Now I know this board is primarly for burning your own chips but it's like catching an advanced class in the middle instead of the begining. I've been reading everything that I can about burning chips and as soon as I can gain a little more knowledge and the equipment I WILL be giving it a try so please bear with me.

Now for the background. A few months ago I installed a Holley 670cfm TBI on my '88 Blazer (full sized, 350/700R4, everything is stock except for the exhaust which consists of the stock manifolds and Y pipe, this feeds into a 3" in & out hi-flo cat then into a 3" in and twin 2 1/4" outlet turbo style muffler with the pipes exiting under the rear bumper), and have been working with Brian over at TBI chips.com. Because of the differerance in the injectors it ran rich from the get go. We've shortened the base pulse width and leaned it out enough so that my BLMs are averaging 128, so far so good. The power is good and on my last road trip I averaged almost 19mpg, again, so far, so good.

The last problem that I an having is a very rich cold-start cycle once the temp drops below about 60 degrees. I'm getting black smoke out of the exhaust and popping in the exhaust from the unburnt fuel igniting.

I *think* that everything else is right given the datalog results along with the performance and mileage.

Now after all that build-up, I'll end it with a simple question. Why is the cold-start cycle so rich, and how would I go about curing it?


TIA

 

He's good enough to seperate people from their money so I'd expect him to be able to fix your chip up just right.

Other then that I'm not going to help you help him earn money off of what I had to work out on my own, and spend hours doing.

Not to mention it was him that got the BCC find site pulled off the net.

Later.

 

Son of a !

My feelings exactly. This is a DIY PROM board, sorry I can't help you out. Maybe if you told Brian to give me the money you gave him I could be of better service.
Seriously though, obviously it's in the chip if it's being rich on cold starts.... so ask him to fix it, don't ask us!

 

You have one of two options.

The first is to keep trying with tbi chips untill they get it right.

The second is to buy some basic prom burning equipment and do it yourself. As youve probably noticed the stock cals tend to be on the rich side and someone who likes to throw in lots of fuel can make this even worse. Jsut as far as fixing the richness at low temps yourself its not hard. If the rest of its off then youll have to really work on that first before you start on the cold idle/open loop stuff.

 

Sheeze, I ask a question trying to get an answer so I can learn how managed engines are controled and get my head taken off for my trouble.. Believe me if I had a clue as how everything worked, I wouldn't have to ask would I? Like I stated in the very first paragraph, I don't have the knowledge or financial resources to burn my own chips at the present time. So for the time being, I'm asking questions when I run into a problem so I can understand WHY the problem is occurning, but this method of learning apparently chaps a few folks cheeks raw. I may be different because I want to understand what I'm doing before I do it instead of just jumping in without a clue.

 

You have the money to throw away on a chip that didn't work.

To get the knowledge means reading, to get the funds might take some sacrifice.

It's a matter of you just asking guestions for him by proxy that's the problem.

If you want to support someone that's torpedo'd the intent of the list, fine, that's your right, but, with your exercising of that right is my right of not wanting to aid those that make life harder on the new guys, like yourself.

You can spend years gathering all the data you want, but until you do something, your not going to actually *get* what making a change does, until you can burn a prom, and item by item see what does what.

 

I always thought this summed it up:

"DIY PROM
Do It Yourself PROM chip burning help. No PROM begging. No PROMs for sale. No commercial exchange. Not a referral service."

RBob.