I have a 86 mustang with a fresh 334 CID motor and 7576 Precision single turbo.
I'm running a FAST 2.0 system for the engine management.
The transmission is a Turbo-400 with 3.08 rear end gears.
When the car is on the dyno at a cruise in drive at 2500 rpm the headers start to turn red after about 5 minutes of run time. Fuel is 13.6. We've checked the timing on various cylinders and it all reads accurately with the timing tables. We've adjusted the injectors to really lean and really with no change other that the car starts to run rough once it's really rich or lean
The cooling system is massive and stays at about 170/180 degrees and then starts to creep up after the headers are glowing red.
We've smoked the engine for vacuum leaks and there are no leaks.
We've swapped out injectors with with no change as the cylinders still start to over heat with a load on the dyno.
The engine starts and runs fine with no missing and no smoke coming out of the exhaust.
There is no popping or coughing thru the intake or exhaust.

ANY SUGGESTIONS?

 

Whats the timing at cruise when glowing the pipes?

 

May have too little or too much timing.

 

Possibly either timing is too low, or something in the valve train is off. Pushrods too long if using stock style rockers, or rockers too tight if adjustable. I like high timing (40°+) at cruise when pulling good vacuum.

 

I've put together a dyno tuning checklist so I will put this on the list and check it and write it down.

 

OK. we have a mechanical roller lifter set-up so I will check the valve lash to see if it's ok. I'll check the timing at cruise and write it down.
Thanks for the feed back..

 

Sounds like simple low timing. Hope that's all it is.

 

I wish it was that simple .. we've retarded the timing and advanced it both ways until the engine starts missing and it still turns the headers red at a cruise with a out 2lbs of boost.

 

Does it have enough squish? Just in case it was de-compressed with low height flat top pistons. Lack of turbulence will cause slow burn.

Light throttle cruise can need as much as 60 deg of timing.

 

You're on a dyno when this occurs? Of course the headers are going to glow. No air flow around the pipes. Steel begins to visibly glow above 900 degrees and your engine EGT's are going to be between 1200-1800 degrees.

 

1200-1800 at cruise?

 

The temperature of combustion doesn't change, just the volume. I love watching the headers glow when I' m breaking in a cam at 2500 no load. A 7576 is not a real big turbo so at cruse you're already stacking air. You're in high gear and after 5 minutes you've reached the thermal saturation point. Watch a few glowing header vids. I wouldn't be worried about it in the least.

 

This

Shouldn't need much squish in a turbo application, loaded flow is almost always turbulent.

 

great videos...

 

Ok thanks we will check that...

 

Too bad about unloaded flow (cruise)?

 

I would think if you are loading the engine and you have low timing at 2psi of boost (12-20degrees) you are gonna have some glowing headers. Even just having boost at all is gonna cause back pressure and heat. I’m not really understanding what you are trying to achieve by loading the car at 2 psi and cruising because you will never see 2 psi at cruising and light throttle. Anytime you are in boost at all, your headers are gonna glow from what I can remember seeing.

 

Sure is... really terrible about the low load, low stress, high timing, low risk situations where quench wouldn't help if you had it.

 

No load, no boost.

 

Painful to listen to. Is the audio jacked,or just for me?