Strip to Street Help Needed

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I agree with others. Sounds like some timing and/or carb tuning issues. That really should be a decent cruiser with that cam. I'm running a bit more cam than what you have on my street/strip ride, but I have the idle set to about 1200 rpm and drops down to about 800 in gear. Takes about 2-3 minutes to get it to idle on it's own from a cold start. And DON'T start messing with timing without a light!
 
Skep
Your way will work, for experienced tuners,taking short-cuts to find the perfect tune.
But for a guy without a lite,and no tuning experience, its a recipe for disaster.

clinteg
A 400 rpm drop from N/P to in-gear is a pretty big drop. Without knowing your combo, I hesitate to say it, but it does seem that something is off.
 
Post #2

Get a light and time the car to about 20* BTDC for idle timing. If you know where the total number needs to be, simply math to adjust mechanical. If the car was timed using the often, but not the best for street car, total timing method, that could be part of your idle issue. Lack of initial timing.

Simple test, warm car up, give distributor a twist CCW. If it picked up rpm, the engine wants the timing at idle. Reset idle speed and repeat until it doesn't pick up. See where that number is using timing light.

See where the starter kicksback when warm to find you high side idle timing point. That's the cruz of skep's post.
 
AJ/FormS said:
clinteg
A 400 rpm drop from N/P to in-gear is a pretty big drop. Without knowing your combo, I hesitate to say it, but it does seem that something is off.
Click to expand...

I could be wrong on that. RPM jumps around at idle in gear so it's really probably hanging around 800-1000. It's a healthy cam 266/272 @ .050 and a 106 LSA and .645 lift and it's fairly lopey. I have to touch the pedal sometimes to keep it going. I've tried tuning it, my engine builder tried too and we just couldn't get it perfect. The AFR is on target too. He thought that it was something to do with the distributor getting out of whack somehow at low lopey idle because the carb seems to be spot on. It's the same carb (Holley 950HP) I used before and it was always reliable and had a perfect idle. What's wierd though is that if I hit the brakes hard, it will kill the motor. Explain that one to me.
 
Oh, now dont be bashful. 266/106 and fairly lopey?Fairly?
I new something was off...my thinking was off.
The biggest cam I ever tuned was the 292/509, which they say is 248@050. That cam I would say was fairly lopey.That was fairly simple to dial in.
Your cam,at some 18* bigger, Ima thinkin, fairly, is being modest! Ima also guessing that would be a stroker?That would be almost the only way to make it docile enough for to run it on the street.

As to the stalling while braking, I'm sure you've tried everything, but I'd like to throw a couple of things at you;
If it happens while stopped, in gear, and braking, its probably a bad booster.If you dont got one, then IDK.
If it happens while coming to a stop, I would suspect a high fuel level, and or fuel slosh, assuming the timing is close to correct, and the TC is not too tight.
Just throwing stuff atcha.

Heres a test for you.Take her out, fully warmed up, and hit the brakes to stall or nearly stall her out.(proving the issue still exists)
Next,if you have a booster, defeat it, and now repeat the test.If it still stalls, I'd go with the high float level/slosh idea. But if it doesnt stall, I suspect the booster.
I should also mention, And bear in mind I've not tuned a cam as big as yours, that there is such a thing as too much idle-timing. What I have found with too much idle-timing, is, its possible to get the t-blades too far closed, and running into a sync problem between the transfer slots and the idle discharge ports. Then when the blades slam shut on decel,under heavy braking, and the fuel stacking up on the front of the bowls, the carb goes momentarily lean,just enough to cause a stumble or a stall.The same thing can happen on a 4-corner idle carb if the secondary mixture screws are pulling a too-high share of idle fuel.
To cure this, pull the carb off and flip it over. Check the sync. The T-port should be slightly rectangular(best), to square.If its not, that could be the problem. You will want to make it so, and bolt it back on.From this point on,try to leave that curb-idle screw alone. Adjust the idle speed using other methods; such as secondary cracking, and initial timing, or an idle-air bypass circuit. Reset the idle mixture screws as may be required. This is part of how I tuned the 292 cam. It idled at 850 easy enough, and took anything I could throw at it. It had a V-can hooked to the spark-port, and it liked a ton of vacuum advance, to smooth it out off-idle and under part-throttle.Your cam is several sizes bigger,( probably around 310 to 315? advertised), so your results may vary.
I suppose you've been down this road,and I've not said anything new. If so, just ignore me. I'm just trying to help. I hate a stalled engine in traffic! More so if its flooded.
 
