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It says that those parts on a 383 will make 460 dyno proven horsepower. I have a balanced Eagle bottom end with pistons that should bump the compression to about 10.5:1
I have a street avenger 670 fueling it right now.
Now here's the thing, I took it to the track expecting 12s easily out of it, and it ends up running a 14.6@94mph.
The only thing I can think of that might be my problem is the tranny isn't transfering all the power or something, it's a 700r4, or the carb sucks (which it does).
What should I try? I hope to have the thing dynoed here soon.
Re: With these parts I should be pushing 500hp, the track numbers say otherwise.
So you bought the E-Tec 200 heads? They're decent but they dont flow as well as advertised out of the box. I'm guessing you have a port mismatch between the heads and the intake manifold. You also didnt mention if you're running headers or stock manifolds and exhaust.
Re: With these parts I should be pushing 500hp, the track numbers say otherwise.
The carb sucks for one... you're way down on power going by the trap speed. When I first put my 350 in I had expectations like you. It was only running 101-103 mph doing mid 13's now it's doing 114 mph and high 11's after a bunch of little changes to make things work together better.
__________________ Best times to date, motor pass: 11.81 @ 114.55 1.63 60' 10/18/08
nitrous pass: 10.49 @ 126 mph 1.42 60' 10/18/08
350, AFR 195 heads, Eagle H-beam 6" rods, Victor Jr,
750 Race Demon, ProMagnum RR's, Hooker LT, TH400, Spohn T/A and C/M
Re: With these parts I should be pushing 500hp, the track numbers say otherwise.
460 at the crank I would think should run low low 12's without problems, if everything else is up to snuff. What's the rest of your exhaust system like? What was your 60'? What size stall are you running? Can you borrow a 750 double pumper from a buddy to try? What ignition are you running?
Re: With these parts I should be pushing 500hp, the track numbers say otherwise.
The 700R4 is a poor transmission for racing anyway. The spread between 1-2 is too far apart and the rpms drop down too much after the shift.
The Edelbrock package doesn't say it but you should have a converter that stalls 3000 - 3500 rpm for that camshaft. If you're using a stock stall speed, the engine isn't coming into the powerband fast enough and performance is suffering because of it.
__________________
Hardtail Racing
All engine, no power adders! Bests: 9.029@150.45 (at altitude)
Theoretical sea level performance 8.623@157.05
Re: With these parts I should be pushing 500hp, the track numbers say otherwise.
My best 60' has been 2.025.
I am running a stock converter on it and the rest of the exhaust is a 3'' collectors into a 2.5'' y-pipe going to the back and then split into two after the muffler.
Re: With these parts I should be pushing 500hp, the track numbers say otherwise.
[.594/.594 lift- 242ᄚ/240ᄚ duration @ .050) used in EDL SS383
Thats a fairly large cam, higher stall is definitely a must. It will make a huge difference. Also, setting up the carb for that cam will be a bit of work and fine tuning will go a long way. Get rid of that avenger and put a dp 750 on it.
The trans should still give you some decent times, hope its not stock though, it wont last long.
Re: With these parts I should be pushing 500hp, the track numbers say otherwise.
that cam, those heads, and that intake should make good power. the carburetor sucks go with a 750DP and 3000 stall minimum.
i had the RPM package. .488/.510 cam, 1.6 pro magnum rockers, edelbrock rpm heads 170cc, rpm air gap intake, 750cfm edelbrock, march pulleys, long tube headers, with 2.5" true dual exhaust with 700r4 built, and 4.10 posi in 7.5" rearend. i cut 2.0 60 ft and ran a best of 12.6 @ 111mph
Re: With these parts I should be pushing 500hp, the track numbers say otherwise.
New carb 750DP or a HP seires, At least a 3500-4000 converter, Long tube headers make a world of diff. on these cars and a good exhaust no flowmasters stick with a straight thru type such as magnaflows. Whats your total timing and are you shure your ballincer is indiexed right?Also do you have enough fuel pressure ?
Re: With these parts I should be pushing 500hp, the track numbers say otherwise.
not having the higher stall is what is really killing you. the 670 CFM carb seems a bit small to me.
if you go to the top right of the holley page ( http://holley.com/ ) there is an interactive carb selecter, that should at least put you in the right direction.
what suspension mods do you have? remember any time spinning is lost time. suspension would definitely not be a bad investment.
Re: With these parts I should be pushing 500hp, the track numbers say otherwise.
a 750 double pumper minimum for drag race duty!!!!!!!
get good lower control arms (dont have to pay much=ebay) and do lower control arm relocation brakets!!!!! put an air lift airbag inside your right rear spring these 3 items took .2 off of my 60 foot
i have a 452 horse @6100
427tq at 4800
355 9.77 to 1 comp
700r4 manual valve body 3000 stall (i only get about 2700)
and i run 12.29 @112mph with a 1.77 60 foot
It says that those parts on a 383 will make 460 dyno proven horsepower. I have a balanced Eagle bottom end with pistons that should bump the compression to about 10.5:1
I have a street avenger 670 fueling it right now.
