What would cause me to lose HP?
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TECH Apprentice
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From: Fort Worth, TX
What would cause me to lose HP? Ok first off its a 402 stroker with a APS kit. The shop Tuning my car dyno'ed it 3 times @ 14 psi and put down 720rwhp. They added 1 degree of timing and lost 60ish rwhp put the timing back in it and did the same pull @ 14psi and lost 200 horsepower. Took the intake charge pipe off and found that the turbine wheel had some play in it. Today I went and checked the passenger side and that wheel seemed to have a little less play than the driverside one. On the driverside one I can push the turbine wheel and the blades will touch the casting walls. Is that normal to be able to do that? Otherside didn't move that much. SO my questions is, will the turbo not make anymore boost with that much play there for making me lose HP?
FormerVendor
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From: Hell AFB
Ok first off its a 402 stroker with a APS kit. The shop Tuning my car dyno'ed it 3 times @ 14 psi and put down 720rwhp. They added 1 degree of timing and lost 60ish rwhp put the timing back in it and did the same pull @ 14psi and lost 200 horsepower. Took the intake charge pipe off and found that the turbine wheel had some play in it. Today I went and checked the passenger side and that wheel seemed to have a little less play than the driverside one. On the driverside one I can push the turbine wheel and the blades will touch the casting walls. Is that normal to be able to do that? Otherside didn't move that much. SO my questions is, will the turbo not make anymore boost with that much play there for making me lose HP?
The best thing to do would be to look at the essentials.
1. You made 14psi regardless
2. Check spark plugs for any signs of anything
3. Leak it down, 200hp is ALOT.
Some turbos do have side/side shaft play, obviously there is a spec for these.
Do you currently have catayst converters? If so, check them out for clog, this is a HUGE loss in hp.
Just remember, if it doesnt look right and it doesnt smell right, something is not right
I posted about play on mits turbos in another thread. Some side to side play is normal in these but don't think it should scrape the sides. Front to back play its not supposed to have much at all.
As said if you are holding 14psi then it don't seem to be turbo problem. They seem to be making boost. Boost leaks can take away a lot of hp but if its getting to the engine then you should be ok there. You can check for leaks with automotive smoke machine. That is best way from my experience.
There is something terribly wrong with losing 200hp as was said. One degree of timing would not think would do much. We do need to know your afr on the runs and your timing numbers.
Oh sorry too many guys and threads. You are running clutch or auto? If clutch then it might be slipping past 700 or so. If auto they are harder to get good numbers on dynos ,think especially non load bearing types. Or maybe auto is also not up to the power. What dyno is this on?? dynojet,mustang?
Remember 720 rwp is well over 800 engine hp on standard and like 900 on auto at 20% loss.Thats not bad really . Still I was hoping to see 850rwhp out of my kit and engine. Waiting to do my car is killing me but at least get the benefit of you guys doing yours first and any potential problems coming to light.
Are you seeing any oil out the exhaust? Any white smoke?? Your engine is brand new correct? I would think it also needs to break in a bit. I assume you gapped the plugs down to .035 or so? think that is what most fi guys are running and at least one heat range cooler. Was this run on pump gas? Any alc/meth injection? Maybe you are getting tons of knock retard stealing away your power?
As said if you are holding 14psi then it don't seem to be turbo problem. They seem to be making boost. Boost leaks can take away a lot of hp but if its getting to the engine then you should be ok there. You can check for leaks with automotive smoke machine. That is best way from my experience.
There is something terribly wrong with losing 200hp as was said. One degree of timing would not think would do much. We do need to know your afr on the runs and your timing numbers.
Oh sorry too many guys and threads. You are running clutch or auto? If clutch then it might be slipping past 700 or so. If auto they are harder to get good numbers on dynos ,think especially non load bearing types. Or maybe auto is also not up to the power. What dyno is this on?? dynojet,mustang?
Remember 720 rwp is well over 800 engine hp on standard and like 900 on auto at 20% loss.Thats not bad really . Still I was hoping to see 850rwhp out of my kit and engine. Waiting to do my car is killing me but at least get the benefit of you guys doing yours first and any potential problems coming to light.
Are you seeing any oil out the exhaust? Any white smoke?? Your engine is brand new correct? I would think it also needs to break in a bit. I assume you gapped the plugs down to .035 or so? think that is what most fi guys are running and at least one heat range cooler. Was this run on pump gas? Any alc/meth injection? Maybe you are getting tons of knock retard stealing away your power?
