granatelli MAF question

M

Mac-man

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Nov 7, 2003

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south texas

Nov 2, 2008

#1

• Nov 2, 2008

• #1

ok the 89 gt i just got has a granatelli MAF on it with 24 lb injectors. the only thing is the meter is based off of a lightning housing with the granatelli meter on it, and an adapter to plug the meter to the factory harness. what i am wandering is, if this is too big for an NA stang .... as i am having a few driveability issues with this car, and have never heard of a 90mm meter on a foxbody before...

 

vristang

15 Year Member

Mar 31, 2005

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Seattle

Nov 2, 2008

#2

• Nov 2, 2008

• #2

It may be a little over kill for what you are currently running (in your sig), but I wouldn't replace anything until you KNOW what is causing your idle problems...

codes?

 

M

Mac-man

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Nov 3, 2008

#3

• Nov 3, 2008

• #3

i am not getting any codes ... thats the whole thing that has me puzzled

 

vristang

15 Year Member

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Seattle

Nov 3, 2008

#4

• Nov 3, 2008

• #4

check for vac leaks?

 

B

blubullett

Member

Jun 22, 2006

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Modesto, CA

Nov 3, 2008

#5

• Nov 3, 2008

• #5

The problem is it is granetelli. I bought thier coil packs and they were garbage.

 

B

bandmc

New Member

Mar 20, 2007

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Nov 3, 2008

#6

• Nov 3, 2008

• #6

Yea, thats the problem. The brand name. Way to help out. Why do people constantly give stupid advice here?

 

8

86mustang84

New Member

Nov 4, 2008

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Nov 4, 2008

#7

• Nov 4, 2008

• #7

idle

Mac-man said:

ok the 89 gt i just got has a granatelli MAF on it with 24 lb injectors. the only thing is the meter is based off of a lightning housing with the granatelli meter on it, and an adapter to plug the meter to the factory harness. what i am wandering is, if this is too big for an NA stang .... as i am having a few driveability issues with this car, and have never heard of a 90mm meter on a foxbody before...

Click to expand...

hey,im using a 70 mm mass air,i just converted.i still get heavy surges that will even stall the car when it warms up its fine. it could also be where the mass airflow is mounted,try to get a good 12" straight before it.mine wouldnt run with it right off the manifold.it might be to big,im goin to be twin turboing mine and peaople have told me not to go over 75 cause the heads aint flowing that much more air.do u have upgraded heads,24lb injector may cause drivability beacause of the wayu the computer compensates at idle.what upgrades do u have that support the airflow for the use of 24"s?

 

M

Mac-man

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Nov 7, 2003

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south texas

Nov 4, 2008

#8

• Nov 4, 2008

• #8

the car has a full exhaust, a trick flow intake, and an frpp f-cam for mods. it has the 24 lb injectors, a 70mm throttle body and that MAF. it is also has a built bottom end although that has no affect on it needing 24lb injectors. i dont know why they are on here, it came with them. i was just curious if this MAF would be causing the surging idle.

i am going to be adding probably a set of world products windsor sr. heads pretty soon as i found a place with a good deal on a set of them. and to hopefully add to the need for the bump in injector size.

 

matador91

Active Member

Feb 1, 2007

107

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38

Bothell

Nov 4, 2008

#9

• Nov 4, 2008

• #9

I was having a surging Idle problem for a while, then I bought a new IAC module then adjusted my TPS and then no surging idle problems

 

NIKwoaC

中國製造

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Oct 31, 2006

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Chengdu Province

Nov 4, 2008

#10

• Nov 4, 2008

• #10

blubullett said:

The problem is it is granetelli. I bought thier coil packs and they were garbage.

Click to expand...

bandmc said:

Yea, thats the problem. The brand name. Way to help out. Why do people constantly give stupid advice here?

Click to expand...

I don't think he was out of line. Some brands are just known to produce flawed components. Take the advice with a grain of salt and move on. You shouldn't be abrasive with senior StangNet members anyway, the more friends you have, the better results you'll get when you need help.

Back to the OP...

Is your air filter exposed within the engine compartment? "Fanwash" can cause surging issues when your air filter is not properly shielded from your radiator fan. This is a big reason why most CAI kits put the air filter in the top of the inner fender- the air is pretty still in there. Also, any bends in the intake ducting immediately upstream of the MAF meter can cause it to have inconsistent readings.

90mm is really big for a 302, so maybe that could be your root issue. Most tuners like the MAF to be about the same size as the throttle body as a rule of thumb.

 

M

Mac-man

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Nov 7, 2003

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south texas

Nov 4, 2008

#11

• Nov 4, 2008

• #11

i have a brand new TPS set at .99, and a new IAC as well as a new coolant temp sensor, and basically all new sensors. the filter is an open elemtne filter basically where the original box was at, but i am using an electric fan that is hidden inside of the original fan shroud..... the only things i could even notice to be a possible problem, would be that the EGR has been deleted, as well as all three of the little solenoids/sensors that are behind the pass. side strut tower, and also the carbon canister and stuff .....

but as previously stated all sensors are new (i got them from the parts store i work at personally), and the timing is set at 14 degrees. i have also read that the MAF should be roughly the same size as the throttle body which is what led me to believe that maybe it could be causing the weird idle, since there really isnt any air velocity flowing through it at idle, being as it is so much bigger than the 70mm throttle body.

 

NIKwoaC

中國製造

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Oct 31, 2006

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Chengdu Province

Nov 4, 2008

#12

• Nov 4, 2008

• #12

Even with the E-fan, you can still have fan wash. Cut the power to the fan and drive the car. Does it still have issues?

Now that I think of it, what exactly are your "driveability" issues? Do you know for sure the meter is "matched" for the injectors?

 

M

Mac-man

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Nov 7, 2003

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south texas

Nov 4, 2008

#13

• Nov 4, 2008

• #13

the exact driveability issues are a bad idle when i first start it in the morning, and then some slight bucking of the car up until about 2200 rpms, when just cruising even when warm. when i open up the throttle it runs fine all the way through the powerband it is only when driving around.

i am under the assumption it is the right MAF for the 24's, based on the receipts i was given with the car, although that doesnt mean the wrong one was shipped. i have been contemplating just putting some stock 19 lb injectors in it with a stock MAF to see if maybe it helps to cure some of the issues.