But I wouldn't drive it at all til you can confirm the a/f ratio on a dyno.
Bad day at the track, again!
Thread Starter
Melting Slicks
Joined: Dec 2004
Posts: 2,137
Likes: 5
From: Howard PA
Originally Posted by lcvette
have you checked anything since your last post about power being down? your MPH is nto even close to where it should be. my stock paper filtered street tired lt4 ran 109mph in the 1/4 and 13.19 with half assed 60's of 1.9. this is not fibbed or exagerated it was BONE STOCK! ac delco paper filter element and dirty at that.
there is something just not right with your engine. something you are overlooking. there has to be. with the hot cam in there you should be revving to around 6300rpm for shifts.. your pmaking power or should be making power to 6100rpm.
whats your fuel pressure set at? you may have a bad injector, have you checked your timing set yet? something is just plain missed here thats all there is to it. you should be in the 112-114mph zone, no bull**** nor excuses, that what your setup should be running. go through everything you have done over and over until you find it. or you are not getting your moneys worth from your car.
I will be more then happy to help anyway that I can, PM me questions or anything you may think of that you were NOT sure about when modding. somewhere thee in lies the answer. 105mph with a **** poor driver is low, not saying you are **** poor, but the MPH has not much to do with launch or shifting (provided you can shift decently quick and not roll 30 feet between gear changes) your problem is driving me crazy.. are you SURE you put a hot cam in it and not a stock LT1 cam? ya never know! check it.. not hard to mix cams up, not you necessarily but maybe if it was purchased used.. someone may have miss boxed it.
Chris
there is something just not right with your engine. something you are overlooking. there has to be. with the hot cam in there you should be revving to around 6300rpm for shifts.. your pmaking power or should be making power to 6100rpm.
whats your fuel pressure set at? you may have a bad injector, have you checked your timing set yet? something is just plain missed here thats all there is to it. you should be in the 112-114mph zone, no bull**** nor excuses, that what your setup should be running. go through everything you have done over and over until you find it. or you are not getting your moneys worth from your car.
I will be more then happy to help anyway that I can, PM me questions or anything you may think of that you were NOT sure about when modding. somewhere thee in lies the answer. 105mph with a **** poor driver is low, not saying you are **** poor, but the MPH has not much to do with launch or shifting (provided you can shift decently quick and not roll 30 feet between gear changes) your problem is driving me crazy.. are you SURE you put a hot cam in it and not a stock LT1 cam? ya never know! check it.. not hard to mix cams up, not you necessarily but maybe if it was purchased used.. someone may have miss boxed it.
Chris
Let's not get all worked up here, it'll get sorted out, I'm supposed to be the one throwing a fit here, geeze.
There is this one thing I do ponder but I can't do anything about until I see a tuner on the dyno. I'm starting to wonder about the injectors, they have 90,000 on them. The plugs are new, the wires are new, so there shouldn't be any problem there. The car runs ten times better than it did when stock, my driving is the biggest problem with ETs I'm sure of it.
I'm sure I received a Hot Cam, got it from Summit in a nice tubular shipping container with a GM label on it. The car has a well defined lope to it. Stock cams don't do that. You can tell it's having a hard time breathing through the stock exhaust, I'll post a video tomorrow.
I'm really starting to think also that with all this air going in it's doing some harm as well as good, sounds crazy I know. It's just not going out.
If the dyno doesn't yield any answers I'll tear it down and degree the cam, however it is installed correctly, not my fist rodeo there.
I shouldn't have posted that video, it's a real example of how not to shift.
Melting Slicks
Joined: Jun 1999
Posts: 2,872
Likes: 3
From: Wilmington NC
thats a good idea.. I would change the fuel filter, pull the pump out of the tanka nd replace the filter sock check the tank for sediment and debris. look at getting some 30lb injectors from FMS for the tune If money is available.. that way you can put your fuel system to rest with exception of the fuel pressure regulator.. by the way is it stock? if so maybe replace it too while your at it.. these things are mods anyways and eventually you will be glad you did it! that way Alvin can pop the new injector flow rates in while at the dyno. and these are VERY easy to swap out as you know. do the injectors and the AFPR same time knock it out in about 30 minutes. the fuel filter if its never been changed could be a culprit too. and alot of people avoid the filter sock in the tank.. mine was destroyed at 104k it had come apart and the pump had swallowed a few fibers from it.. good idea to R&R these all at the same time on a high milage motor as yours. your ignition sounds new so then there ya go you have addressed and modded the supporting systems and can rest easier!
