24v Quest for 550+HP experianced oppinions welcomed!

[PhReE]

Nope, nobody is saying go R32, honestly that has it's own set of problems (breaking parts! instead of breaking traction).

Just making sure your expectations are set correctly, but honestly, you dont NEED 550 whp. You can make that GTI faster than your CBR600 withOUT building the motor. You can have a lot of fun with just a headgasket spacer motor. These motors are so tough it's ridiculous. I have over 80,000 boosted miles on my headgasket spacer'd motor and the problems I am running into now are with the chassis, suspension, bushings, etc. The motor? Perfect.

[.SLEEPYDUB.]

why would it be retarted??? sure it wont be a stop light to stop light car but she'll be a beast from 40mph and up

40mph and up? With that kind of power you are looking at not having traction till over 100mph, and thats with a nice drag radial setup. With 600+whp, I wouldnt catch traction at all, in any gear, it was completely pointless. I only drove it like that once, and i never did it again because its pointless.

I had a big ol response typed up, and I lost it. Just watch this. This is about 400whp. Can you imagine 150whp more?

[joeeveryman87]

Touche' Touche' and WOW! thats 400whp?? thats insane power man i didnt realize thats all you'd need for that performance.......

[PhReE]

Touche' Touche' and WOW! thats 400whp?? thats insane power man i didnt realize thats all you'd need for that performance.......

That's pretty much what we have all been trying to say.

[joeeveryman87]

That's pretty much what we have all been trying to say.

Im sorry i was taking it the wrong way, thought you guys were telling me a fwd car is a waste of time to upgrade, def seeing that video puts some different/cheaper thoughts in the back of my head, thank guys!

[joeeveryman87]

Guess you can say im a "visual" learner thanks again

[.SLEEPYDUB.]

No problem man. Theres not very many good videos out there showcasing what a real street vrt is like. That one puts it into perspective.

[RmL1.8T]

There's a boatload of great info in this thread. Good stuff guys. Subscribed.

[joeeveryman87]

No problem man. Theres not very many good videos out there showcasing what a real street vrt is like. That one puts it into perspective.

So the video def caught my attention and i have a couple questions, what turbo and clutch setup did you go with, what did the spacer drop your compression down to(any issues with it?), and did you install an LSD? or atleast have an oppinion on pelequin or wavetrac LSD perfromance on the O2J tranni......

[.SLEEPYDUB.]

So the video def caught my attention and i have a couple questions, what turbo and clutch setup did you go with, what did the spacer drop your compression down to(any issues with it?), and did you install an LSD? or atleast have an oppinion on pelequin or wavetrac LSD perfromance on the O2J tranni......

Turbo is T4 35R with a 1.06AR turbine housing.
No spacer, fully built schimmel block.
Autotech wavetrac diff, on my 2nd one. Broke the diff, 4th gear, and a bunch of other **** in the tranny all at the same time doing a 4th gear pull on low boost.
No experience with Peloquin, although ive heard nothing but good things from them.

O2J? Did you mean O2M?

[joeeveryman87]

Well ive been workin on a few projects in the past couple weeks so i figured id post some pics, ill start with my boser hood extension we welded on and painted last week, turned out pretty good enjoy

[joeeveryman87]

Turbo is T4 35R with a 1.06AR turbine housing.
No spacer, fully built schimmel block.
Autotech wavetrac diff, on my 2nd one. Broke the diff, 4th gear, and a bunch of other **** in the tranny all at the same time doing a 4th gear pull on low boost.
No experience with Peloquin, although ive heard nothing but good things from them.

O2J? Did you mean O2M?

Yes sorry i did mean O2M, so the wavetrac is good then? why did you have such bad tranni issues? is the O2M weak?

[joeeveryman87]

And you wonder why the whole front end is pulled off in those??? because i also installed some 264/260 TT cams i got brand new for $500 with a C2 flash









annnnnnnnd Cams installed....

[joeeveryman87]

This is the new hood with the old bumper still on, i bought an aftermarket R32 bumper and a rieger 1bar grill and we plastic "welded" it to the bumper.



This "custom" bumper was kind of a bitch but we finally got it and primed it last night, check it out.....



and finally me rockin the new roof rack with my kayak , also its hard to see but you can see that we all shaved the handle off the hatch and i installed a popper left the emblem though still gotta rep you know!?!

[.SLEEPYDUB.]

I liked the wavetrac, just didnt like that it broke on me...when just using 4th gear, but hey **** happens

[D03GLIR]

Yeah man, that's sick. I thought near 300 was fun but VRT is the champ-
Nice drivin.........
You convinced me, over 400 HP is just a waste w/ these cars.....but fun nonetheless (Gee officer, I wasn't out of 4rth yet, can I catch a break?).

