So I am having quite a few issues to just getting the motor to run, much less run well. Its at the point I wont drive it to work because I fear it wont make it.

I have been working out some of the basic bugs and felt like I had enough to get it going long enough for VE to do some good.

So tonight I took my latest 've learn and applied it. As small as it was. And decided I would work on my low rpm range 've learns and the issue I'm running into is that it appears to run worse the longer I drive it. It died and wouldn't start at one point I just allowed it to slowly roll down hill and got it started in 2nd after the motor just struggled and struggled with any application of the pedal under load... I believe that because its running so lean that the engine temps are getting greater the slower I drive due to less air movement. And thats causing serious heat sink and other issues. I will test my theory tomorrow without a hood.

I was initally having issues with my timing and belive I have those all sorted.
My base timing is at 23* with the Idle SA matching it.

I am running so lean that I have experienced back firing through the TBI 3 times. pops and gurgles under any load or giving it gas.

Quick basics on this motor would be:

12-256-4 cam shaft
http://www.compcams.com/Company/CC/c...x?csid=91&sb=2
-441 casting heads 73cc chambers, 2.02 1.60 valves
modified throttlebody, running 81lb 454 injectors, 22lb psi spring (i believe) upgraded fuel pump to keep up. (ac-delco EP-381)

goodwrench remanned 350 block.

Manual Transmission.

longtubes, H pipe, Mufflers no cats, 3 wire Heated 02 sensor.

I worried my VE tables are off enough that its not going to run well enough to even correct it and learn any tables.

thoughts?

-J

 

Your cam isn't that big, base timing should be nowhere near that. Your base timing should match your spark reference (Initial SA), meaning wherever you have your harmonic balancer set by hand and with the EST disconnected, your spark reference (Initial SA) in the bin should be the same, usually between 4* & 10* for TBI. Your Idle SA is different, and is fine at 23*...

 

Initial timing is set to ?

What start up bin are you using? I used LO3.ebl.bin and it worked for me.

VAFPR? If not the BPC should be uniform in values. I run same injectors (2560) as you at 21 lbs FP. I think my BPC is around 88 but I use a VAFPR so table varies on BPC.

Can you get engine to stay running by depressing the throttle in neutral at say 1000-2000 rpms?

Are you in CL(coolant over 160dF)? If so take a look at the NB02 voltage...

Fuel pump checks OK?

 

Key on engine off the CE blinks and then stays on?

 

destroyKC is having issues with the TPS & CTS sensors, they are not reporting correctly and change readings quickly. Once the sensor issues are corrected I'm sure that the tuning will go forward.

RBob.

 

Time to check the grounds and ground strap.

Seeing that it is backed to a 4-spd makes me think its an 87 C/K truck or war wagon suburban. That being said it should have a ground up front near the water neck and one on the back of the passenger side head, along with a ground strap between the head and body.

 

Previous to pulling the motor I was having a grounding issue...when the motor went back in I grounded everything with 0 gage.. body to heads, block to frame block to battery battery to frame bat to body... I may have added some additional weight in the wiring alone ahaha.

Fast 355: yes it is an 89 truck. got me.

Street lethal: My Inital SA matches my base at the 23* I have had the timing as low as 14* but it did not seem to run any better, it almost ran worse.

Ronnie: What heads are you running? My 441 casting heads are carb era heads.. I would have to check but i believe the startup EBL bin had an F in the name...have to check when I get home.


As Rbob said, I have to replace a few sensors this evening and try again. I belive I will pull the hood while im at it just to help cool it more while getting this dialed it a bit more.


Thanks for the responses. I will post more after I replace and try again this evening.

 

Your not hearing me. Your base timing is not 23* because your engine would not start, that is impossible. Your Initial SA and Idle SA are two entirely different things. Your cam is very small for your engine, your Base, Initial and Idle SA for a SBC should be as follows...;

Base (by hand) 6*-8*
Initial (in bin) 6*- 8*
Idle SA (in bin) 23*

You said above that your Initial matches your Base at 23*, are you running DIS...?

 

Unfamiliar with DIS.

But I assure you, With a new timing chain, new harmonic balance and a new matco timing light, it is at 23* base. I can try it as low as 6* and If I change the RPM for Idle it might run. previously with a lower RPM idle it wouldn't run on less than 8*

 

Your Base and Initial is for your spark reference, your Idle SA is where your timing advance is at idle with the engine running. My cam dwarfs yours and I am running a significantly smaller engine, and my Base/Initial is set to 12*, with my Idle SA set to 22*. I can assure you that 23* Base/Initial is too much, and that your either explaining it wrong, or your just confused by it. Either way, take care of your sensor issues and see if that fixes your problem...

 

I am going to venture that he has an aftermarket balancer and timing tab. If TDC is not precisely verified with a dial gauge during short block assembly the timing tab 0 deg position and balancer slot relative alignment do not represent actual TDC. On more than one occasion I had to cut a new line on the balancer outer diameter to match timing tab 0 deg.

