Help Please Gt40

[pissedoff92]

Ford racing performance parts is not answering my emails to try and get a larger baffle for my junk chinese cobra intake. Anyways I found a full gt40 upper and lower for 75 bucks and I want it, but Ive heard that you can only use a 96 or early 97. this is off of a 97 explorer but how do I tell if its early late or what not. Also could someone explain what the difference is between years because I found like a 99 explorer locally that I might be able to buy the whole motor out of. Ive searched but its hard to use the right keywords to find what I need to know

 

[NIKwoaC]

Look in the commonly asked questions thread over in talk and go to the GT40 section. There is a thread on it. Too lazy to pull up the link for you haha.

 

[a91what]

as long as the intake has the provision for the egr your good. The IAT sensor boss will have to be drilled and tapped. you could just get the baffle and put it on your cobra intake they flow about the same numbers... i have a full explorer intake sitting in my shed i can see no real differance. you will need an egr plate for your TB on the explorer intake, its built in on the cobra. IF you get the Intake see if it comes with the TB and all they have a 65mm tb from the factory you can use it on a fox with some modification. The later Explorer motors 97 1/2 and up run the gt40p heads they are a good upgrade from stock e7's but you need to make sure your headers will fit, due to the new plug angle. I would get the entire motor pull it apart use the heads swap the larger baffle out into your cobra intake. Put new springs on the heads bigger cam..... ect. Those heads make great power.
Then you have an extra block if you **** something up.

 

[pissedoff92]

i was going to get gt40 heads but I decided against them only due to the monetary factory. you get a set of used heads, you want better springs a valve job so on and so forth, after all is said and done youve got 700 bones in a set of iron gt 40's you can get them new for that much and for 1000 bucks you can have trickflow twisted wedges which is what Ill be buying next. My car already has an unknown spec cam in it. So I plan on going with the whole trick flow top end kit. I personally hate the way the uppers look from trick flow but Im a less show more go kind of guy anyways. Really though the only reason I bought this intake (I did end up buying it) was for the lower. Im going to use the cobra upper that I have. If I use the explorer lower do I still have to drill and tap for the IAC or is that in the upper?

 

[Gearbanger 101]

i was going to get gt40 heads but I decided against them only due to the monetary factory. you get a set of used heads, you want better springs a valve job so on and so forth, after all is said and done youve got 700 bones in a set of iron gt 40's you can get them new for that much

Your cost estimates are way high IMO. GT40 heads can be had for $100-$200. A decent set of springs and a valve job is going to cost you another $300 or so on top of that. That's a fair ways off from $700.

I still think they're a great bang for the buck....just not as big of a bang as aluminum heads. Then again....with the bigger bang, comes the bigger price tag.

 

[a91what]

a few friends of mine have aluminum heads. and have had machine work done after overheating the engine.... just saying it happens. I pulled a engine out of a junkyard 96 explorer whole thing $300 smackers.... Maybe i got a sweet deal but i would never pay more than 150 for a set of gt iron anything... but after a valve job and springs $300 investment bang for your buck.. If you know what to do irons are very forgiving to a dremel ( just hit the exhaust) work over the roof take out the humps cut em wide on the sides and DONT touch the FLOOR!!!! take your time save your money. ( pretty easy if you use grinding stones, cutters remove to much material to fast)..
YES you will have to have a machine shop drill and tap the boss for the IAT sensor, it is in the #5 runner on the lower intake... you will see it clearly if you compare the two lowers. Some take and extend the two wires for the IAT and move it into the air box, if you run an CAI you could put it in the tube but you would still have to drill.. Then Epoxy or use a rubber compound to seal the sensor.
BTW the two lowers flow the same.... i would just swap the baffle

 

[ratio411]

Drill and tapping the IAT is easy cheezy. Don't let it scare you.
I think the only thing you have to really worry about is if you still have your EGR functioning, then you need to get the EGR equipped intake.
Just do away with your EGR and AIR systems, and you can use whatever one you like.

 

[NIKwoaC]

a few friends of mine have aluminum heads. and have had machine work done after overheating the engine.... just saying it happens. I pulled a engine out of a junkyard 96 explorer whole thing $300 smackers.... Maybe i got a sweet deal but i would never pay more than 150 for a set of gt iron anything... but after a valve job and springs $300 investment bang for your buck.. If you know what to do irons are very forgiving to a dremel ( just hit the exhaust) work over the roof take out the humps cut em wide on the sides and DONT touch the FLOOR!!!! take your time save your money. ( pretty easy if you use grinding stones, cutters remove to much material to fast)..
YES you will have to have a machine shop drill and tap the boss for the IAT sensor, it is in the #5 runner on the lower intake... you will see it clearly if you compare the two lowers. Some take and extend the two wires for the IAT and move it into the air box, if you run an CAI you could put it in the tube but you would still have to drill.. Then Epoxy or use a rubber compound to seal the sensor.
BTW the two lowers flow the same.... i would just swap the baffle

Ha, just because you have some friends that skimp on their cooling systems doesn't mean aluminum heads are in some way inferior to iron. Overheating can damage a lot of things.

 

[ratio411]

Done right, aluminum heads are superior to iron when it comes to cooling.
But yeah, the aluminum is more easily damaged if you don't do the cooling system right.

 

[pissedoff92]

I deleted the smog pump. but im keeping the EGR. the explorer intake I bought has provisions for internal egr so my EGR will still function as it was intended. If you get rid of the egr you run into issues anyway. Anyone know what size drill and tap for the IAT? And about the heads. I look at it like this. 500 bucks 700 bucks either way i dont really care to spend half of the cost of aluminum to just upgrade in a year. Why do things more than once?