I know.. LT4's are near and dear to my heart, I just want all of them to run like scalded dogs...lol and I like for the owners to know how well they can run.. like I said.. it is a whole new world when your knocking on 11's door and trapping mid 11teens... Just wanna see the post where it happens for ya!
Chris
I know.. LT4's are near and dear to my heart, I just want all of them to run like scalded dogs...lol and I like for the owners to know how well they can run.. like I said.. it is a whole new world when your knocking on 11's door and trapping mid 11teens... Just wanna see the post where it happens for ya!
Chris
Racer
Joined: Apr 2004
Posts: 487
Likes: 0
From: Huntsville AL
I would quit racing it til you get things worked out. I trap 88mph in the 8th and you know my mods. The only ones that really count are my headers and TB. You should be trapping much higher than what you are. Get your car on some scales too, mine weighs 3200.
Safety Car
Joined: Sep 2002
Posts: 4,030
Likes: 6
From: Maryland
Originally Posted by ALLT4
I don't know what's going on, this car should be quicker than this. 391CE
LT4, HotCam, Heads ported and polished, new springs, gasket matched.
Excuses... no tune, full tank, and I mean tippy top, with spare, streets, and through the completely stock exhaust.
http://www.personal.psu.edu/gls17/MOV00938.MPG Might need to "save as" slow server.
LT4, HotCam, Heads ported and polished, new springs, gasket matched.
Excuses... no tune, full tank, and I mean tippy top, with spare, streets, and through the completely stock exhaust.
http://www.personal.psu.edu/gls17/MOV00938.MPG Might need to "save as" slow server.
My 6spd LT1 with ported heads, mild cam (214/224@050, .566" lift) 1.6 rr's, all stock exhaust in 2003 ran 13.0 @ 109-110. (w/spare tire but 1/2 tank fuel) But this was after practice! It took me 5-10 passes to get used to the much higher revving motor--this could be your problem. Try some more practice.
Otherwise--I immediatly ran 12.7's @114mph just by going to muffler elims instead of the can mufflers. Still stock headers.
I eventually got 12.55's @114.9 mph with a full PE exhaust. Still stock headers.
All times above were run with street tires--the 12.7, 12.55 were aided by F1 Supercar street tires, much better than GSC's.
You have to keep the engine cool to get these times, too--launch at 170 oil temp. I don't bother to run on a hot engine if I want to get a decent time.
Last edited by sothpaw2; Aug 21, 2006 at 12:00 PM.
Melting Slicks
Joined: Mar 2003
Posts: 2,472
Likes: 0
From: Toronto ONTARIO
Originally Posted by lcvette
have you checked anything since your last post about power being down? your MPH is nto even close to where it should be. my stock paper filtered street tired lt4 ran 109mph in the 1/4 and 13.19 with half assed 60's of 1.9. this is not fibbed or exagerated it was BONE STOCK! ac delco paper filter element and dirty at that.
there is something just not right with your engine. something you are overlooking. there has to be. with the hot cam in there you should be revving to around 6300rpm for shifts.. your pmaking power or should be making power to 6100rpm.
whats your fuel pressure set at? you may have a bad injector, have you checked your timing set yet? something is just plain missed here thats all there is to it. you should be in the 112-114mph zone, no bull**** nor excuses, that what your setup should be running. go through everything you have done over and over until you find it. or you are not getting your moneys worth from your car.
I will be more then happy to help anyway that I can, PM me questions or anything you may think of that you were NOT sure about when modding. somewhere thee in lies the answer. 105mph with a **** poor driver is low, not saying you are **** poor, but the MPH has not much to do with launch or shifting (provided you can shift decently quick and not roll 30 feet between gear changes) your problem is driving me crazy.. are you SURE you put a hot cam in it and not a stock LT1 cam? ya never know! check it.. not hard to mix cams up, not you necessarily but maybe if it was purchased used.. someone may have miss boxed it.
