Going racing + dyno tomorrow. Predictions?

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magnumdust

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So even though gas prices here in cali have spiked courtesy of a fire and shady oil company dirtbags, i'm going racing. Mainly because a local shop is bringing out their mobile dynojet.

Specs:
Junkyard 360 magnum(turned out to be a freshly rebuilt engine)
Hughes Iron ram heads(stock 1.9x valve)
Custom ground cam from IMM
crosswind air-gap intake
3000 stall convertor
Hedman headers
3.55 gears
edelbrock 600cfm carb
Timing set at 16 initial 32 total
Tuned via wideband to 12.5:1 a/f at WOT

Specs on the cam(though i know zero about them):
Gross valve lift: intake/exhaust: .513
duration @ .006: 276/282
duration@ .050 : 224/230
Lobe lift: .3210/.3210
Lobe duration: 110

Ran a 14.7 last time out with the late 70s tranny shifting at 3-500 in first and 2nd gear.(now using shift-r-gate to shift at 6k between gears)

Hoping to crack 300whp, though i'm gonna bet my heavy 17s will rob some power.
 
Not knowing what size tires
Or what your previous 60' time was
I'll guess mid 13's
Sounds like fun,starting to cool off here
On the east coast.
 
I'd be thrilled with any of those times. Especially 12.90s, that would mean except for a good tranny and some drag wheels/tires, I'm done.

As for winning, that's pretty unlikely. Unfortunately it was rediculously consistent with the old crap engine, but this one spins too much off the line.
 
Here's a old school trick.Ignore the water box,drive around it.Before you enter the stage area,whack the gas pedal hard,for a sec.Preloads the converter,then stage.Try it,it works.
 
Abodybomber said:
Here's a old school trick.Ignore the water box,drive around it.Before you enter the stage area,whack the gas pedal hard,for a sec.Preloads the converter,then stage.Try it,it works.
Click to expand...

hmm, i'll have to try that converter thing. I've always avoided the water box. Generally i just give the tires a quick spin to kick off any gravel since the pit area has a lot of loose asphault that will stick to tires after a run.
 
Well things didnt go quite as I hoped. The car has some tuning issues and was for lack of a better word "coughing" after 4500rpm. I suspect maybe the 600cfm carb is running out of breathing room and it didnt crack the 14s tonight.

Mobile dyno shows 246rwhp/265tq. Not bad considering their wideband showed the car as still too lean at wot and they didnt have any real cooling provisions. Just a leaf blower(no joke)

Anyhow, all that said i've decided to put the car up for sale. Carb's are driving me nuts, i'm gonna step up to something modern and fuel injected.
 
Coughing above 4500 was cause it was too lean. Not the carb size. If it was too lean it only takes 30-40 minutes to change jets.
 
Get it jetted properly. Eddy carbs are a breeze.

Probably run much better with a 750 holley on it.
 
crackedback said:
Get it jetted properly. Eddy carbs are a breeze.

Probably run much better with a 750 holley on it.
Click to expand...

I have a holley 750. It was actually sitting in my back seat at the track, but i dont have the fuel inlet rail and i don't wanna spend 30-40 bucks for a cheaply made spectre unit in town.(i was hoping i could find some hardware store inlets to work, but nothing with the right thread count is there.)

And really, if my car doesn't sell this time around on CL, im gonna skip the carb BS and build a megasquirt TBI efi for it. But i've already gotten one trade offer...a 1985 6 door caddy limo...sigh, i hate CL so much.

And now that i've had some time to play with my windows movie maker, the video of my car on the dyno. Note: turn volume down, very very loud.

[ame="http://www.youtube.com/watch?v=5Snn-kbpAx8&feature=youtu.be"]1973 duster mobile dyno - YouTube[/ame]
 
How lean was it? If it was in the 13's or higher there's possibly 30-40+ hp. If it peaked at 4500, there's WAY more in it.

Carbs are easy to tune up, especially for full throttle. With the time it will take to build a megasquirt, you can have the carb figured out.
 
crackedback said:
How lean was it? If it was in the 13's or higher there's possibly 30-40+ hp. If it peaked at 4500, there's WAY more in it.

Carbs are easy to tune up, especially for full throttle. With the time it will take to build a megasquirt, you can have the carb figured out.
Click to expand...

The sheet they gave me looks like it was right about 13:1 at wot. And peak looks to have come in at 5200rpm. I'm not sure why it got up that high on the dyno, but acted differently down the strip.

Honestly, i'm done with carbs. Its been the biggest headache with this car. I spend more time fiddling with the tune to try and get a reasonable streetable setup(something better than 10mpg) than i do racing it. I mean i like tinkering with stuff, but at some point you have to be able to drive the car more than 500 miles a year.
 

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That should run 13.00 or better if it hooks at 103-106+ mph.

Too bad you aren't closer. It's a relatively easy fix.
 
the guys on here will help you tune the carb. if you have the 750 holly already it would be ALOT cheaper to buy a fuel rail for that than it would be to build a fuel injection. would only take a few min. to swap it out. who knows it may make a huge difference. Don't let the carb get you frustrated. you have an awesome looking car. just gotta do some tweaking.
 
Yes, sell the car because I can't get the carb dialed in.....said no car guy EVER!! :D

Seriously though, converting to fuel injection is going to be a much bigger pain and WAY WAY more expensive than just tuning the carb (or buying a new carb for that matter). If you want a really easy fix, or if you have no carb tuning knowledge, sell your carb and buy a custom tuned carb from Jesse Bigs, Pro systems, etc. Bolt on and go usable performance with little to no tuning needed for the average Joe.

