slimtastic
yea dude...I rock
- Joined
- Aug 9, 2002
Who's ready for some 3800 power?!
- Thread starter GBGN1
- Start date
What would it cost for a set of headers with a T4 flange? I can make my own DP, intake, intercooler, etc etc. I could probably do the headers, but I've never built a set in my life before.
Also, I am more interested in how the wiring for this is going. I am very nervous to attempt that myself.
Also, I am more interested in how the wiring for this is going. I am very nervous to attempt that myself.
GBGN1
stroked
- Joined
- May 26, 2001
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Trannyman95
Member
- Joined
- Aug 12, 2007
NIce build thread! I know its tons of hours and work to do so props to getting the LC2 accessories and everything working on the newer engine. I chewed on this a long time ago when I built Codys GN but didn't have the ability at the time to fab the intake and a few other things that I can do now. He had a fairly new 3" downpipe from Gbody parts I believe so I just modified it a bit to move the turbo up a little and worked well, but when you are building it all from scratch that really helps and opens a lot of doors. I thought it would be great to be able to use the same existing downpipe but wasn't that simple. Looking good so far and hope it finished up great for you.
Tune wise- if you need assistance let me know. I built a hybrid GTP/Fbody file for my L67 86 Cutlass so I can use all the common L67 engine side tables and 2 bar map sensor and also run dual bank 02 sensors and 4L60E transmission. I originally just used a 98 Fbody pcm which works ok, and also what is still in Codys car and hasn't caused any issues- you are just stuck with a 1 bar map sensor. The 2004+ Supercharged Grand Prix used a smaller map sensor like the NA engines, only 2 bar, so it will clip right into that style intake.
Tune wise- if you need assistance let me know. I built a hybrid GTP/Fbody file for my L67 86 Cutlass so I can use all the common L67 engine side tables and 2 bar map sensor and also run dual bank 02 sensors and 4L60E transmission. I originally just used a 98 Fbody pcm which works ok, and also what is still in Codys car and hasn't caused any issues- you are just stuck with a 1 bar map sensor. The 2004+ Supercharged Grand Prix used a smaller map sensor like the NA engines, only 2 bar, so it will clip right into that style intake.
GBGN1
stroked
- Joined
- May 26, 2001
Thanks a lot. The tranny & PCM are both 98 before the drive by wire. With the thread you started those years ago makes total sense. I really wanted to try to use a lc2 dp but with the turbo being closer to the radiator , it made no sense. We have a old thdp were hacking up for the first design dp for this project.For the map sensor I lengthed the harness and got a correct plug end To run to the pass side fender , where I bolted the 3 bar map. When it's time to tune I'll have a hp tuner and was going to see what it was reading. We are also going with a single o2. And shutting down the other two. Then I'll be running a wb by itself also. It will be testing time soon!
The Headers are the Major PIA. If you do an ATR style like I did you will find the engine sits low in the chassis you get really close to the to the engine mount. The 3800 is shorter and narrow. A log style or TA style I think would fit best. I opted to use the stock DP putting the turbo in the same location as the Stock LC2 turbo. This was a mistake. It causes other clearance issues with the Intercooler up pipe, Throttle body, Inlet pipe, upper rad hose. Rolling the turbo forward keeping low with the profile of the engine and making the DP from scratch the way it appears in your pics is by far the best way IMO. You can clear all the items just mentioned.
20psiofevil
Active Member
- Joined
- Feb 10, 2013
Headers are a pita! I just got done building my hot side in this exact same fashion except I did it in different steps (thought ahead for a change lol). Main one being was to run the passenger side primaries to the pipe first then connect the cross-over to the driver side, then mount the turbo. I did not sweep the primaries but did angle them towards the turbo inlet at 5-10* slope. I cut the primaries that weld to the header flange all at 15* and just turned them down and forward from there. I left about 1/8" sticking through the pipe to prevent the driver side gas a clear path of entering that primary. Plus I didn't have anything to notch the tubes.
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20psiofevil
Active Member
- Joined
- Feb 10, 2013
I have a few in this thread.http://turbobuick.com/forums/threads/turbo-header-log-vs-collector-vs-ta-style.413682/
The thing I was talking about is referred to as a anti reversion cone. By allowing the primaries to stick into the 2.5" tubing instead of notching creates this anti reversion wall. The exhaust gas travels out of the motor like pictured, down the center of the pipe and then fans out and back into the combustion chamber.
The thing I was talking about is referred to as a anti reversion cone. By allowing the primaries to stick into the 2.5" tubing instead of notching creates this anti reversion wall. The exhaust gas travels out of the motor like pictured, down the center of the pipe and then fans out and back into the combustion chamber.
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I think I can help some with this. I did a lot of research on the header design a few years ago and found that a stepped exhaust system is the best way to go. 1.5" primaries on the both sides into a 2" cross over to start. About 2/3 across increase it to a 2.125" diameter. On the passenger side increase diameter to 2.5" so the exhaust will expand and let the turbo to spool better. Look at some of the stepped headers that are used in the faster Buicks and you can see what I'm suggesting.
GBGN1
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- Joined
- May 26, 2001
The headers we are building have 1 5/8 primaries with a 2 1/4 main pipe. With discussions with racers that have made big power with these engines , these sizes were optimal for a 6262 that I'm using for the build. With a much bigger turbo obviously the tube size would increase. Keeping the air velocity is key of course to a street driven car which mine will be and what we would like to produce. We will have more info soon! Cam cracked the end of the tig. I'd like to stay on subject on this thread. They will be done soon. Thanks much
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You'd be better off spending the time trying to get the turbo spooled and then trying to keep the exhaust pressure as close to intake manifold pressure as possible. There's huge power to be had in doing so. The valve timing and piston position relative to tdc is what will determine flow direction for a given cylinder more so than the header tube location and design. You're still dealing with much higher ex pressure on almost everyone of these little turbo applications. The flow is going in the direction of least resistance which happens to be backward into the intake as the piston approaches tdc on the end of the ex stroke and the beginning of the intake stroke. The piston has to go far enough down the bore to let the intake charge begin to fill the cylinder. Till this happens there is no positive flow into the cylinder and the air that's about to enter is diluted with the back flow. Reducing the ex pressure not only allows the positive flow to begin sooner but will also reduce pumping losses at the end of the ex stroke.
BPE2013@hotmail.com
slimtastic
yea dude...I rock
- Joined
- Aug 9, 2002
slimtastic
yea dude...I rock
- Joined
- Aug 9, 2002
slimtastic
yea dude...I rock
- Joined
- Aug 9, 2002
for the sake of having proper room for primaries and wanting to keep limited amounts of movement in the crossover section under the already tight oil pan. im going to incorporate the crossover into the dr side header assembly and keep the "headers" as only a 2 piece item ( as opposed to the typical buick style 3 piece headers)
