cpdevo31

boost gauge is fine. also when i was at buschur racing to get tuned by Al, my car had a flat line of 21psi, give or take .3 at the most, from 3800rpms to 7200rpms.

on coolnights my boost hits around 22-23 and holds there as well.

EVOlutionary

iTrader: (38)

Doubtful. If someone isn't "hardcore" evough to run AI or race gas when they hit the track, I doubt they are going to be screaming around town at 8500 rpms every day on the stock block.

Also I think most would rather have a 3500 - 8000 rpm power band (4500rpm spread) than a 5000-8500 (3500 rpm spread) for a daily driver.

EVOlutionary

MalibuJack

iTrader: (5)

I happen to agree.. However there's something I"ve discovered in doing my research with different turbos.. and what led me to making some decisions I made over time. I've tested 6 different turbos on different cars, 4 of them stock based, and one big tubo kit, the lag on a turbo is not the only factor, but the power it produces.. Your peak torque will be where the turbo hits full boost, but I looked at over 100 different dyno charts for different turbos, and even though a big turbo is not in its peak boost, its producing roughly similar numbers under that curve UNTIL it hits peak boost, then things change. I'm not really talking about a big torque hump at low RPM that stock type turbos can do, but an area under the curve where you feel this in daily driving.

If you go from a mildly tuned stock turbo car, to a GT35r, you'd likely not notice enough of a difference for it to be a problem.. THIS IS WHY many people say the GT35r isn't so bad, their making an improvement over stock regardless..

In my case, I'd be going from a car that produces almost 400wtq at 3800rpm, to about the same number at 4000rpm at lower boost levels.. Plus the fact that its on pump gas.

You just can't beat the stock turbo good numbers and low-end power, just do your research and compare things from a level YOU ARE CURRENTLY AT.. I'm sure someone going from a 20G-9-5 to a GT35r (or even a 50 trim) would notice a significant difference in midrange, but its not as bad as I thought it might.. If your going from a stock turbo, with mild mods, then you might not notice any difference in drivability.

To each his own I suppose.. My real point is look at the difference from the Point your already at, and where you want to go. Its just very hard to quantify this without driving cars that have the mods you want, but I can tell you that any improved stock turbo is a BLAST to drive around town, and that wider powerband really makes driving around alot easier because downshifts aren't necessary as often. Some people upshift and downshift all the time regardless, and those people may not find the additional lag of a big turbo an annoyance at all..

BUT you can talk about this topic all day long, and everyone has their needs and opinions, and you can discuss this all you want. But asking the same questions and getting the same info over and over again is becoming counterproductive and will only delay your decisions.

Its a cut and dry decision..

If you Like low-end torque, drive at low speeds and lower RPM's, likes to feel like there's always power there, stick with a stock based turbo and you'll be damn happy.. Anything bigger really only adds to bragging rites and broken parts (Lets just say that I'm going against my advice on some of this, but my needs are different)

Also, tune has a huge impact on the quality of your drivability and that makes a HUGE difference on what you percieve as lag....

Ted B

iTrader: (6)

Wow, double the money invested, less spool, and the same peak power with less torque. Excellent logic!

Spooldyou

iTrader: (52)

OK I just spent an hour reading back from page 52, What the major diff between the 5 blade and 6blade? Sorry for the newbish question.



Whats the New turbo your talking about? 3065?

Ted B

iTrader: (6)

The major difference is they have different compressors and behave differently.

The 6-blade appears to suffer from a configuration mismatch that causes a pressure ratio problem at high boost. I made more torque and the same power with a TME, and I would have been better off sticking with my TME.

The 5-blade does not have this problem, and appears to be a much better design. It costs more, but offers more potential.

lwpz

Dear David,

At the end of 2006, I purchased a BR-20G-5 (not LT) turbo through a dealer locally and recently got it installed and tuned (I know I delayed it quite a bit)

During the tune and while driving, I encountered a slight compressor surge at part throttle (~24psi boost), as I was trying to maintain a cruising speed (without the need to go full throttle).

The compressor surge is quite audible, but the car does not seem to buck and jerk (as described in your post in 2005).

Mostly, I have had the car on a circuit and it seems quite fine to me. However, I do encounter some problem when I'm increasing my throttle out of a corner. It surges for a moment and down the straight I'm already on full throttle. There's another circuit, which requires more "moderation" of the throttle, which I'm worried about.

I was wondering if there is anything I will be able to to do solve this problem.

The BR-20G-5 has sold quite a number locally, but I'm not sure if you have had any e-mails or contact with respect to this issue?

Appreciate your feedback and if you could provide me your e-mail, I will send you a video clip of the part throttle surge if you are interested.

Thanks.

Pin

David Buschur

iTrader: (53)

There is nothing you can do to eliminate the surge on the 20g-9-5. You can upgrade it for a reasonable cost to the LT which has less surge but I still won't say it is 100% surge free under every single situation.

cfdfireman1

iTrader: (11)

lwpz'

The post you quoted was about the 20G-8 not the turbo you have. How much for the upgrade to the LT and how long is the wait David?

EVOlutionary

iTrader: (38)

I agree with the above statement. You can get it to surge with improperly matched parts, but with proper supporting mods it can be 100% surge free.

One setup I know for a fact that will not surge with the EvoGreen/20GLT is stock ECU and stock EVO9 (JDM MR) BOV recirculating. One downside is this BOV may not hold as high of boost as the EvoGreen is capable of on race gas. . .

LWPZ -- What cams, BOV, and ECU are you running with the 20G9-5 that is surging?? I would recommend having the turbo upgraded to the EvoGreen specs -- you will gain more top end power without really losing any low end.

EVOlutionary

paymon

Can the surge eventually kill the compressor wheel?

David Buschur

iTrader: (53)

I have never seen a compressor wheel fail from surging.

I spoke with FP today actually and am HOPING that by next Friday all the Greens/LT's we have outstanding right now will be in and off of back order.

yellowEVO21

iTrader: (24)

David, will there be any extras for new orders or is that just wishful thinking?

David Buschur

iTrader: (53)

Right now my main goal is to ship the orders we have, which are QUITE a few turbos. I may end up with an extra one or two depending on what they ship us.

lwpz

Hi David, thank you for the reply. Do you mind PM-ing the cost for the upgrade?