Now here's the thing, I took it to the track expecting 12s easily out of it, and it ends up running a 14.6@94mph.
The only thing I can think of that might be my problem is the tranny isn't transfering all the power or something, it's a 700r4, or the carb sucks (which it does).
What should I try? I hope to have the thing dynoed here soon.
That combination of parts should run easy 12's as is with the 670 carb. Your trap speed is way down from where I would expect, you are not making anywhere near the 460 HP you were hoping for. Assuming your transmission is not slipping I would check your timing at WOT, it should be between 34 and 36 degrees. If your timing is good and you are not missing I would check to make sure your cam is installed correctly. The stock torque convertor will hurt your ET but it will not have a large influence on your MPH in the quarter. I would expect to see 110 plus MPH in the quarter with that combination.
__________________ 1988 Formula 5.7L/6sp 3.91 gears,10.6 cr, SLP cold air kit, MAS gutted, TPIS air foil, TPIS AFPR, Superram, MAC headers, Mac under drive pulleys, MAC cat back, Relocated MAT, E-Tec 200 heads, SDPC Vortec manifold, ZZ-409 cam.
Best ET 12.17
Best 60 FT 1.754
Best MPH 113.1
RWHP 369
RWTQ 399
Re: With these parts I should be pushing 500hp, the track numbers say otherwise.
Quote:
Originally Posted by bjankuski
That combination of parts should run easy 12's as is with the 670 carb. Your trap speed is way down from where I would expect, you are not making anywhere near the 460 HP you were hoping for. Assuming your transmission is not slipping I would check your timing at WOT, it should be between 34 and 36 degrees. If your timing is good and you are not missing I would check to make sure your cam is installed correctly. The stock torque convertor will hurt your ET but it will not have a large influence on your MPH in the quarter. I would expect to see 110 plus MPH in the quarter with that combination.
That's exactly what I was thinking, that I should be able to run easy 12s in the quarter. I was sorely disappointed when it ran the 14.6.
Re: With these parts I should be pushing 500hp, the track numbers say otherwise.
It dogs pretty bad off the line, I'm pretty sure that just the carb, which I've been thinking about getting a new one since I started this engine. It shifts pretty hard going into 2nd then you can't hardly tell its shifting into the other gears.
Re: With these parts I should be pushing 500hp, the track numbers say otherwise.
A 750 DP carb and a 3200 to 3500 stall converter wil get you in the high to mid 12's. You should do some suspension work and get some wide slicks and you will run low 12's.
Re: With these parts I should be pushing 500hp, the track numbers say otherwise.
Just a stall will make up almost 2 seconds?
The tranny is completely stock, out of a 1993 Buick Roadmaster wagon
I only actually made 1 quarter mile pass, I had to talk the track owner into letting me run once after all the actual racing was done. The rest were all 1/8 mile time trial passes. I actually just found the slips from May. Bolded is my first run ever.
Re: With these parts I should be pushing 500hp, the track numbers say otherwise.
its not stall... even stock stall should have that car trapping much higher than 94
yes the converter is holding him back alot but come on, does having 3000 stall give him 15 more mph that he's missing and 2 seconds??? No i dont think so, that seems too much to gain. 383 should have ample power from idle to 5500 rpms with that cam/head setup
its in the tune. that combo should be good enough for the power, it just needs tuned up. New carb probly
Re: With these parts I should be pushing 500hp, the track numbers say otherwise.
no your right i dont see a new stall gaining that much... it will help with the 60' potential....i mean with 4.56 gears i would think the 60' would be much lower if he had traction
do you know if your secondarys are opening properly?
have you made any adjustments to that carb?
or to timing?
Re: With these parts I should be pushing 500hp, the track numbers say otherwise.
You know, I've never been too sure about this carb, even since I've had it uptop a 355. I wanted to get something with mechanical secondaries, for a while now.
As for the timing, I can't recall a specific number right now, but I know it was set to whatever the Edelbrock package said.
I've been thinking now for a while to just go ahead and get a stall and a racier transmission. Even before this engine was started.
Re: With these parts I should be pushing 500hp, the track numbers say otherwise.
Quote:
Originally Posted by Orr89RocZ
its not stall... even stock stall should have that car trapping much higher than 94
yes the converter is holding him back alot but come on, does having 3000 stall give him 15 more mph that he's missing and 2 seconds??? No i dont think so, that seems too much to gain. 383 should have ample power from idle to 5500 rpms with that cam/head setup
its in the tune. that combo should be good enough for the power, it just needs tuned up.