DestroyKC can you please photograph your balancer and timing tab position at #1 cyl TDC. Do you know make of your balancer????

//RF

 

Pictures coming soon. While the cam was going in last week I double checked my timing gear was keyed correct. And during this time I did install a new harmonic balancer.

The balancer is made by proform.

This morning I pulled my distributor reser back to tdc on the exhaust stroke of cylinder 1. And re stabbed the distributor and checkd my wires.The 0* on my timing tab matched up with the 0* on my balancer which is marked up to 40*

It won't even start if lower than about 18* it just cranks and cranks... but won't start. its set back to sa 18* sa idle 24*

Sensors are now fixed and its throwing no codes. Tonight when it cools down ill take it for an hour test.

 

Forgive me, but isn't 0d TDC supposed to be when BOTH Intake and Exhaust are Closed on #1? That's the way I have always set my distributor after having installed a cam.

 

Yes, TDC is on the compression stroke not the exhaust stroke. It appears that he is trying to set #1 cylinder TDC with #1 with his distributor's rotor essentially when #6 cylinder is at TDC, so his distributor is off 180 degrees, and he is retarding timing that much so that it will catch and run based off of #6 cylinder. He needs to set TDC when both valves are closed on #1 during the compression stroke, then set distributor rotor to face #1 on the cap, then set base timing to under 10*...

 

Thats exactly where I am at. On the compression stroke. Tdc with a feeler gauge. Set dizzy to cylinder 1.

It will just turn over and turn over unless higher timing. It will run at a lower timing, but it wont start that low.

 

What size Proform balancer are you running, diameter wise...?

 

6-3/4 Inch Diameter- 8.46 Pounds- Internal Balance - Nodular Iron



Mine is marked already on the balancer just like in the photo above. When im at TDC, my timing tabs 0* matches 0* on the balancer.

 

No longer throwing Some codes but what you see here I'm curious about. Iat sensor and est which I believe is new. Ignore the vss code Speedo has not worked since I got the vehicle and I have replaced the sensor x2

 

Boy, the kPa looks like you are in Decel.

 

I was coasting down hill slowing down when I took that pic.

 

Which timing chain cover and timing tab are you using?

Do you have a pic of the whole setup at TDC?

 

I can get one tonight when I get home.... here is the tab but its not at tdc here. Shitty in a but the only one have on me right now.

 

Timing chain cover was a swapmeet special. Timing Tab I couldnt tell you, I do remember having to paint the tab. it was originally black. It came from the garage, possibly off the old block. Possibly another swapmeet... sorry.

 

It's starting to sound more and more like you have the timing set where its' supposed to be, around the 8* mark, but the tab and balancer markings are off and not embellishing the true TDC, which is why you think your at 23* when your really not...

 

The correct position of the timing tab on the cover is dictated by which balancer is installed on the crankshaft. The stock GM balancer from 86 and up is marked so that it needs the tab at about 12 o'clock. Earlier balancers had the TDC indication mark more in the CW direction - they need the tab at about 2 o'clock.



In your case get the ProForm Tab p/n 141-200 from Summit (or elsewhere)



From the photos the Proform tab moves 0 deg position further counter clockwise - toward center of the engine unlike your existing swap meet special tab. At least you'll have a matching Proform parts, although I never hold my breath when it comes to ChiCom made parts.....

Action items:
1) Get Proform tab
2) Compare position of 0 TDC vs Swap meet special tab

//RF

 

As promised. Here I am at tdc on my compression stroke. My timing tab matches my harmonic balancer.



Still at tdc here is my dizzy. Pointed at cylinder 1.



My timing chain was set with the cam sprocket with the "o" at 6 o'clock matching the "o" at 12 o'clock on the crank sprocket. Here is an image on the crank sprocket showing what channel I'm in.




Closes double roller chain.
And yes in the image I still had to rotate the crank to get the "o" to 12o'clock

 

Found some receipts. Its a professional products not a proform.

Link
http://m.summitracing.com/parts/pfs-80000

 

Your running a GM cam sprocket (3735412) with a comp cams retainer, and your saying that your pointing the dots at each other (6 o'clock cam, 12 o'clock crank) to attain TDC for number 1 cylinder, and that is your problem. Factory timing chain gears point up, so your dots should both be at 12 o'clock...

 

Yep, you run a straight edge thru the crank snout and cam to line up the dots.

 

Install the gears dot-to-dot, then rotate the engine one full revolution to bring it to TDC #1 (both dots at 12 o'clock).

RBob.

 

Install the gears dot-to-dot, then rotate the engine one full revolution to bring it to TDC #1 (both dots at 12 o'clock).

RBob.

 

Whats throws me off is thats its a double roller timing chain.I found the camshaft gear for the cloyes set thats on the motor now. My friend who was "helping" me reassemble the motor assured me that using the gmail stamped top gear to replaces the top cloyes gear would be no different. The reasoning behind that being the gm stamped one did appear to be higher quality. I will take it apart tonight and swap out that gear.... in looking at the cam pin hole. It doesnt appear to be located in much of a different spot. By memory though who knows.



