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Only making 125hp on the dyno? Let's double that!!!
- Thread starter Chad989of2000
- Start date
Chad989of2000
Well-known member
Jesus that's scary ^^^...so after I remove the cat and if that's ruled out...I'll take of the exhaust mani and turbo, check all passages and replace gaskets. It just sucks when I can't do something my self on the car, you know like the 4 wheel alignment and actual dyno it's in the shop now for and a tech insists that the issue is of course a more expensive item (such as a turbo) which is most likely NOT the suspect. So Saturday will be a cutty/diaassembly kind of day.
bazeng
Well-known member
Sounds like a timing issue.
A good way to check if it is your exhaust is weld a nipple on the exhaust and run a boost gauge off it.
You should not be seeing much pressure after the turbo at all.
Stock cars see about 6psi or so.
A good way to check if it is your exhaust is weld a nipple on the exhaust and run a boost gauge off it.
You should not be seeing much pressure after the turbo at all.
Stock cars see about 6psi or so.
Olson
Well-known member
^ or buy a cheap timing light..... and check your timing marks on your cam gears
^ This! Like I was saying earlier. 1947 had a similar issue once upon a time.
Chad989of2000
Well-known member
Holy shat...turbo is creeping like a sex starved pedo...it would boost creep from 8psi to 24psi /ubbthreads/images/graemlins/ooo.gif Exhaust side and wastegate flapper area is already ported...Guess too much air is rushing out the exhaust and not through the wastegate. Thinking about going external wastegate to fix this, plus I've heard they're pretty nice to run.
Jostar
Well-known member
You sure you have mechanical timing is dead on? & base timing? My galant Once jump 15 teeth & barely slapped the valves & it ran really loe low on power...
boostedinaz
Well-known member
Quoting Chad989of2000:
Holy shat...turbo is creeping like a sex starved pedo...it would boost creep from 8psi to 24psi /ubbthreads/images/graemlins/ooo.gif Exhaust side and wastegate flapper area is already ported...Guess too much air is rushing out the exhaust and not through the wastegate. Thinking about going external wastegate to fix this, plus I've heard they're pretty nice to run.
An external dump may not completley cure the issue just keep that in mind.
Holy shat...turbo is creeping like a sex starved pedo...it would boost creep from 8psi to 24psi /ubbthreads/images/graemlins/ooo.gif Exhaust side and wastegate flapper area is already ported...Guess too much air is rushing out the exhaust and not through the wastegate. Thinking about going external wastegate to fix this, plus I've heard they're pretty nice to run.
An external dump may not completley cure the issue just keep that in mind.
jepherz
Staff member
Quoting Jostar:
You sure you have mechanical timing is dead on? & base timing? My galant Once jump 15 teeth & barely slapped the valves & it ran really loe low on power...
Me too.
You sure you have mechanical timing is dead on? & base timing? My galant Once jump 15 teeth & barely slapped the valves & it ran really loe low on power...
Me too.
prove_it
Well-known member
I did a timing belt six years ago and when I went to drive it, something wasn't right. I could still get up to speed and drive on the interstate, but it just had no power. Checked everything over and found my intake cam was one tooth off.
Nice thing about turbos is that if your intake cam is off, the air will still get crammed in and it will run decent enough to think it's something else. It's probably one of the quickest things to check, and while your checking the cam timing pull your CAS and make sure to line it up so you know for sure that the CAS and Cams are all aligned properly.
Way easier than replacing all the exhaust gaskets, which I doubt is where your issue lies. An exhaust leak pre turbo would cause very slow or a lack of boost, and a post turbo leak would only yield a sound.
Make sure that when you do find the problem, throw some new spark plugs in it too.
Nice thing about turbos is that if your intake cam is off, the air will still get crammed in and it will run decent enough to think it's something else. It's probably one of the quickest things to check, and while your checking the cam timing pull your CAS and make sure to line it up so you know for sure that the CAS and Cams are all aligned properly.
