13, 2014 Report Share Posted January 13, 2014 A trailblazer i6 converter should do the trick Quote Link to comment Share on other sites More sharing options...
AugustBurnsRed19 Posted January 13, 2014 Report Share Posted January 13, 2014 (edited) Dude get a stall with a nice lock up clutch youre not racing from a dig so you dont need a 3600 stall thats what I got and im telling you that thing is badass! don't go with a 78 or 87mm throttle body at least get a 90mm off of a ls3. You are definitely going to want some bigger injectors maybe 42lbs or 40lb injectors would be good. Also last but not least the things that will help top end the most are gonna be cam and heads. You're cam seems too small for top end man maybe get cam that has a power band of 2000rpm-7200rpms your shift points don't necessarily have to shift at 7200rpms. Edited January 13, 2014 by AugustBurnsRed19 (see edit history) Quote Link to comment Share on other sites More sharing options...
JC03SS Posted January 14, 2014 Report Share Posted January 14, 2014 If I'm not mistaken you have certain guide lines you have to stay within correct? Quote Link to comment Share on other sites More sharing options...
AugustBurnsRed19 Posted January 14, 2014 Report Share Posted January 14, 2014 I'm telling you man that cam is way too small that's the problem. Get like something within the range of duration @ .5: 228 240 Lift: 580 625 pick a nice cam that measures in between there. Don't get a huge lope either I wouldn't go above 114 pick something between 111 and 114 lope. Or get like a Torquer v cam I hear they have some nice top end for all motor purposes. I'm not a Cam expert lol but the problem is your cam is too small! Get some bigger injectors with all that air 102mm intake and 90mm throttle body you will need more fuel. Also need more fuel when you get bigger cam! Injectors! 40lbs or bigger I wouldn't go bigger than 50lbs thats just me all your gas mileage is in the tune! Quote Link to comment Share on other sites More sharing options...
GI.SS Posted January 14, 2014 Report Share Posted January 14, 2014 I'm telling you man that cam is way too small that's the problem. Get like something within the range of duration @ .5: 228 240 Lift: 580 625 pick a nice cam that measures in between there. Don't get a huge lope either I wouldn't go above 114 pick something between 111 and 114 lope. Or get like a Torquer v cam I hear they have some nice top end for all motor purposes. I'm not a Cam expert lol but the problem is your cam is too small! Get some bigger injectors with all that air 102mm intake and 90mm throttle body you will need more fuel. Also need more fuel when you get bigger cam! Injectors! 40lbs or bigger I wouldn't go bigger than 50lbs thats just me all your gas mileage is in the tune! there is some mis-information here...... but anyway, does the class you race have guidelines? rules? if its unlimited, how far do you want to take it? what are you looking to spend? you not reaching 140mph is a little strange IMO when you say it fell flat on its face in the 130mph range, can you describe it any better? I bet its in your tune, also converter. Quote Link to comment Share on other sites More sharing options...
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