Last note, for what its worth, the dyno numbers probably aren't too far off for what you described at the top of the page. Properly tuned you still might not make 300 WHP, but if you are having fun driving it, that's all that counts.
 
flyfish said:
Yes, sell the car because I can't get the carb dialed in.....said no car guy EVER!! :D

Seriously though, converting to fuel injection is going to be a much bigger pain and WAY WAY more expensive than just tuning the carb (or buying a new carb for that matter). If you want a really easy fix, or if you have no carb tuning knowledge, sell your carb and buy a custom tuned carb from Jesse Bigs, Pro systems, etc. Bolt on and go usable performance with little to no tuning needed for the average Joe.

Last note, for what its worth, the dyno numbers probably aren't too far off for what you described at the top of the page. Properly tuned you still might not make 300 WHP, but if you are having fun driving it, that's all that counts.
Click to expand...

No, its "sell the car because i'm tired of having something isnt all that impressive at the track, costs 70 bucks(in gas alone) to go racing, and is such a pita that i've generally had more fun driving my slow 15 second truck at the track.

I mean really, pick anything from the late 90s-to early 2000s. They'll do what my car *may* be capable of with some simply bolt-ons, ride nice on the highway, and not get dismal mpg. Hell even if i keep and modify the car, by the time i get overdrive/efi/handling suspension under it, i will have spent as much as it would cost to buy one of those newer cars.

Not to mention, there is just no replacement for banging gears and an overdrive 5spd is a nightmare in these cars.

Anyhow, just for the hell of it, i ordered an inlet line for the holley 750 i've got. I figure that with the gas spike here in Cali, i'll be waiting a few weeks before i get a buyer. At the very least, the holley w/ hard line will clean up the engine bay a little. That crappy spectre deadhead regulator has always bugged me.
 
magnumdust said:
..........

I mean really, pick anything from the late 90s-to early 2000s. They'll do what my car *may* be capable of with some simply bolt-ons, ride nice on the highway, and not get dismal mpg. Hell even if i keep and modify the car, by the time i get overdrive/efi/handling suspension under it, i will have spent as much as it would cost to buy one of those newer cars.................
Click to expand...

Your Duster will definitely be WAY cooler than anything from the late 90's-2000's....I'm just sayin.....no belly button cars for me thanks.
 
It's a tuning, knowledge issue. I'll bet there are few issues that are stacking causing your lack of performance. It's a great time to learn something new!

Have you moved the total timing at all. It's not a quench engine if the pistons are in the hole any. It may want another 4* of total.

Since you have a wideband, what type of AF levels do you have when driving on the road?

That engine should make real close to 400 fwhp. Peak should be in the 5600-5800 range. It's 600 rpm short of that. It's making more in the 330-350 at best.

Personally, I'm not an ede carb fan. Can they work yes. Are they better than a holley, not IMO. Have you changed a jet or metering rod in the current carb?

Read the ede tuning manual that is on their site and get to work. Changing the carb may not do anything for you if you aren't willing to learn how to make it work. This stuff doesn't just fly out of the box and work perfect every time. Sometimes you get lucky, most of the time it takes refining.

This car with a 360 and a xe268 cam, 2500 stall and 2.76 gears ran over 104 at vegas with a OOTB holley 750DP and a DA in the 4800 range. It was a smidge rich there.

[ame=http://smg.photobucket.com/albums/v655/crackedback/?action=view&current=DemonontheRoad009-1.mp4]
th_DemonontheRoad009-1.jpg
[/ame]
 
I am sort of in the same boat as you man....I have a 360 with a eddie 600 carb. My friends have been bugging me non stop to take it to the track but with 2.73's i dont really want to so i am waiting to get my new rear end in with 3.55's in it. I have been very curious as to what it runs and the hp numbers and we have a very similiar set up. I have read a million things sayying to get rid of the 600 eddie and get a 750 holley dp. I am going to do that and swap out the intake and pray for a twelve to thirteen e.t...dont give up and dont be afraid of swapping jets. I have playyed around with efi alot and it can be a major pain also.
 
crackedback said:
It's a tuning, knowledge issue. I'll bet there are few issues that are stacking causing your lack of performance. It's a great time to learn something new!

Have you moved the total timing at all. It's not a quench engine if the pistons are in the hole any. It may want another 4* of total.

Since you have a wideband, what type of AF levels do you have when driving on the road?

That engine should make real close to 400 fwhp. Peak should be in the 5600-5800 range. It's 600 rpm short of that. It's making more in the 330-350 at best.

Personally, I'm not an ede carb fan. Can they work yes. Are they better than a holley, not IMO. Have you changed a jet or metering rod in the current carb?

Read the ede tuning manual that is on their site and get to work. Changing the carb may not do anything for you if you aren't willing to learn how to make it work. This stuff doesn't just fly out of the box and work perfect every time. Sometimes you get lucky, most of the time it takes refining.

This car with a 360 and a xe268 cam, 2500 stall and 2.76 gears ran over 104 at vegas with a OOTB holley 750DP and a DA in the 4800 range. It was a smidge rich there.

Click to expand...

Hopefully i can provide some reasonable answers to those Questions:

Total timing hasnt been moved. I kept it at a total of 32. Honestly i had no idea that it was breaking up at high rpms because i havent been able to go somewhere to let it out. I've got one too many tickets, so i can't afford another from screwing around with my car.

Wideband showed 12.5ish wot and, hovers around that around town and on the highway is anywhere from 12.9-13.5. However, i still wonder about the accuracy given that the guys at the dyno claimed it was too lean. I may go recalibrate it here in an hour or so just to double check myself.

I have changed rods, it has #1427 jet & 1455 rods. #23 on this chart:
1406cal.jpg


Though looking at that chart, i do wonder if #3 or #25 would be more advisable in richening the WOT and giving the car better cruise manners.
 
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