Way easier than replacing all the exhaust gaskets, which I doubt is where your issue lies. An exhaust leak pre turbo would cause very slow or a lack of boost, and a post turbo leak would only yield a sound.
Make sure that when you do find the problem, throw some new spark plugs in it too.
Jostar
Well-known member
Quoting jepherz:
Quoting Jostar:
You sure you have mechanical timing is dead on? & base timing? My galant Once jump 15 teeth & barely slapped the valves & it ran really loe low on power...
Me too.
Hey welcome to the club... lol..
Quoting Jostar:
You sure you have mechanical timing is dead on? & base timing? My galant Once jump 15 teeth & barely slapped the valves & it ran really loe low on power...
Me too.
Hey welcome to the club... lol..
Chad989of2000
Well-known member
Cat was not clogged, a little nasty, but not the culprit. Used a timing light, checked both mechanical and ignition timing, it was set at 5 degrees just like it should, nothing was off with these checks. Gonna go ahead with the external waste gate, but first will check the exhaust and waste gate flapper areas of the turbo to see if it was maybe ported too aggressively. Had timing off with 989 once and the car was really lazy on the acceleration. My car feels slow now, but it feels NA slow, when my other car's timing was off it felt like a vTec but with no upper end pick up. Gonna go Tial 44mm which should be pretty compatible with my setup.
Barnes
Well-known member
Tial 44mm for a E3-16g? Are you trying to run 1 psi of boost? A 38mm should be fine. Are you looking to upgrade later?
correct me if Im wrong,
but to properly set mechanical timing, you must have access (with the lower timing cover off) to the timing marks for the crank's T-belt pulley, have those lined up with the marks on the front cover while at the same time have both the cam gears in the same orientation with the dowel pins up and all four notches in the gears lined up parallel and on the same plane as the mating surface of the valve cover and the head. rotate the crank with a ratchet 6 times to verify everything all lines up still.
Am I right to say that you cannot use a timing light to set mechanical timing? and in order to truly verify if it's correct you have to pull most of your accessory pulleys and belt and lower timing cover?
but to properly set mechanical timing, you must have access (with the lower timing cover off) to the timing marks for the crank's T-belt pulley, have those lined up with the marks on the front cover while at the same time have both the cam gears in the same orientation with the dowel pins up and all four notches in the gears lined up parallel and on the same plane as the mating surface of the valve cover and the head. rotate the crank with a ratchet 6 times to verify everything all lines up still.
Am I right to say that you cannot use a timing light to set mechanical timing? and in order to truly verify if it's correct you have to pull most of your accessory pulleys and belt and lower timing cover?
Chad989of2000
Well-known member
^^^Yup that's the procedure for checking the mechanical timing. The timing light helps check ignition timing, which is a far quicker check. All marks lined up as the engine was just installed less than 3000 miles ago. After removing the lower timing cover I was relieved to see how clean it was, back in the day 989 had a leaky cam shaft seal that leaked down on the timing belt causing it to fail prematurely and bending all my exhaust valves in the process. The Belt is still in excellent condition on this car. I suspect the porting on the turbo to be the issue now...as I've ruled out other possible gremlins. Yeah, and I'll be opting for the 38mm Tial External. Thanks again for the input.
Like you already know engines = air pumps. Air in, air out.
Had similar issue, found the rubber donut around the turbo intake had folded over and choked off the compressor. Could boost to 15psi but took forever and felt slow while doing it.
Also had a bad PCV valve ( Framinator ) cause problems like that, mani would read 17psi but pushed a bunch of pressure into the crankcase.
Had similar issue, found the rubber donut around the turbo intake had folded over and choked off the compressor. Could boost to 15psi but took forever and felt slow while doing it.
Also had a bad PCV valve ( Framinator ) cause problems like that, mani would read 17psi but pushed a bunch of pressure into the crankcase.
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Chad989of2000
Well-known member
Yeah I mistakenly installed a Fram one once...didn't even function right...been oem ever since...plus the price difference isn't even an issue...think it was under a $5 difference between the Fram PCV and the Oem piece. The littlest things sometimes.