Ok sorry looked at your old posts..you have clutch and had to change out clutch? What clutch do you have now? clutch can easily make one lose a lot of hp and sometimes be inconsistent. And again what make of dyno. What afr and timing were you seeing? May have to scan the car during dyno runs.What plugs and gap? What fuel system again is it sufficient? Shame my car is not done as we could compare numbers on my 408 to your 402 and we have same heads and both m6 cars. Unfortunately only mustang dyno within 150 miles of me .Dynojet is more like 500 miles and will be getting dynojet not mustang at some point.
I would be running an incar scanner like scanmaster so could really keep tabs on the important stuff like knock retard,timing,etc. Laptops are not so good to use all the time.
Wonder if the maf is maxing out. Are you using speed density now.
I would be running an incar scanner like scanmaster so could really keep tabs on the important stuff like knock retard,timing,etc. Laptops are not so good to use all the time.
Wonder if the maf is maxing out. Are you using speed density now.
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TECH Apprentice
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From: Fort Worth, TX
Ok we changed out the clutch to a RAM Twin disk, fuel is Lonnies duel pumper kit, Plugs are NKG TR6 I believe, gapped at .35, Dyno is a DynoJet. I'm still using a MAF and I dont have the dyno run sheets. I beleive they told me the AFR was different side to side, which also caused a RED Flag. This shop deals with alot of turbo cars, so I beleive them when they say my turbo is on its way out.
Today I will pull a plug out and check it and do a leak compression test on it. I'll also to a leak down test aswell on the boost lines.
Would it be in my best interest to do Speed Density now? And what type of gauge should I put in my car to look at the vital signs of the car when under boost.
Today I will pull a plug out and check it and do a leak compression test on it. I'll also to a leak down test aswell on the boost lines.
Would it be in my best interest to do Speed Density now? And what type of gauge should I put in my car to look at the vital signs of the car when under boost.
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Verdad Gallardo Lots of guys like to have egt guage,in car fuel pressure and in car realtime scanner like ls1s1 scanmaster,msd dashawk think its called?. Boost of course and vac can be handy sometimes.
Are you seeing oil out the side of the looser turbo? either side? Any white smoke. White of course would be from head gasket.Did you retorque headgasket? Some need retorque ,some don't.
Auto smoke machine is best way to find leaks in piping,etc. Would think though that if you are holding boost steady your hp should be steady also. What fuel octane.mabye pulling lots of timing do to knock? Does the new clutch maybe need some break in miles before it holds good? Just trying to throw out some ideas for you.
Hopefully you get this figured out.
Were you getting wheelspin on the dyno.Thought it was hard to hook this type of power up on the dyno sometimes?
Are you seeing oil out the side of the looser turbo? either side? Any white smoke. White of course would be from head gasket.Did you retorque headgasket? Some need retorque ,some don't.
Auto smoke machine is best way to find leaks in piping,etc. Would think though that if you are holding boost steady your hp should be steady also. What fuel octane.mabye pulling lots of timing do to knock? Does the new clutch maybe need some break in miles before it holds good? Just trying to throw out some ideas for you.
Hopefully you get this figured out.
Were you getting wheelspin on the dyno.Thought it was hard to hook this type of power up on the dyno sometimes?
Joined: Jun 2004
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From: Ft. Irwin, California (But Virginia is home)
Ok we changed out the clutch to a RAM Twin disk, fuel is Lonnies duel pumper kit, Plugs are NKG TR6 I believe, gapped at .35, Dyno is a DynoJet. I'm still using a MAF and I dont have the dyno run sheets. I beleive they told me the AFR was different side to side, which also caused a RED Flag. This shop deals with alot of turbo cars, so I beleive them when they say my turbo is on its way out.
Today I will pull a plug out and check it and do a leak compression test on it. I'll also to a leak down test aswell on the boost lines.
Would it be in my best interest to do Speed Density now? And what type of gauge should I put in my car to look at the vital signs of the car when under boost.
Today I will pull a plug out and check it and do a leak compression test on it. I'll also to a leak down test aswell on the boost lines.
Would it be in my best interest to do Speed Density now? And what type of gauge should I put in my car to look at the vital signs of the car when under boost.
