need help guys- 234whp on 50 trim

[pboglio]

Wow, those 60 ft. times are terrible, but you still trapped 104 mph, hmm. For every .10 seconds lost on your 60ft times you lose .30 seconds off your 1/4 mile times. Your running a 2.9 s 60 ft vs. 2.1 s, your losing well over 2 seconds in the 1/4 mile just from your launch. Looking at the lag your getting off the line I bet that your respool between shifts is also hurting your times and trap speeds. Every 1 second off the throttle in 3rd gear costs me about 8 mph or so, according to my logs. I'd bet your internal gate is getting kicked open during spool up. Your boost drop off from 21 psi to 17 psi makes me think wastegate blow open even more. Your compressor inlet is 3", do you have an upgraded intake pipe to match? My vote is for wastegate blow open, then exhaust manifold/turbo leak, then intake leak after that. Compression might hurt your spool up but my old 91 had 30% leakage in one cylinder and still was fast, just a little bit more laggy.

 

[bastarddsm]

you know that if it is tuned to run right on with the boost leak it will be extremely lean when the boost leak is fixed, not rich.

I say check all the vitals of the motor, compression, another boost leak, timing ( cams and ignition), and pull the plugs and look at them. If you don't have a clue what your doing as it sounds then you should probably pay someone to do it so you don't kill you motor.

 

[highintenzity4]

I have an Safc-2. Before these mods I could launch at 3k, now it only goes to 2k. Well I think the boost went to 21 to 17psi because of the boost leak. I fixed the boost leak and it is now at 21 consistent. I know I dont have an exhaust manifold leak, I put on a new manifold and gasket. How do I check for a turbo leak?

 

[pboglio]

I have an Safc-2. Before these mods I could launch at 3k, now it only goes to 2k. Well I think the boost went to 21 to 17psi because of the boost leak. I fixed the boost leak and it is now at 21 consistent. I know I dont have an exhaust manifold leak, I put on a new manifold and gasket. How do I check for a turbo leak?

Believe me, if you have a head/manifold or manifold/turbo leak, you would smell it. It smells that bad. It would also make a putt...putt noise during a quick idle rev. I don't know of any pressure tester to check a leak on the exhaust side, sorry. I would guess your setup should get you 110 mph traps. With a mind boggling slow launch your getting 104 mph, not too bad. A real launch I would think get you another 2-3 mph with 21 psi of boost, pretty close to where you should be. Intake leaks, exhaust leaks, wastegate leaks, too rich or too lean, heavy timing rollback are the only things that can really kill your spool up or power, if your supporting mods are correct. You're crank horsepower should be closer to 400 h.p. at 21 psi. A full list of your mods would help people out. Cheers.

 

[highintenzity4]

Well I checked for intake leaks, I dont have any. I havent messed with my timing. I dont smell or hear an exhaust leak. Im scared its a wastegate leak, how can I check for that?

My mods:
Pte 50trim
Fic 650cc injectors
Walbro 255hp fuel pump
Safc2
Dejon tool 3 inch intake
Adfx Fmic, Greddy Bov
Hallman pro boost controller
Turboback exhaust
Sbr exhaust manifold
Ported o2 housing(looks like it got ported slightly larger than the gasket)
Ngk 1 range colder plugs( The mechanic gapped them at 25 even though i told him 28!)
Arospeed spark plug wires

 

[pboglio]

Hmm,

Safc with 650 injectors. Might be hard controlling your timing with that thing and those big injectors. I wonder if your not getting timing rollback due to overadvanced timing, happens to me quite a bit when I go to aggressive with timing advance. Got a datalogger? If so, lets see some timing values at various rpms.

I just don't like internal wastegates, especially on something as big as what you have. I put a LOT of preload on my adjustable wastegate arm, and I have a high pressure actuator too. I would say you should thread the arm until your at least 1/4" short of the wastegate arm pin. I would assume since the turbo is new the wastegate valve would seal properly. Only way to tell for sure is to pull it off the car and you don't want to do that. A heavy preload usually seals that baby nice and good. You'd be suprised how much they leak even with a light preload off of the car, now imagine exhaust gas pushing on it.