Thanks for all the input guys. After digging into the car a little more, I realized that there is no thermostat, and that the previous owner drove it around with the choke closed most of the time as it's manual and he had no cable. It was his son's car, but he passed away and dad was taking it out every week to keep it running. I'm guessing dad never realized and thought it was automatic. I pulled the carb and gave it a good cleaning. I have a timing light but also wanted to establish TDC as I don't trust the marks he made. Looked like from the balancer he was shooting for between 34 and 36deg total timing but I have no idea what the initial is yet until amazon delivers my TDC bolt tool and marking tape......to be continued.
 
Got my Collectors insurance from Haggerty on Thursday, plates from the DMV on Friday no emissions or inspection needed.
 
search hillbilly timing tape. Never need a timing tape.
 
AJ/FormS said:
Oh, now dont be bashful. 266/106 and fairly lopey?Fairly?
I new something was off...my thinking was off.
The biggest cam I ever tuned was the 292/509, which they say is 248@050. That cam I would say was fairly lopey.That was fairly simple to dial in.
Your cam,at some 18* bigger, Ima thinkin, fairly, is being modest! Ima also guessing that would be a stroker?That would be almost the only way to make it docile enough for to run it on the street.

As to the stalling while braking, I'm sure you've tried everything, but I'd like to throw a couple of things at you;
If it happens while stopped, in gear, and braking, its probably a bad booster.If you dont got one, then IDK.
If it happens while coming to a stop, I would suspect a high fuel level, and or fuel slosh, assuming the timing is close to correct, and the TC is not too tight.
Just throwing stuff atcha.

Heres a test for you.Take her out, fully warmed up, and hit the brakes to stall or nearly stall her out.(proving the issue still exists)
Next,if you have a booster, defeat it, and now repeat the test.If it still stalls, I'd go with the high float level/slosh idea. But if it doesnt stall, I suspect the booster.
I should also mention, And bear in mind I've not tuned a cam as big as yours, that there is such a thing as too much idle-timing. What I have found with too much idle-timing, is, its possible to get the t-blades too far closed, and running into a sync problem between the transfer slots and the idle discharge ports. Then when the blades slam shut on decel,under heavy braking, and the fuel stacking up on the front of the bowls, the carb goes momentarily lean,just enough to cause a stumble or a stall.The same thing can happen on a 4-corner idle carb if the secondary mixture screws are pulling a too-high share of idle fuel.
To cure this, pull the carb off and flip it over. Check the sync. The T-port should be slightly rectangular(best), to square.If its not, that could be the problem. You will want to make it so, and bolt it back on.From this point on,try to leave that curb-idle screw alone. Adjust the idle speed using other methods; such as secondary cracking, and initial timing, or an idle-air bypass circuit. Reset the idle mixture screws as may be required. This is part of how I tuned the 292 cam. It idled at 850 easy enough, and took anything I could throw at it. It had a V-can hooked to the spark-port, and it liked a ton of vacuum advance, to smooth it out off-idle and under part-throttle.Your cam is several sizes bigger,( probably around 310 to 315? advertised), so your results may vary.
I suppose you've been down this road,and I've not said anything new. If so, just ignore me. I'm just trying to help. I hate a stalled engine in traffic! More so if its flooded.
Click to expand...

