New TE44 turbo install. Fluttering at 12 psi, why?

[Fast Farmer]

Seems to be a common thread emerging here. Every one of you fellas that are having problems with this surging are running a much larger than stock intercooler. I use a Duttwieler neck ic, and it is smooth as silk. Could it be an issue of too much internal volume for these relatively small turbos mentioned?

 

[bison]

Seems to be a common thread emerging here. Every one of you fellas that are having problems with this surging are running a much larger than stock intercooler. I use a Duttwieler neck ic, and it is smooth as silk. Could it be an issue of too much internal volume for these relatively small turbos mentioned?

The compressor is running in surge at low throttle angles regardless of the intercooler. The throttle blade is not open all the way and the turbine speed is trying to cram a higher mass flow of air into the engine which it can't use because the throttle isn't open and it is reverting. Smaller a/r ex housings increase this. Smaller a/r ex housing increase response which is more important than anything on a street applications. As far as small it's enough to support 10 sec power yet most won't and don't crack 11.50. In that case something else is even smaller.

 

[bison]

If I had my TA 49 set to "kill" (23 psi), the part throttle surge would hammer me out of the car. The car is a light switch: all on or all off. If a honda wants to race me on the street I waive him off, because I can't "take it easy" on him.

If a Tornado stops that on the street, I would recommend a Tornado. The Surge my car has would eventually break a lot more than the turbo. It can't be doing the trans, converter, u-joints, etc. any good.

The Solution for me is to turn the boost down on the street and go slower.

Those are interesting theories but no evidence to back them up anywhere. Kind of like when someone says they would have been dead in a car collision if they were or weren't wearing their seatbelt. Well they did or didn't wear it and they are still alive so it's just speculation.

 

[TurboBob]

there is a solution other than the tornado which will help some of the cars.

the idea is to program the chip to leave the boost solenoid off until you get harder into the throttle than the surge point (2.5v or so)

You can't do it if you have an MBC (like the RJC boost adjustment gizmo).

On some cars it will fix it, others it won't. Its relatively easy to try since you likely have all the hardware already on the car.

Bob

 

[we4Mateo]

My surge was bad enough at part throttle to throw the airflow numbers off and my car would buck and what have you from going too rich from not taking the flow the MAF was seeing. The tornado fixed it. The alky brought it back though, same psi as everyone else, but even with alky, the surge was less to the point that the chip at least didn't alter fueling enough to make it run bad. The Bailey chip helps too as it ignores super high MAF readings and smoothes the operation of the motor under a part throttle surge situation. I tried my Bailey chip without the tornado though, b/c of this feature, and it still made my car buck under certain surge situations. I know the tornado is just acting like a "cork" with holes in it in the air intake, but the problem is solved. I don't take the tornado out at the track either and I still trap over 118. I'm hoping to see 120mph, even with the tornado in, if I can ever get my boost back up to 25psi, so it can't be hurting the flow that bad; at least on a stock headed car like mine. I too will have a ported housing in my next turbo though, but that's a ways off. The 44 rocks on the street and is plenty for me at the strip too due to my love of cheap/stock 109 rotating assemblies.

 

[Fast Farmer]

The compressor is running in surge at low throttle angles regardless of the intercooler. The throttle blade is not open all the way and the turbine speed is trying to cram a higher mass flow of air into the engine which it can't use because the throttle isn't open and it is reverting. Smaller a/r ex housings increase this. Smaller a/r ex housing increase response which is more important than anything on a street applications. As far as small it's enough to support 10 sec power yet most won't and don't crack 11.50. In that case something else is even smaller.

That's funny. Bison, pm me your recommended recipe for a 10 sec. car with a TE-44. Thanks.

 

[mgmshar]

Seems to be a common thread emerging here. Every one of you fellas that are having problems with this surging are running a much larger than stock intercooler. I use a Duttwieler neck ic, and it is smooth as silk. Could it be an issue of too much internal volume for these relatively small turbos mentioned?