 

[NIKwoaC]

500 bucks 700 bucks either way i dont really care to spend half of the cost of aluminum to just upgrade in a year. Why do things more than once?

Good strategy

 

[pissedoff92]

So im confused. Is the ACT and IAT the same thing? Would the easiest option for me be to lengthen the wires and plumb it into my intake pipe on my CAI? I already have a hole in the pipe where someone had a nitrous jet and its after the MAF and is not currently being used. would that work?

 

[NIKwoaC]

I've heard bits and pieces about how the cooler temps in the CAI mislead the computer into thinking the intake air is colder than it really is. I would run the IAT sensor in the intake port where it is supposed to be. And yes, IAT and ACT are the same thing.

 

[a91what]

If you are going to buy a new heads the best option is go big.... none of us are happy with fast very long.... soon it just wont have the same appeal it once did. I run irons becouse i get port work done very cheap, ( family hookup) and im on an extreme budget... BTW nik is right they did skimp on there cooling system's big time. that said dont.

 

[pissedoff92]

newer vehicles run the IAT in the actual intake tubing if the comp sensed a cooler reading wouldnt it run a little richer mixture I cant see that being a huge ordeal. im leaning towards the intake pipe for a few different reasons. one the hole is there already two I dont want to drill and tap my chinese cobra lower so I can then steal the baffle off of the 65 dollar explorer intake and then the explorer intake is useless again. but I also dont want to take the exploror lower to a machine shop to be professionally drilled and tapped

 

[Gearbanger 101]

I've heard bits and pieces about how the cooler temps in the CAI mislead the computer into thinking the intake air is colder than it really is. I would run the IAT sensor in the intake port where it is supposed to be. And yes, IAT and ACT are the same thing.

Most ACT temp sensors are actually located somewhere in the intake track....usually the air box. Locating them in the manifold itself actually can have a negative impact on power, as they become heat soaked and can cause the engine to pull timing. Safe, but detrimental to horsepower.

Only vehicles with forced induction benefit from having the ACT sensor in the lower manifold, as ACT's are not the same exiting the power adder as they were going in.

 

[NIKwoaC]

Most ACT temp sensors are actually located somewhere in the intake track....usually the air box. Locating them in the manifold itself actually can have a negative impact on power, as they become heat soaked and can cause the engine to pull timing. Safe, but detrimental to horsepower.

Only vehicles with forced induction benefit from having the ACT sensor in the lower manifold, as ACT's are not the same exiting the power adder as they were going in.

I understand that, but in this case the computer is calibrated to see the higher temperatures that an ACT sensor would see when mounted on the lower manifold, since that it where Ford installed them in the factory. Moving it out into the CAI is only going to fool the computer and potentially lead to problems- not performance benefits.

Since this has come up before, I decided to do a little research using the tweecer to check how the computer might react to lower than expected ACT temps/readings.

Here is my new writeup...

Hope it helps,
jason


How will the Fox computer react to the ACT being moved from the lower intake to the Intake Airbox?
Thumbing through the TwEECer (CalEdit) this is what can be seen...

In the X3Z Calibration
FN 825B - ACT will increase the engine idle rpm after about 192F, maxing out at 64rpm by 208F
FN 220 - EGR Multiplier is 0 until 58F, maxes out at 1 by 60F
FN 126 - Spark advance starts to retard at 160F maxing out at -2* by 190F
FN 135 - WOT spark advance is retarded starting at 150F, maxing out at -6* by 240F
FN 300 - Open Loop Fuel Multiplier is unaffected by ACT (always 1)
SCALAR - ACT MUST be between 100F and 200F for the Adaptive Strategy to start learning

In the A9L Calibration
FN 825B - ACT will increase the engine rpm by 48rpm at 200F, and a max of 72rpm at 226F
EGR Multiplier is .8 until 0F, then rises to a max of 1 by 56F
FN 126 - Spark advance starts to retard at 160F maxing out at -2* at 190F
FN 135 - WOT spark advance is retarded starting at 150F, maxing out at -6* by 240F
FN 300 - Open Loop Fuel Multiplier is .64 until -40F, .81 by 0F, and maxes out at 1 by 76F
SCALAR - ACT MUST be between 100F and 200F for the Adaptive Strategy to start learning

So what does this mean?
Idle speed – Obviously for both calibrations the affect is going to be minimal, assuming all other idle contributors are working properly. Moving the ACT to a cooler location should not have a major impact on idle speed.

EGR – Moving the ACT to a cooler location will affect the function of the EGR. It would not be recommended to try and pass an emissions test with the ACT in the airbox on a cold day (below 60F).

Spark – The Spark Advance is RETARDED with higher temps. Moving the ACT to the airbox can help to keep ignition timing higher. However, keep in mind that Ford used the ACT as a ‘Safety Factor’ for preventing high temp detonation. False information to the EEC-IV will make detonation more likely when the engine is warm/hot.

Fuel Multiplier – The Fuel Multiplier increases with higher ACT temps. Due to the low temps at which the ACT will impact the Fuel Multiplier this is not likely to cause an issue.

Adaptive Strategy – This may be the most critical one for most daily driver Mustangs. Not allowing the Adaptive Control to function (because the ACT never sees 100F in the airbox), could hurt fuel economy and could cause drivability issues.

 

[pissedoff92]

ok that being said. how do I put the larger baffle on my chinese cobra lower.