Car Breaking down High revs

[chook]

The old SS doesn't appear to be performing as good lately. Car is missing at high revs but can't exactly put my finger on when it started. Car has a Mafless tune from Sam and has run faultless for close on 3 years.
Where should I start looking at
Replace Plugs, Leads maybe a crappy tank of BP Ultimate.

Perhaps a return trip to Sam??

If I have to what plugs and leads ??

[TommyVTss]

the standard plugs and leads are the best you can use....

[Sonnymad]

The old SS doesn't appear to be performing as good lately. Car is missing at high revs but can't exactly put my finger on when it started. Car has a Mafless tune from Sam and has run faultless for close on 3 years.
Where should I start looking at
Replace Plugs, Leads maybe a crappy tank of BP Ultimate.

Perhaps a return trip to Sam??

If I have to what plugs and leads ??

You will find it may be the leads ,how many km's have you done ?

regards sonny

[chook]

KMs is now on 94 K's so what leads would you suggest sonny ? Time to replace?

[vxssgurl]

The old SS doesn't appear to be performing as good lately. Car is missing at high revs but can't exactly put my finger on when it started. Car has a Mafless tune from Sam and has run faultless for close on 3 years.
Where should I start looking at
Replace Plugs, Leads maybe a crappy tank of BP Ultimate.

Perhaps a return trip to Sam??

If I have to what plugs and leads ??

Is it actually missing or is it hunting for fuel (ie mini surges) at WOT?

Missing is one issue - hunting for fuel is another.

Plugs do foul if you use crap fuel - the heads also eventually burn out with time, leading to sluggishness...

Leads get old and develop Altzheimer's...

Fule filters clog, meaning not enough fuel getting through, which you don't really notice until you induce WOT...

Injectors foul, also resulting innot enough fuel...

Crap fuel contains water and/or too great a % of ethanol, also resulting in not enough go juice being available under the pedal - but water in fuel will foul your system thoroughly and immediately - doesn't induce sluggishness at WOT...

Could also be your fuel pump is beginning to fail, which, as in all the other cases, results in not enough fuel being injected at WOT...

If it's hunting for fuel and not missing (because really, if it's got a miss, it will be there all the time - cause timing is timing, doesn't matter what position the throttle is in) - my immediate suggestion is to stick some injector cleaner in her, then fill up with absolute primo fuel - like the new Shell V Racing.

After that, as long as it's not your FP, change her leads, plugs and filter.

Still no better?

Get ye back to Sam.

[chook]

No not hunting just breaking down, might check the plugs on Weekend and maybe look at a set of leads, any suggestions on brand or should I stick with factory?

[ssgirl2]

KMs is now on 94 K's so what leads would you suggest sonny ? Time to replace?

Did you replace the spark plugs at 80,000kms? If not, I would be replacing the plugs and leads with genuine Holden parts ;) and go from there.

SS :driving:

[vxssgurl]

No not hunting just breaking down, might check the plugs on Weekend and maybe look at a set of leads, any suggestions on brand or should I stick with factory?

If it's a genuine miss, I would be heading straight back to Sam to diagnose what (exactly) is causing it - cause like I said, it's going to be there all the time - whether you notice it or not, cause electronic timing can't advance or retard itself at WOT like your traditional (read - old!) carburetted set-ups sometimes did/do.

Could be something simple - or not. When your baby's health is at stake, don't risk it... listening (and acting) on our hypotheses could cause more trouble... (even though we all mean well!)

Let us know the outcome, yeah?

[Sonnymad]

KMs is now on 94 K's so what leads would you suggest sonny ? Time to replace?

If you have never changed the leads for those km's,defantly change them as they should be changed every 50k,go to the dealer and get a genuine set,make sure they are the red set not the black,fit them on and i,m pretty sure ur miss will go away :)

regards sonny

[vx_clubby]

I got a similar problem, I got a new exhaust, and they changed the leads to topgun 10mm, and since then its seems to back fire sometimes when you accelerate, would this be the plugs?
or maybe needs a retune after exhaust?
the car has done 40000kms

[Sonnymad]

I got a similar problem, I got a new exhaust, and they changed the leads to topgun 10mm, and since then its seems to back fire sometimes when you accelerate, would this be the plugs?
or maybe needs a retune after exhaust?
the car has done 40000kms

We have used those topguns before they play up,its best to get the genuine leads,the "red" ones,they are of real good quality

regards sonny

[chook]

Thanks guys will try some new leads.

Rang around a few dealers who had varying stories. One dealer advised that they did not come in a set and were sold individually and they were $48.00 each WTF. I argued the point and told him that was crap (Thanks Sonny) and his response was oh Sorry. set $176.00. That's over $200.00 difference.
Got to watch these bloody dealers.

[vx_clubby]

We have used those topguns before they play up,its best to get the genuine leads,the "red" ones,they are of real good quality

regards sonny

OK cheers, I will go with your advice, Im not sure what it could be otherwise, the standard ones have been ok since I had it, so I might go back to genuine :)
thanks

[Mozz]

Is it actually missing or is it hunting for fuel (ie mini surges) at WOT?

Missing is one issue - hunting for fuel is another.

Plugs do foul if you use crap fuel - the heads also eventually burn out with time, leading to sluggishness...

Leads get old and develop Altzheimer's...

Fule filters clog, meaning not enough fuel getting through, which you don't really notice until you induce WOT...

Injectors foul, also resulting innot enough fuel...

Crap fuel contains water and/or too great a % of ethanol, also resulting in not enough go juice being available under the pedal - but water in fuel will foul your system thoroughly and immediately - doesn't induce sluggishness at WOT...

Could also be your fuel pump is beginning to fail, which, as in all the other cases, results in not enough fuel being injected at WOT...

If it's hunting for fuel and not missing (because really, if it's got a miss, it will be there all the time - cause timing is timing, doesn't matter what position the throttle is in) - my immediate suggestion is to stick some injector cleaner in her, then fill up with absolute primo fuel - like the new Shell V Racing.

After that, as long as it's not your FP, change her leads, plugs and filter.

Still no better?

Get ye back to Sam.


That's a good summary of the potential things to look for/ look after when owning an LS1 type vehicle - the only other thing I would add is valve float at high revs due to the need to put a decent set of valve springs in :)