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Reply With Quotethats hot !
wowowowow!!!
thats hot !
Nice spike in between shifts :P
Looks like it pulls descent for 5 psi!
Favorite part: "OH SHIT!" haha why such a cool comment?
7g for life!
More! please more!
8G 4 life!
Mods: CAI,Grounding wires, CCorners, Shaved, 3G STB. AGX/Teins, Addco bar, OZ F1 wheels And well maintained : )
Welcome to boost, brother :twisted:
that was the first time i had seen anything over 2psi on his car.....I WAS EXCITED OK SETH?Originally Posted by seth98esT
Thanks for the comments you guys.
Progress report:
Ok after installing the gaskets w/grease on them, and rerouting the downpipe to the atm, the turbo was able to produce considerably more boost. Now while we did hit 5 psi (we used to spike to 4 psi), we still need to track down the other 4 psi (some of it may simply be due to inefficient manifold design and a larger turbine housing).
Also I experienced my first detonation yesterday. After pulling over to fix a blown coupler (4th or 5th time within a few miles ~ t-bolts on the way), I got on it trying to chase after a C6. Within a second of going WOT, we heard what sounded like a gun shot. We decided to call it quits right there. And drove the car home (nothing sounded/felt abnormal). I'm yet to pull the plugs.
I will have to check out the video after work...dayam firewall here!
Anyways...the "detonation" you experienced when did it happen again? You said you WOT..but did you watch if you redlined? Sometimes when I redline I will get that "gun shot" noise too. When you turbo...sometimes you don't realize how fast the car goes through the RPM's so before you know it you redline. If thats so...that is just some misfire making that noise. Well...I hope so least.
1991 Galant VR4 1948/2000_________1996 Galant "S" 5 speed 2.4L turbo
yeah with no cats,
when you hit the rev liimiter(spark arrest)
there is still a super rich mixture and what happens is the fuel ignites in the manifold, or downpipe.
(thats why you see cars with straight through exhausts like gsx's or wrx's spit fire between shifts!!!
knock is actually more of a PING.
i used to use just plain wheel bearing grease to help seal gaskets.... it worked...
but nothing works as well as copper spray.
______________________________
1994 Galant GS-Turbo
Sweet! I've joined the shooting-fire-from exhaust club. :D
Ya I can't afford copper gasket. In fact I can't afford new gaskets. I'm reusing the same gaskets from my car that I've been using for the last 120k miles.
Honestly I can't remeber exactly when it happened. It might have been right after shifting. I didn't realize that misfires can be so loud. Though it makes perfect sense considering that I have about 2 feet of 3" piping. And for that matter, I saw no change in driving habit. Considering that it happened after the 5th run, AND after let the car sit for a while, the whole exhaust system was probably hot as shit. Enough so to reignite the rich leftover.
Cheesy video I made:
http://videos.streetfire.net/video/da548f8...83600ecede0.htm
Could be fuel cut? Stock injectors still right? Ive hit fuel cut a few times during a WOT 3rd gear pull. Its sooooooooooooo loud, feels like hitting a brick wall.
Or it could just be excess fuel being ignited in your exhaust. Turbos are fun though :)
7g for life!
Well as far as I can remeber, I was still pulling during the misfire. So I don't think it was fuel cut.
When I hit fuel cut, er, following Brandon on the freeway, it didn't make any noise, or anything, so don't think that would be it. Brandon had also hit fuel cut many times, that one day
Ah not fuel cut then. From my experience and readings, fuel cut will feel like you hit a brick wall, followed by a very loud backfire which comes from the engine bay and not out the tailpipe.
Its actually kind of scary haha.
7g for life!
Like what Seth said..turbo's are fun. Don't worry man...when I first heard that "gun shot" sound from the car that scared and worried the crap out of me. I finally realized it was good ol' rich backfire..but none the less, it was effin LOUD. Its actually pretty fun especially when the backfiring happens and so happens a car is next to near to my exhaust side. I think I scared a few drivers since they kinda swirve from being probably startled.
I think I got video somewhere of the backfire fun....if I can find it, i'll post it up.