You could be right. However, I am pretty sure that part of the reason I was able to do 119 mph in the quarter on 100 octane unleaded without alky is because of my intercooler. I don't have it in my mind to sacrifice that performance.

I know that some people have gone tens with TA49's. It can be done. Tin Man went tens with a stock unopened engine, and I think the first time was with a TA49 and CAS V2. We used to chat a lot in our club since our combos are very similar. Basically, you run it at really high boost, like 26 or 27 psi, have a really good IC, exhaust, and gas. Even with a stock engine, it can get there.

Later this summer, I'm planning to remove the MBC and start using a MAFTPro and solenoid. I'm going to try what Bob and I mentioned above and leave the solenoid unactuated until my throttle is open wider than the surge point. If it works, I'll post back.

Mike
Sent from my HTC Droid Incredible using Turbo Buick

 

[we4Mateo]

I don't think the intercooler matters. Just depends on what your engine can eat. 20psi at the throttle body is the same regardless of what intercooler it comes from. A cooler charge is denser though and that does make surge worse. Point is, with alky, my stock intercooler, dutt neck intercooler, and CAS V4, all surge at the same psi. The surge is gone without alky though using any of the three intercoolers mentioned. I've never compared to a front mount yet all else being equal.

 

[krom]

Mine would only surge when I put in a 3500 stall, did not do it with a 3000. I learned how to peddle the gas the same way I had to learn my first drive by wire truck.

 

[Fast Farmer]

You could be right. However, I am pretty sure that part of the reason I was able to do 119 mph in the quarter on 100 octane unleaded without alky is because of my intercooler. I don't have it in my mind to sacrifice that performance.

I know that some people have gone tens with TA49's. It can be done. Tin Man went tens with a stock unopened engine, and I think the first time was with a TA49 and CAS V2. We used to chat a lot in our club since our combos are very similar. Basically, you run it at really high boost, like 26 or 27 psi, have a really good IC, exhaust, and gas. Even with a stock engine, it can get there.

Later this summer, I'm planning to remove the MBC and start using a MAFTPro and solenoid. I'm going to try what Bob and I mentioned above and leave the solenoid unactuated until my throttle is open wider than the surge point. If it works, I'll post back.

Mike
Sent from my HTC Droid Incredible using Turbo Buick

Hey Mike, maybe because I bypass the solenoid is why I don't have a surge problem. I just have a hose going from the compressor straight to the actuator. I use a HD actuator to control boost. works for me.

 

[UNGN]

Those are interesting theories but no evidence to back them up anywhere. Kind of like when someone says they would have been dead in a car collision if they were or weren't wearing their seatbelt. Well they did or didn't wear it and they are still alive so it's just speculation.

I've broken drivetrain parts on my Pontiac 2+2 from on/off oscillations that were a lot less violent than the part throttle surge in my T-type.

It's one of the easier ways to break stuff, if you are trying to break stuff.

500lbft of torque switched on/off @ 2 Hz isn't doing anything any good.

 

[UNGN]

I don't think the intercooler matters. Just depends on what your engine can eat. 20psi at the throttle body is the same regardless of what intercooler it comes from. A cooler charge is denser though and that does make surge worse. Point is, with alky, my stock intercooler, dutt neck intercooler, and CAS V4, all surge at the same psi. The surge is gone without alky though using any of the three intercoolers mentioned. I've never compared to a front mount yet all else being equal.

I agree. Mine surges with a dutweiller neck stocker.

 

[TheGovernment]

Can someone throw up a link for the air foil on ebay? I can't seem to find it. My car is just a street driver. I'd like to try it out, if just for driving back and forth to work.

thanks!

 

[bison]

That's funny. Bison, pm me your recommended recipe for a 10 sec. car with a TE-44. Thanks.

You can search Around and find that info. Several have done it. I've seen it in signatures. All from what I remember ran boost in the high 20's,24-26* advance and had decent air, and had a decent working suspension. 10.90's@122. Someone went 10.80's on an unopened about 10 years ago. The combo was in the gsxtra back then. if someone built a purpose built combo they could probably squeak it into the 10.70's without nitrous in really good air.

