Jump to content
TEAM SHELBY FORUM

Camshafts help!


devman85

Recommended Posts

Hi I have just had the comp cams XE254BH installed in my 2010 GT500 here in the UK, these cams said they needing no computer mods....

 

At low rpm everything is ok however at around 2500+rpm there is a very loud crackling noise coming from the engine and im very reluctant to rev it past that. I can hear the air intake is taking in huge ammounts of air far more than it was before.

 

My mechanic is insisting that the problem is that it is not getting enough fuel to ignite with the extra air, I've talked to comp cams and they say that they do not need tuning at all

 

Has anybody had anything similar or any suggestion I could try?

 

thanks in advance

 

Sukh

Link to comment
Share on other sites

Hi I have just had the comp cams XE254BH installed in my 2010 GT500 here in the UK, these cams said they needing no computer mods....

 

At low rpm everything is ok however at around 2500+rpm there is a very loud crackling noise coming from the engine and im very reluctant to rev it past that. I can hear the air intake is taking in huge ammounts of air far more than it was before.

 

My mechanic is insisting that the problem is that it is not getting enough fuel to ignite with the extra air, I've talked to comp cams and they say that they do not need tuning at all

 

Has anybody had anything similar or any suggestion I could try?

 

thanks in advance

 

Sukh

 

 

 

Are you sure the cam timing is correct?

 

I degree ANY cam/s I install, regardless of who makes it, just to insure it's timed right.

 

With 4 cams, it would be VERY easy to get one or two out of time.

 

Did your installer stick a degree wheel on the engine and measuer cam timing?

 

 

Phill

Link to comment
Share on other sites

I see that Comp says no tuning is required. Odd that ModMax says you do.

 

http://www.compcams.com/Company/CC/cam-specs/Details.aspx?csid=955&sb=2

http://www.modmaxracing.com/product_p/com106060.htm

 

If I was you, I'd contact Justin Starkey of VMP. A nationally recognized tuner here in the US, he swapped in a set of Comp's cams into his own GT500 (his are slightly more radical than yours). He should be able to offer you some good advice on whether tuning is necessary or not. My gut feeling is that you should consider a tune to optimize your new combination. Here's a link to his install...

 

http://www.musclemustangfastfords.com/tech/mmfp_1012_2007_shelby_gt500_comp_cams_install/viewall.html

 

Tob

Link to comment
Share on other sites

Are you sure the cam timing is correct?

 

I degree ANY cam/s I install, regardless of who makes it, just to insure it's timed right.

 

With 4 cams, it would be VERY easy to get one or two out of time.

 

Did your installer stick a degree wheel on the engine and measuer cam timing?

 

 

Phill

 

 

Phil I can only go by what the installation guy said, he is saying the timing cannot be wrong.

To be fair there is no problem at all when the car is not in gear it revs freely all the way to the redline it is only when in gear.....

Link to comment
Share on other sites

I see that Comp says no tuning is required. Odd that ModMax says you do.

 

http://www.compcams....x?csid=955&sb=2

http://www.modmaxrac...p/com106060.htm

 

If I was you, I'd contact Justin Starkey of VMP. A nationally recognized tuner here in the US, he swapped in a set of Comp's cams into his own GT500 (his are slightly more radical than yours). He should be able to offer you some good advice on whether tuning is necessary or not. My gut feeling is that you should consider a tune to optimize your new combination. Here's a link to his install...

 

http://www.musclemus...ll/viewall.html

 

Tob

 

 

Tob yes i was very confused when I bought the cams, I was going to go down the same route as you are saying however the entire reason I got these cams is they do not need any tune. I have talked to comp cams and they say timing but im not convinced tbh.

I can only go with a handheld tuner custom tune and datalogging as i live in the UK and these cars are very rare here so no real options of dyno tunes im afraid.

Link to comment
Share on other sites

Like I said, contact Justin at VMP. If not just to inquire about the issue you are currently having but to pick his brain regarding an optimal solution. If you can datalog you are ready to go.

Link to comment
Share on other sites

Like I said, contact Justin at VMP. If not just to inquire about the issue you are currently having but to pick his brain regarding an optimal solution. If you can datalog you are ready to go.

 

 

Right I got somewhere yesterday, I havent got hold of Justin yet as nobody was answering I will try again today.

 

I started the car yesterday and the engine management light was on all the time and there was no engine temp reading on the dial at all even after a 30min drive.

 

Anyway I had someone who is familiar with mustangs have a look at the problem and he was getting alot of error codes like engine coolant temp not readable etc.

At first he was convinced they had left of the knock sensor plug but after a while we had some advice from JDM to replace the stock spark plugs with NGK-TR6 which are 1 heat unit colder than stock and adjust these to 30thousandths of an inch and then get a tune as this is required.

