SPOautos

You mind me asking what timing you were running at peak tq and also was it on pump gas? Sorry if you already mentioned the fuel type I missed it

Awsome numbers btw !!!!

STEPHEN

artguy

yeah...the timing question...that would be very interesting to see....good job stephen.

Im still tripping on these numbers...Im genuinely impressed.


good luck to you matt. dont believe me...call the turbo builders and ask them about high boost through the hitatchi or stock cartriges. ...or run them for six months and when they dump oil all over your driveway you can pull them apart and see how many chips of fan were spewed out your exhaust or into your IC.



j

matty

oh may god..so graphic...gruesome.
so u think 15 psi is too much ?

RX794

I was there, and I know everything done to Boostn7's car, he's being honest about what's done to the car, he's not hiding any secrets, or anything like that, the dyno that he used was a dynojet. I'm pretty sure Boostn7 will answer your questions as soon as he sees the post. As far as your question about the stock power trailing off at 6k and not 7k rpms, you can see it in the torque curve, take a look at it.

SPOautos

Man if your turbine wheels were eat up it sounds like a piece of apex seal went thru them at some point....or they were not balanced good and hit the housing....if they were 6 months old and you didnt blow your engine I'd probably go with the later.

STEPHEN

kwikrx7

I ran 14 psi for 2 years (seq for year/non-seq for year) - took the turbos off and they had a small leak but between oil changes (2K miles) my oil was always full. The turbos looked pretty good for running high boost. Although I wasn't running 17-18 psi - that's alot for those little Hitachis. I'm glad to see some sets holding up.

zayrx7

Anyone that thinks that is a good setup is wrong. Dont copy it, unless you want to fry your turbos after a couple of weeks. At that boost your are on the edge of blowing things up.
Impressive HP for what it is.

Jodeny

iTrader: (3)

You are the third guy that has stated this without any proof. I ran 17-19 lbs for three years and my turbos are fine. They start to lose efficiency around 18 pounds and by 20 you can feel that they just arent moving enough air. There actually was only a five hp difference between 19 and 20 pounds on my car.
John

Jodeny

iTrader: (3)

John D- were you running pump gas??

Marshall

Joden, the lack of evidence supporting this is interesting. I once questioned the 15 psi max theory by asking if people with large street ports should run 12 psi instead since the turbos are working just as hard as a 15 psi stock port. (IE moving enough cfm to generate 12 psi on a street power would be the same as 14-16 psi on a stock port) ...silence. Now Anthony comes on and says his intake temps were fine at 18 psi. So much for the efficiency argument (granted there are MORE efficient compressors out there, BNR for example). Anyways, in reality, I think you've got a few people that had bad luck with a set (mostly from apex seal debris and improper rebuilds) and make them look worse than they really are.

Jodeny

iTrader: (3)

........ahhhh, a reasonable man with a mind that thinks for itself. That is refreshing on this forum. I tried sharing my combination two years ago but I was incessantly flamed by 15 year olds that seemed to think they were mechanical engineers. At that moment I realized it just wasn't worth it.
by the way my trap speed were 122mph in 55 degree temps at 18 psi so. It seems to me since John D mph'd higher that his tuning is better than my homemade halfway racemap.

John

matty

i know several people that run 15 psi for years with no problems..
I will admit though that doubling the stock psi to 20 makes me alittle warry but i cant see whats wrong with running 14-16 psi as many people do it with no problems. The reason 20 makes me warry is b/c i havent seen many people do it....thats all. I havent seen any data either way.

The thing i havent figured out is why do some FD's make 320 rwhp with all the bolt ons versus others with the same setup that make over 350!?! In addition boostn7 comes on here reporting 402 rwhp (on stock motor), has 11 second time slips with amazing mph, and has tons of people who respect his word...I dont doubt you in the slightest bit...just help me to understand why does such a large deviation exist?
My car has 30 k miles and i have all the bolt ons...if i dyno below 350 rwhp i am going to feel cheated. Dave at KD will do the tuning in april for 15 psi.

Boostn7

For those which are genuinely impressed
==> BIG THANKS

All runs were made on pump gas...Sunoco 94

Artguy: i think XS Eng will tune with a high safe margin in mind...... plenty of fuel and conservative timing.

-Twins are set up non-seq the proper way and everything ported matched in the manifiolds...

-Motor is stock(unless Mazda ported it !!!!)...tunning has something to do with it making power to ~7krpm.

-The twins may be getting out of their range....but intake temps did not reflect that......from 3k to 7k on a 4th gear pull it actually dropped 4°C !!!!....big fan may have helped and of course Greddy 3row.