[BakBer]

Yes sorry i did mean O2M, so the wavetrac is good then? why did you have such bad tranni issues? is the O2M weak?

You saw the video right?

[joeeveryman87]

You saw the video right?

yesssss......

[.SLEEPYDUB.]

It should be obvious then. Catching traction suddenly while your tires are spinning in excess of 100mph, just isnt good for gears...

[GTIVRon]

To be completely honest, I've learned that the VR6 is a hell of a motor for boosting. The rest of the car sucks total ass. Transmission isn't built for much power. Yet to find a mount that somebody hasn't broken or don't have to replace with practically every oil change (the design behind the mounts are just not meant to take the abuse). The chassis sucks, heavy and sloppy.

I get you like the car... It's just a very crappy platform to build a monster from. Do a search for VRT's and check all the "for sale" threads. People do it, learn FWD sucks for power/learn the car just can't handle it, and then go for a platform that can sustain the power goals they have.

I really like VW, and will more than likely always have one on my drive way (Buying a MK6 4dr Golf TDI soon), but I'm sad to admit I don't think there will ever be a quality platform for high power under the VW badge. That's why I'll be selling my car after I get my DD, and be buying domestic V8 for a project/weekend warrior.

[One Gray GLI]

still haven't sold the car, and I'm closing in on four years now, 3 of them turbo'd. granted I have another car or two now also. No point in selling it, it's not worth what it once was, and I don't owe anything on it, and it still puts a smile on my face.

If you put a decent set of tires on the car, it'll hook. obviously not in the winter or in the rain, but during the spring/summer, depending on where I go WOT in the rpm range, I can get the car to hook by the end of second, and that's at 470whp.

Like I've said..the breaking point on these cars is in excess of 500whp. after that, along come the trans issues, then motor issues if it's just got a HG spacer. As I've said in the past, there's no point to having THAT much power for a FWD street car. long WOT pulls in 4th/5th will destroy your trans, and the heat created by those "longer pulls" isn't so great either.

you don't want tranny problems? go buy a quaife gear box and spend >4k at least.

[joeeveryman87]

hmmm so many things to think about............ i still think ill build up the motor and slap a goos sized turbo in her, just might lower the power goals a slightly

[joeeveryman87]

finished

[joeeveryman87]

An intercooler would look soooooo sexy in that bumber.......just sayin

[.SLEEPYDUB.]

Im going to be taking my 16psi wastegate spring out of my TIAL and run a 7psi spring like I did back when I first turboed the car. It was tamable, and Ill actually be able to catch traction enough to tune the car how I want to. NOT LIKE A RACECAR!! God I hate that my car is just an on/off button with power

[joeeveryman87]

Im going to be taking my 16psi wastegate spring out of my TIAL and run a 7psi spring like I did back when I first turboed the car. It was tamable, and Ill actually be able to catch traction enough to tune the car how I want to. NOT LIKE A RACECAR!! God I hate that my car is just an on/off button with power

how much psi can you run to your engine off a 7psi spring as opposed to a 16psi? or is it just 7 or 16psi total that you can run alltogether....meaning if i wanted to run 30lbs of boost i would need a 30psi spring for the wastegate?

[.SLEEPYDUB.]

oh man, you need to do some more research if you dont know the answer to that question.

The psi associated with a wastegate spring is the minimum amount of boost the wastegate will allow the turbo to produce. It wont go under ~7psi and wont go over ~7psi unless the wastegate has a boost controller hooked up to it. In theory you usually can only going about 15psi over the wastegate pressure. So a 7psi spring will allow for up to ~22psi. However I have seen some people go above that range, but thats usually a good safe estimate. Youll get at least 22psi out of a 7psi spring.

I used a 16psi spring because I was running 28psi+ and a 7psi spring wouldnt allow me to go that high.

[joeeveryman87]

oh man, you need to do some more research if you dont know the answer to that question.

The psi associated with a wastegate spring is the minimum amount of boost the wastegate will allow the turbo to produce. It wont go under ~7psi and wont go over ~7psi unless the wastegate has a boost controller hooked up to it. In theory you usually can only going about 15psi over the wastegate pressure. So a 7psi spring will allow for up to ~22psi. However I have seen some people go above that range, but thats usually a good safe estimate. Youll get at least 22psi out of a 7psi spring.

I used a 16psi spring because I was running 28psi+ and a 7psi spring wouldnt allow me to go that high.

see i learn sm new everyday , im learning and know most of the operations of the turbo setup as a whole, but as for individual stuff, i may know what they do in general, but not so much specifics. So thanks for the wastegate 101 , thats exactly why i started this thread gotta love Vortex man!

