disapoining et

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do you have any cylinder pressure? if so, what is it ?
 
pay no attention to the smallblock boys, a properly built 383 will walk all over a smallblock. I think your combo is just a couple parts and tweaks away.
 
highwaystar said:
I got to say it.. Its the big block that is slowing your A-body down. Everyone likes the idea of a big block in an A-body, and that It is going to be soo fast.. Reality check here.. I know this is not helping your need, and this could be covered under a whole different thread, but like I said had to say it.. A Stock 340/ good 360 with stock cam and manifolds run better than that all day long at the track.
More than likely get your timing right and Carb right, and proper traction you will pick up 3-5/10ths. Like the guys are saying. your not going to see low 12's, without a lot of changes in gear, traction, and more H.P
Click to expand...

Really, the big block is slowing it down?

A stock 340/360 will run better all day long?

I'm calling you out on this one. Please explain in detail your warped logic.

I've owned 3 Darts, a /6, a small block and 2 big 440 big blocks. I can't wait to see this..... :coffee:

fishmens67 said:
pay no attention to the smallblock boys, a properly built 383 will walk all over a smallblock. I think your combo is just a couple parts and tweaks away.
Click to expand...

This is almost as bad as the post you are referencing.
 
arguing about whether a SB would kick a BB rear helps a lot. Maybe it's the air int he tires.

Good luck with this.
 
sounds like we have established a couple things here.

1. the carb is wrong.

2. you need some solid info about your tune.

Here is what I would do. I would swap on either a new or known good running 750 dp. with mech. secondaries.

I would then address timing. I would start with the cam. i would pull the timing cover and degree the cam. I would make sure it wasn't installed retarded. i would set it up per the cam card.

I would then bolt it all back up and set your initial at between 15-18* and all in by 2500rpm with a total timing of about 35-38* this will require some screwing with the dizzy. those numbers should get you in the ball park.

then go to the carb.

1. set fuel pressure to 6lbs
2. adjust floats till fuel just barely dribble out the sight holes
3. set idle mixture to give you highest vacuum reading at idle
4. as idle increased back off the curb idle screw and redo step 3.
5. check vacume at vacume port on idle. cut # in half and that is size power valve you need in the front.


you should now be in the ball park. this set up should run good and only need light tweaking from then on.

or i could be full of **** but this is exactly what i did with my 383 and it took it from a disappointing heap to a tire melting monster.
 
lrazor said:
As others have stated and most are ignoring, that mph is too slow. Are you sure that you are getting full throttle opening?
Click to expand...

3 pages of idea's and he hasn't done a one of them. and there was some posted about the mph but its kinda obvious... and that was stated already
 
Of his engine guy that's tellin' him he needs gear, slicks, VB, etc.!!!

Lotsa good info you're being bombarded with...
And as more than a couple have mentioned, Carb and Tune!

Your run mentioned is bad all around for what you have, bad 60', bad ET, bad MPH.

I would think your car, with nothing but a good carb and tuning, has at least a half second better in it (or more), no problem. 100 mph should be no trouble as the cars sits.

Tell the engine guy put up or shut up, this thing's a dog!
 
I got really tied up with work. I been checking back here and seeing what you all are posting. I really appreciate the info but can't do anything about it until tomorrow. Thanks again and keep the ideas coming!
 
I'd like to see a list of what you plan to do first. Take all the stuff suggested and start from 1 to whatever in order of sequence to check/change.
 
the sequence of how im going to trouble shoot based off everones sugestions:
1. Check compression
2. Check Timing
3. Check carb tuning (i have to use the one i have for now) will also check if i am getting WOT as mentioned earlier.
4. take it to a dyno. when i have funds for it
BTW. the cam was degreed when it was installed.
once i do that i will re-evaluate changing parts. I know that the overall setup is not optimal and will be adjusting things as the budget allows.
 
Before you spend money going to a dyno, get a different carb. Carb should be #1 on your list!

If you must use that POS carb, find out what the rear metering plate is installed in it. Jet the primary closer to the metering plate size. If someone sold it to you, I'd stuff it back in their rear.

Read Younggun's post and time it like he mentions, should be close. Total timing method is a rotten way to set timing on a street driven car! If you don't know how to adjust stuff do a search, there are literally hundreds of "how do I time my engine" posts.
 
I don't even see how that 660 even works on this, it has 1 50cc center discharge pump. The main and secondary side get fuel at the same time from a center mounted squirter. It would go faster and run better with a 2bbl on it.
Not to stur things up but a Holley 660 Aka 6224s which have "No power valve" the power valve holes are blocked come with #76 jets in the primaries and secondary plates equivalent to #76 jets in the secondaries.
 
crackedback said:
Before you spend money going to a dyno, get a different carb. Carb should be #1 on your list!

If you must use that POS carb, find out what the rear metering plate is installed in it. Jet the primary closer to the metering plate size. If someone sold it to you, I'd stuff it back in their rear.

