Potential gains with these mods, SD to MAF?

[281pony]

sorry i know these type of questions get asked quite abit.

i have a cobra intake (stock), 70mm tb, 80mm maf, 1.7rr, full exhaust (bbk 1 5/8 el headers, offroad h /w no cats, flowmaster 2 chambers), K&N, and 3:55's.

going from a badly tuned sd car to a good running mass air car, what kind of gains could i expect? just kind of wondering what to expect, my car has no power right now.

aside from mass air, im getting new plugs, new wires, new coil, timing, ect to make sure its all fine.

thanks

 

[giddyup306]

You usually lose about 3 hp going from SD to MAF however it opens a whole world of opportunities for you such as adding an agressive cam.

 

[281pony]

even with the bolt-ons i have?

plans are in the very near future for heads and a cam, not expecting this to do anything amazing.

my car right now though is very low on power it feels like, off and on. its never run "right" since i got it. alot of things weren't set right, slowly been fixing/finding everything, and i was hoping the mass air set some of it straight. either way, with the heads/cam on the way mass air cant be a bad move.

thanks

 

[giddyup306]

Don't take that the wrong way it's defintately a good move. Better drivability and possiblly some better fuel mileage.

 

[281pony]

i didnt take it the wrong way i just figured going from a badly tuned car to a good running mass air car thats calibrated for the mods would gain some extra hp obviously, just how much? its a dog in first and second gear but seems to pick up in third.

hoping between the maf conversion, new plug wires, new plugs, new cap/rotor, coil, and checking timing ill feel a nice difference. if not, i KNOW it will be there with heads and a cam.

 

[Daggar]

I would imagine that if the car is tuned as badly as you say it is then you would stand to gain more HP by the switch. I'm not jsut talking about an over gain in HP power though. I'm talking about the gain in HP you will get across the entire power band. THAT... could make quite a difference.

 

[281pony]

yeah, its THAT bad.

kind of varies with the weather which is why i believe its partially to do with the sd not making the changes mass air will to compensate.

put it this way, from a dead stop first gear floored wont spin the tires. it takes about 5 seconds or so to wind out FIRST with all those mods, 3:55's and a 5-speed. second gear revs about the same pace, and third revs the same as first/second.

hoping mass air will help it out, or simplify those issues. time will tell i guess. did a compression check recently, all cylinders are at 125 which i thought seems low?

cousin has seen black smoke when i get on it though, and its not burning any oil. so im thinking its fuel related partially.

 

[giddyup306]

My suggestion to you is to fix whatever problem it is you have before you go modifying things. It will make life a lot easier for you. Plus if something goes wrong with your install you will then have at least 2 problems to diagnose which can be a hell of a headache. Take advice from someone that has been there

 

[Daggar]

My suggestion to you is to fix whatever problem it is you have before you go modifying things. It will make life a lot easier for you. Plus if something goes wrong with your install you will then have at least 2 problems to diagnose which can be a hell of a headache. Take advice from someone that has been there

I agree with Gidyup. If it seems like the computer is taking a long time to 'catch up' there are a few things I'd look into before resorting to a swap that may or may not fix your problem. Vacuum leaks would be first followed by ensuring that there are no leaks between your air filter and the throttle body (I know that doesn't make much sense but a hole in the tube once caused me quite a headache). Then I'd swap out the TPS and see if that made any difference at all (they're cheap). Then the vac hose that goes from the intake to the MAP sensor (weather it looks like it needs it or not). Then replace the MAP sensor itself (also check the vac tree to see if it's gunked up). If none of that works I'd start looking at the fuel presssure regulator and injectors. Have I forgotten anything anyone?

 

[281pony]

mainly mass air is to help simplify tuning somewhat and for when i do my heads/cam.

i have brand new injectors (1-2k miles?), no airleaks, checked over all the little stuff. they are bosch 4-way injectors, 19#, maybe they could be part of the problem with too much fuel?

i have an afpr, its at 35 with no vac. tried adjustments, nothing seems to help much if any.

it doesnt have that "instant" throttle my cousins mustang had with mass air. you go and punch it and it takes a second to respond. almost seems like its a carb'd car. sometimes it responds better at night, snappier throttle, smoother shifts, faster rev's, ect. my cousin seemed to think it was sd related from that, with it not making the adjustments to the air changes.

 

[Daggar]

mainly mass air is to help simplify tuning somewhat and for when i do my heads/cam.

i have brand new injectors (1-2k miles?), no airleaks, checked over all the little stuff. they are bosch 4-way injectors, 19#, maybe they could be part of the problem with too much fuel?

i have an afpr, its at 35 with no vac. tried adjustments, nothing seems to help much if any.

it doesnt have that "instant" throttle my cousins mustang had with mass air. you go and punch it and it takes a second to respond. almost seems like its a carb'd car. sometimes it responds better at night, snappier throttle, smoother shifts, faster rev's, ect. my cousin seemed to think it was sd related from that, with it not making the adjustments to the air changes.

What you describe sounds either like a vac obstruction going to the MAP sensor or a bad MAP sensor. Either way it seems like the MAP sensor is not getting what it needs to throttle up. Your 19lb injectors are not too big btw, that's the stock size.

