newschool72

iTrader: (12)

As a simple ,quick test ,I would up the time down low. You said it just walks out to 30-40 ft? I wonder if that is where the tach gets to 3K when the timing goes all in. Try 34 all in by 2K. I bet the 60 ft will improve, maybe enough to touch the 13s. Next thing, get a good set of headers! All LS engines love to move air. Get more in, get more out. Air pump basics 101. 5800rpms seems a little low and springs will help, like others have said, but I thing the exhaust will help that out too. 2.25" exhaust and manifolds might not move enough air for more than 5800. It could be an air wall, free it up.

jgillen91

iTrader: (1)

Verify you are indeed getting wide open throttle with you throttle linkage. I've been there went from a 12.2 sec 1/4 mile to 10.90 1/4 lol

cruisin'73

iTrader: (8)

BeeterOlds I am right there with you, just a little disappointed with my first round of 1/4 mile times. Maybe sharing data will help us both out

EDIT: Forgot car details

1973 Nova
3500LB including 260LB driver
Mild performance rebuild TH350
2200 stall convertor
Open 2.90:1 rear end
245 BF Goodrich Radial T/As

Engine:
-Junkyard '03 5.3 with 80K-COMPLETELY STOCK
-Good consistent compression in all holes
-Rebuilt Demon 750, still in tuning stages
-Edelbrock dual plane
-MSD 6010 18° initial, 34° all in at 4000
-Ebay SS 4th gen F-body headers, 2 ¾ primary, 3” collectors
-Dual 3” to Thrush mufflers dumped at axle
-Stock truck coils/wires
-New NGK TR55 plugs

Performance:
Elapsed Times: 15.1sec, 14.6sec, 14.3sec
60” times: 2.4 sec, 2.7sec, 2.25sec
Trap Speeds: 96.4 MPH, 94.6MPH, 94.06MPH (and 99.7MPH on an old fashion flag drop race)



*Disclaimer* This was my first time at a track in 10 years so I was pretty rusty. Hence the constant improvement.

Comparing my 14.3 to your 14.1, I would really expect a little more from your LS1 cam, M/T tires and 3.73 rear gears.

I am in for details and results so best of luck and keep us posted!

toxic99

Alot of YOUR issue seems to be getting back into the groove of things lol...judging by all the imroved drastically time slips as you went. Also, lose the thrush mufflers, thats 3 tenths right there imo... You need to bring your total timing all in sooner if not a lil more at lower rpm and taper off, will help with down low rpm torque. You didnt say if you had a stall so, if not, get 3000 at minimum...

toxic99

OP, agreed on the valave spring swap. Stock ls1 or truck springs will most likely float early as stated, with 100k miles on them, that is. New, they shouldnt but how many 100k mile motors come with fresh springs lol...Would also ditch the quadro at the track imo, try a 650 dbp atleast or a 750 if you can get your hands on one. Stock mainfolds and the small exhaust will also hold you back. Last but certainly not least, get an aftermarket stall, 3000k plus. Maybe ask speedtigger what he's running, seems to be working in his car, as he has a 2004r as well.

cruisin'73

iTrader: (8)

Toxic99: Thanks for pointing out that I omitted car info, kind of important to the conversation.

You are right on with the driver being the biggest holdback! I probably have quite a bit more to gain from further experience!

Interesting recommendation on the Thrush, do you think they are really costing 3/10th! Worth a try. +removing the pipes nad mufflers is probably 60LB!

BeeterOlds, I bet both of us could benefit from upgrading to fresh springs, or better yet some PAC1218s. Also I have seen several threads with guys experiencing power loss and engine misses above 6000RPM due to bad + or – to the MSD 6010/6012 box. Seems to cause spark scatter or missed spark entirely. Might be worth looking into…

newschool72

iTrader: (12)

With a stock 5.3 and 3" exhaust, I don't think you have the same issues as the OP on getting the old air out. I would doubt you would see any improvement with exhaust work. In fact ,you may loose a little TQ by freeing up your exhaust.
The OP ,on the other hand, is severely restricted with stock manifolds and a 2.25" system. If it were me, I would go to a 2 1/2" system w good flowing mufflers AND 1 3/4" long tube headers, set the timing to be all in by 2K and go back for some almost guaranteed 13 sec time slips. And unless you are a good quadrabogg tuner or know one, slap a 4150 on it and get to tuning.
I run a 2004R and ran 12.15 ( but with a mild LS3) with a 2100 stall D5 12" converter, but you will see a great gain with a looser converter. I just installed a 2800 stall ( I think that is the same stall speed Tigger is using too) but haven't been back to the track to test yet. Do you plan to go bigger soon on the cam? If so I would wait on the converter till you know what the other cam wants. If you are going to stay with the current setup, I would stall according to what you plan to do with the car "most of the time". Even a 3K stall would show a huge improvement and keep it street friendly. If it is a drag car most of the time ,even with a stock cam, you should see a good improvement with something in the 3600-4000rpm stall range. Good Luck! and keep us posted

fast89stang

iTrader: (2)

Did I see 4.5 fuel pressure? Might be a little low there too. I would want at least 6 psi.

fast89stang

iTrader: (2)

I would bet you would pick up alot going with a double pumper carb. The vac secondaries of the quadrajunk wont come on very quick unless its had some work done.