I'd definetly swap to SD mode. 2-bar for up to 14.7lbs boost and 3-bar for up to 29.4lbs. I'm not sure at what point the MAF is maxed out, but you are probably close to it (if not already past it). The 2&3 bar SD tune models will let you set PE for boost/non-boost regions individually as well as allow you to alter VE cells for partial and full boost cells. The 2/3bar SD helps to create a nice smooth HP/TRQ curve w/ a fairly stable AFR.
For gauges, a WB O2 is a must. I have had great luck w/ the AEM unit, but there are other good ones too. Fuel pressure is also a biggie. EGT would be useful for a TT setup like yours, but in my $0.02 not as important as fuel and air. Boost gauge....well, I have one but to be honest I rarely check it. I'm looking at the AFR and fuel pressure when WOT, not the boost gauge. It's impossible to monitor too much crap at once when going flat out, so I stick w/ the important ones.....
Hope this heps you a bit. Take care
Rotating assy scraping on the housing = problems.
There should/will be some play, as the turbo is not under oil pressure when U R checking it.
Big diffs on AFR bank to bank could = a turbo that's **** up.
There should/will be some play, as the turbo is not under oil pressure when U R checking it.
Big diffs on AFR bank to bank could = a turbo that's **** up.
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TECH Apprentice
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From: Fort Worth, TX
Well I have a Eboost2 gauge and Electric Fuel Pressure as of right now. The car only blows out Dark (black) smoke.
They did say it spun the clutch when doing a 720 pull but they let it cool down. I've got about 80 miles on it now. ALso the clutch is hard to get into 1st and reverse. What is the cause for that?
They did say it spun the clutch when doing a 720 pull but they let it cool down. I've got about 80 miles on it now. ALso the clutch is hard to get into 1st and reverse. What is the cause for that?
200hp is a huge loss. Which way did the AF ratio shift? If it became rich, I would guess you lost 1 or more plugs. If is leaned out, I would guess you lost one or more injectors or the fuel pump is going out. You really need a wideband 02 on it. If the two runs had the same boost level 14 psi, but difference levels in horsepower, then I will have to totally disagree with "This shop deals with alot of turbo cars, so I beleive them when they say my turbo is on its way out.". I do not think it is the turbo or that the shop deal with a lot of turbo cars.
Keith
Keith
Well if the clutch is slipping it could lose a lot of power.The problem with the 1st and reverse means the clutch is not adjusted right and you are not getting proper disengagement. Doesn't your ram use an adjustable master? If it does you better get that adjusted right away. I had a cartech clutch ruined in only a thousand miles or less from the modified gm master not working right. Car was way way down on power of course . Mph was pathetic. Thats one reason I went with textralia this time ,they use stock hydraulics. But Peter at APS think said they went thru two tex twins already. I may have to go to the triple or mabye try a spec twin. Think they also use a stock hydraulic setup.
That ram might be fine but set it right away. You climb under dash and adjust rod longer until it can go in far enough into master to let the gears disengage properly. Just keep making rod longer and stop when it goes into 1sts and reverse nicely. Of course this also assumes you have things bled well. And you might have to change adjustment a little bit again as you gain some miles.
As for fubar turbo..I posted that some movement is normal on these mits side to side. And as said without oil flowing thru it might seem worse. With twins its harder to see if turbo is going as assume the other one will just take up the slack. If your boost is holding 14psi steady I can't see hp going away. That would take ridiculous knock retard to lose 200hp! And afr even pig rich doubt it would take away that much power. You need to get wideband on there asap. And scan it also while driving around.
But my money if the boost stays at 14psi is clutch issues again. Sorry you don't want to hear that I know. Remember 720 rwhp is like 870 engine. Whats the ram supposed to handle.and they usually rate by torque not hp.
That ram might be fine but set it right away. You climb under dash and adjust rod longer until it can go in far enough into master to let the gears disengage properly. Just keep making rod longer and stop when it goes into 1sts and reverse nicely. Of course this also assumes you have things bled well. And you might have to change adjustment a little bit again as you gain some miles.
As for fubar turbo..I posted that some movement is normal on these mits side to side. And as said without oil flowing thru it might seem worse. With twins its harder to see if turbo is going as assume the other one will just take up the slack. If your boost is holding 14psi steady I can't see hp going away. That would take ridiculous knock retard to lose 200hp! And afr even pig rich doubt it would take away that much power. You need to get wideband on there asap. And scan it also while driving around.