[joeeveryman87]

I always thought, the bigger the better than you can just get a boost controller and turn it down when you dont want it and turn it up when you do, but not so much......?

[.SLEEPYDUB.]

You can only turn it down as far as your wastegate allows. ie; a 7psi wastegate cant go lower than 7psi, but it can go higher.

[joeeveryman87]

You can only turn it down as far as your wastegate allows. ie; a 7psi wastegate cant go lower than 7psi, but it can go higher.

Thanks buddy

[joeeveryman87]

So i did some research cause i was dissapointed about not knowing what waste gates are really all about and i found this interesting and very informative post on an Evo Forum enjoy!!!
hey guys, i just got a call from a guy that I dont believe is on this forum or anything but we had a conflicting conversation about what size wastegate he needed to use on his subaru. He told me that he did a ton of research and he said he wanted to run high boost and that a 38mm wastegate would not be enough for 30+ psi on a GT35R.

First of all, just to put it out there, wastegates LOWER boost, meaning that the lower boost you run, the more of the wastegate you use.

Below is a turbo and how it works basically. The red side is the exhaust side, the blue side is the compressor side. The 2 wheels are connected by a shaft. Exhaust gases turn the exhaust wheel which is attached to the shaft that is attached to the compressor wheel. The compressor wheel sucks in air and compresses it, forcing it through the intercooler pipe and into the engine.



Below is a turbo setup in color. There is no wastegate on this setup. Consider the red tube to be a header or exhaust manifold. With no wastegate on that tube, boost would keep going up and up with rpm to whatever the turbo could produce because the engine would just keep producing more and moer exhaust gases. Now if you put a wastegate on that tube its basically going to act like a controlled exhaust leak and its going to leak out exhaust gases before they can reach the exhaust wheel. The more you leak out, the less the exhaust wheel will turn; creating less boost.



Now heres where we get technical. wastegates will open up to whatever spring pressure the spring inside is because The vacuum line thats hooked up to the lower port has the pressurized air going through it to the gate under the valve assembly forcing it open. Basically if you have a 14.5 psi spring in your gate and everything else is working properly, when you floor your car, your turbo will create 14.5 psi of boost and once theres 14.5 psi of boost in your engine/intake manifold, that means theres 14.5 psi of boost going through that vacuum line. once 14.5 psi of boost hits the wastegate it forces it open, thus bleeding off exhaust and maintaining the amount of exhaust it takes to turn the exhaust wheel to create 14.5 psi. Now imagine we install a manual boost controller in the vacuum line between the intake mani and the wastegate. Now we have another controlled leak. If we leak off 4 psi before the wastegate sees it, then the motor is going to have 18.5 psi in it when the wastegate sees 14.5 psi. As we bleed off more air through the boost controller the boost will go up and up because the wastegate isnt seeing that 14.5 psi yet.

here is a link to a pdf file that shows how all of the above works
http://www.tialmedia.com/documents/w..._wginstall.pdf


Now lastly, there are other factors that will effect boost levels.

Boost creep and cars not reaching the desired boost level are other problems people have.

Scenario 1. If you have a 38mm wastegate on a 8.0L viper which obviously has a ton of exhaust and you want to run 3 psi of boost well whats gonna happen? The gate is gonna maxxed out and the exhaust gases are just gonna turn the exhaust wheel faster and faster creating more boost then desired.

Scenario 2. Imagine we put a stock subaru turbo on a dodge viper with a four 44mm gates with a 3 psi springs. Now we want to run 20 psi of boost and we have a boost controller to do that. Ok now we have plenty of wastegate room to work with so scenario 1 wont be a problem. What would happen? Obviously the TINY exhaust side of the stock subie turbo would be a huge bottleneck for 8.0L of exhaust gas. So we'd want to run 20 psi but we wouldnt reach that number most likely. WHY? because there would be so much backpressure in the headers from the exhaust not being able to squeeze through the subie turbo so well over 3 psi of pressure would build up inside the headers/exhaust manifolds. That would thus force the wastegates open and 20 psi wouldnt never be achieved. This is why people with 7 psi springs cant run 35 psi without their gate opening up. I've seen people pull the vacuum hose off the wastegate completely and the car might only run 24 psi because there is 7 psi of exhaust pressure inside the exhaust manifold when there is 24 psi of pressure inside the engine.

if anyone has any questions please feel free to ask as I'll do my best to explain. There are other things that can sometimes effect boost control such as recirculating, backpressure in the wastegate, backpressure in the exhaust system, etc... but if anyone wants to know about that, just post it. Thanks and enjoy the info guys!!!