 

Sparks are on order now but we decided to adjust the stock sparks and the engine is running much smoother.

Hopefuly with a tune the whole problem will be sorted.

 

Not sure about engine temp, the dial moves now and again and the rad fan is on constantly so we are suspecting a faulty thermostat currently.

 

Thanks for your help guys will keep you informed.

 

Sukh

Link to comment
Share on other sites

Not sure about engine temp, the dial moves now and again and the rad fan is on constantly so we are suspecting a faulty thermostat currently.

 

 

The T-stat won't keep the fans on all the time. The engine is cold from the start so the condition of the T-stat has no influence on the cooling fans at that time. Something is telling the fans to stay on;

 

It sounds more like a bad ECT Sensor or circuit. A ECT Sensor is *considerably* easier to change than a T-stat so if you want to use the shotgun approach, I'd start there (Logic & Ease of Access, 2 of the 3 parameters for a logical diagnosis- 3rd being History).

 

 

Phill

Link to comment
Share on other sites

The T-stat won't keep the fans on all the time. The engine is cold from the start so the condition of the T-stat has no influence on the cooling fans at that time. Something is telling the fans to stay on;

 

It sounds more like a bad ECT Sensor or circuit. A ECT Sensor is *considerably* easier to change than a T-stat so if you want to use the shotgun approach, I'd start there (Logic & Ease of Access, 2 of the 3 parameters for a logical diagnosis- 3rd being History).

 

 

Phill

 

 

Hmm I came across this thread http://www.teamshelby.com/forums/index.php?/topic/30767-trouble-after-evo-stage-ii-install/

same exact symptoms, defo a good place to start.

It appears comp cams are recomending the wrong springs for the GT500, Justin at VMP says the intake and exhaust springs should be different and not the same as Comp say!

Link to comment
Share on other sites

The T-stat won't keep the fans on all the time. The engine is cold from the start so the condition of the T-stat has no influence on the cooling fans at that time. Something is telling the fans to stay on;

 

It sounds more like a bad ECT Sensor or circuit. A ECT Sensor is *considerably* easier to change than a T-stat so if you want to use the shotgun approach, I'd start there (Logic & Ease of Access, 2 of the 3 parameters for a logical diagnosis- 3rd being History).

 

 

Phill

 

 

The ECT resitance values are ok between 60K ohms and 3K ohms so it doesnt look like it is that.

There is 12Volts going into it so im abit confused....

Link to comment
Share on other sites

The ECT resitance values are ok between 60K ohms and 3K ohms so it doesnt look like it is that.

There is 12Volts going into it so im abit confused....

 

There is 12v going to it?

 

Are you sure you have the ECT sensor and not the coolant temp gauge sending unit? They may be one in the same or they may be two different items. I'm not familiar enough with this specific system to tell you with certainty.

 

But unless something has changed, Ford EEC PCU's work off of a 5v reference signal, not 12v.

 

Do you have a wiring schematic avaialbe to see if the wire colors corolate with the voltage levels you're seeing?

 

Does the item you're testing have 2 wires or 3 wires running to/from it? I think there's a wiring diagram on-line, I'll look and if there is one, I'll check it and see if I can make sense out of the information you're providing me. Because right now, you've got me scratchin' my head!

 

 

EDIT: What year car is this on? And I'm assuming it's a GT500?

 

Phill

Link to comment
Share on other sites

There is 12v going to it?

 

Are you sure you have the ECT sensor and not the coolant temp gauge sending unit? They may be one in the same or they may be two different items. I'm not familiar enough with this specific system to tell you with certainty.

 

But unless something has changed, Ford EEC PCU's work off of a 5v reference signal, not 12v.

 

Do you have a wiring schematic avaialbe to see if the wire colors corolate with the voltage levels you're seeing?

 

Does the item you're testing have 2 wires or 3 wires running to/from it? I think there's a wiring diagram on-line, I'll look and if there is one, I'll check it and see if I can make sense out of the information you're providing me. Because right now, you've got me scratchin' my head!

 

 

EDIT: What year car is this on? And I'm assuming it's a GT500?

 

Phill

 

 

Phill it's deffo a ECT sensor as I was looking at replacements online. Does the GT500 have both? as I know late 90's GT's did?

 

Right with the engine running ie with the alternator going it has 12.2V going into the ECT not 5V. There are 2 wires 1 orange and 1 green although I'am colour blind haha.

 

A wiring diagram is exactly what I was trying to find online but im getting nowehere so far.

 

Yes it is a 2010 GT500 coupe.

 

Cheers

Link to comment
Share on other sites

Archived

This topic is now archived and is closed to further replies.

×
×
  • Create New...
...