 

[bison]

I've broken drivetrain parts on my Pontiac 2+2 from on/off oscillations that were a lot less violent than the part throttle surge in my T-type.

It's one of the easier ways to break stuff, if you are trying to break stuff.

500lbft of torque switched on/off @ 2 Hz isn't doing anything any good.

It's not 500ftlbs switched on and off. The engine only has a chance to swallow what gets past the throttle blade. If you want to put money on it I'll take my car and put one of these turbos on it and wire the throttle so it cant open and surges as much as possible and I'll run the car on a dyno with an electric brake until the brake is too hot to operate. I'll just hold it there for 3 minutes if the dyno brake doesn't over heat. I can do a graph showing that there is no interruption in torque also. $500 or more bet.

 

[mgmshar]

To be fair to everyone here, when my car goes into the surge at moderate throttle, the boost gage is around 11 psi or so. That means there is 11 psi in the intake manifold, which means the engine is making what, maybe 200 ft-lbs or something? When my turbo goes into surge, the engine bucks very noticably at the same frequency as the surging. My guess is that is due to air flow reversion through the MAF - you can actually see the MAF readings oscillating up-and-down while the surge is happening on my DS screen (yes, I still use DirectScan). Because the MAF is wildly changing readings, the fueling is wildly changing, and the engine bucks back-and-forth. If you are not running a MAF, you might not notice this phenomenon.

I can't imaging that the engine bucking back-and-forth enough that I can feel it in the car is good for parts. I also can't imagine that it's bad enough that parts will be instantly destroyed, either.

To the above point - I can get my turbo to spool up enough just sitting in Park and revving the engine that when I release the throttle, I get an extended period of surging (or sneezing or whatever you want to call it). Even under those conditions, if I have the hood open, I can see the engine bucking back-and-forth a little bit due to the above phenomenon. Same for when I'm on the road and I follow moderate accelearation with a throttle lift - I hear the turbo surging (sneezing) for a long time, and depending on how hard I was accelerating, I can feel the engine bucking while sitting in the car, even though the throttle is completely closed. I believe, again, that this is due to flow oscillations through the MAF causing rapid fueling changes in the engine. Now, I have had this issue for years, but to my knowledge, I haven't broken anything yet.

Maybe when I go to the MAFTPro and eliminate the MAF, the engine bucking will be reduced or eliminated, since flow reversions through the MAF will be eliminated. Otherwise, maybe moving the MAF to the uppipe (ala Bob Bailey style) will accomplish the same goal.

Curious - anybody running a combo similar to mine without a MAF (some kind of speed-density system like MAFTPro or XFI)? Can you comment on engine bucking while the turbo is surging?

Thanks,

 

[Flyin Brian]

Mine did not surge with stock IC. After installing the FMIC I have surging at part throttle near 12 psi but my intake air temperature at the throttle body is WAY down with the FMIC so I am getting more air into the motor. If I feel the surge I just roll into the throttle more and it goes away. A better sized turbo should fix this someday but that is a long way off.

 

[TurboBob]

with speed density, when you hear the surging, you don't feel it.

I have not run a blow-thru MAF, that was Bruce Plecan. Its an interesting setup, but has its own set of tuning quirks.

Bob

 

[mgmshar]

with speed density, when you hear the surging, you don't feel it.

I have not run a blow-thru MAF, that was Bruce Plecan. Its an interesting setup, but has its own set of tuning quirks.

Bob

Sorry Bob and Bruce, had a case of CRS there.

Thanks for your feedback on the speed-density effect on this, that's what I thought might happen.

Thanks,

Mike
Sent from my HTC Droid Incredible using Turbo Buick

 

[BobbyBuick]

Back in 1998 I fixed mine with a 3.00 spring from ace hardware,Still on the car.that's how the old timers did it