New engine gremlins - frustrating

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i can't see the secondaries opening at just tip in with NO spring in the secondary's. I have a 850 DP and it only has 31 squirters.
I think your float levels are low(not set were they belong) when you tip in or just start to open the throttle, the squirter is not filling in the fuel hole with a squirt. A bigger squirter will only make that worse.
With the eng off, just barely and i mean touch the throttle...............there should be fuel from the squirter. If there is not, you need to raise float level or squirter arm is not adjusted to 0 play(that's now how you adj it but is the way to see if it is not adj right!
 
I wonder if should go the other way with the squirters. Carb comes with .035 and maybe step it down and see how it reacts. The kit comes with only 1 lower .031
 
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They said to drop the squirter to .31 and if it still bogs that it's too much carb and to go with 600 cfm, but not too increase the squirter on a 6,000 rpm 360 engine.
 
TRWRacing said:
Maybe stiffer spring for the secondary? Possible that it's opening too quick causing the bog? If so, does anyone know if it uses the same as the Holley kit? I don't see one specific for the Summit carbs.
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That was sort of the thought.... Not that it is opening too soon but that it may be opening just a bit for a moment when you add throttle at low RPM; the vacuum is already low under those conditions. I'll suggest it again: observe where the vacuum levels are going so you can get some data. That is one way in which to look for more data on exactly what is happening, rather than just throwing parts at it. Kinda similar to looking at an AFR meter......it's using test info to guide your changes.

It will also help you see if the power valve may be blipping open due to momentary low vacuum levels.
 
TRWRacing said:
Plenty of time was given to the shop to complete this while the weather was good. I really don't feel like paying the labor to readdress this next summer. I will fix the heater core then. My feeling is this should have taken 2 weeks not 10.
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Yeah, 10 weeks is a bit too much.....
 
Mechanic says timing is at:
is set at 7 degrees which puts the total at the desired 36 at 3000 rpm.
 
Mopar Sam said:
Fix the timing curve before messing with the carb.
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The distributor was curved by MRL since it came with the installed with the engine. How did this change just by removing the distributor to install the engine.

This was supposed to be close to turn key. I get turning the carb, but not recurving the distributor.
 
I'm new to the performance side. How does this affect the distributor springs? I get a change in the initial timing, but how does it change the mechanical advance with r/r of the same distributor?
 
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On that leaking heater core, old heater cores aren't intended for high rpm, so you might want to look for a restrictor off the heater inlet on your intake. Ask me how I know.
 
TRW, removing the dist. should have no affect on the curve. If the slots in the dist. were welded up , maybe the weld did not stick. Also, remember, a dyno is not a car. A tune that works on a dyno may need tweaked for best performance in your particular car. Your car is telling you it wants more initial timing.
 
Ok. To make sure I relay the correct info. Total adavance is 36 degrees at 3000 rpm with the vacuum pot disconnected. Increase intial timing to 14-16*. Permanently leave the vacuum advance disconnected and not run it?

Test drive. If good put back original squirters .35
 
Breaking an engine in and basic tuning on an engine dyno has little relation to the engine in your car. For starters te dyno doesn't pull the engine down starting at idle like a real car does. For another the engine was not dyno'd with manifolds, an air cleaner, or in many cases any parasitic loss. So ignore the specs it came to you with would be my direction. I think there are some issues and here's how I'd approach it:
Initial should be higher - at least 12 degrees, and probably closer to 16 would be better.
Total without vacuum is fine at 36 for now. IMO, it should have the vacuum advance functional.
The rate of advance needs to be slowed down because of the gearing and convertor. Bring in the mechanical advance all in by 3K. It's probably all in by 22-2500.
Put the OEM squirters in the carb. you should not need anything more than .31s, and by going larger you've set yourself up for a lean condition when the pump runs out of volume.
Get a vacuum gage and tape it to the windshield so you can see it when driving. Stick it on the ported vacuum nipple and go for a drive. Determine what vacuum levels the engine has at light throttle cruise, and idle in gear. Then replace the power valve with one that is 2" lower than the idle vacuum reading.
Set the floats per the Summit instructions.
 
moper said:
Breaking an engine in and basic tuning on an engine dyno has little relation to the engine in your car. For starters te dyno doesn't pull the engine down starting at idle like a real car does. For another the engine was not dyno'd with manifolds, an air cleaner, or in many cases any parasitic loss. So ignore the specs it came to you with would be my direction. I think there are some issues and here's how I'd approach it:
Initial should be higher - at least 12 degrees, and probably closer to 16 would be better.
Total without vacuum is fine at 36 for now. IMO, it should have the vacuum advance functional.
The rate of advance needs to be slowed down because of the gearing and convertor. Bring in the mechanical advance all in by 3K. It's probably all in by 22-2500.
Put the OEM squirters in the carb. you should not need anything more than .31s, and by going larger you've set yourself up for a lean condition when the pump runs out of volume.
Get a vacuum gage and tape it to the windshield so you can see it when driving. Stick it on the ported vacuum nipple and go for a drive. Determine what vacuum levels the engine has at light throttle cruise, and idle in gear. Then replace the power valve with one that is 2" lower than the idle vacuum reading.
Set the floats per the Summit instructions.
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in addition to the above, take a harder look at your pump shot after warm up, w/ maybe heated gasoline helping to cause a lean condition, w/ too little pump shot.?????????? fuel or timing related, one of the two.
 
Going to look at the car today.

