STS/ Rear mount owners...In here now!
Scott... you are seeing increased spool in part do to displacement I think.
Enjinjoe are you running a intercooler? If your spraying meth your IAT's shouldnt be that bad??? I think 4.11's are part of your problem, you run out of gear too fast... with a turbo car you want that 3000-6000 rpm range to last (it is where your power is). I am only running 3:50 gears.
Hissin... I would save the money for something else...
My concept for my 408 build is going to be to ceramic coat all my hot parts all the way to the turbo... I may even wrap on top of that as well. I want to maintain as much heat and speed as possible at the turbo... gotta get that 76 to spin up!!
Enjinjoe are you running a intercooler? If your spraying meth your IAT's shouldnt be that bad??? I think 4.11's are part of your problem, you run out of gear too fast... with a turbo car you want that 3000-6000 rpm range to last (it is where your power is). I am only running 3:50 gears.
Hissin... I would save the money for something else...
My concept for my 408 build is going to be to ceramic coat all my hot parts all the way to the turbo... I may even wrap on top of that as well. I want to maintain as much heat and speed as possible at the turbo... gotta get that 76 to spin up!!
i know a guy here in town who has a stock exhaust STS setup with a GT67 , A4 and i walk away from him, im running 5.5 psi and he runs
7-8 - ive got headers and a 3 inch exhaust, so im not buying into the stock exhaust is better crap. ive talked with STS extensively and they cant say stock is better than LT, all the cars with LTs and tuned right are running the better times, from previous threads.
7-8 - ive got headers and a 3 inch exhaust, so im not buying into the stock exhaust is better crap. ive talked with STS extensively and they cant say stock is better than LT, all the cars with LTs and tuned right are running the better times, from previous threads.
Originally Posted by longrange4u
Enjinjoe are you running a intercooler? If your spraying meth your IAT's shouldnt be that bad??? I think 4.11's are part of your problem, you run out of gear too fast... with a turbo car you want that 3000-6000 rpm range to last (it is where your power is). I am only running 3:50 gears.
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2000 and up manifolds hold heat better. That might be a factor. Also the factory system up to the int pipe seals really well. headers are more prone to leaks especially around the collector area.
I think 2000 and up stock manifolds and a 2.5 inch ORY pipe and int pipe (Y and int pipe heatwrapped) would keep the most heat in the pipe and allow for faster spool (all else being equal)
I think 2000 and up stock manifolds and a 2.5 inch ORY pipe and int pipe (Y and int pipe heatwrapped) would keep the most heat in the pipe and allow for faster spool (all else being equal)
I have a pretty good STS set up it in my sig thanks to Billy at TRT great place to do buisness with. My only gripe right now is my air temps do the same as the guys above no matter how cool it is they stay around 120 with a intercooler anyone have insight on that? One other thing is I have a #15 spring in and no matter what I am only seeing at most 13 with a T-70-.81
Originally Posted by BJM
The traditional header designs for N/A cars seems to hurt turbo motors. You have a much larger internal volume in a long header than a manifold, more to fill. You also slow the flow down with larger pipes.
Originally Posted by Zombie
The volume you need to fill doesn't matter, it takes about .01 sec to fill the pipes, it's the surface area the radiates all the heat which creates volume which creates more pressure. The flow slowing doesn't matter either. You build pressure in the pipe. The turbo is the cork in the system, the pipe will never flow more than the turbo will allow.
I wish we could do a temp measurement from the top of the y pipe to the inlet of the turbo at RPM. Then we could quantify the benifit of coating, wrapping, blanket vs: temp.
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Verdad Gallardo TECH Senior Member
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Turbos need heat to spool quickly. The more heat you can keep in the pipe that faster it'll spool. That is why you can see 80RWHP difference on the dyno from early pulls versus later pulls when the turbo is still cold.
It'll make a big difference
It'll make a big difference
Thread Starter
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From: North Las Vegas, NV
Originally Posted by CHRISPY
Turbos need heat to spool quickly. The more heat you can keep in the pipe that faster it'll spool. That is why you can see 80RWHP difference on the dyno from early pulls versus later pulls when the turbo is still cold.
It'll make a big difference
It'll make a big difference
Jon and I did a quick math section last night and realized that using headers vs manifolds, we were getting close to doubling the surface area of exhaust tubes/pipe which inturn would lead to heat loss. He is going to try coating everything since the guys with jet hot coatings on their headers AND ypipe seem to not be having this issue. Time will tell and we will see what happens with this.
Jeremy is going back to stock as far as I know and we'll see how that goes.
Personally, since I'm running only 348ci, I could care less on the type of manifolds/etc as long as the turbo spools up like 'normal'.
Originally Posted by longrange4u
Someone needs to take a before and after temp check of exhaust of a "warm" engine 3000 rpm's at the turbo inlet. That would be amazingly helpful!
My main reason for doing the swap is ground clearance. SLP's can't clear a flattened out coke can. I know if I took a big speed bump really slow I could high center it.
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From: North Las Vegas, NV
Originally Posted by longrange4u
Someone needs to take a before and after temp check of exhaust of a "warm" engine 3000 rpm's at the turbo inlet. That would be amazingly helpful!