ZONES89RS

iTrader: (25)

I had 4.5 psi with my 6.0 spinning 7100 at the 1/8th mile, when I uppers to 6.5 I picked up nothing. In the 1/4 I may have noticed but he should be at 6 points but he will not gain anything but its worth trying.

Beeterolds

I appreciate the insight from everyone.. but im going to be blunt when I say I am not ditching the Q-jet.. I know how to tune these carbs and mine performs flawlessly.. Even though a Holley might be a better choice in regards of tuning abilities.. There is nothing wrong with this carb..

I can't blame the Q for my lack of a decent time because its a known fact im running worn springs.. so those are on the list to be swapped out and I already have headers in the mail... I also I have to fine tune my timing curve a bit more before I really want to throw parts at it..

I cranked up the fuel pressure one a couple passes and nothing changed..

So.. I think im going to toss on a set of headers, change the springs and fart around with the timing curve and see what happens..

ZONES89RS

iTrader: (25)

let us know!

As for the carb, I was saying to try it for the heck of it if you have a friend with something you can use. Not buy one.

fast89stang

iTrader: (2)

I know my 302 wouldnt even run on fuel pressure that low. I was running 6.8s tho. I am pretty sure this 6.0 of mine wouldnt run with it that low either. Some people can tune quadrajets good, and they work well, when they work. BUT, like zone said, if you could borrow one, i bet you would pick up a decent bit.

newschool72

iTrader: (12)

If you like the Qjet, say with it by all means. If it works for you, it works. I think that a timing change and freeing the exhaust will get you to your goal. Now Im going to pop some corn and wait for results!

Pop N Wood

iTrader: (1)

LOL. I didn't think anyone was going to be able to talk him out of that Q jet.

Rock on, my brother!

I ran a Q jet on a 425 Olds engine back in the day. Had it on a 2 bbl manifold no less. Man, the sucking noise that thing made when it hit the secondaries. The accel pump was shot so I use to have to hit throttle twice real quick to avoid the bog. Burned that motor up before I figured the carb out.

Good times.

ZONES89RS

iTrader: (25)

Yup, like I say, don't ditch it but damn sure don't be against trying a Holley out for the Eco of it. I think the spread bore should always win with fuel econemy, but the Holley should push a bit harder.

Beeterolds

I gotcha brother, im not ******* the holley.. I guess the only real issue I would have running it is the Tv cable geometry its a bitch trying to the th2004r setup just right with a holley.. working with several th2004r cars and messing with the holley I know this from experience..

If I come across a loaner I may give her a shot..

Fast86z

iTrader: (1)

I wouldn't bother with the springs. I don't think valve float is the problem here. That would be a big *** hassle only to run the same mph. I was pushing my 4.8 to 123mph and 5800 rpm with stock springs and turbo. Honestly I don't even really see much of a problem actually. MPH and ET seem pretty close to what I would expect with that.

The exhaust is potentially a bottleneck. What size are the primaries? What does the car do when you punch it? Does it hesitate at all? Have you verified your secondary air valve is opening? Does your Q-jet have a thermostat choke? If it is not hooked up, the choke could be closing some at WOT. You seem pretty familuar with them tho so I'm assuming you have the linkage adjusted for the secondaries. Not trying to insult you, just not sure what al you've checked. I've dicked around with some, most have another hole on the ACC pump linkage you could try to see if that makes a difference.

If it were mine, I would look at the converter. If it's actually flashing to 2500 and the engine isn't hesitating or bogging off the line, you should be doing much better than 2.1 60'. With 3.73s, sticky tires, and a good stall, I would expect something like a 1.8-1.9 60 which would put you in the 13s.

I would expect your combo to run high 13s. Think about it, bone stock TPI 350 cars of that period were running 14.5x at mid 90s, weighing 3500 lbs. I would say you are doing pretty good with what you've got. Get the 60' down and you will be 13s for sure.

ZONES89RS

iTrader: (25)

I pull my stockers to 6 k without falling off, if his is giving up at 5800, the springs may be an issue.

Fast86z

iTrader: (1)

If your stockers pulled to 6k why would you think his is any different? Not saying you're wrong, but playing devil's advocate.

I used to have a 383 stroker with a cam and heads. It would only run 14.55 @ 98 mph. You could feel the power choke off at 4500 RPM. Ended up being the single 2.5" exhaust. After that it ran like a raped ape. OP what are you using for an air filter?