SO I finally had a chance to time my car at the track last night and I'm very disappointed. I was aiming for 15s but hit a 16.6 @83.8 mph with a reaction time of .6988. I basically did all the mods you can possibly do for faster acceleration:

Stock port 12a

-DLIDFIS with 3 MSD blaster2s and timing set at total advance 24L 16T
-10mm Magnecor R100 race wires
-Rotary Engineering header with 2 1/2in free flowing exhaust
-summit electric fan
-2nd gen radiator
-45mm OER carb with Racing Beat one peice manifold, im running vacuum advance
-Carter 8psi fuel pump and Holley 0-4 psi regulator. Fuel set at 4.5 psi
-Fidanza 8pound aluminum Flywheel with ACT 4 puck clutch and heavy duty pressure plate
- Racing Beat 4.44 ring and pinion and a locked rear end

This was my first run at the line. I'm not to sure where the problem lies, the carb is pretty much responsive. Maybe I need forced induction.... Any advice would be great. Thanks in advance

 

Tires. I ran a 16.69 with stock carb. Basically only exhaust and ignition as far as upgrades go. Soultion? mostly bald Falken 205/60-13 tires.
Also, what rpm are you launching at?

 

Might be something in the clutch, tranny or rear end? Nice build there, looks good.

 

drop some tire pressure. how about posting a time slip so we can analyze your run.

 

you need some backpressure. i ran a header with 2 1/4 straight pipe and there wasnt alot of top end. when i swapped it out with the RB street port system there was a HUGE difference. heck even stock was a tad better.

 

I'll just retype what the time slip says:

reaction-----.6988
60ft----------2.5971
ET@594ft---10.0742
1/8ET--------10.7411
1/8MPH------67.48
1/4 ET--------16.6181
1/4 MPH 83.8

I also ran a 16 with the stock carb. I lounched at 5k, not much slipping at the line. i'm using 205/60/r13 BFgoodrich tires


I launched at 5k with very little slipping of the tires. I also ran a 16 with the stock carb...makes me wonder if i need to rejet the oer carb.

Thanks for all your replies. I just want this thing to be as fast as it looks hehe

 

give yourself a chance fella. I've run a 14 second pass at the begining of the day and finished with a 11.8 with out changing the setup on a track that was getting harder and harder.

 

thanks for the advice, yeah I was thinking that i need more practice. Felt bad that out of 3 runs I was still hitting a 16.6-16.7.

 

1/8th mi?

 

nope 1/4 mile

 

It's mainly in the rear suspension. I'm not going to try and preach at you, I hope I'm not "teaching grandma to suck eggs".

Going faster:
1. do you know where to change gear? (a dyno sheet will give you a good idea, but you should be able to feel when the torque is dropping off)

2. do you know that your rear suspension works? This is a very important question and you have to answer it properly. Just because you fitted new dampers last year and the springs are from RB, doesn't mean a thing. The spring rate should be based on the weight at each cormer, not what colour they come in. It's an old car (trust me I've got one, I know) this means the bushes are shagged and the arms are bent, the axle is twisted and the guy that crashed it 6 years ago probably filled the floor pan with fiberglass. Alright that might just me my car, but you get the idea. You don't know it's good until you actually find out. Does the rear suspension move properly, through the entire travel?

3. is the front suspension stopping the rear get traction? The front needs to lift to allow the rear to squat... standard shocks and springs are probably your best bet.

4. 10.98 @ 138mph to beat... stock rear end on koni dampers, 12AT/T51R Rx8 gearbox, Microtech and slicks.

you'll get there.

 

My first thought is the 60ft sucks. I know our cars are slow but I would think you can get at least a 2.0 60ft. I run about 15 lbs of tire preasure when I drag race. Maybe that will help. I also think launching at 5k is too high. try 4k and learn how to slip the clutch instead of totally dumping it. This should help a lot. Good luck my friend.

 

Hey man, don't be disappointed. One thing you have to keep in mind is that some of the 12a's from the factory, especially the heavy 85 GSL, only ran a 17.4 second quarter mile. You are already in the 16's and probably can knock at least another second off your time just by becoming a better driver. I would say that with all your mods and with the proper tires, a 14 second 1/4 mile is not unrealistic. And listen to the guys that speak about suspension mods--they are right. In the past, I never knew that this was even an issue, but my step-dad has been racing all his life and said that suspension makes a very noticeable difference.