I agree, completely. The worst converter and gears in the world, on a proper running 383 would result in terrible 60' times, but you'd still trap over 110 with 400+ hp. Even w/good gear, you're getting neither a good 60 nor good )or even close to decent) trap. Trap tells you everything about hp and your trap is telling me that you're making about 250 hp. I used to trap 95 w/a 305 Crossfire that had headers...and that's it. So something is WAY out of whack.
What tuning measures have you taken, thus far? Plug reads? Timing checks? These are very important, basic checks and can make a HUGE difference. Though I hate the Edelbrock carb, that isn't your problem either. You need to tell us what your timing is, and what your plugs are telling you.
Lastly is your driving. This isn't your primary problem either, b/c a terrible driver w/400+ hp will still trap over 110. But you posted reation time. FORGET about reaction time! It doesn't matter. your time starts when your front wheels clear the second light. Forget reaction time, and launch your car, when YOU are ready, and the car is ready. "Use" your concentration on launching, not R/T'ing.
Quote:
Originally Posted by cubemaniac
You know, I've never been too sure about this carb, even since I've had it uptop a 355. I wanted to get something with mechanical secondaries, for a while now.
You can turn that carb into a Mechanical secondary carb by removing that goofy counterweighted "drawbridge" flapper door on the secondary side. You'll need to max out your accelerator pump shot to accomodate the lack of the "flapper door", but I did this to an Edelbrock 750 CFM carb I had on a 350, and I swear, I picked up 20 hp from just that mod alone. That mechanism sucks.
Last edited by Tom 400 CFI; 07-10-2008 at 01:46 AM.
Re: With these parts I should be pushing 500hp, the track numbers say otherwise.
The 4.56 gear is excessive unless you're running a very tall tire. With that cam you're going to want to run at least a 3,000 stall and I'd look into a 4.10 gear. Judging by what you're running I'd say you have an issue with timing and fuel. If you're running E-Tec heads remember that they don't need as much ignition advance as normal old style sbc heads. Put a wideband on that thing and get the fuel/spark timing dialed in. Even with a stock converter and a 2.73 gear you should be faster than that.
__________________ 2006 Silverado 1500 RCSB 2wd 5.3L 345RWHP/341RWTQ. Comp Cam 222º/224º .566/.568 112LSA, 2600 stall, 3.73 gear (stock), Detroit Locker, 160º thermostat, Corsa Sport cat back, Outlaw cold air intake, Pacesetter long tubes.
13.59@100.34 2.04 60' In full street trim with no weight reduction and on the 20's.
Re: With these parts I should be pushing 500hp, the track numbers say otherwise.
Exactly. Guys have ran in the 10's and 11's without subframe connectors and on stock control arms. They are better to have, but not required for a good time. If you like to be able to open and close the doors properly you do subframe connectors, not for the time gained. He's running slower than a stock LT1 F-Body and those are only 275-285hp. At this point he's not really making enough power to even twist the body.
Re: With these parts I should be pushing 500hp, the track numbers say otherwise.
Your going to need a bigger converter for sure!!. That cam is alittle big to me, what does the cam card say for rpm?? Make sure its timed right and I would at least get some 4.10s, but all this is just my 2 cents.
Re: With these parts I should be pushing 500hp, the track numbers say otherwise.
Quote:
Originally Posted by HawkHunter
You'll loose throttle response and vacuum if you goto a 750+ carb, which will result in your distributor not advancing at the top end (im assuming it has vacuum advance) and all of your vacuum assesories quiting - if you dont care about streetablility (race only car) get a 3500 stall though and you'll see a noticable difference.
Umm probably you should do some more learning on the topic before posting ignorant statements. That carb has nothing to do with vacuum advance. Either carb will provide vacuum advance. When you step on the throttle the vacuum goes away and so does the "vacuum" advance to prevent spark knock. But while high vacuum cruising it is advanced for fuel economy. Distributors are advanced mechanically by weights and springs. sometimes distributors are mechanically locked at a fixed value say 34 degrees for a drag race type of car.
Vacuum acessories will work equally as well with either carb. Its the engine setup from the ground up that causes low idle vacuum. Or sometimes an individual will get overly aggressive in camshaft selection with alot of overlap and cause issues with vacuum. This kit may actually have low idle vacuum but thats not his problem. Its missing some serious hp from a lack of a correct ignition curve, or a fuel problem, camshaft issues, some research needs to be done.
Re: With these parts I should be pushing 500hp, the track numbers say otherwise.
Since from now to then I have replaced the stock distributor with a pro comp racing distributer that is good up to at least 9000 rpm and an 800 cfm dp.
Both have made a noticable difference. Stall is next though./.
I was going to take it to the drag strip last night but they closed the track due to rain. Maybe this Saturday or next wednesday.