 

[281pony]

yes, i know they are stock. was just wondering if the 4-way spray pattern might be giving more fuel then the stock ones and causing it to run rich.

im 17, not that knowledgeable yet, but the map is gone when i go to mass air isint it? ill go check the map hose to make sure, but nothing really indicates an airleak or obstruction.

although, when i first start the car up in the garage, i can hear a hissing almost sound. its in the corner of the garage right up against the wall though and its only upon first start-up. after it idles down it goes away, an airleak wouldnt just be off and on like that

thanks for the advice, ill run out and check the map.

 

[Daggar]

yes, i know they are stock. was just wondering if the 4-way spray pattern might be giving more fuel then the stock ones and causing it to run rich.

im 17, not that knowledgeable yet, but the map is gone when i go to mass air isint it? ill go check the map hose to make sure, but nothing really indicates an airleak or obstruction.

although, when i first start the car up in the garage, i can hear a hissing almost sound. its in the corner of the garage right up against the wall though and its only upon first start-up. after it idles down it goes away, an airleak wouldnt just be off and on like that

thanks for the advice, ill run out and check the map.

If you're hell bent (and it sounds like you are) switching to MAF then by all means do it. It's not a bad move at all to go ahead and be done with it. As far as your MAP sensor going away, that will depend on the conversion you do. Most SD to MAF conversions retain the MAP sensor though it's not really used. The electric plug stays connected but the Vac line gets capped off.

Now onto your hissing noise. Do you hear that only when you step on the gas? If so, pop the hood, remove the intake hose assy and manually operate the throttle. If that hissing noise is coming from the throttle body during rev up then your throttle position sensor is most likely bad (not opening the butterfly to allow enough air for the throttle up).

 

[DMAN302]

A poor tuned SD car will be a poor tuned Mass air car. You need to save the cash and put it toward a full tune -plugs wires cap rotor fuel filter (probably old as you are) set the timing at 12Deg (SD likes 10-12DEg on avg) and check to see if the clutch is slipping. SD is not as evil as many make it out to be it adapts well and often is quicker than mass air cars in mild mod form. Pull the codes and see if you have any key sensors out, and check again and again for vac leaks...SD runs heavily off vac for info leaks can cause havoc. As for MAP sensor it stays even after conversion. Mass is great I like it lots but only converted cause my new combo was bit on the high side of what I felt SD could handle plus I was upgrading my injectors and MAF and I knew SD would not like that but at near 300RWHP more fuel is needed. Guess what I'm saying is don't look for easy way to get past the maintenence that needs to be done cause there is no reason your SD car can't run like a raped ape just needs some TLC

 

[5.0fox]

when i went to mass air because of my cam it made my car run much smoother. i dont think its a bad choice to go to mass air but dont do it until u need it.

 

[DMAN302]

YUP great way to go when the car begins to reject the fuel air curve requirements on the engine due to mods..HOWEVER your car is running poor cause something is a miss..you likely will find yourself out several dollars with a conversion and a really good idle but the problems causing your power being down will STILL be causing you big problems. You have plenty of room to grow before you need to convert..save your cash and build up your foundation then look to build on that foundation.

 

[281pony]

"aside from mass air, im getting new plugs, new wires, new coil, timing, ect to make sure its all fine"

im doing a full tune-up also along with it. plugs are only 2k miles old, along with the cap/rotor as it is, but im just replacing it all fresh with the mass air. im not trying to avoid anything, i just said im hoping it aids in the tuning issues.

not to mention fuel filter is only about 2 months old as well.

onto the hissing sound. i checked my map line to the intake, the arm rotated somehow during the install of my cobra intake and the line has a kink in it. the mass air conversion requires you to plug that line though i believe, so tomorrow when my mass air conversion arrives ill plug it and go from there.

i looked over all of my lines, no holes, no air leaks. everything looks good. it only makes the sound at idle, it is idling up a bit on startup. about 1000 rpm. just going to see what mass air brings tomorrow when its finished, assuming it works havent had the best of luck so far.

 

[281pony]

ok updated a little.

today my mass air conversion came, i installed it. car runs pretty good, and it actually worked. my problem is still no power in first gear, i went out for some testing and my cousin said it seems like it doesnt want to rev and is running out of horsepower.

on the hose to the back of the intake, i felt back there today and it is kinked badly like a V. the little arm on the intake twisted somehow so its kinked now. does this sound like a good possibility to why im losing hp somewhere?

first gear winds slow, and doesn't have much torque at all, not enough to spin the tires from a stop still. let it wind, then go to second and its a different car from earlier today, pulls HARD, third pulls harder also, never went to fourth. so mass air helped out alot, but still not quite there

so basically, i'm not where i should be still in all gears we think. first gear is the big issue though.

this weekend i will be putting in new plugs, new wires, cap/rotor, timing is fine, injectors are new, maybe a new air filter since the one i got is kind of a pos. other then that, does that kinked hose sound like the problem?

fp was also adjusted to 38 psi, no vacuum.