I just did a '14 vette in speed density. The maf was awfully turbulent with the A&A kit we installed. Car turned out perfect but cruise control doesn't work until you enable the MAF back. Do you guys have any ideas?
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I just did a '14 vette in speed density. The maf was awfully turbulent with the A&A kit we installed. Car turned out perfect but cruise control doesn't work until you enable the MAF back. Do you guys have any ideas?
Might need a patch.
Funny you mention the turbulence. I had the same thoughts on the A&A car I did. The ECS kit doesn't have an issue.
Dave I think it's the fact that one uses a 4" tube and the other a 3.5" tube
Is the MAF on the A&A coming right off some bend? But anyways a 4" at idle/slow speeds doesnt make for very good resolution.
I am sure that's exactly what it is. There's no need for 4" piping on that stuff. Oh well.Quote:
Originally Posted by Ben Charles
The last one I did had to be left in SD as well. I'm not certain about the cruise control not working though...
He was thinking of replacing the pipe with a smaller diameter to help resolution. He even went as far to install a saxonpc screen in the pipe before the MAF sensor to help but it didn't.
I just ordered a TI blower kit from Andy and I asked to get a 3.5" tube along with the 4" tube (going to do some testing)
When I talked to Andy he was worried about "scaling" the tune, but since the maf hz ONLY is affected the tq tables shouldnt change due to just the maf table being scaled back from a tube size change
The C7 ECM is very flexible. There's no "scaling" issues.
Dave I agree 100%
Quote:
Originally Posted by DSteck
I hope Hptuners can come back with a patch or fix. It does pretty damn good in MAF but it does better in SD and I'm sure this will not bet the last Gen 5 tuned in SD.
The A&A kit we got had a screen in it. Beautiful kit. It was in a nice straight piece of pipe too. I think it is just going to be the nature of the beast on these.
Alvin, did you use an lt4 map sensor? You using 2.25s new VE calculator or bluecats tool?
You use the LS9 map on LT1s.
interesting, ive had the chance to log a few Whipple supercharged trucks with the whipple 4.0 inch CAI and they had perfectly smooth MAF readings, including my truck which has a Volant CAI (3.5" im guessing) before the Whipple. I wonder if the MAF prefers the high volume of air in a PD blower setup vs pressurized air in a blowthrough turbo or centrifugal setup.Quote:
Originally Posted by Alvin
The stock MAF location is 4" so that's why I designed my system around it. I think it isn't the fact that it's 4" that causes the turbulence but rather that the tube changes from 3" to 4" before the MAF. I think there is a change in pressure as the air expands to the larger tube that causes the turbulence.
Our LS7 kit uses a 4" tube but only transitions from 3 1/2" as it exits the intercooler. Because there isn't such a large transition there isn't the same issue. I just can't squeeze a 3 1/2" tube down the side of the radiator on the C7.
The screen before the MAF helps a lot. Making sure the timing tables are really smooth in the cruise area also helps. If the timing jumps from one cell to an adjacent one that's 5* different it makes the car buck slightly. With the screen in place and the timing smoothed out it really is hardly noticeable.
If you go to a smaller tube, the MAF has to be scaled way back just to get the car to run without being pig rich. I had wanted to avoid that.
Procharger uses a 3" tube and I can tell you that it makes the transmission shift weird. I just swapped one out for one of our kits and the trans (among other things) is a lot better. The customer loved it.
I'd hate to have to go to a smaller MAF tube but I'm looking at all my options.
Ben is helping me with an experiment or two.
If anyone has any helpful input, I'm open to it.
Use a smaller tube. I've never had issues with A&A kits on C6s, but the C7 was horrible, and it had the screen too.
Tube size won't impact the transmission. That's a matter of calibrating the MAF correctly. The ECS kit with the 3.5" tube was only slightly off from stock on the MAF. The A&A MAF table was way off from stock.
Procharger stuff probably shifts weird because their canned tunes are pretty bad.