I got a reply from Turbo-Action which I contacted them regarding my spec and vehicle use regarding the torque converter and there reply was:

"We would not have recommended a 11" for your combination. Assuming your
cam is a small hydraulic we would have suggested a 17805ST 3000-3500rpm
stall. If it was a medium to large solid lift or roller cam, we would
have suggested a 17805SMED 3400-3900rpm stall. Your torque curve is
very flat over a wide range and should be excellent with either
converter. You may have some other issue in vehicle if you have one of
the above converters. Yes a converter could be defective, but we have
less than 1% failure with those we would have suggested. If you have
one of our 11" or any other company, your performance would be bad."

Well, I did not purchase it blindly off their website.

Not happy, this is exactly what I was trying to avoid while buying a TC. Spent $555.45 on the torque converter based upon their recommendations to avoid bad performance and not by an off the shelf Jegs model. I will try and see if I can get the paperwork from the installer. I gave Turbo-Action a copy of the CC statement proving that I bought it from them on 8/31 and purchased via the phone based on their recommendations.

First I will get timing/carb bog issue addressed, but the TC will not be looked at until the spring and I don't feel like wasting $555.45 plus the labor to change it out.
 
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TRWRacing said:
It stumbles/chokes to almost dies, pops back through the carb and takes off.
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that sounds like a lean fuel mixture condition.
i would jet up two sizes, reset idle mix and then see how it acts.

that's assuming your accel pump linkage is tight. as in, the slightest movement of throttle will move the accel pump arm too...check this first.
 
Just because the keyway lined up when you restabbed the dist doesnt mean the housing didnt rotate. Especially when tightening the hold down.
Sounds like you need a new shop hehe.
 
I doubt it but will check. Problem is partially with communications, people listen to reply and not to understand.

Hindsight is 20/20, not sure if I would ever do this again.

Car salesman, torque converter rep and the engine replacement has all been much to be desired. Too much BS. I'm sorry just being blunt and 1 year of ownership frustration, engine bad after 6 months and was in storage for 4 months.
 
Obviously there's more to this car's story with you than just the tuning issue. I can appreciate your frustration. It is very common for tech lines to be staffed with people who follow direectives to steer buyers to certain things, and to be poor listeners. It's also common to find different opinions from anyone involved.
You just stated "people listen to reply and [not to] understand". You are getting some solid responses around tuning possibilities to look into, and yet you are looking at a convertor problem. No convertor, in and of itself, will be such a hinderance to an engine that it dies or pops. Factory convertors are 11" and 1400 stall and if you had a bone stock one, it might be sluggish, but it wouldnt pop or have running issues. It just wouldn't accelerate the car very quickly... Your TA is a 2500rpm unit... the issues have nothing to do with any convertor.
Your issue is tuning, and it's probably best to not go back to the guy you took it to because he's not familiar enough based on his work. This is just what everyone that doesn't have EFI has to do and when these cars were new they got it done seasonally. So have some patience with yourself.
 
I understand. I apologize just venting. It will be resolved. I am just fighting the weather to get it home.
 
No apology needed. I've thrown tools, broken stuff, and yelled at all kinds of living creatures (friends, loved ones, dogs, cats, squirrels, horses, turkeys...). If you're new to it, get a couple books on carburetor tuning and read up. The two most important things I ever learned were timing effects carb, carb doesn't effect timing so do timing first; and more fuel is not usually the solution, even if it takes care of some of the problem. It's the right amount of fuel, at the right time that makes it all work best for power and economy.
 
TRWRacing said:
Mechanic says timing is at:
is set at 7 degrees which puts the total at the desired 36 at 3000 rpm.
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Hmmmm, these numbers look off. What is the mechanic's source of information for this total advance number? Is he measuring these numbers or going off of some data sheet or what? That is 29 degrees of total mechanical advance which is much higher than usual for these distributors in a performance application, so these numbers need some examination. Total mechanical advance of <20* is common. You reported 18* initial advance in post 8 per MRL, so the whole thing is not hanging together.

From your description, it sounds like the local mechanic measured this right (with the vacuum advance disconnected), but I would recheck this 1st thing because the numbers do not sound right. I would be expecting initial advance to be well in to the mid- or uppper-teens and the full mechanical advance at the mid 30's. (Which is what was reported in post #8.)

If this distributor does indeed have 29* of mechanical advance, then if you just simply increased the initial timing to 14*, you would be risking engine damage at RPM's beyond around 2000-2500 RPM . If you did so, then the total mechanical advance would be 43* which is far too much total advance.

Have you re-asked MRL what numbers they curved this distributor to? No judgement can be made about what they set up without speaking to them. I would do so ASAP.

And as for the vacuum advance hose ( assuming it has one), is it plugged in to the side of the carb, or down lower to the manifold?

Do you have a timing light to check the advance numbers yourself?
 
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The mechanic was checking the timing with vacuum advance connected with initial set at 8*
Right now it is set to 17* intial with 36 total at 3,000 rpm. Vacuum advance is disconnected. It will be run that way for now and confirm the carb tune.

I have the builder documentation confirming this.


I confirmed with the builder (MRL)
Timing per the engine builder:
On Monday, November 21, 2016, 5:19 PM, MRL Performance <[email protected]> wrote:

That's not right. He must have the vacuum advance hooked up. There is no way I have 29* of mech advance in the dist. Check total at 3000rpm with the vacuum advance disconnected. It should be set to 34-36*.
 
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