3 inch CAI ok to use for 351?

from6to8

There's suction so I used that end O_O
15 Year Member
Sep 2, 2012
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I'm thinking for what I'll build and use the car for that 3 inches should be fine. Car will not be on the track and not necessarily play around on the street too often; No daily either. BBK has a 3 inch black for the 86-93 for $69 and so wouldn't have to worry about getting it coated. The car is a 95

Stock 351 block ( 385 ish C.I.)
3.750 crank
AFR 185/195, Brodix 17 degree 195, or TF 11 R 190
Trick Flow R intake 75mm ( not box)
custom cam
75 mm accufab tb ( fox)
76-80 mm MAF
injectors (????) ....thinking 36's maybe?
1 3/4 LT's

Thoughts....?
 
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3" is slightly larger than the 75mm tb so I think its sufficient to not cause restriction.
What's the rule of thumb on the mass air meter as far as how much larger does it need to be than the throttle body? I was thinking 80 mm Pro-Am but I think I've seen where guys used for instance a 75 mm throttle body and then like a 76 77 meter
 
Just me and ignore this if you want but I'd save my money and use a stock airbox. Good quality and good airflow. Either way you need a meter calibrated for your exact intake tract. Many mo-smarter people than me on tuning can give you more info on that. Last thing you want is crappy idle syndrome.
 
Just me and ignore this if you want but I'd save my money and use a stock airbox. Good quality and good airflow. Either way you need a meter calibrated for your exact intake tract. Many mo-smarter people than me on tuning can give you more info on that. Last thing you want is crappy idle syndrome.
I don't even have the stock box and this is a 95 and it has a either a Mac or BBK pipe on it right now. I want to go away from the Chrome and use a black pipe so I could actually use I guess the one that's on there but I'll have to get it powder-coated so I probably just buy a new one. Actually the one that's on there is designed for the elbow and I'm going to get there I'm doing the fox throttle body conversion
 
I don't even have the stock box and this is a 95 and it has a either a Mac or BBK pipe on it right now. I want to go away from the Chrome and use a black pipe so I could actually use I guess the one that's on there but I'll have to get it powder-coated so I probably just buy a new one. Actually the one that's on there is designed for the elbow and I'm going to get there I'm doing the fox throttle body conversion
Evil trick. :D ...I thought you were working on an 86-93 from your post.
 
Having a larger diameter MAF is not really an issue but whatever MAF you have, fitting it to whatever piping you plan to use is important. As far as calibration goes, the MAF needs to calibrated for the size injectors being used. One thing to consider is that some MAF's are designed to work with a cone filter attached to them and others will need at least some length of pipe at the upstream connection.
 
Having a larger diameter MAF is not really an issue but whatever MAF you have, fitting it to whatever piping you plan to use is important. As far as calibration goes, the MAF needs to calibrated for the size injectors being used. One thing to consider is that some MAF's are designed to work with a cone filter attached to them and others will need at least some length of pipe at the upstream connection.
Gotcha yeah I know it has to be calibrated for the injectors. I'm going to use the exact same setup as well that come on the 94-95 to where the meter is down there before wear it's before the turn into the fender well. It's after the throttle body. I've seen some meters where the meter is right at the at the filter and therefore would have to be if you put it in the fender well Demeter would be inside of the fender well and I don't want it like that. I will call and check around with Pro-Am to see how about I know the tube is about 3 in I believe so I'll check with them to see about the diameter of the filter + 2 see if I need to get a reduced coupling or whatever
 
I hate speech to text.
but I live with it,
Yeah me too LOL it sucks but it's convenient. And the crazy thing is I just got this S9 earlier this year. I have an S6 prior to that for about three years and it worked way way way way better as far as speech to text. And yes with this phone I changed it from Samsung voice to Google Voice and all but it's still pretty stupid the way it messes you up a lot
 
I used a pro-m 80mm with a 3in intake pipe and 75mm Tb and it worked great. There have been numbers thrown around, like the maf should be at least 5% bigger than your throttle body. In reality as long as it’s the same size or bigger, it’ll work good.
 
I used a pro-m 80mm with a 3in intake pipe and 75mm Tb and it worked great. There have been numbers thrown around, like the maf should be at least 5% bigger than your throttle body. In reality as long as it’s the same size or bigger, it’ll work good.
Yeah I thought I remember reading that somewhere years and years ago reading where somebody or maybe a few people said it but I can't confirm exactly. So I don't know if that's a written Golden Rule that's a must or it's proven to necessarily do you work better than if you had both the same size so I don't know I guess I'll see