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I am just wondering.

Does using the Bee-R Rev Limiter for fun (just to throw flame to make sure the tailgater back off) cause any damage?

I am just not 100% sure that throwing extra fuel that ignite in the turbo housing will cause no damage at all. Gasket? Will anything in the engine wear?
 

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there's a guy on the SXOC who lost his engine due to bouncing off the limiter on the Bee-R. Bouncing off the limiter basically caused the upper valve assembly to go walkabout, cam jammed, timing chain snapped, goodnight sweetheart so to speak :(

i absolutely hate these limiters, they're totally pikey imo, and yes (also imo) they place monumental amount of strain on the turbo gaskets.
I'm expecting to see a lot of cars develop problems with prolonged use of them. I'm sure there'll be those that disagree, but it's my opinion and i'm sticking to it until i'm convinced otherwise.
For what it's worth my 33 GTR came fitted with one, and after a day it was disconnected due to my beliefs in the above statements :)
 

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From the Racelogic Site:

Spark Cut
Cutting the spark to an engine will stop any chances of a weak mixture occurring, but it carries it's own potential problems due to a large quantity of unburned fuel travelling through the cylinder and out of the exhaust. This petrol can remove some of the oil lining the inside of the cylinder, and pass it thorough the exhaust, again this only becomes a problem if the fuel to one particular cylinder is cut for an extended time. The best way to overcome this is to rotate the order in which the cylinders are cut.

The unburned fuel in the exhaust will have a catastrophic affect if there is a catalytic converter in the exhaust, as it will try to convert the unburned fuel to harmless elements, effectively burning the mixture. This causes the catalytic converter to heat up very rapidly, reaching temperatures in excess of 1000°C, and possibly melting down completely. Thus prolonged spark cut is not recommended for catalytic equipped cars.

Fuel Cut
The idea of cutting fuel to an engine sets alarm bells ringing in engine builders, as they all know of the potential disaster of a high revving race engine running lean. Running in a lean combustion mode will elevate in-cylinder temperatures very rapidly, the denser the air/fuel charge, the more heat the lean burn can generate. Therefore it is vital that a fuel cut system will not cause a lean burn.

The simplest way of preventing a lean burn is to remove more than 50% of the fuel from the pulsed delivery. A mixture will only ignite if the air/fuel ratio is within a tightly defined window, look at the efforts being put into making lean burn engines fire on very low air/fuel ratios (1:20 or more). Removing more than 50% of the fuel will cause an air fuel ratio of over 1:25 and will result in a complete miss-fire, with the unburned fuel passing out through the exhaust valve. Even if a high air/fuel ratio did manage to ignite, the energy available from the amount of petrol injected wouldn't be enough to elevate temperatures significantly. Of course the ideal system will remove 100% of the pulsed fuel delivery, allowing the cylinder to take a gulp of fresh air, and the in-cylinder temperature would remain virtually unaffected. Racelogic Traction Control operates in this manner - the complete injector pulse is removed so no possibility of lean burn can exist.

Prolonged fuel cut on one particular cylinder would cause scavenging of the petrol lining the inlet tracts, and when the next full fuel pulse arrived, it would be partially reduced in quantity by the re-wetting of these tracts. Therefore it is often important to manage a rotation of the cylinder cutting to prevent this situation from occurring.

Rog :)
 

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MeLLoN Stu said:
there's a guy on the SXOC who lost his engine due to bouncing off the limiter on the Bee-R. Bouncing off the limiter basically caused the upper valve assembly to go walkabout, cam jammed, timing chain snapped, goodnight sweetheart so to speak :(

i absolutely hate these limiters, they're totally pikey imo, and yes (also imo) they place monumental amount of strain on the turbo gaskets.
I'm expecting to see a lot of cars develop problems with prolonged use of them. I'm sure there'll be those that disagree, but it's my opinion and i'm sticking to it until i'm convinced otherwise.
For what it's worth my 33 GTR came fitted with one, and after a day it was disconnected due to my beliefs in the above statements :)
Bee-R advise against using the rev limiter on the 20det unless you have fitted rocker arm stoppers. This does not apply to the RB26.
 

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SiKBoY said:
Bee-R advise against using the rev limiter on the 20det unless you have fitted rocker arm stoppers. This does not apply to the RB26.
I didn't know they advised against this! Although I was going to say the SR20DET has this problem, whether the rev limiter is fitted or not, (though obviously fitting a rev limiter like this will obviously find the weakness).

Alex B
 

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SiKBoY said:
Bee-R advise against using the rev limiter on the 20det unless you have fitted rocker arm stoppers. This does not apply to the RB26.
Indeed they do :) I'd rather not invest in them purely for the sake of having a pikey rev limiter :D handy if you want a revable SR though i guess :)
 

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Nocturnal said:
Does using the Bee-R Rev Limiter for fun (just to throw flame to make sure the tailgater back off) cause any damage?

I am just not 100% sure that throwing extra fuel that ignite in the turbo housing will cause no damage at all. Gasket? Will anything in the engine wear?
Anti lag...more or less.

If its stock turbos, they wont last long. The exhaust wheels will snap off.

If its upgraded turbos, anti lag is really rough on parts. Combustion in the exhaust manifold causes a lot of strain.
 

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Cardiff R33 said:
Am looking to get one for drag starts as had the feature on my last PFC, i am sure if used occassionally it would be ok
I've got one, but just discovered that my PFC is a PFC Pro so I won't be needing it. Will know for sure when my engine is done next week.
 

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SiKBoY said:
I am sure if it isnt abused it will be fine otherwise the japs wouldnt fit it to their cars..
Aftermarket turbos. More money than sense.

Its just like a boost controller, just because it can control boost up to 30 psi doesn't mean you should run 30 psi.

Just because other people jump off cliffs, doesn't mean you should .
 

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kismetcapitan said:
I've got one, but just discovered that my PFC is a PFC Pro so I won't be needing it. Will know for sure when my engine is done next week.
no good on my car though, got a 34 gtt!:bawling:
 
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