Curious though. I can't recall my current timing gear having that raised post in the center. I may just purchase a whole new set...

 

If that top gear was factory. It wouldnt be a double. I have the factory still here. So could two aftermarket cam shaft timing gears have different cam alignment pins in comparison to the marking dot?

 

Listen, from the first picture you posted, you have a factory double roller GM cam sprocket, the casting numbers underlines it, as well as the letters GM. Factory timing chains will have a 12:00/12:00 TDC for #1, and most if not all aftermarket timing chains will have a 6:00/12:00 TDC for #1. Bring your TDC to number #1 by putting your finger in the #1 spark plug hole and feeling for compression, pop your distributor cap, notice the rotor facing number #6, unbolt the distributor clamp, pull the distributor up (not out) just enough to rotate the rotor to face #1, set it back down, bolt down the clamp, hook it all back up, and restart the engine...

 

If you look at my pictures from yesterday morning. I did just that. And when I pop the cap the rotor is pointing dead at cylinder 1. I will be replacing the timing set tonight and tomorrow to eliminate the possibility of error.

 

Again, this is YOUR picture from yesterday morning,you have the dot on the GM double roller cam sprocket at 6:00, it needs to be at 12:00. How can you not see this?

 

I understand and will be correcting that this evening. But I must have missunderstood you previous post. I took from it that you were saying. In my current wrong configuration that if I rotated cylinder 1 to tdc on the compression stroke. Pop off my cap. That my rotor would be pointing at cylinder 6. Thus confirming the error in my timing gear alignment....

What I was replying was that when I do that. Its point in right at cylinder 1.

I was not saying my timing gear was correct and thats why I said I will be coffee it this evening.

I will post up once I have done so and start her up.

Seriously lethal I am hearing and appreciative of your advice here.

 

Always remember that your camshaft controls your timing events. The crank will always have number 1 and number 6 at TDC at the same time, but the camshaft controls which one is on the compression stroke and which one is on the exhaust stroke. If you originally lined up the dots at 6:00/12:00 but set it to number 1 by accident instead of number 6 then there is no reason to remove the timing chain cover again to fix it. Just bring the line on the harmonic balancer to 0 on the tab, lift the distributor, and rotate the rotor 180 degrees. So if it is facing number 1 face it towards number 6, or vice versa, that will take care of it for you...

 

Took the distributed out and went 180* and was rewarded with massive backfires and pops no mattwe how I advanced or retarded it but never would fire up.
. Even the
Occasional pop through the tbi.

Going to take the timing cover off and go back to square one of timing. Timing chain replacement and re adjust the valves and re stab the dizzy.
I really appreciate tge advice here and will repost when done. Figure friday evening I'll fire her up again

 

Don't forget to go back into the bin and change back to original settings, you have to put Initial SA back from the 23* that you set it to back to a more stock oriented 8*, disconnect the EST and set Base timing by hand to 8*. You can keep Idle SA at 23*...

 

I was chasing my tail for awhile earlier this year due to me not paying attention when editing my bin lol. The Initial SA and Idle SA are right next to each other. I went to set my Idle SA to 22 degrees and set my Initial SA to 22 degrees by accident since they're right next to each other and both start with "I". I felt pretty dumb once I caught my mistake.

 

I missed this the first time around, the crankshaft is not in the correct position for installing the chain. The crank key-way needs to be at approximately the 1:30 position.

The reason is that the crank key-way is exactly in line with the #1 rod journal. So it needs to be at 1:30 in order for the #1 piston to be at TDC. IOW, need to rotate the crankshaft about 90* clockwise.

Also need to figure out which key-way relates to which marker on the crank gear.

RBob.

 

Wheb I installed it I had they key about like you said. And the "o" os 0* and was at 12oclock

 

The stud or little bearing thing on the front of my timing gear is keeping the cover from going on..

 

Made clearance with a socket of approx the same size and a ball peen hammer..

 

Happy labor day for all you who see this tomorrow!

 

Those 3way crank gears are for installing the cam from retarded to advanced and in between. Gotta be attentive to that.

 

The piece on the front of the upper gear is to retain a roller cam. It prevents it from walking forward. Flat tappet cams don't walk as the lobes are tapered.

The end play needs to be set so that the cam position is retained.

Don't forget to rotate the engine one full revolution to put both dots at 12 o'clock. That will be TDC #1.

RBob.

 

Well gentlemen. New timing chain and gears. Meticulous installation and procedures for setting valve lash and dropping in my distributor.

And back to square one. Same issue. 20* to start. Backed her down to 14. Adjusted initial sa to reflect in my base. And she will turn and turn for 15 seconds but won't fire up. It did however backfire through the carb once. But only once In about 6 tries.

I did notice the injectors were firing in a slow pulse. About matching the turn over rate of the motor.

I could the issue be a wrong sa table for my heads? Somewhere else in the programming?

 

ZIP and post both XDF and BIN file together.

//RF