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Discussion Starter #21
Not quite sure on the fuel pump as I did not fit it, JM Imports fitted it when they imported it for me.

Car is an R34 & was expecting 500ish bhp on that spec.
 

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Er, according to whom mate? :(
Never trust a brochure or sales-person (private or professional) when it comes to how much power something has.

Step one for me would be to request the invoice for the new fuel pump so you can see what's in it. If they've used a second hand pump (or worse, a brand new pump that doesn't have sufficient capacity) then you could end up tearing holes in things.

From there, take it to a reputable tuner and get them to retune it.
It could be the petrol you're using, it could be a wiring fault, it could be fueling, timing or many many other mechanical faults.
The tune should allow you to pinpoint the problem, potentially fixing it or at least steering you in the right direction with a better diagnosis.

Without knowing more about the car (previous work and modifications, current ECU, fuel type, cams, turbos................) there's very little anyone here would be able to suggest accurately.

Remember, talking to strangers on the webbernet will only get you so far - at some point you'll need to pay someone to look at the problem (unless you have the know-how yourself but if you're asking questions on the boards then i'd hazard a guess that you're mechanically inept like me!!! :) )
Even the most gifted mechanic, engineer or industry professional could struggle to identify the issue without seeing it first hand so getting it into someone is generally a good idea to do with any fuel injected performance car - a retune early on will mean that it's running on the right gas, at safe power levels until you figure out what direction to take the build.

Hope this helps mate, keep me posted!
 

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Also, from your original post:

The mapper was unable to add any more ignition advance in order to make power as it had started to knock & pulled he the timing back again.
Then later:
The cam pulleys haven't been adjusted yet as I am planning on doing this once running correctly and then make adjustments, carry out a dyno pull and see what effect it has on response etc.
Not knowing tuners in the UK but most in NZ start from a TDC tune, then use the wheels to provide fine adjustment for most or larger adjustment for those requiring torque at certain points of their rev range (retarded timing for down low punch like a rally car or more advance for higher top end for highway rolling).

Again, I'm not a mechanic, but these two points seem quite opposed to each-other.

Really sounds like you need to find someone else to work on the beastie mate.
 

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Discussion Starter #24
Totally understand that every car is different & will have varying results but going by the masses that have these turbo's and other similar spec is where I have built my expectation on output from!

I'll pull the fuel pump at some point over the winter & run thicker cables while I am at it.

Current tune is safe for lower grade fuel (95) as we adjusted the ignition timing to suit when unable to add any more advance.

It is maybe my terminology that I have used but the ignition timing/advance we were adding during the mapping is the adjustment of the timing of spark & this was when were not able to advance it anymore & det was detected. The cam timing only relates to valve lift timing, the Tomei Poncams cam positions are slightly different to standard cams I believe & have already some advance/retard built into them, this was why I wanted to map the car with the vernier pulleys at 0, once I had a satisfactory tune I would then play with the cam timing to move the power curve.

Yea your right, although the forums can & have been very helpful with ideas of potential issues, hence my post, it is giving me plenty of varying options/ideas of what to check or what it may be & I will be working through them over the winter. Just a bummer that the weather is pants now so the car is tucked up for the winter, I will be taking it back onto the dyno after the roads clear up!
 

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You know it's an AWD right? Rain and snow shouldn't be too much of a problem! :p

Nah, I hear you, do what ya can when you can.
To me, what you've said about the tuner makes me think you need someone a bit more switched on to have a look mate - they would have told you not to run 95 octane for a start!
98 Octane burns a bit cooler so is better for a boosted engine. If you don't have a gas-station in your area that sells the good stuff then you'll need to de-tune the vehicle and manage your expectations about end power figures. ;)

I'd love to recommend a tuner in the UK for you but being on the other side of the world can be annoying sometimes! Sorry mate!

Good luck though - hoping it all goes ok!
 

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Discussion Starter #26
Haha yea, the snow isn't the problem, its the salt spread on the roads = rusty Nissan!

Its run on 99 octane fuel but when we started having issues the map was adjusted & timing retarded to keep it safe, it wasn't actually mapped or run on 95 octane fuel, I do have a second map on the link with retarded timing & low boost that will allow lower grade fuel to be used if stuck - the rationale for this was future proofing if I take a run over to the West Coast etc where there is no option for higher grade fuel.
 

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I***8217;ve used BkR8EIX for years. No problems. I***8217;d change from 7s to 8s.
I’ve used them too but when coil springs are not as they once where could potentially cause misfire issues. Easy fix is stretch the springs a little. Best option buy the correct JIS plug.
 
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