My car is in another state and still tore apart otherwise I'd do it.
and mine has a blown head gasket... trying to decide if I want to spend 6 k to rebuild all and have a solid 10 sec car... or 12 k to shoot for a 9 sec car. Man this sport is expensive
Yeah I know the feeling mine is torn apart also. But in a question about heat and flow. I had my uncle custom make me some Iron shorties. Iron holds heat better than alumin. I will get pics as soon as he sends them. But he says they look like jba shorties. The primaries are 1 5/8 to help flow. Should I coat these? If so with what? Also the ypipe I should have that Iron also? The headers where free and If i need the y done it will be free also. I will post a test of the differance between the custom system and ps long tubes wrap up. To see if the extra weight gains are worth it.
I have headers on mine and spooling is not an issue. The slightest exhaust leak makes a world of a difference though. The band clamps on my headers had just a slight black line from the split in the pipe. I put better clamps on it and the boost was up much faster. I run 10psi and can have full boost by 3600 which is just above the converter speed.
I also played with exhaust housings. A larger exhaust housing was worth a few MPH at the track even though the small housing would spool faster. I have the 67 turbo.
I also played with exhaust housings. A larger exhaust housing was worth a few MPH at the track even though the small housing would spool faster. I have the 67 turbo.
Thread Starter
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From: North Las Vegas, NV
Originally Posted by red91z
I have headers on mine and spooling is not an issue. The slightest exhaust leak makes a world of a difference though. The band clamps on my headers had just a slight black line from the split in the pipe. I put better clamps on it and the boost was up much faster. I run 10psi and can have full boost by 3600 which is just above the converter speed.
I also played with exhaust housings. A larger exhaust housing was worth a few MPH at the track even though the small housing would spool faster. I have the 67 turbo.
I also played with exhaust housings. A larger exhaust housing was worth a few MPH at the track even though the small housing would spool faster. I have the 67 turbo.
Joined: Jun 2004
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From: Ft. Irwin, California (But Virginia is home)
I'm pretty sure that LT's are a limiting factor in producing boost due to heat dissipation. I currently am running DynaTech LT's (ceramic coated) with the DynaTech pro-flo cats. I get crap for positve pressure until the exhaust is hot..... and am lucky to get a steady 5PSI then. I'm running a FMIC and have the boost reference at the intake, not the turbo.
I've spoken extensively with Billy at TRT (great source of info BTW.
) One conclusion is that wrapping the exhaust in heat wrap would decrease boost spool times and help overall boost pressure. I'll be changing heads (after my unwanted deployment to Iraq) and I'll probably put the stock manifolds back on at that time. The only good thing about LT's is the gain when puttering around daily driving at low RPM's when boost is never really a factor.
BTW, I don't make positive pressure till about 3400RPM and don't have full boost till 4.5K. In 1st gear I hit about 3.5 to 4PSI and then it spikes to 4.5 to 5 PSI from 2nd gear on up. By 4th gear it's more or less a full on 5PSI.....but who drives around WOT in 4th gear unless at the track?
I've spoken extensively with Billy at TRT (great source of info BTW.
) One conclusion is that wrapping the exhaust in heat wrap would decrease boost spool times and help overall boost pressure. I'll be changing heads (after my unwanted deployment to Iraq) and I'll probably put the stock manifolds back on at that time. The only good thing about LT's is the gain when puttering around daily driving at low RPM's when boost is never really a factor.BTW, I don't make positive pressure till about 3400RPM and don't have full boost till 4.5K. In 1st gear I hit about 3.5 to 4PSI and then it spikes to 4.5 to 5 PSI from 2nd gear on up. By 4th gear it's more or less a full on 5PSI.....but who drives around WOT in 4th gear unless at the track?
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From: North Las Vegas, NV
Originally Posted by Schantin
I'm pretty sure that LT's are a limiting factor in producing boost due to heat dissipation. I currently am running DynaTech LT's (ceramic coated) with the DynaTech pro-flo cats. I get crap for positve pressure until the exhaust is hot..... and am lucky to get a steady 5PSI then. I'm running a FMIC and have the boost reference at the intake, not the turbo.
I've spoken extensively with Billy at TRT (great source of info BTW. ) One conclusion is that wrapping the exhaust in heat wrap would decrease boost spool times and help overall boost pressure. I'll be changing heads (after my unwanted deployment to Iraq) and I'll probably put the stock manifolds back on at that time. The only good thing about LT's is the gain when puttering around daily driving at low RPM's when boost is never really a factor.
I've spoken extensively with Billy at TRT (great source of info BTW.
) One conclusion is that wrapping the exhaust in heat wrap would decrease boost spool times and help overall boost pressure. I'll be changing heads (after my unwanted deployment to Iraq) and I'll probably put the stock manifolds back on at that time. The only good thing about LT's is the gain when puttering around daily driving at low RPM's when boost is never really a factor. i would be interested in knowing what times at the track , and dyno numbers you guys are getting now with LT and what it is when you switch to the stock exhaust headers.?? i dont care what some engineer THINKS will happen we need proof!!!!