ITBs

[bkaesvziank]

I currently have an 87 325is that I have run through pretty much from top to bottom over the last couple years that I've owned it. Everything is mechanically sound and I love it. I'm just getting the itch to do something fun with it now. I have done suspension, interior, exterior, and rebuilt the engine to oe spec. I want to get a little bit more power out of it so I'm planning on getting a bimmerheads head, long tube headers, a cat back, and obviously ITBs. The ITBs are where I'm running into a road block.

I've read up and am planning to go with ITB's from racehead. Now here's where the questions start. I'm unsure of what type of tuning I should use. Alpha-N or run a plenum with a maf? If anyone here has any experience I'd really appreciate the help.

[TurboJake]

It depends on if you want to stick to the motronic ECU or run a different ECU.

I personally have no experience running an ITB setup with a MAF and plenum, but there's no reason for me to believe why you couldn't do it, considering I'm running an Audi MAF on my car using motronic. I will say that I personally hate Alpha-N for a car that's driven on the street. It's silly to me because you lose any and all fuzzy logic and adaptive learning for the ECU. Being as I live in WI and MI with it's HUGE variations in outside temp, that is a very very big deal.

So, it boils down to "Do you want motronic, or are okay with going Megasquirt"?

It also should be noted, that ITB's don't really do much on M20's, but if you want to do it, go for it.

[bkaesvziank]

I planned on running ms. I have a little bit of experience with it but only running speed density. I have 0 experience running alpha-n. I figured it wouldn't be as good but I wasn't too sure.

Also, I know I probably won't see much of a gain. I've just always been infatuated with them. I was going between fi or itb and I figured since I've had turbo cars in the past, it's time to try something different.

I know many people see it as a waste of money and I know I'm not gonna see a good hp/$ but that's not really what I'm going for. I just want to try something different and have fun with it.

[digger]

id be interested to see what else would gain 25-30whp for the price....

[kbaszak]

Is that 25-30 with just itbs or with head work and other mods?

[digger]

itbs & tune on a 2.5, ITB only 2,8 and 3.1L give or take

[kbaszak]

Wow that's impressive. How much do you think they would make on a 2.5 if you did supporting mods? (head work, injectors, proper length headers, etc)

[bkaesvziank]

id be interested to see what else would gain 25-30whp for the price....

Yea, but most people will say that you can get more than double the horsepower with a turbo kit for ~4k where as you're only getting 25-30 with itb's and an ems for ~2-2.5k. At least that's what I've run into with people

[digger]

Yea, but most people will say that you can get more than double the horsepower with a turbo kit for ~4k where as you're only getting 25-30 with itb's and an ems for ~2-2.5k. At least that's what I've run into with people

let those people get a turbo if they want............

[bkaesvziank]

I agree. I'm guessing you have run, or currently run, itbs? If so, what's the fitment like and is there any room to make a plenum to get around the horns?

[digger]

I agree. I'm guessing you have run, or currently run, itbs? If so, what's the fitment like and is there any room to make a plenum to get around the horns?

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