Read Younggun's post and time it like he mentions, should be close. Total timing method is a rotten way to set timing on a street driven car! If you don't know how to adjust stuff do a search, there are literally hundreds of "how do I time my engine" posts.
Click to expand...


my post was blatant plagiarism of the advise given to me by cracked back. lol
 
crackedback said:
Before you spend money going to a dyno, get a different carb. Carb should be #1 on your list!
Click to expand...


808 Duster....Listen to Rob (crackedback) here. He knows what he's talking about. Every comment he's made is relevant and helpful. Try a diff carb like a 750dp, do a compression check too, and go from there. Report back and let us know what you find. Rob is right with that mph your not making the power your combo looks like it should on paper. Don't go crazy with valve bodies, 4.56 gears, and rear suspension mods and lightening it up for craps sake, gimme a break. Do a comp check, swap a 750 on it. Read your plugs. What are they telling you? Those are 3 quick/easy things to do that will tell you a lot.

Good luck! You'll get there....heck, my junk stock '78 smog 360 with a bazillion miles on it & 3.23's ran 15.0 @ 90mph in my 70 Duster on a 275/50 drag radial and just a 625cfm carb on the stock iron intake and headers with 2 1/2" duals, your leaving a lot on the table. You'll get it, don't worry.
 
Also I've got my Quick Fuel 750vs Slayer for sale here in the classifieds section. Rob may not agree it's the best choice, but I think he'd agree its way better than what you've got and will work very well on your combo! Shameless plug for myself, but also trying to help ya out. Would be way cheaper than a Holley 750dp and bang for the buck, my Quick Fuel would probably help ya out considerably. Ok, end of shameless self promotion...LOL.

Let us know what you comp check comes back like. My smog 360 was in the 95-110psi range, a total pig relatively speaking and I was still abl to tune it to run strong off the line. It was completely done by 5000rpm but that's to be expected. My point being if you find your comp is on the low side, don't worry too much as long as all cyl's are within 10-15psi and it's not showing any other obvious signs of serious issues. You can still get some good grunt out of it no doubt!
 
When you pulled a plug, where did you pull it from? Did you pull a plug from the 7 or 8 hole to see what they looked like? I bet they look different than the 1 or 2 holes. This is where you'll see an issue with jetting imbalance. Another member had the same thing with jetting and the car wouldn't run like he thought it should, 13 step difference, got it narrowed up and the car picked up. You have roughly a 10 step difference with no power valve, which is huge... You're feeding the front half of the engine a lot more fuel/richer than the rear half.

Advance springs - take off the garage door spring if it's that huge one that originally comes on the MSD. Put 1 light silver and 1 blue spring on it. Those heavy springs wreak havoc on timing curves in those distributors from what I've seen. At idle you should have about 18-20* of timing. The engine should idle pretty easily at 800-850 rpm in p/n and only drop about 50-75rpm in gear.

Good luck with it.

P.S. Beatniks carb is a much better choice than the one currently in use.
 
younggun2.0 said:
sounds like we have established a couple things here.

1. the carb is wrong.

2. you need some solid info about your tune.

Here is what I would do. I would swap on either a new or known good running 750 dp. with mech. secondaries.

I would then address timing. I would start with the cam. i would pull the timing cover and degree the cam. I would make sure it wasn't installed retarded. i would set it up per the cam card.

I would then bolt it all back up and set your initial at between 15-18* and all in by 2500rpm with a total timing of about 35-38* this will require some screwing with the dizzy. those numbers should get you in the ball park.

then go to the carb.

1. set fuel pressure to 6lbs
2. adjust floats till fuel just barely dribble out the sight holes
3. set idle mixture to give you highest vacuum reading at idle
4. as idle increased back off the curb idle screw and redo step 3.
5. check vacume at vacume port on idle. cut # in half and that is size power valve you need in the front.


you should now be in the ball park. this set up should run good and only need light tweaking from then on.

or i could be full of **** but this is exactly what i did with my 383 and it took it from a disappointing heap to a tire melting monster.
Click to expand...

I agree. A good carb choice and tuning,tuning tuning!!! I took my heavy 72 340 cuda from mid 14`s to low 13`s by upping my 650 to a 750DP and tuning it- jets, pumps, squirters and timing curve. Tuning and reading plugs is a lost art. You need to spend a day at the track and make ONE change at a time and see if it helps or hurts you ET and MPH. I also put on a set of drag radials in place of my regular T/A`s but didn`t really pick up much et, just made the launches more consistent. Your combo should be well into the 13`s with a low 2. to high 1.9`s 60' and over 100 mph even on street tires. I do lower the tire pressure to 15-18 pounds with both the drag and regular T/A`s, otherwise it`s straight off the street.
 
didnt have much time to work on car this weekend but i did get a compression test done. all cylinders are between 165# and 170#. And i got a line on another carb, should be able to do the swap on tuesday.
 
ok i was able to get a summit 750 vac secondary for now (borrowed). I called 4secondsflat.com and talked to them about my set up and got this for recomendations:
Q series 650 mech secondary with airbleed modified
they also recomend a vac Dizzy, said the pro-billet i have does not match my cam specs.
according to them i will not be able to get the right tunning with what i have.
i have been getting so many different sugestions i honestly dont know what direction to go.
 
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