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Discussion Starter #1
Can any of you help me please.
I have had a few people advise me that my rev limiter has been set to high on my car.
The maximum recorded on my power diagnostic is 8520rpm
It has been running like this for just over 3 weeks and now after noticing smoke pouring out the back of the car i have had the engine pressure tested and it is leaking on cylinder 1.
The reason it was set this high is because i made the mistake of buying the HKS GTRS turbos and because of their large size, maximum power is not acheived untill 8330rpm.
After fitting all my parts (just three weeks ago) i had smoking problems just before the car was mapped and it was narrowed down to oil seals on the turbos( the engine was pressure tested and it was completely fine).
Turbos were sent off, repaired, then refitted and the car was mapped.
My car has standard pistons, and engine is completly stock.
Advise, coments greatly appreciated.
 

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why did a tuner fit gtrs to your stock engine without giving you due warning. Or did he, and you just chose to ignore.

Bummer about your car mate. As all the RB's are quite similar I would be inclined to say 7000 ish revs is the max you would really want to rev it to.

Many people say its revs and bad mapping that kill engines as apposed to high boost
 

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if you really want to use the 8500 ceiling of the GTRSs then you need to work on the internals too.
on stock internals 7500 is the 'safe' limit really....
(IMO of course)
 

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Discussion Starter #7
gtr mart said:
why did a tuner fit gtrs to your stock engine without giving you due warning. Or did he, and you just chose to ignore.

Bummer about your car mate. As all the RB's are quite similar I would be inclined to say 7000 ish revs is the max you would really want to rev it to.

Many people say its revs and bad mapping that kill engines as apposed to high boost
i bought the hks gtrs turbos brand new off of someone on here and did'nt look into them before i bought them.... wish i had now!!!!!!
my tuner said not to worry as they could map alot of the turbo shuffle out.
i know they have done their best but the shuffle is a massive issue, not only to the drive of the car but also fuel consumption... i do about 30miles to £20 its an absolute joke.
i am having some new smaller garrett turbos fitted to sort the car out and also hopefully save a fortune on fuel. i recon im putting around £150+ a week in it!!!!!!!!!!!! its either the fuel consumption gets better or i fix it and sell it.

ive also been advised that with these new garrett turbos( im not sure exactly what ones they are) my max power will be alot lower down the rpm so i should crack the 600bhp mark.
apparently another car with the same sort of set up made 550bhp with 1.2bar boost, so running mine on 1.4bar should see over 600bhp.:clap:
 

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what turbos are they. Make sure you find out or you will easily find yourself in this situation again and I bet its you that hvaing to pay for this work to be sorted.

GTSS would have been more appropriate - certainly for 550 / 600 bhp and Im sure it would have driven very nicely.
 

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Discussion Starter #9
gtr mart said:
what turbos are they. Make sure you find out or you will easily find yourself in this situation again and I bet its you that hvaing to pay for this work to be sorted.

GTSS would have been more appropriate - certainly for 550 / 600 bhp and Im sure it would have driven very nicely.
the garrett turbos are apparently rated at around 330bhp each and come highly reccomended by my tuner. i was gonna go for the trust t157z. they are £1450 delivered from nengun, but i can get these garrett ones for the same price next day delivery with a years guarantee.
i thought the hks gtss were quite smallish turbos good for around 500bhp????
 

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Also if you wanna go that high, internals such as the bottom end are not your only concern. The head needs to be addressed to me more than the bottom end in this higher revving problem. Things like the Valves, valve springs & retainers need to be upgraded to avoid valve float while revving so high. IMO
 

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8500rpm is a fairly serious rev limit, on a standard bottom end I wouldnt even think about it!

Mine's fully balanced with ARP rod bolts so Im happy revving it to 8000rpm to keep my T04R spooled up, although Id much prefer a setup like my old N1s where they'd spool by 4000rpm and you could change at 7500 and they'd still be on song when you took the next gear :)
 

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7800 is about the sensible limit for repeat application with something like GT-RS turbos, an occasional blimp to 8000 would likely be acceptable, but not recommended. The point of peak power can be tuned with the cam-timing, so if it were setup correctly taking the standard bottom-end into consideration it would give peak power in a place that is acceptable for the other components (ie. 7200-7400ish), though at the expense of producing the most possible power from the turbos - a small price to pay if it means your car lasts more than a week.

Of course if your tuner uses the road to tune, its an exercise in time-wasting trying to set the cams without some way to quantify and prove what is a good or bad movement of inlet or exhaust cam.

Just my 0.02p worth before I head to bed. :p
 

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drive said:
Can any of you help me please.
I have had a few people advise me that my rev limiter has been set to high on my car.
The maximum recorded on my power diagnostic is 8520rpm
It has been running like this for just over 3 weeks and now after noticing smoke pouring out the back of the car i have had the engine pressure tested and it is leaking on cylinder 1.
The reason it was set this high is because i made the mistake of buying the HKS GTRS turbos and because of their large size, maximum power is not acheived untill 8330rpm.
After fitting all my parts (just three weeks ago) i had smoking problems just before the car was mapped and it was narrowed down to oil seals on the turbos( the engine was pressure tested and it was completely fine).
Turbos were sent off, repaired, then refitted and the car was mapped.
My car has standard pistons, and engine is completly stock.
Advise, coments greatly appreciated.
Who is your tuner mate?
 

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gtr mart said:
Many people say its revs and bad mapping that kill engines as apposed to high boost
Agreed. Inertial loading on conrods is far higher than power loading.


As a reference drive. The stock redline is 8000rpm and the rev limit is 8200rpm. In a way the over-reading R32 rev-counter is a good thing. 8000rpm = 7500rpm on mine and that's as far as it ever goes.
 

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My peak power is 6900rpm, so the rev limiter on the PFC is set at 7250rpm. There's no need to rev anymore on my set up....

BTW, i have standard internals (as far as i'm aware)
 

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Discussion Starter #16
m6beg said:
Who is your tuner mate?
rising sun in Alton Hampshire. they have said when my new turbos are fitted they will lower the rev limit down to 8200
 

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drive said:
rising sun in Alton Hampshire. they have said when my new turbos are fitted they will lower the rev limit down to 8200
You need it lower than that mate. That is very high for a standard bottom end.
For safety i would go around the 7700 mark max.

That's me anyway.

Mick
 

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Discussion Starter #19
m6beg said:
You need it lower than that mate. That is very high for a standard bottom end.
For safety i would go around the 7700 mark max.

That's me anyway.

Mick
cheers mick, ill tell them to set it no higher than 7700, the last thing i want is a broken car AGAIN!!!!!!!!!!!!!!!!!!!!!:puke:
 

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Check out my 0-300 km/h video's on Kismo.dk I ran the stock block to 8500 for 10xxx miles and the last 2xxx miles op to 9000 rpm with 1,8 bar boost from my T88.

Just dont engine brake over 7500 too much (let of the throtle suddenly and putting the braking load on the engine)

There is two weak point in the stock block, conrod bolts during engine braking and the stock oil pump looses presure above some 82-300 rpm.

With good oil ( Castrol 10/60 TWS) often changes and sensible oil temps (80-100 degress C) you can run 8000 easy easy easy.8500 easy easy, 9000 be carefull.

When I rebuilt the engine after 12-13000 miles of varied driving and alot of testing the main and big ends were SHOT but no damage to either components, just very worn.

Good luck,
 
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