Also, just for kicks. Try and tee your Hallman boost controller onto the throttlebody or something OTHER than the CBV or fuel pressure regulator. I've had my 1 gen CBV valve hang open slightly and cause a slow spoolup. This was with an intake check that looked good up to 25psi, how that happened I have now idea. Fixing it made a big difference in part throttle spool up. A cheap way to check is grab an old credit card and mount it inbetween your CBV and the mount, then clamp it all down. Go for a drive and see if your part throttle spool up gets better. Don't drop the throttle, just roll back out of it slow.

Its always intake/exhaust/wastegate leaks, bad ignition timing, or rich/lean air fuel ratios. There is nothing else other than major obstructions in the intake/exhaust path. I could probably PM you with a list of quick fixes just so you can try stuff out. Cheers.

 

[pboglio]

I just checked your profile. You never mentioned having an automatic. I can see why your having trouble. How can you stand the lag with that 50trim? Who ever recommended that turbo to you for street duty didn't do you a favor. Looks more like a highway killer setup than a dragster.

This sounds like blasphemy but: Order up a .48 A/R ratio turbine housing for your particular turbine wheel. I doubt you will lose any of your top end right now since you're NOWHERE near the limit of either turbine housing anyway. You'll be surprised how much snappier the bottom end will be. When you get past 400 crank h.p. you can always put your .63 A/R housing back on, no big deal. I did the similar thing on a 16g, traded the 7cm housing for a 6cm turbine housing, worked wonders. I think you MIGHT be able to do a turbine housing swap without even pulling the exhaust manifold, just drop the downpipe and undo 4 manifold/turbo bolts and one v-band clamp. Cheers.

Gene

 

[44pirate]

you know that if it is tuned to run right on with the boost leak it will be extremely lean when the boost leak is fixed, not rich.

I say check all the vitals of the motor, compression, another boost leak, timing ( cams and ignition), and pull the plugs and look at them. If you don't have a clue what your doing as it sounds then you should probably pay someone to do it so you don't kill you motor.

The MAS measures how much air is coming into the engine, the ECU matches fuel for that amount of air, boostleak means you will not have the same amount of air going into the engined that the MAS measured, hence more fuel then air measured=rich.

 

[highintenzity4]

I dont know if turbo lag is that much of a difference. The takeoff is really, really slow. But what explains that I can only launch at 2k now instead of the previous 3k? I doubt I have a boost leak now, the car is hitting 21 psi consistently. Maybe I should go get dynotuned again now that I have fixed the boost leak. After my burnout the car felt like it was going to die down. Maybe it is the tuning.

P.s
my car is auto but on the dyno he floored it at around 3500 rpm when the turbo was spooling, so eventhough i should have got a higher hp number

 

[lowridin2g]

I want to get dynotuned yesterday and the car dynoed at 234 even with proper tuning.

your turbo definetly fell off dude























im j/k, thats just the dick in me. i would say your wastegate is blowing open too soon or staying semi open always. or u may have a boost leak or 2 or 3. also tune that bi*** better

 

[highintenzity4]

Well Im hitting 21 psi now, so I dont know if I have a boost leak? So if my wastegate is damaged what can I do and how do I know if it is messed up?

 

[PieTSI]

Its been mentioned many times. Do a boost leak check. www.vfaq.com is your friend. You can make a tester for under $10.

 

[blcknspo0ln]

a boost leak doesn't mean that you're not going to be able to make boost.. it's just that the turbo is working HARDER to make that same amount of boost as if it were boosting without a leak.

instead of waiting for replies i suggest what everyone else does.. COMPRESSION, INTAKE, MAINTENANCE checks are all vital, and should be your base diagnosing..

 

[pboglio]

a boost leak doesn't mean that you're not going to be able to make boost.. it's just that the turbo is working HARDER to make that same amount of boost as if it were boosting without a leak.

instead of waiting for replies i suggest what everyone else does.. COMPRESSION, INTAKE, MAINTENANCE checks are all vital, and should be your base diagnosing..

I agree 100%. Its obvious you might be over your head from your responses, even though it seems simple to the rest of us. Bring your car to a shop and give them a SHORT list of the ideas you got here. Preferably a DSM shop.

