Drivabilty vs. Performance help newbie

-

Bonoz09

Member
Joined
Jul 31, 2012
Messages
20
Reaction score
0
Location
Warren, MI
New here i just picked up member Giggys car and love it heres the basics

340 .030 over (lower end built up by Best Machine)
KB243 .030 pistons 10.2 compression
Edelebrock Aluminum Heads
Edelbrock 1407 750 cfm carb
Straightline Performance cam .540/525 lift and 234/246 dur@.050
LSA 112 , degree to intake lobe 108

Indy Adjustable Rockers

Mopar electronic ignition with Hi-Performance Coil
TTI nickel plated headers
TTI full dual exhaust to chrome tips
Dynomax Super Turbo Mufflers
Espo 2" overstock leaf springs
904 street/strip transmission built by Klem Racing
Turbo Action 3500 rpm stall converter
8 3/4 3.91 rear
P275/60R15 & P215/70R14 BFG Radials on Cragar SS chrome wheels
High volume oil pump
Aluminum radiator

Looking for more streetablity out of it , and wondering which way to go go Smaller cam ? Lower stall ? or both ? and subsequently higher gears necessary to match?

If i could get away with a lower stall and gears and leaving the cam im fine with that if the cam will behave with a lower stall. Considering a TCI 2400-2600 stall ? Currently the car hates going in Reverse esp when cold. and has some idle issues at a stop. I would like to take the car to the Nats next weekend (200 miles of freeway ea way)so looking for some help. I see alot of similar combos and just wondering what your guys experience are like as far as streetability. Would the cam behave alot better with a lower stall or would i just max the issue worse with not enough stall. Also considering either 3.23 w 27in tall tire or 3.55 with the 28'. Not looking for a highway cruiser but i know the current setup inst gonna be friendly as id like and the rear needs to be addressed anyway.

If you think i need to ditch the cam how about a Hughes2328
specs: lift w 1.5 ratio 506/524 , duration @ .050 223/228 LSA 111+3

or one smaller 489/524 219/228 ??

any help would be great !
 
I'd say you have a tune up issue. The cam you have is not very radical and should be easy to make run and idle ok. I hate Edelbrock carbs and would try out a holley 650DP or a 3310. Getting the timing correct will be important as well. I'd start with 18-20 initial,35-37 total all in around 2500rpm. If you feel you must change the cam I'd call Tim @ Bullet and you'll want to be around 220@.050 110lsa for more bottom end power,the huge exhaust split of the cam you have is not helping anything,4-8 degrees is plenty and for what your doing a single will work great. I'd leave the converter and try 3.55 gears with the smaller cam and see if that work for you. If you still want a tighter converter have PTC build you a mild 2600rpm unit. Say no to any shelf TCI converters!!
 
Thanks for the quick response. If you think its more of a tuning issue ill wait to see how well we can get the car running before i ditch the cam. The gears are getting swapped regardless so we'll see how it goes. Any other thoughts and opinions appreciated.
 
You didn't say what you have for an intake, but a dual plane like a Performer RPM would be more street friendly than a single plane like a Victor.

I agree that it sounds like a tuning issue. I like Edelbrock carbs and wouldn't put a DP Holley on anything I wanted to make more streetable. But to each his own.

I agree with the gearing. Try putting in 4.10's and an A518 OD transmission.
 
Ditto the dual plane. Indeed, the very best 4-barrel manifold for low-end manners is probably the Offenhauser "Dual Port", though mixed reviews. A 750 cfm square-bore carb is not best for low end. A spread-bore Thermoquad or Quadrajet would be better, but good ones are rare. Your cam lift is very high, so poor mixing at low rpm. You can tame a wild cam with Rhoads leak-down lifters, and they give up nothing above 3000 rpm. I got a new small block set for ~$25 on ebay.
 
Sorry it has an Eddy Performer RPM intake on it now. So if lift is an issue (and stop me if this is a dumb question0 as im totally new to this and am terrible at cam stuff no matter how much i read. With my adjustable rockers could the "ratio" be adjusted down to lower the lift and help a bit?
 
Sorry it has an Eddy Performer RPM intake on it now. So if lift is an issue (and stop me if this is a dumb question0 as im totally new to this and am terrible at cam stuff no matter how much i read. With my adjustable rockers could the "ratio" be adjusted down to lower the lift and help a bit?

No you can not adjust down the ratio to lower the lift on the cam....and it is not the lift that cause you problem it is the duration of the cam..and the overlap...being that it is 112 LSA help it idle better...but the druation is still going to cause you problems....

and the eddy 750 has a HISTORY of being a POS....Holley 3310....
 
No you can not adjust down the ratio to lower the lift on the cam....and it is not the lift that cause you problem it is the duration of the cam..and the overlap...being that it is 112 LSA help it idle better...but the druation is still going to cause you problems....

and the eddy 750 has a HISTORY of being a POS....Holley 3310....


So do you think the leak down lifters suggested above would help out , sounds like apossibility from the rhoades website reduces both lift and duration at lower rpms ?
 
...........GET ur timing curve set 1st, then adj carb.......rhodes lifters are great; i've used many sets and had all positive results...........kim.......
 
I'd say you have a tune up issue. The cam you have is not very radical and should be easy to make run and idle ok. Getting the timing correct will be important as well. I'd start with 18-20 initial,35-37 total all in around 2500rpm.

Yes to this.

Initial ignition timing will make a big difference in how it runs, especially at idle, if it's not close now.

If the engine has good quench it may not want a lot of total.
 