>>Id be curious to see if you could duplicate those numbers on a different dyno. (the bnr set dynoed 460rwhp at one point and they dynoed on a different dyno and pulled 412)<<

Dyno was a dynojet...so i assume if I jump on another dynojet it should be close or higher if I get the 1200cc in the motor.
As far as the 460rwh !!!! well, subtract ~15% and that's exactly Steph's actual rwh !!!! (different dyno)
and only after a 3rd dyno visit (dynojet) did he menaged over 400rwh.....412rwh...which I was very impressed.....it shows power verywhere.
Either way I believe he's making more hp based on his 125mph.
Bryan is doing a hell of job with those twins...many other companies have failed in upgrading them in the past. Hmmmm...w/ a set of BNR's in my car I may even start more trouble.
I don't expect everyone to go and crank up the boost on their stock twins because I'm doint it.
I've been tunning the car for awhile and to be honest...it's been running over 14psi for over 6 months.

Combination, tunning and luck !!!

Jodeny

iTrader: (3)

Who got to you?? Are you on payroll?? HAHA just kidding. I would think that the BnR would make a little more power than the stockers but the exhaust is where the true restriction is. I would like to see what I could get out of a set of them though.
John

AnthonyNYC

iTrader: (3)

John,

It's called the "parrot effect".

One guys spits something out and the other guy just goes around and repeats it over and over, kinda like a parrot.



Anthony

kwikrx7

I've asked this before a while ago and got many answers (probably by 12 year old mechanical engineers ) but I plan on running my BNR hybrids sequentially at 16 psi on the street. Obviously they have a more efficient compressor wheel and internals but how do think they will last long running sequential? I see most guys running the ultra high boost on stockers (16-19 psi) running parallel but only a few running 16+ psi in sequential form. You guys seem to be the "proof" experts as far as high psi on the Hitachis what do you think - parallel or sequential at high boost? I prefer sequential....

Boostn7

>>Who got to you?? Are you on payroll?? HAHA just kidding. I would think that the BnR would make a little more power than the stockers but the exhaust is where the true restriction is. I would like to see what I could get out of a set of them though.
John<<

Payroll !!!! that reminds me.....Bryan, where's my money?
NO...just kiddin.... I've known Bryan for a little awhile.....
we have been talking about his upgraded twins for some time now.........I keep telling him...." I think the stockers have a little left in them".....and he laughs at me all the time.

When running anything over 15-16psi non-seq is the way to go....I will never go back.....simply less headaches.
Obviously Chuck, seems to be another exception..with seq-twins.

Later,
John

rx7tt95

Kwik,
I ran 14psi (only! ha) sequentially for about 58K miles. When I pulled them off to replace with a large single, the primary looked used, spewing a bit of oil, but the secondary looked brand new. Just my experience. On the street, city driving, it seems the primary sees twice the amount of usage. Then again, could be my driving style. :-)
Michel
95RX7

artguy

well said rx7tt....

my proof came when I opened up the turbos and saw what the heat was doing to them...the wheels were very very brittle. you could see how the heat had started to blow by and slightly bend the wheels. eventually this caused pieces to chip off and head out the exhaust and into the IC. I replaced my motor due to a side seal problem later and found no damage to my apex seals. the chipping was from heat.

that was all the proof I needed. from the outside they looked like any other leaky set of turbos...open them up and find your data yourself parrotboys.


hahah

j


kidding

Jodeny

iTrader: (3)

I have had mine on and off numerous times, they always mike up fine. The only time I ever had a problem was at 6k miles- my air box tabs broke(unbelievable-huh?...mazda 'quality') and the primary compressor and bearing were wiped out due to unfiltered air .

John

AnthonyNYC

iTrader: (3)

As far as chipping exhaust wheels etc... I understand where guys are coming from and I agree it is from heat. BUT it is not heat from running high boost. It is heat from running LEAN. High EGTS will destroy anything.

Let's say you have driver 1 that runs 14psi. He has stock injectors, never tested his car with a wide band, constantly running the car lean, his exhaust turbines are chipping. I expect that.

Let's say you have driver 2 that runs 18psi and drags his car daily. He has upgraded injectors, FPR, has an EGT gauge to compare temps. He has been on numerous dyno runs and runs his car with a wide band making sure he is not running lean. I do not expect that turbo to have chipping issues etc.

I think you can run high boost but you have to make sure you are not running lean. Jodeny, John D, these guys make sure they have enough fuel etc...John was on the dyno for god knows how many passes and he DOES NOT drive "easy".

One more thing, I have seen many single turbos damaged prematurely from running cars too lean for extended periods.....

...If anyone is saying the compressor turbines are the one that was subjected to high heat, what temps are you referring to? How how in degrees were your intake temps? The reason I am asking is because for a short time I had the twins and haltech. I beat on the car an various ambient temps to compare. There was no noticeable diff in air temps between 14psi and 18psi.

Just my 2 cents.....

Anthony

rxrotary2_7

very well said.

karken29

treceb

awesome...
how come i dont see any FDs in union county. could it be the season???

forcefed1

Where is this idea the stock twins loose efficiency at some boost level coming from? the only real way to find out in my book is to get the intake temps. The only way to do that is to use a thermocouple at the compressor outlet then run various boost levels... Come on guys lets get a bit more fact in this thread or hell on this forum. as anthonyNYC stated teh heat from running lean is far far higher than anything your compressor will generate from a 4 PSi increase.

so who's up for the TC test? you can forget about the stock sensor.

Greg