i am very intersted in tuning, have read and unerstood some of the stickies, and i understand i have to buy all the crap before i can understand what the hell all those code names are

my problem starts at this, im going from 305 tpi to 350 tpi
obvisoly i want to mod my 350 before it goes in with cam and maybe a little compression bump,

where would i get started? can i take my 305 chip out and just load a 350 file on it? will i be able to even make the car run!??? im sooo scared of this tuning thing because i dont want to have a 5000 doller motor and 1000s invested in tunign stuff and not be albe to drive the dam car! should i just get a custom chip made to all my engine specs by an expert, then tune from there?

i cant belive there isnt a software where you just put in your specs, and it burns it for you,, it is absiluly bizzare that i have to adjust voltages and not see how it affects the car unless i have a dyno!!! im soo frustaded because i dreamed of a done up tpi for so long, and now realize that i have to be a software engineer to make a motor run!

should someone like me just buy a carb? i got a bad feeling this tuning thing will be the reason i dont get to drive my car this summer! if it doesnt run first time, im going carbed and making more power anyways!
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i also have speed density, another mistake. i thought it was better for tuning, apparently MAF will run with mods, and MAP will shoot rods through pans without a perfect 100 years of expeirence tuning

 

I wouldn't be too intimidated about tuning. Software like Tunercat makes it pretty straightforward for beginners IMO. And it doesn't require thousands of dollars to do. Just a couple hundred to get the Tunercat software, a chip burner and a chip eraser.

You should be able to erase your 305 chip and load a 350 cal onto it. What year is your car?

What I would do is burn (or obtain) a factory 350 TPI cal and run the car for a few days to let the computer "learn" where you're at with the new combo. Using a good scanner, you can see how far off the fuel is by the long term fuel trim (often referred to as Block Learn or BLM). For instance, the value that indicates fueling is right on the money is a value of 128. If you're significantly higher, it's running lean. If you're significantly lower, it's running rich. Getting the fuel curve right is the first step in familiarizing yourself with tuning. The spark timing also affects the fuel tirm as well, but like I said, start with adjusting fuel in small steps (and taking copious notes on what you do).

This is pretty general description. I think there's archived documents on specifics of exactly what I mean about "adjusting fuel".

 

awsome thanks alot,, so your bassically telling me,, thye scanner will tell me exactly what needs to be tuned,, and then its up to me to get it right!?

i know it aint easy, but as logn as i know my sir to fuel , timing, and whats going on it cant be to bad,

as long as it runs with a 350 chip and speed density (its a 91)
i just dont think it will work well with a cam and MAP because it runs off vaccum, and the cam will boost vaccum, thus creating a whole bunkload of codes throwing black stuff out my pipe

or maybe i worry to much... nothing wrong with loving your car to much

 

If you get a wild cam, it'll give you a lot of problems with a factory cal. However, a mild upgrade cam will be driveable with the factory cal. Just would need to tweak fuel and timing a little get it dialed in.

The scanner is probably your best friend in recalibrating.

 

zz4 cam sound to raunchy? 112 lobe seperation (im told this is max for computer controlled)

somwhere in the 220's dur and 500's lift im not sure exactly

 

ZZ4 cam is 208°/221° @.050. And yes, I agree that it's the largest cam you could run on a stock cal. But it's a damn good cam IMO. ZZ4's can make 350 hp on it with L98 heads and headers. With that cam it'll run decent with a stock cal, but you'd be leaving some performance on the table if you don't retune for it.

If you want to run something in the 220° range, then you are going to need some serious retuning. Timing and fuel will be way off.

 

k good, cuz zz4 has been in my mind this whole engine build,, 130 on ebay new!

im def goin with vortecs or good heads, and eventually hsr intake

thank you soo much for all this help, makes me feel alot more secure about building a motor with *****!!