What oldkimmer said, before you just give up on the build (BTW its not that wild IMO) get the tune right & look into rhodes lifters, I'm not a big fan of eddy carbs with larger cams, I'd invest in a good used holley 750dp 4779.

When you start hopping up an engine & lowering manifold vacuum it changes everything, you can't just exspect it to respond like a stock engine would, you need to re-tune the whole timing curve, i'm sure its a mess & thats why your not happy, get it right & you'll be glad you didn't mess with anything.

I wouldn't mess with the gears neither for now, get the engine right & you'll be happy with the whole combo, it'll be a screamer.

My vote for any changes are these.

Ditch the eddy, get a holley
Get a good adj. MSD dizzy so you can dial in the curve & a 6AL box.
 
Well im taking all of your advice (thanks btw) im going to leave everything alone and start with just tuning the car as much as possible and see where were at. the possible look at the lifters if necessary. I agree that it shouldnt be too bad when running well and that the parts are pretty well matched right now. I'll let you know how it turns out. I'll report back probably next week as I'm having the car dyno'd to help get it sorted out. Again thanks , its nice to get so much help with something new to me.
 
I see you live in Warren just like me. My good friend owns a shop on 15 and mound. Sterling Auto care (not sterling car care on 16 mile). He has been working on mopars forever and builds cars from mild to wild. He helps me out with any car problems. Check him out if you have the time or need any help.

I am having a similar problem with my 70coronet (440 6pack), but I am going to try a higher stall converter first.

Did you check the float level on your carb? What are you ideling at?

Hey where are you getting the dyno testing done?
 
Stock 340 converter stalls about 2400 RPM and that's what I used for the 727 behind my own 340 when I had the transmission rebuilt. If your idle speed is anything reasonable that kind of stall shouldn't be an issue with a properly dialed in cam, carburetor, and timing, especially with the 3.91s masking any overcamming issues.
I agree with other posters, optimize what you've got before you start making changes, although I'd be leaning toward using a Thermoquad/Quadrajet type carburetor (that new AVS type Demon is said to fit square flange manifolds) when you start playing around with axle ratios.
 
Sounds like a good set up, it should run great. Sure the intake gasket isn't leaking and yeah the carb fuel bowl levels are correct ? It needs more timing at idle but limit it to 34 degrees all in
 
Timing FIRST! Put a timing light on it and see where the initial/idle timing is set. If it's not in the high teens or more, it should be.

If you do go to someone and they tell you to total time it that's all you need, RUN AWAY FAST!

If you can live with the manners of that camshaft, I'd keep it. The ignition timing being set well will help with low speed manners. You have a decent stall converter so that helps. Where does it idle in P and in gear?

The ede 750 is not a good carb, no matter how much fiddling you do with it. If you were to consider replacing one item on the car, that's the first thing I would ditch.
 
The carb is the biggest problem. There is no problem with the Edelbrock carbs - when it's the right one. The 1411 is the 750cfm that is calibrated for performance. It would still need to be tunedto your engine, but at least it can be tuned. The 1407 is calibrated for the larger cid factory engines - 460 Ford and 454 GMs and is designed to be very lean. No matter what you do that model will be lean... So I'd say repalce the carb - I'd stick either a 650 Edelbrock or a 680 Street Avenger on it. Scott Brown is Straight Line Performance and his cams flat out work, and Best builds one hell of an engine. So I think it's tuning, and start with losing the economy carb....
 
Well tuned the car, timing is now at 17 initial and 37 all in. Jake from Jake auto helped make things right and its a whole new car. The car made 295 rwhp /296 rwtq , looking forward to getting it to the track. Thanks for all the suggestions.
 
Got thrown a pretty big curve ball shortly after i bought the car. Unfortunately it has to go. Im losing $. BTW the winning buyer just flaked out on me so if anyone is interested lmk. This sucks....believe me i wasnt planning to sell the car a month later and lose money in the process. Life just gets in the way sometimes
 
I saw it, was wondering what happened. I think you meant to say "wasn't planning".

Flaky ebay buyers, no surprise there.

Hope things get better for you. :thumbup:
 
Thanks.yeah it blows pretty bad. I guess i can alwasys buy another down the line.
 
and the eddy 750 has a HISTORY of being a POS....Holley 3310....

The ede 750 is not a good carb, no matter how much fiddling you do with it. If you were to consider replacing one item on the car, that's the first thing I would ditch.

:wack:

I so disagree with you two top guys. Read below. Someone has got it bang on.

The carb is the biggest problem. There is no problem with the Edelbrock carbs - when it's the right one. The 1411 is the 750cfm that is calibrated for performance. It would still need to be tunedto your engine, but at least it can be tuned. The 1407 is calibrated for the larger cid factory engines - 460 Ford and 454 GMs and is designed to be very lean. No matter what you do that model will be lean... So I'd say repalce the carb - I'd stick either a 650 Edelbrock or a 680 Street Avenger on it. Scott Brown is Straight Line Performance and his cams flat out work, and Best builds one hell of an engine. So I think it's tuning, and start with losing the economy carb....

BINGO! 1 word on the Edelbrock 650, go with the AVS style carb. (AKA Thunder Series carb.) Or the Holey, choice is yours.


So do you think the leak down lifters suggested above would help out , sounds like apossibility from the rhoades website reduces both lift and duration at lower rpms ?

Once you get the things tuned up well, yes to the Rhodes coupled with a OD trans if you were to keep it. Good luck with your sale.

Did you list it here and have a price on it?
 
-
Back
Top