But my money if the boost stays at 14psi is clutch issues again. Sorry you don't want to hear that I know. Remember 720 rwhp is like 870 engine. Whats the ram supposed to handle.and they usually rate by torque not hp.
Well if the clutch is slipping it could lose a lot of power.The problem with the 1st and reverse means the clutch is not adjusted right and you are not getting proper disengagement. Doesn't your ram use an adjustable master? If it does you better get that adjusted right away. I had a cartech clutch ruined in only a thousand miles or less from the modified gm master not working right. Car was way way down on power of course . Mph was pathetic. Thats one reason I went with textralia this time ,they use stock hydraulics. But Peter at APS think said they went thru two tex twins already. I may have to go to the triple or mabye try a spec twin. Think they also use a stock hydraulic setup.
That ram might be fine but set it right away. You climb under dash and adjust rod longer until it can go in far enough into master to let the gears disengage properly. Just keep making rod longer and stop when it goes into 1sts and reverse nicely. Of course this also assumes you have things bled well. And you might have to change adjustment a little bit again as you gain some miles.
As for fubar turbo..I posted that some movement is normal on these mits side to side. And as said without oil flowing thru it might seem worse. With twins its harder to see if turbo is going as assume the other one will just take up the slack. If your boost is holding 14psi steady I can't see hp going away. That would take ridiculous knock retard to lose 200hp! And afr even pig rich doubt it would take away that much power. You need to get wideband on there asap. And scan it also while driving around.
But my money if the boost stays at 14psi is clutch issues again. Sorry you don't want to hear that I know. Remember 720 rwhp is like 870 engine. Whats the ram supposed to handle.and they usually rate by torque not hp.
That ram might be fine but set it right away. You climb under dash and adjust rod longer until it can go in far enough into master to let the gears disengage properly. Just keep making rod longer and stop when it goes into 1sts and reverse nicely. Of course this also assumes you have things bled well. And you might have to change adjustment a little bit again as you gain some miles.
As for fubar turbo..I posted that some movement is normal on these mits side to side. And as said without oil flowing thru it might seem worse. With twins its harder to see if turbo is going as assume the other one will just take up the slack. If your boost is holding 14psi steady I can't see hp going away. That would take ridiculous knock retard to lose 200hp! And afr even pig rich doubt it would take away that much power. You need to get wideband on there asap. And scan it also while driving around.
But my money if the boost stays at 14psi is clutch issues again. Sorry you don't want to hear that I know. Remember 720 rwhp is like 870 engine. Whats the ram supposed to handle.and they usually rate by torque not hp.
I would try an RPS twin disk they are the ferrari of twin disks. Costs a pretty penny, but they are fully rebuildable even the flywheel is. You pay big up front then only 400 per rebuild.
Ok we changed out the clutch to a RAM Twin disk, fuel is Lonnies duel pumper kit, Plugs are NKG TR6 I believe, gapped at .35, Dyno is a DynoJet. I'm still using a MAF and I dont have the dyno run sheets. I beleive they told me the AFR was different side to side, which also caused a RED Flag. This shop deals with alot of turbo cars, so I beleive them when they say my turbo is on its way out.
Today I will pull a plug out and check it and do a leak compression test on it. I'll also to a leak down test aswell on the boost lines.
Would it be in my best interest to do Speed Density now? And what type of gauge should I put in my car to look at the vital signs of the car when under boost.
Today I will pull a plug out and check it and do a leak compression test on it. I'll also to a leak down test aswell on the boost lines.
Would it be in my best interest to do Speed Density now? And what type of gauge should I put in my car to look at the vital signs of the car when under boost.
An 8 MINIMUM is what i'd run with a non projected tip and .028 gap.
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TECH Apprentice
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From: Fort Worth, TX
Ok I'll get the clutch fixed and I should get NEW plugs is that right? What kind and gap them at .28????
I'm sure the RAM is suppose to hold what I'm putting at it. I'll have to find out what the numbers are.
Valve float surely not. My cam isn't that big, Comp 918s would work for the cam but I have a dual spring on it right now.
But I was driving it around today and around 6K it seemed not to pull as hard as in the lower RPM's..??
I'm sure the RAM is suppose to hold what I'm putting at it. I'll have to find out what the numbers are.
Valve float surely not. My cam isn't that big, Comp 918s would work for the cam but I have a dual spring on it right now.
But I was driving it around today and around 6K it seemed not to pull as hard as in the lower RPM's..??