Hahaa I'm laughing! Yes it's about as extreme as I want to go on cam for a car that I drive on the street as much as I do. And yes it's a stroker so it eats up that duration. It's a manual brake car, mechanical advance on the dizzy, the floats have been set properly, it happens whether I get fuel slosh or not, and TC is an 8" 5500 stall. I'm not real familiar with what you've said about the carb sync and all that, but what I did understand some of the logic. One thing I'm going to try first is stiffer springs on the advance. It comes in early and with my TC, there really is no reason for it to come in way early. I'll start there and head to the harder things. A quick throttle bump keeps it going so it's not bad, but it's not right. Appreciate the help.
 
clinteg
Well with a 5500 stall, I imagine, the engine wouldn't care much, how soon the timing came in. However if the advance was to stick full on as the engine returned to idle, AND the port sync was off, I can certainly understand the engine complaining about it by stalling.Lots of guys run locked dizzys with combos like that, but it still requires a reasonable port sync to pull it off.And theres no harm in slowing it down.
I suppose you have eschewed the PCV install, and are just running VC breathers
In the past I have used the PCV port as a continuous, idle-air bypass.
If I were a betting man, Id put money on the port sync.
 
AJ/FormS said:
clinteg
Well with a 5500 stall, I imagine, the engine wouldn't care much, how soon the timing came in. However if the advance was to stick full on as the engine returned to idle, AND the port sync was off, I can certainly understand the engine complaining about it by stalling.Lots of guys run locked dizzys with combos like that, but it still requires a reasonable port sync to pull it off.And theres no harm in slowing it down.
I suppose you have eschewed the PCV install, and are just running VC breathers
In the past I have used the PCV port as a continuous, idle-air bypass.
If I were a betting man, Id put money on the port sync.
Click to expand...

I'll look into that. Wish I had someone close that could help me out as I don't really know what I'm doing with that aspect of the carb. A little research will be in order for sure.
 
clinteg
Are you in some way handicapped. I ask this in all seriousness, because I sense a very great hesitancy on your part to even pull the carb off and flip it over. Feel free to PM me and I'll walk you through it.
 
AJ/FormS said:
clinteg
Are you in some way handicapped. I ask this in all seriousness, because I sense a very great hesitancy on your part to even pull the carb off and flip it over. Feel free to PM me and I'll walk you through it.
Click to expand...

Not at all. I just won't know what I'm looking for until I physically take it off and look at it. I'm not hesitant to take the carb off. I've stripped the entire car down and rebuilt it front to back. A carb is nothing to take off. It's the functionality part of it is where I get hesitant. I'm just saying I wish I had someone around to show me while I have it off the car, what part does what. I know what the general parts and what they do, but not much beyond that.
 
trevorcrum said:
Thanks for all the input guys. After digging into the car a little more, I realized that there is no thermostat, and that the previous owner drove it around with the choke closed most of the time as it's manual and he had no cable. It was his son's car, but he passed away and dad was taking it out every week to keep it running. I'm guessing dad never realized and thought it was automatic. I pulled the carb and gave it a good cleaning. I have a timing light but also wanted to establish TDC as I don't trust the marks he made. Looked like from the balancer he was shooting for between 34 and 36deg total timing but I have no idea what the initial is yet until amazon delivers my TDC bolt tool and marking tape......to be continued.
Click to expand...

Hopefully that didn't go on for too long I'm sure the oil was in terrible shape, great way to kill rings too... If you haven't already done so change the oil, if you did it a while ago check it now and see if it smells like gas. Also put in a 180* T-stat, get it up to proper temp and have someone outside the car watch the exhaust for any blue smoke as you drive around. Having the choke stuck closed and no thermostat is like a double-whammy to your upper cylinder walls and overall engine wear.

BTW timing tape likes to fly off, my "permanent" fix is to cut small marks with a Dremel going up to 50* or so by rotating the crank 10* at a time and reading off the timing cover tab. Checking TDC is a good idea too.
 
Thanks all for the help everyone... After an oil change, coolant flush, re aligning TDC, plug change, upgrading to a Summit RTR distributor, new wires, and a Blaster 2 coil, the car is now at initial timing of 20, and total around 34. It's starting and hitting idle almost immediately, and seems much smoother.
 
trevorcrum said:
Thanks all for the help everyone... After an oil change, coolant flush, re aligning TDC, plug change, upgrading to a Summit RTR distributor, new wires, and a Blaster 2 coil, the car is now at initial timing of 20, and total around 34. It's starting and hitting idle almost immediately, and seems much smoother.
Click to expand...

:cheers: good to hear, how do you like that distributor? I've wanted to upgrade my factory electronic dizzy for a while i never liked the 'trial and error' method for tuning the advance curve with those slots on the advance plate.
 
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