Thread: New build sbc 383 break-in

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For my SBC plans those that have been following the build know that I am weeding threw EFI systems and what would work best taking into account all the suggestions that have been provided.Educating myself.

Pat advised me to be careful about rich situations washing down bearings and ruining engines.I do listen to him.In fact it brought to mind that the reason behind this build is I bought a V8 donor Astro van and during a reseal/inspection of the engine I found the rod bearing where almost shot.This is a crate short block with less than 100,000 miles on it.The previous owner I think during the V8 swap just extended the injector wires,added 65lb cop car injectors lifted and never did a chip burn.It is now the only thing that makes sense.

So I am in the process of building a 383.The thought occurred to me that sometimes tuning these EFI's there is some trial and error.Certainly not the best thing for a new build engine.

So here is what I am thinking.How about doing the break-in setting the rings etc with a carb set-up??.Then after I feel the break-in on the engine is complete,then install a best case EFI.

Pat and anyone else your input is certainly welcome.

Thanks

Oh I am thinking of a Edelbrock performer intake with a Edelbrock 600 CFM vacuum secondary's and a HEI dizzy.Any comments??.

Well this thread worked out well.

Honestly folks-if you tell me I am crazy it doesn't matter.It would help...............

I'm sorry Gary, I didn't know you were sitting up all night waiting on an answer---

However, If I had known you were wanting to run EFI, I would have suggested that you go LT1 from the get go---

The carb set up will work for break-in but then for fuel injection you will need to change the whole fuel system as fi is much higher pressure than a carb can work with

Jerry,you know how genus's work.Wake up in the middle of the night to write down a idea...............I'm not one of them.Just a guy that knows how to spend money on a project like a drunken sailor.

Point well taken about the FP and FPR.I do have both fuel tank pick-ups.This one is unusual because it is out of a 1985 Astro 4.3 which was the only yr that had a carb.




The other one is in the Ole Yellar 1989 van which is a TBI in tank pump.From what I have been studying about EFI's it's not enough for a high pro EFI and will require a external FR and a higher FP.

I am guessing that I would spend a easy $500 for a carb set-up(carb,intake,HEI,and fuel system) that once I was done with it I would sell off.I am that nervous about damaging the 383 during break-in with trying to tune a EFI,that I am thinking it is money well spent.I am not sure,I could be here over cautious about that.

I am also thinking there shouldn't be any towing during break-in,just light driving.

If an EFI is in your future, why not just buy a Holley or FAST self learning EFI setup instead of a carb and intake setup. I know they run about $2000 but the cost of a carb, intake and HEI is not trivial either.

I put a Holley HP EFI on my 355 and it is a running fool. There will be none of the worries you have with rich issues and the performance and milage will be better.

Just sayin'

Bob

Bob-I would be concern about the tune being right and if it would pollute the oil with gas while I got it dialed in.I admit I could be totally off base in that thought.It is just such a critical time during engine break-in.

Gary

Because either system has a wide band O2 sensor, they are programmed to start just slightly rich like any EFI system and then run at 14 to 14.5 A/F ratio. You can change those A/F ratios to anything you want.

To me, The safest way to start a new motor in with one of these EFI systems. They will only be as rich or lean as you want and if you don't change them, they are programmed to supply fuel and spark at optimum levels.

If I were you, I'd call Holley or FAST and talk to them. The Holley Techs have been great with me.

Bob

Bob-what you think of this??:

EBL_Flash

Gary

I don't profess to be an expert on EFI but I'll answer your question with a little history. My 54 Studebaker has an 89 TPI 350 vette setup which I installed by modifying a couple of OEM wiring harnesses and having the Chip re-burnt to eliminate EGR and VAT. I also had the vette ARAP code burnt in also. It runs and starts fine but I don't have enough miles on it to really access it. My attention the last two years is my 355 SBC Avanti which I built to rekindle my muscle car Jones. It has all the speed goodies and my original plan was to use an Edlebrock Thunder Carb which I installed. Could never get everything just right although it would run like a scalded ape.

Decided to convert to a Holley EFI Commander 950 TBI setup to allow more flexibility with it's programmability. Got a great price from a friend and installed it. The standard programs ran about like the carb, well but not perfect. The programming was just more than I found I could deal with.

Decided to make life easy and sold the Commander setup and switched to the Holley HP EFI setup. Put it in and it started and ran better than all above out of the box. It continued to learn and when I downloaded the results of the computer programming itself, I was surprised how far the timing and advance were from what I thought would work.

As far as the system you asked about, it looks like an less expensive Commander 950 setup from a GM box.

My opinion, You are probably just as far ahead to have a chip burnt with a decent GM code to fit your motor.

But for my money from my experience, I'll take the self learning Holley/FAST setup with the wide band O2 setup. This is the technology all of the newer cars use to control engine parameters and represents state-of-the-art and the safeist technology.

Sorry to run on but I hope this helps to explain why I continue to support the newest technology to minimize the issues you are worried about.

Bob

Thanks Bob for the detailed post.It is what I have been searching for in answers.I'll call Holley and let you know what they said.

very cool Bob.