Mike

 

Thanks for the tip, I'm just getting into drag racing. I have a flat spot on the carb that's why i cant launch any lower, hopefully my next run turns out better.

Yeah you guys are right about the suspension, i noticed some wheel hop as i was burning out. I'm still looking into buying replacements but you guys know how it is when you're trying to work on 2 cars at a time right? Hehe but don't worry i'm taking ALL the advice you guys give. 15s is my goal but 14s would be fantastic.

-Ronald

 

You could improve the 60' by picking up a set of street slicks... (Nittos or BFGoodrich for ex) drop the tire pressure, heat em up with a real good burnout and you'll be droppin the clutch out the hole higher then 5K for sure with no or minimal tire spin once you find the right rpm area. There's always a price to pay though... you'll quickly find out what part of your driveline is the weakest.

 

Another tip, if you're running just street tires, don't burnout. Street tires get slippery and loose traction when they are heated up to drag temps. A good set of drag radials will do nice.

 

Practice, practice practice. Work on your reaction time. I'm not going to pretend I know anything, because I've honestly never been to the strip, but I think it's anything under .500 is really good, so shoot for that. Spend alot of time watching the tree. Plus try tuning your carb at the strip, after each run. Change your jets up a size or down and just run it, see what happens. Keep in mind how sensitive carbs are to fluxuations in air temperature. Your sitting in a warm climate on a track thats had cars running down it all afternoon, so the air coming off the track is going to be warmer than just driving down the street. Good luck.

 

Sounds like good advice so far. All I'll add is:

tuning tuning tuning...

You've got a lot of really nice parts, but how well is everything actually working?
You'd be amazed at how much horsepower is hidden in ignition alone, or maybe you already know since I see you've covered that already. How about the carb? Is it performing as well as it possibly could be? Just some ideas. Nice looking car man.

 

You could check out the 1/4 mile thread for some ideas. These cars aren't exactly built for drag racing, especially not with an n/a 12a or 13b.

 

My thoughts exactly. Unless that carb has been tuned with a wideband or on the dyno, then there's most likely some hidden hp to be found. Then work on you RT and 60' times. Tires will make a major difference on launch and 60' times, that's where many races are won or lost.

 

yep you guys are right, pratice is what i need. OK i did some research on the carb( what is the correct jetting for stock port 12as) and i compared it to mine and found that my pump jet was a lil small, its a 40. I have f-16 emul and 170 mains. I think i need to rejet this thing. Probably the flat spot during my launch is due to that small pump jet.....I would like to ''experiment'' with the timing but I think I its good where its at. Here on Guam drag slicks for 13in wheels cost an arm and a leg, $300+ a peice. From your replies I figured I need ALOT to focus on, so right now i'm focusing on the carb. DOes anyone have a perfect combo of jets and emu-tubes etc? That would be great.

 

There is no "perfect combo" for jetting. It depends on a variety of criteria. Elevation, air temperature, humidity, etc. That's why carbs need to be tuned pretty much every time the weather changes. Get used to it, your going to run into a day every now and then that you'll have to spend a bit of time trying other jets.

 

you're right I guess it's all trial and error from here

 

Not if you buy a decent wideband that has the ability to log. I have an Innovate LM-1 that has a hand held unit that a co-driver can watch the readout in real time. It will also log and save runs so they can be downloaded to the computer for analyisis.

There are 3-4 major brands of widebands to choose from. Find one that suits your needs the best. In the long run, it will save time, money, wear and tear on the engine.

 

For dragracing,you need to ditch the light flywheel,killls the rotating inertia that helps you not only get out of the hole.but keeps the momentum all the way down the track,second you timing is advanced way to far for a non ported motor,those sidedrafts are known for having a flat spot at around 3,000 rpm,as far as 60' i was running 2.0 on street tires,i made adjusters for the upper links of the rearend to make the instant center farther back,it eliminated any wheel hop,and made the car hook very well,i never got a chance to run it with slicks,but properly done,it should run 1.45-1.50 60' times