1991 Galant VR4 1948/2000_________1996 Galant "S" 5 speed 2.4L turbo
Holy crap dude! I though that fuel cut could potentially lead to big problems? BTW Do you have any more footage of your car?When I hit fuel cut, er, following Brandon on the freeway, it didn't make any noise, or anything, so don't think that would be it. Brandon had also hit fuel cut many times, that one day
Ya dude I got to say that gun shot scared the hell out of me. While I was flooring it, there was an old man on the other side of the street. I didn't want to frighten him or anything (BoB makes me respect anyone who looks like they fought in WWII), but as I passed him BOOM! Felt kinda sorry for the guy. I mean it was loud enough inside the cabin. I can imagine that it was loud enough outside to be heard for a good half mile.
Haha ya I can imagine that it begins to be pretty entertaining. I've seen the backfire a million times on various vehicles, but never actually heard it. I can't wait to start spitting out flames. :laughing: In all honesty, I'm not entirely worried about blowing my engine. I have another one sitting in my garage right now. And for that matter I won't be driving my car for about 3 months while I'm off at school.
I would really like to see your video of the backfire.
I found the video this morning...so I am going to see if I can make a quick vid of it. The car doesn't shoot out flames..but you can hear the back fire. Didn't realize how rich I was running either...lots of black smoke
Here you go Jet Black...I posted the video here:
Backfire vid
1991 Galant VR4 1948/2000_________1996 Galant "S" 5 speed 2.4L turbo
Thanks for the video dude. While I can't say that mine sounded anything like that, I believe this is simply due to different circumstances. That is, 3 feet of 3" open dump DP, and first time hearing it.I found the video this morning...so I am going to see if I can make a quick vid of it. The car doesn't shoot out flames..but you can hear the back fire. Didn't realize how rich I was running either...lots of black smoke
Here you go Jet Black...I posted the video here:
Backfire vid
So right now my two biggest problems are:
1) Still ZERO boost in 1st gear.
2) Couplers popping off, EVERY single time I boost (t-bolts will be arriving ONE day before I'm leaving my car behind).
The first problem seems to be directly related to several factors:
a) Massive exhaust restriction. A turbo that is basicly meant purely for top end does not respond well to my 2.25" stock catback (3" DP). I gained anywhere from 1-3 psi by simply removing the stock exhaust.
b) Oversized exhaust housing from the start. .96 AR is not a street trim. I'm planning on going to other end of the spectrum with a .69 AR. The .96 I will save for the other motor. Quite a few turbo 3Gs are using .63 AR T3s for the exhaust.
c) Vacuum leaks: I determined that the biggest source of vacuum leaks must be the couplers. Considering that they pop clean off at a mere 5 psi, they are probably bleeding boost well before then. Though the seals in the intake manifold is also suspect.
d) Poor turbo manifold design. The rear bank (bank #1) has a good 2-3 feet of extra piping before it reaches the collector. The front bank only has about 6" of travel till the collector. And on top of that, the collector is another foot to the flange. I imagine that this causes atleast some backpressure for the rear bank. Also inside of the manifolds themselves, their are PLENTY of stalagmites, and "metal envelopes" (from overlapping pipes ~ my fault) for the gasses to get trapped in. With the new engine, I will be totally redoing the whole manifold setup. If I can't have equal length, I will atleast keep the two banks seperate till the flange.
Anyways, I found some information that confirmed some of my thoughts on the issue of turbo lag:
<div class='quotetop'>QUOTE</div><div class='quotemain'>A given turbocharged vehicle may produce full boost in first gear by 3500 rpm. This same vehicle may produce full boost in 4th gear by 2300 rpm. The same vehicle, when pulling a heavy trailer, may produce full boost by 1800 rpm even in 1st gear. These conditions are more specific to manual transmission vehicles as the boost has to build in each gear after the throttle is closed during the shift. Automatic transmission vehicles operate differently as they can be "loaded" by stalling up the converter and placing enough load to build boost before the vehicle even moves. Also, with an automatic transmission, the throttle is not shut during shifts which causes the boost to "pop up" because the turbo is supplying enough air flow to feed the boosted engine at high rpms and suddenly the rpms are drastically cut down by the shift as well as increased load has been placed on the system at the same time. This can cause an engine that is accelerating in 1st gear with low boost to instantly go to full boost upon shifting into 2nd gear.</div>
http://www.ststurbo.com/turbolag
I'm presuming that the ends of the pipes where the couplers are blowing off are not beaded - I have no clue how you would go about getting that done, but having beaded pipe ends would help with the couplers problem.
For sure it would. I'm considering doing some ghetto-beads with my welder. A few spot welds, and some grinding down should suffice.
Though in the bigger picture, I want to eliminate as many couplers as possible by welding them together.
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