the7kid

specifics-ive searched the question and i havent really gotten a clear answer. i have an 87 tII swapped in to an 88 vert chassis. new streetport, rebuild by rotary ressurection not driven except for down the road a quarter mile once or twice. my mods are a 1 45degree bend intake, emissions completely removed, 3in cat-back exhaust, the one actuator door inside the exhaust manifold is off. the parts that i have replaced recently are stock fpr, stock fuel pump, 4 new stock fuel injectors, all vaccume hoses replaced. i am running the stock ecu also.
the question-is it normal to have a slightly red turbo from driving down the road a quarter mile and just letting it idle for 10min before? Is this a rich condition or a lean condition? Also, i have a hesitation right around the 2,500 mark. heavier throttle will make it stumble at 2,500 and then if you let off and ease into the throttle it wont stumble. this seems weird to me considering everything is stock on the car. could there ba a sensor that has gone bad or something like that. ANY HELP IS GOOD!

MidnightOwl

It isn't normal to have a glowing turbo after that small amount of driving. I'm not really sure what would cause it.

solareon

iTrader: (1)

glowing turbo is the sign of way too much advance on ignition timing or you are leaning out a crap ton. I would check your timing (read the fsm) and then see if that fixes your 2500 rpm stumble as well.

the7kid

im pretty sure the timing was dead on but i can retard it a bit and see if that helps

Aaron Cake

iTrader: (1)

I wish people would stop assuming that a glowing rotary turbo is because of a lean condition, because IT IS NOT. You're either too rich, or not enough timing.

Make sure the CAS is stabbed correctly.

the7kid

thank you, so heres the problem. i time it around 900 or 1000 rpms because of the streetport. it wont let me go lower than that, so should i set it more advanced at that rpm. it is set dead on right now with a light

Aaron Cake

iTrader: (1)

Any street port should idle fine at 750 RPM. That's one of the things that makes it a street port. I think at 1000 RPM the ECU switches timing maps so you need to keep it below there to set timing accurately.

impactwrench

I agree with Aaron on both points. My turbo glowed at idle until I leaned it out. It is a streetport that idles fine at 750RPM.

the7kid

ok if it wont idle that wrong then.....engine problem?

nitronatefc

iTrader: (2)

Do you have oil pressure? Both times I ripped my motor down to the shortblock and put it back together, the turbo glowed red, smoked, and burnt off some crap on the first restart. It went away after a minute or two. Pull the EGI fuse and crank the motor over. Does the oil pressure come up? I wouldn't go boosting down the road either until the problem is worked out. My car actually use to stumble pretty bad if I tried to to boost when the engine hadn't yet come up to operating temperature.

2-N-D-pink

iTrader: (27)

Wow. I must be some kind of retard thinking that a lean tune will cause your exhaust to rise sky high and the turbine glow. And having a bunch of gas will lower your EGT and not glow

Just curious, how does having a bunch of gas make your exhaust glow?...

the7kid

even when the motor first starts up no smoke at all. im pretty positive that it has oil pressure. i cant see right now because of the sensor but i pulled the oil filter off and theres oil there so its got pressure. wouldnt the motor have seized by now if it didnt? ive had it running several times and idling and also have drove it down the road a couple times. also with my cool clear pfa tubing i can see oil is coming up the tubes so i think thats also a sign of oil pressure.

Aaron Cake

iTrader: (1)

The fuel is now burning in the turbo, not in the engine.

Lean conditions will of course cause high EGTs. On a rotary glowing exhaust is almost always due to incomplete combustion for reasons I've mentioned.

Vacuum leak.

the7kid

im going to set the timing today at 750 and ill let you guys know how it works out.

2-N-D-pink

iTrader: (27)

Huh?