Also check this video out aswell, great video describing wastegates-- http://www.youtube.com/watch?v=PA5T5PnWE-k

Courtesy of Joeeveryman87

Info from "ScKcBc's"

[joeeveryman87]

Just some more random information as i learn it all better i figured id post my findings on the thread......soooooo

Blow off valves are air pressure release valves that can be mounted on the intake piping of a turbocharged car anywhere in between the turbo and the throttle body. They are also known as dump valves, or vent valves. The blow off valve pictured below is made by Greddy and is the Type-S model.



A blow off valve has few purposes, but is still a very important piece.....

The functions of a blow off valve
Without a blow off valve, when you let off of the gas, the compressed air in your intake piping increases to great pressures as the turbines in the turbocharger are forced to a screeching hault. The extreme pressure forces the air back through the turbocharger, increasing the wear on the turbo.

With a blow off valve, when you let off of the gas the air pressure left in your intake piping is relieved as the blow off valve opens up. This allows your turbo to continue spinning in the proper direction, preventing damage to the turbo and allowing for a faster return to positive air pressure in the intake piping.

How it works
A small diameter hose runs from the intake manifold to the blow off valve. When the pressure in the intake manifold is positive (in boost), the pressure in the small hose keeps the wastegate closed.

Once you let off of the gas, the throttle plate closes, and all of the air in the intake manifold is sucked into the engine. With negative, or zero pressure in the intake manifold, the blow off valve opens up and releases all of the compressed air from the intake piping.

[joeeveryman87]

Hopefully by the time i get back from my deployment this thread, all my research and all the input from all you, will pay off greatly since i plan to do the "install" myself

[joeeveryman87]

No better info than from Garret Turbo themself!!

A/R (Area/Radius) describes a geometric characteristic of all compressor and turbine housings. Technically, it is defined as:

the inlet (or, for compressor housings, the discharge) cross-sectional area divided by the radius from the turbo centerline to the centroid of that area (see Figure).



The A/R parameter has different effects on the compressor and turbine performance, as outlined below.

Compressor A/R - Compressor performance is comparatively insensitive to changes in A/R. Larger A/R housings are sometimes used to optimize performance of low boost applications, and smaller A/R are used for high boost applications. However, as this influence of A/R on compressor performance is minor, there are not A/R options available for compressor housings.

Turbine A/R - Turbine performance is greatly affected by changing the A/R of the housing, as it is used to adjust the flow capacity of the turbine. Using a smaller A/R will increase the exhaust gas velocity into the turbine wheel. This provides increased turbine power at lower engine speeds, resulting in a quicker boost rise. However, a small A/R also causes the flow to enter the wheel more tangentially, which reduces the ultimate flow capacity of the turbine wheel. This will tend to increase exhaust backpressure and hence reduce the engine's ability to "breathe" effectively at high RPM, adversely affecting peak engine power.

Conversely, using a larger A/R will lower exhaust gas velocity, and delay boost rise. The flow in a larger A/R housing enters the wheel in a more radial fashion, increasing the wheel's effective flow capacity, resulting in lower backpressure and better power at higher engine speeds.

When deciding between A/R options, be realistic with the intended vehicle use and use the A/R to bias the performance toward the desired powerband characteristic.

Here's a simplistic look at comparing turbine housing geometry with different applications. By comparing different turbine housing A/R, it is often possible to determine the intended use of the system.

Imagine two 3.5L engines both using GT30R turbochargers. The only difference between the two engines is a different turbine housing A/R; otherwise the two engines are identical:
1. Engine #1 has turbine housing with an A/R of 0.63
2. Engine #2 has a turbine housing with an A/R of 1.06.

What can we infer about the intended use and the turbocharger matching for each engine?

Engine#1: This engine is using a smaller A/R turbine housing (0.63) thus biased more towards low-end torque and optimal boost response. Many would describe this as being more "fun" to drive on the street, as normal daily driving habits tend to favor transient response. However, at higher engine speeds, this smaller A/R housing will result in high backpressure, which can result in a loss of top end power. This type of engine performance is desirable for street applications where the low speed boost response and transient conditions are more important than top end power.

Engine #2: This engine is using a larger A/R turbine housing (1.06) and is biased towards peak horsepower, while sacrificing transient response and torque at very low engine speeds. The larger A/R turbine housing will continue to minimize backpressure at high rpm, to the benefit of engine peak power. On the other hand, this will also raise the engine speed at which the turbo can provide boost, increasing time to boost. The performance of Engine #2 is more desirable for racing applications than Engine #1 since Engine #2 will be operating at high engine speeds most of the time.