Engine B303 And E303...do They Need A Tune?

[TOOLOW91]

Thing is... At one time, I was also in the camp that believed that some store bought mass air meter was the ticket to supporting injectors large enough to power my new engine combo. Sure... I'd seen references to tuning and that sort of thing but a meter calibrated to run 42#. SWEET!

...and then I tried running it. LOL

So here I am... Brand new engine, Super charger sitting on top, 8 Green top injectors and SHINEY new mass air meter straight from PMAS that was SPECIFICALLY calibrated for 42# injectors and an A9L.

What could possibly go wrong????

Putting it into practice, that's what.

It wasn't until then that I began looking into and realizing just how much a difference there was between fuel injectors. I'd not idea that the EEC was responsible for the minimum injector pulse width and the minimum on a larger injector shot out a LOT more fuel than a 19 lb injector until it's been taught how low a slow a larger injector has to pulse in order to provide the same gas.

Those injectors just BELCHED fuel into the combustion chambers while being operated by by and EEC that thought it was half it's size.

THEN came injector slopes. WTF is this?!?! Why can't it just follow the same slope? Ohhhhhh.... because a 2% tweak on a 19 lb injectors is like a 20% tweak in pulse width on a 42??? :sigh:

But the list goes on... So I cart the thing down to dyno tuner that's several hours away and low and behold... SUCCESS! It was about a year later that I started looking to why things are the way that they are. I bought a wideband, started with an Anderson (reported to be the most user friendly) then looked into first duplicating the data on the custom chip I had burned then duplicating data coming from the PMS.

To those that can make a TwEECer do what it's supposed to do? My hats off to ya. I still can't make heads or tails out of the way that data is arranged in their software.

My buddy had (who I am assuming is xp8s buddy) - big daddy tune his turbo car with a pms and let me tell you that car cruised as nice at 140 as it did at 35 in traffic with 60 lb injectors in it


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[Noobz347]

My buddy had (who I am assuming is xp8s buddy) - big daddy tune his turbo car with a pms and let me tell you that car cruised as nice at 140 as it did at 35 in traffic with 60 lb injectors in it


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Yeah... One of the guys that I used to work with had some monster set of injectors in his track only (laugh) car. That thing ran very well on the street and had good manners. Particularly for not only the the injectors he was running but the cam he was running.

He ran some solid lifter monstrosity that I wouldn't even begin to guess about how to tune to make streetable in say.... a school zone.

Similar setup though... Anderson PMS.

 

[7991LXnSHO]

It looks like you are running some pretty extreme examples of injectors to justify your point. A basic letter camshaft with typical bolt ons will not need 42# injectors. I think you have missed the OP's needs and question.
Yes, a tune that gave superior street ability and mileage like the new ones would be awesome. Is it possible to get all that from a tune of the stock computer? Partially possible. Just remember how basic and slow the a9l really is. You could not run a new video game or Windows 8 on the chip. Is a tune needed to have a nice running car at this level? No, not at this level. Run a super charger and your 42# injectors and that is a different story.

 

[Noobz347]

It looks like you are running some pretty extreme examples of injectors to justify your point. A basic letter camshaft with typical bolt ons will not need 42# injectors. I think you have missed the OP's needs and question.
Yes, a tune that gave superior street ability and mileage like the new ones would be awesome. Is it possible to get all that from a tune of the stock computer? Partially possible. Just remember how basic and slow the a9l really is. You could not run a new video game or Windows 8 on the chip. Is a tune needed to have a nice running car at this level? No, not at this level. Run a super charger and your 42# injectors and that is a different story.

True story. We got off the OP's beaten path. Let's resume the initial conversation.

 

[f8tlfiveo]

I think the OP already had an answer before the 42lb injector talk, but as I said earlier. With his mods a tune is not necessary.

 

[larrym1961]

The only tuning I did with my E cam using an A9L computer and #24 injectors and #24 calibrated Pro M mass air meter was to set base idle @ 900 RPM. That was w/ IAC unplugged and spout connector pulled from distributor. The E cam seems to like that 900 base RPM idle.

 

[TOOLOW91]

It looks like you are running some pretty extreme examples of injectors to justify your point. A basic letter camshaft with typical bolt ons will not need 42# injectors. I think you have missed the OP's needs and question.
Yes, a tune that gave superior street ability and mileage like the new ones would be awesome. Is it possible to get all that from a tune of the stock computer? Partially possible. Just remember how basic and slow the a9l really is. You could not run a new video game or Windows 8 on the chip. Is a tune needed to have a nice running car at this level? No, not at this level. Run a super charger and your 42# injectors and that is a different story.

That is what I stated but xp8 swears there is no quality to be had with a tune as far as drivability and fuel trims


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