Chris
there is something just not right with your engine. something you are overlooking. there has to be. with the hot cam in there you should be revving to around 6300rpm for shifts.. your pmaking power or should be making power to 6100rpm.
whats your fuel pressure set at? you may have a bad injector, have you checked your timing set yet? something is just plain missed here thats all there is to it. you should be in the 112-114mph zone, no bull**** nor excuses, that what your setup should be running. go through everything you have done over and over until you find it. or you are not getting your moneys worth from your car.
I will be more then happy to help anyway that I can, PM me questions or anything you may think of that you were NOT sure about when modding. somewhere thee in lies the answer. 105mph with a **** poor driver is low, not saying you are **** poor, but the MPH has not much to do with launch or shifting (provided you can shift decently quick and not roll 30 feet between gear changes) your problem is driving me crazy.. are you SURE you put a hot cam in it and not a stock LT1 cam? ya never know! check it.. not hard to mix cams up, not you necessarily but maybe if it was purchased used.. someone may have miss boxed it.
Chris
Couldn't have said it better. SOmething is CLEARLY wrong. Were the mods listed the only ones on the car? What rpm are you shifting at ? Is your car tuned ?
i think someone misguessing your car on the timeslip as the one on the left tells you something about what #s you should be running
Thread Starter
Melting Slicks
Joined: Dec 2004
Posts: 2,137
Likes: 5
From: Howard PA
It's just more to show that it isn't a stock LT1 cam...and there's nothing wrong with the way it's running, except ET wise that is.
Originally Posted by lcvette
are you SURE you put a hot cam in it and not a stock LT1 cam?
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Burning Brakes
Joined: Nov 2004
Posts: 800
Likes: 3
From: Port Orange FL
I would definitely get a tune. After I did a mild cam/heads on my LT1 I was fairly dissapointed in the initial result. On the dyno it made 268 RWHP. After a few dyno runs and a tune it made 328 RWHP. 
Roy
Roy
Drifting
Joined: Feb 2004
Posts: 1,277
Likes: 1
From: Santa Maria CA
My pontiac 455 in my LeMans has factory manifolds and runs 12.0's@112mph with all its goodies. No reason stock manifolds are the culprit. Yes they do choke but they aren't the reason the car runs 105mph traps. Don't go buying headers thinkin' its the reason your car isn't running up to par with everyone else.
I believe a possible clogged cat or both are whats slowing you down. I don't know your cars history like many of us so its just an guess from experience.
I believe a possible clogged cat or both are whats slowing you down. I don't know your cars history like many of us so its just an guess from experience.
Le Mans Master
Joined: Apr 2000
Posts: 5,713
Likes: 105
From: Manassas VA
ALLT4, This may have been ask of you before, but did you buy the hotcam from a GM dealer or possibably off of ebay. I heard there were some knock offs on ebay that were not the same specs.
Thread Starter
Melting Slicks
Joined: Dec 2004
Posts: 2,137
Likes: 5
From: Howard PA
Originally Posted by 93 ragtop
ALLT4, This may have been ask of you before, but did you buy the hotcam from a GM dealer or possibably off of ebay. I heard there were some knock offs on ebay that were not the same specs.
Originally Posted by ALLT4
I'm sure I received a Hot Cam, got it from Summit in a nice tubular shipping container with a GM label on it. The car has a well defined lope to it. Stock cams don't do that. You can tell it's having a hard time breathing through the stock exhaust, I'll post a video tomorrow.
The gas tank was full, the spare is questionable as to whether folks post slips without it or not, the driver is questionable at best, the 60' times aren't anything to write home about, the tires suck, the engine temps were in the 200's
I need numbers at this point to go on before I start doubting anything I did or the cars performance. Only then will I decide which route to go.
Last edited by ALLT4; Aug 21, 2006 at 11:05 PM.
Thread Starter
Melting Slicks
Joined: Dec 2004
Posts: 2,137
Likes: 5
From: Howard PA
Hey Mojo, I'd probably lock this one down and have folks follow the thread below.
http://forums.corvetteforum.com/show....php?t=1477478
http://forums.corvetteforum.com/show....php?t=1477478
Last edited by ALLT4; Aug 23, 2006 at 07:06 PM.