 

[highintenzity4]

Well most of the stuff seems simple, my dad is a mechanic at Rush Peterbuilt so I am quickly learning. We are new to DSM's, so I come here for some pointers and ideas. We already checked for boost leaks, we did a compression test and a leakdown test, and the maintenance is good. Things that are difficult for us is the tuning, so we went to a local shop who has a dyno. There is no DSM shops here!. If we cant work out the bugs, Im going to a DSM shop somewhere in Texas and ask them to check out the car. Thanks for all the input guys. Hey about the wastegate semi-opening, how could we find out?

 

[Zex4g63]

I have a similar set up what are your karman readings on the SAFC? What O2 housing? Have you messed with the adjustable wastegate? If not give it one full turn. Do not try to brake boost if you are using the stock torgue convertor. By the time it begins to build boost the TCU will be pulling the timing out of the car. By theway do you have a logger and what does the timing look like. It is critical on an auto. You do not need to change turbo or any part of it. Using the stock convertor allows your GST toget rolling before making real power. IF you make real boost fron a dead stop, you will need a higher stall convertor and slicks to hook it up. My PTE bigins to build boost at 2600rpm and is all in by 3200rpm. Please check out the auto forum on this sight and ATDSM

 

[anconover]

so you asked for the plugs to be gapped to .028, and were gapped to .025 and you never fixed it?

 

[highintenzity4]

Well yea like a day later I regapped them. When I was doing the compression test, I noticed that he gapped them at .025.

 

[PieTSI]

a boost leak doesn't mean that you're not going to be able to make boost.. it's just that the turbo is working HARDER to make that same amount of boost as if it were boosting without a leak.

instead of waiting for replies i suggest what everyone else does.. COMPRESSION, INTAKE, MAINTENANCE checks are all vital, and should be your base diagnosing..

I've had boost leaks that would make the boost fall off by redline. Anyways...I would check to see that your wastegate works properly. Make sure its closed all the way, by taking the arm off and checking. Then make sure it opens right by taking off the vaccume line to the nipple of the wastegate actuator, putting an air compressor line on it and slowly turn up air pressure from zero on the air compressor. It should open when it hits whatever psi your wastegate is designed to open at. Do not try to put like 30psi on this actuator, you will break it, slowly turn it up from zero.

 

[Easton6985]

at what rpm are you guys seeing 21lbs? i have a similar situation. 50trim stock internals, dynotuned and made 304 whp. fixed all the boost leaks. the main problem with mine is that it doesnt spool until 5k. it starts to spool at around 3-3.5 where is should but when everyone elses shoots up to 20 mine takes its sweet ass time getting up there and then stays at 20 at about 5000rpms. im going to do a compresion check on it tonight and see how that is. i also tightened the wastegate arm, so i know its not stayin open.

 

[Joesmoke]

I may have missed something in the post, but can you check your knock / timing?

Timing being yanked way back due to knock, either real or false, would give you about that much power.

 

[espinelli]

Sounds like you took care of the boost leak issues. Although, I don't think your boost leaks would cause the performance issues your experiencing.

I would rule out the waste gate actuator. Here's an unsafe way of doing but you'll be okay if your careful.

Extend the actuator which will make gate seal nice and tight if you already haven't.
Next, disconnect your wastegate vac line. Take it for a quick spin, nail it, and keep an eye on your boost gauge. You obviously don't want to hit excessively high boost. Evaluate your results and let us know what happened.

 

[highintenzity4]

Hey guys I did the wastegate test and it is working properly. I did find one problem though, instead of connecting the factory boost solenoid to prevent the cel, I took it off. I got a cel. I dont know what I did with it, so I relayed a signal to where the factory boost solenoid is suppose to connect to and the cel came off. Now the car runs like crap, at 4,500 rpm it sounds like Im getting fuel cut. Can someone give me some Karman settings on hi-throttle and low throttle so I can know moreless?

 

[Endz0r]

sounds like you are getting fuel cut?

you will feel fuel cut. it's like the gods decided that ur car was going to fast and decided to slam the brakes.

 

[myblack98gst]

okay, here is one suggestion no one has made and has worked for me a couple of time. but My car is odd.


It deff. sounds like you have timing issues to me. Try disconnectiing your battery for a couple of minutes to clear the ECU out. then try it again..


one day my car for no (known) reason at all started running BAD I mean it would not spin the tires in first gear under full boost (18 psi) and it normally shreds them in second.
It continued to run this bad till I reset the ECU. and it started running just fine again..