is it ok to run a 2.9 and 42lb injectors without any cooling mods ive seen a few people do it but i just want to try my hardest not to blow up my car because that would be bad

 

It's possible for sure, but I personally recommend 2.8 and 60lbers to all of my clients. Depending on where you are located and what tune you are running the 2.9 pulley can push the 42lbers to the point where they are static, but again it just depends on certain situations.

 

well if they go static then what happens

 

You will be starving the motor of fuel. Basically look at it like this. Once an injector is spraying 100% it can't spray anything more. So if your idc's aka (Injector duty cycles) are at 105% then you are not getting 5% of the fuel that your motor needs. I highly recommend thinking about going with a 2.8/60lber/custom tune setup. You will be much happier in the end and will have room to breath, aka upgrade.

 

if you're just going to want a 2.9 42's are safe with a custom tune that doesn't command a **** ton of fuel (gm1 & 2)

 

There are other things that play into it besides just the fuel, but you can get away with it on a custom tune, however it's still hard on the injectors. For the money, aka 160 bucks for 60s and a harness, I really don't think its worth the risk of a motor.

 

what do you mean other things that play into it? 42's are safe with a 2.9, I ran a 2.8 on gm2 for a week and my idc's were 102 at 6900 rpms. I do have 60's now, because I wanted room to work with but if the op wants a 2.9 and would like to stick with the 42s and use 60- money for a tune it's perfectly fine

 

to the OP, you should definitely get some cooling mods. at least a heat exchanger. they are not that hard to install and give you way more cooling for all the heat that 2.9 will be making. and 60s would be a better choice over the 42lb injectors because you wont be maxing them out / pushing them to the limits

 

There are a lot of things that play into it. It depends on how modified the vehicle is, how much air you are moving, what air to fuel ratio you are commanding, the elevation, temps, a lot of things decide whether or not it is "safe" to run 42s and a 2.9. Can people get away with it, absolutely, do I consider it "safe" not without a custom tune and seeing the idc's myself, no I don't.

 

ok, that's the reason I said a custom tune not commanding **** tons of fuel in my first post. All of the things you listed are directly related to fuel ( p.e. stft's ltft's)

 

I'm not arguing with you lol. All I am saying is that a custom tune is in order for 2.9 and 42lbers, and still then the idc's at times can be to high for my likings, also depends on how high your revving out to.

 

ok well im going trifecta does that help me

 

lol I know I'm just playing devils advocate to voice another opinion

and I do agree with getting 60s for more room to play in the future

no he likes to run people rich, get 60s or an hptune

 

I ran a 2.9 and 42s for 1 year with a custom tune no stg 2 tune bull crap and my idc was right at 85-90% some where there. It wasnt too bad can you do it sure you can. But if you ever want throw a smaller pulley on you should get bigger injectors right off the bat. I would go with 60s 2.9 pulley some cooling mods then start to drop pulley and see what you think. or just go with ottps stage 3 with the tvs 80s and a tune. You probly would like that better.

 

ive got 60's and a 2.8 for sale, i can sell you those, and a tune, and your golden

 

i got a 2.8 but i got no cooling mods

 

wideband?

 

You can run a 2.8 and 60s without cooling mods as long as you aren't hot lapping the car at the track or doing back to back to back to back pulls. I know a lot of people that have ran 2.6's on there cars for a long time without cooling mods. They heat up quicker, but for just the occasional 2nd to 3rd gear highway fun pull, you are fine.

 

nope no wideband im new to this stuff lol thats why im asking you guys

 

A wideband is a good idea to purchase if you are going to be modding the car. This allows you to know exactly what air to fuel ratio the vehicle is running. It's also very important for the tuners end of things so he can know if the car is dialed in or not.

 

also im talking about daily driving with some fun lol not like 5 hours at the track or anything like that

can a wideband run off a stock 02 sensor or what

 

A wideband is a must. I would get a wideband then start doing the modding like pulleys and injectors. Without a wideband a tuner can not tune your WOT well he kinda can but you are way more likely to screw your engine over. Like Zach said if you dont plane on alot of pulleys you can drop to a 2.7 and 60s and call it good. I do alot of racing so I will have like 3 pulls back to back. I have dual pass and heat exchanger and it keeps my car cool.

 

defantly... you can find aem's widebands usually pretty cheap.. i had one of those for sale too, but someone just bought it lol

 

i ran a 2.9 on gm s2 for a bit with no cooling mods and it worked fine! no cel's or anything but then again im at 4,500 ft elevation... now i got cooling mods and gm s3 + trifecta and it is hella faster than it used to be!

 

ok can the wideband use the stock o2 sensor bung and not freak out or is there a way of wireing it so the car will think the stock one is still there