Gen 7 troubles

[xtrmeta]

Heres an update. When I drive the car when I'm speeding up it keeps popping throught the exhaust. Does it all the time while driving around. Keeps doing it every time I step on the gas to speed up. Crusing at about 3000RPMs is has a slight misfire. The motor is not running smooth.
What would cause these things? Timing or fuel?

[Hammered]

Check your firing order, both wires and in the setup program. Also check your plug gaps. Does your timing table look okay? How did your O2 correction factor look? It sounds more like a timing issue.

[xtrmeta]

The firing order is correct. Both in the wiring and the setup screen. I'm not really sure what the timing table is suspost to look like.
When the car is idling and sitting still it runs great. I can rev it up and it runs smooth all the way through the RPMs.
It only gives a problem under a load.
I also found a blown gasket in the rear of my exhaust. I don't think that had anything to do with the troubles though. It used to blow on the SNC and never caused a problem.
So I'm going to replace that gasket tonight and try it. Just to see.

[DC454]

What do your plugs look like? Do they look fat or lean? Gen 7 DFI or any other stand alone system are never "plug and play". If you have your distributor in sync and the car idles, dyno tuning is your next step. If your new to the system, you might want to pay someone to tune the car. You can blow up the motor trying to street tune your set up.

[xtrmeta]

I plan on taking it to Turbo People for Dyno tuning. I was trying to get it better so I could drive it allittle before it comes off the road.
I'm installing a Procharger on it this winter and didn't want to take it for tuning before it was done.

[DC454]

You need to check if the timing on the computer matches the distributor. In order to do this, pull up the sreen that has the dash board, off on the right of the screen it say's ignition timing. On the bottom of that off to the right it says forced timing. Click that box and it will ask you desired value. Put in 20* and hit set. Now check the timing with a timing light to see if it's at 20*. If it doesn't you'll need to play with the distributor. All of the info is listed in your instruction book.

[Hammered]

DC454: He already synced the distributor in. He's running a program for a like engine provided by Accel tech so he's probably not running as rich as he would be if he was using the initial setup profiles.

xtremeta: The timing table is pretty simple. I'm guessing you should have something like 22-26 degrees at idle (10 initial plus 12 vacuum advance for a similar carbed engine) and 34 or greater at the max rpm, low vacuum (101 kpa - higher numbers mean lower vacuum). Mid rpms and high vacuum should have even higher timing numbers. I'm not a Chevy guy so I don't know what the e-heads would like on your engine. They typically like 36-38 at WOT and peak HP on a Pontiac.

Check your plugs like DC454 recommended. Fouled plugs can cause the symptoms you're experiencing. You might just go ahead and replace them.

I'm guessing you haven't done a datalog yet. At least take a look at your timing and O2 correction factor when you're at a steady rpm and it's popping.

[DC454]

If you have your target air/fuel table set up and the system is in closed loop, you can use the auto calibrate feature in your VE screen.

[68 SuperRam]

I was having the same pop on my car - withe Superram - I changed the plugs - and it solved the problem for alittle while - car runs really rich - itis running really rich - due to problem that I was having with my tranny at the time that Jobe at Turbo People programmed it. Put in fresh plugs before Jobe tunes it for you. He is really cool - he is one of Accel's top R&D guys - I remember him working on and testing the Gen VII system - when I first brought my car to him to program my Gen VI. Good luck.

[jimhamptons]

I plan on taking it to Turbo People for Dyno tuning. I was trying to get it better so I could drive it allittle before it comes off the road.
I'm installing a Procharger on it this winter and didn't want to take it for tuning before it was done.

This is what I am going to do. Jobe is supposed to be one of the best. Let the expert do it and you will be happy in the long run.

[xtrmeta]

I plan on letting him do it. I just didn't want to have to pay for tuning twice since I'll be tearing it down in a few weeks.
As for the plugs there new. The complete motor is brand new. Only has about 20 miles on it so far.
I'm building a new exhaust on it now so it will not have any more leaks. I figured I needed to start there first. Then I'll try some of the tips from you guys to see if they help. If not I'll just start the Procharger install now and get it done and tuned.

[OHCbird]

Have you tried looking at the O2 correction? You've been asked a few times, but haven't posted it.

[xtrmeta]

No I havn't gotten that far yet. I'm working on the exhaust now then I'll take it out and try it to see what it says.
I really appreciate all the help you guys are giving.
I did try to do a data log on it the last time I drove it but I was alone and it was very hard to do.
Is the data log only supost to record for 27 second clips?? Or shpuld it be longer?

[DC454]

Data log can record what ever you set it to. You really need someone else to drive while you work the computer.

[Hammered]

The idea of the data log is so that you can tune the car by yourself. You can set it up to run an hour if you want. You should only need to hit the start key, if that, while you're driving.

[John McIntire]

I too have heard of Job at turbo people, and how good he is. I have also heard that he locks out the ECU so you cant get back into it to change or alter anything, this way you're kind of forced to go back and see him. He does this on 6/7 second cars, might not do it for your street car.

[RSX302]

Heres an update. When I drive the car when I'm speeding up it keeps popping throught the exhaust. Does it all the time while driving around. Keeps doing it every time I step on the gas to speed up. Crusing at about 3000RPMs is has a slight misfire. The motor is not running smooth.
What would cause these things? Timing or fuel?

If you would like, email me your tune and I can take a peek at it. I've gotten pretty good at set-up & tuning Gen 7's.

[email protected]

[xtrmeta]

ronracer,
is that offer still open to take a look at my program. I've been busy and have not had time to get it to you.
I just built a new exhaust on the car so now I need to get it running right.
Thanks

[RSX302]

ronracer,
is that offer still open to take a look at my program. I've been busy and have not had time to get it to you.
I just built a new exhaust on the car so now I need to get it running right.
Thanks

Absolutely...
I just finished tuning a 69 Camaro 540ci with great success. Yea...I was in the car for that so I can't promise you the world, but I can see if I see any major issues.

When you e-mail me, give me your list of components; injector size, engine off fuel pressure, cam profile, compression ratio etc. along with what your having problems with.