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Manifold about to MELT!

gatty

By gatty,
in Engines & Forced Induction

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gatty Mentor

gatty

Posted
Posted

hey guys

Turbo on rb25det shit itself so bought a aftermarket bolt on job (nothing too crazy just a tiny bit bigger). It's running stock boost, FMIC, POD and full 3" system.

Take it for a drive and it runs fine, boosts fine and seems to be ok, but after a short drive (<10KM) and no flogging got home looked under bonnet of mates car and the manifold was glowing red hot - took ages to cool off too - looked like it was about to melt!

Rang up some guy who said "it's running very lean don't drive it"

it's still running stock ECU - running lean would cause this? He was going to buy a SAFC - would this fix the problem????

thanks for replies

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siksII Grand Master

siksII

Posted
Posted

it can become red hot with the standard turbo, but usually only with a flogging of if it has a crap exhaust, if u left the heat sheild off maybe its just that u never saw it glowing before. but yes best to check a/f ratios as leaning out will make it hotter and brighter :rant:

gatty Mentor

gatty

Posted
  • Author
Posted

well no dyno around here - nearest would be 300km's - well there is one but it's very dodgey and useless operators...still a 30 min drive!

he was told that he needs a new fuel pump but i reckon thats a load of shit....igf the air/fuel is low the SAFC can fully control this correct?

siksII Grand Master

siksII

Posted
Posted

yes it can u can do that

but keep in mind r33 fuel pumps power limit is around 200rwkw(which your friends car would probably be close to)so if it is around that maybe its time to change it, they are not expensive anyway and a few people have had them fail causing the engine to lean out and die.

otto Collaborator

otto

Posted
Posted

i dont think the ecu would let the car run lean or make enough power for the pump to run out of flow. it will hit fuel cut before that happens. i dont think a safc is the solution if it is running lean either. I recon your car is fine my manifold glows red hot all the time you will notice it more at night

gatty Mentor

gatty

Posted
  • Author
Posted

well here's a few other things

1. it has a fuel cut defender installed

2. i think he as had the crank angle sensor off - placed it back exactly where it was when it came off though (apparently)

checked all water lines (cracked seal a bit) and they are fine

in regards to it being normal - it's is glowing like a molten bit of steel - litterally looks like it's about to melt!

Upgrading fuel pump, a SAFC would still be necessary wouldn't it to control everyhting?

Baz Experienced

Baz

Posted
Posted
well here's a few other things

1. it has a fuel cut defender installed

2. i think he as had the crank angle sensor off - placed it back exactly where it was when it came off though (apparently)

checked all water lines (cracked seal a bit) and they are fine

in regards to it being normal - it's is glowing like a molten bit of steel - litterally looks like it's about to melt!

Upgrading fuel pump, a SAFC would still be necessary wouldn't it to control everyhting?

Errr.. in regards to #2 I think you should double check to see if it is up the right way. As DNB said, retarded ignition can cause the heating of the manifold

Shaun Mentor

Shaun

Posted
Posted

What about an inlet manifold leak? This would make it run lean. I seem to remember a mates rotary whos inlet manifold glowed red hot due to this problem. Dunno the ins and outs of it though. Check your plugs; if its lean enough to cause this problem, the plugs will show it.

R31Nismoid Grand Master

R31Nismoid

Posted
Posted

that many stock manifold/turbo cars i have seen glow its crazy.

remember the stocm manifolds arent of $$$ materials.

XR6 turbos do it, my old coupe did it... my current doesnt anywhere near as much as its thicker metal etc

NZM.031 Grand Master

NZM.031

Posted
Posted

shaun, if the car had an intake leak, it would run rich as buggery. the afm would detect the air coming in, put in the fuel required for that amount of air, then the air disappears...leaving you with fuel, will run badly.

an a/m turbo will indeed change the a/f ratios, if its putting in too much air and the std components cant handle it, thats why the turbo is usually done last, too many ppl buy a turbo and put it on and drive away....then they are up for a full rebuild, when all they needed was a fuel pump, injectors and an ecu.

a safc will fix it up no probs, if tuning is too difficult, get an apexi pen type turbo timer, it shows a/f ratios....dont live by this reading as it can be fairly rough, but it will tell you whether you are way out. you can then tune the safc to what the turbo timer says...if the readings are between 12-14 under boost, the car should be fine, over 14.7 is running lean.

just a note, the car at times will run lean, such as on idle, and when you back off the accelerator, its supposed to do this, when you get a a/f gauge, it makes you worry when you see it the lean side off the clock.

cheers

Linton

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