What are the limits to the stock maf? I have read over on the thirdgen board that it is restrictive and just switch to speed density if you want performance. I'm new to the TPI realm so any help would be greatly appriciated. Reason I ask is bcuz I'm thinking of getting a 3rd gen formula and put a 400 with a 5 or 6sp behind it, but don't what to get into it and find out that I can't do what I want to do. I know that with sd you are limited to cam size and therefor how much power you can make.

Thanks,
Jeremy

 

If you are going for a lot of power, you could get a modified one. I'd rather not go with the SD setup which I have. It is less adaptive than the MAF. LPE sells descreened units with the heat sink ported out.

 

You can make good power with an MAF system but it is much harder to do so. The MAF presents a restriction in stock trim and always creates issues with making a nice cold air intake system. It is also prone to failure and is expensive to replace.

SD on the other hand is much easier to tune with regards to the PROM code and is actually much more flexible for adapting to radical combinations. If you plan on big mods, go SD and you will be much happier. Been there, swapped MAF to SD .

 

Yes, I would gut the Maf Sensor to improve flow. Just remove both screens and all internals and the flow will be more then you need.

 

The MAF system is limited to 255gps of airflow. What this means is you could have more cubic inches or a blower that demands more airflow, but the MAF will only recognize a max of 255 grams per second. So at that point you may risk severe engine damage if you run lean due to the ECm not richening the mixture to keep a stable A/F ratio.

 

Is there anyway around the limits on the stock MAF? Is the LPE one fix to be able to read more air or anyone else make a modified unit? Is sd the only way to go for performace on this motor and how big of a cam can you go with sd?

 

No, there is no way around the 255g/sec limit of the MAF system. No the LPE descreened MAF is not a "fix" and in fact creates more problems for those that know about PROM tuning.

If you want to go real big on a 3rd gen, get a SD car or just say screw it and get a GEN 7 DFI or somthing and be done with it.

 

Anyone know how big of a cam you can with sd before the vacum becomes so low that the car won't run or runs horrible? Reason I ask is bcuz my friend has a sd 5.0 stang and he can't run more than 220 @ .050 before the computer falls on its face from too low vacum. Has anyone had success with large cams with sd?

 

Acually, if you look at the PE % change to fuel vs. air ratio table, those are multiplication factors for calculating target air fuel ratio and that table is based on RPM (been a while, but I think it reads to 6400 RPM). If the rest of your calibration is correct (ie, like how the stock code is set for the stock L98), the ECM will command the desired air fuel ratio regardless of the MAF reading. The 255 g/sec is a limitation, but only in resolution. But a wild combo will cause far different flow characteristics compared to the stock L98 and will skew the ECMs assumed correct info from the MAF....

Now I am by no means endorsing using the MAF system on a wild combo.... Bad idea. Been there (sort of), done that. Just want to get the story straight-er . It can and has been done though. SD is maybe a bit more flexible and a bit easier to tune - IMO.

Now the SD system will use the VE table factors with that same PE % change to fuel vs air ratio table to set the commanded air fuel ratio. The difference is the MAP reads vacuum of various amounts right up to 1 ATM. So you basically can't run out of resolution without a forced induction system with the 730 ECM.

HTH