Well before I did bought injectors I had a Neo. After maxing out my stock injectors (due to 12 psi over boost) I was reading 13.3 AFR with my turbine housing glowin and kinda looking like lava. I also had my timing retarded because I really didnt want it to go boom with a bunch of advance timing. You want to explain how is this happening?

the7kid

set the timing the best i could. i think i have a vaccume leak. when i bring the idle down to 750-1000 rpms the idle fluctuates alot. i also noticed today that on idle the engine is pulling 10-12 inlb of vaccume. also it will backfire sometimes on idle and also when i drive the car and accelerate and then when i stay in the same gear and let off the car backfires several times on decel. also, the car will idle better if i retard the timing a tiny bit......sound like a vaccume leak? or any other ideas?

2-N-D-pink

iTrader: (27)

Where exactly is the mark in relation to the pointer?

Also, if you're idle fluctuates a lot between 750-1000 rpms, then you should check your TPS.

Check AFR

2-N-D-pink

iTrader: (27)

Turbo's glow, as do manifolds & downpipes. It's not a big deal & in some cases, it's a good thing. It's the nature of the hell life they live. There isn't one contributing factor that causes it. Lean conditions, type's of fuel, too much timing advance, run time, manifold design, type of materials being used, etc. will all play a role. In most cases, the hottest points are at the manifold's inlet, it's outlet & inside the turbine housing. Thicker materials will cool slower because they retain heat longer. After sprinted driving, these are the areas that normally cool slowest & contain the heat. A glowing turbo does not mean overly rich conditions, improper timing or even lean conditions for that matter. It does however mean it's hot & for good reason. Remember that the gases are in a sense, in lock down, inside the turbine housing. There is only 1 way out, & the gases must fight for that exit before it finds it's freedom.

Stick to the basics, simplicity can be beautiful. Insure safe target AFR's on each rotor. Conservative but potent timing & maintain equally cool intake temps on all rotors. With this & If you're components & workmanship are also up to par, then you're good to go. Over analyzing only creates unnecessary stress & worries. Do it right & don't be afraid to rip the snot of the these engines. It's what they are for. Enjoy yourself, smile & you're turbo glows, enjoy that too.

FC3Sdrift

iTrader: (5)

that would fall under catagory #2 "not enough timing" excessive timing retard

last week while retuning my car for 15 psi, i had it running pig rich, and had my turbo glowing bright red,now its leaned out, it takes alot of beating to get it to where it glows at all


for you guys with the street ports is there a noticable differance in the sound of your motors idling???

ITSWILL

iTrader: (12)

yes

Aaron Cake

iTrader: (1)

I'll put this another way.

If you have too much fuel or not enough timing, you are not getting complete combustion. Therefore a bunch of unburned fuel (or still burning fuel) ends up in the exhaust manifold and turbo. There it continues to burn, hence the glowing manifold/turbo.

Easy. You were at high load. Regardless of whether the mixture is too lean or too rich, the turbo will glow at high load. It's normal. You made it worse by retarding the timing greatly.

How is it a good thing, other then for neat visual effects?


The original poster is experiencing glowing turbo at idle and light load. That's certainly a problem pointing to too much fuel and/or not enough timing.

the7kid

so i set the timing and the tps and now i dont have the miss at around the 2500 mark. i now have the dreaded 3800 rpm hesitation which is ecu ground. also i have a new problem. idling at first gear i begin to let the clutch out and give it some gas and no matter how much gas i give it it has no power and bogs untill it starts to roll and gets up over about 2000 rpm. i also tried this rolling in first and there is no hesitation. i think its because of inital load on the engine. anyone know anything about it?

also when the car is warmed up it will idle like crap and not be real steady. when it is colder it runs good. no cold start or hot start problem so i dont think its any seals.

Aaron Cake

iTrader: (1)

Vacuum leak.

the7kid

its gotta be a really uncommon one because i sprayed carb cleaner all over all the intake stuff.

the7kid

quick question. is it possible to have a vaccume leak through the brake booster line. like if the check valve were in the wrong way?