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running 1.9 bar


spiderpigcity

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I would say it's madness. I have an all steel Skyline engine built on all brand new parts and I only run it at 1.3 bar. I might risk 1.4 bar, anything more I would most definitely want race fuel in it. You MIGHT get away with an odd quick squirt up the road, with good mapping, but don't try a track day at 1.9 bar!

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I would say it's madness. I have an all steel Skyline engine built on all brand new parts and I only run it at 1.3 bar. I might risk 1.4 bar, anything more I would most definitely want race fuel in it. You MIGHT get away with an odd quick squirt up the road, with good mapping, but don't try a track day at 1.9 bar!

 

Funny you say that, Chris. I don't want to go above 1.5bar on mine, purely for the fact I'm not running a forged block. I want reliable-ish :)

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I would say it's madness. I have an all steel Skyline engine built on all brand new parts and I only run it at 1.3 bar. I might risk 1.4 bar, anything more I would most definitely want race fuel in it. You MIGHT get away with an odd quick squirt up the road, with good mapping, but don't try a track day at 1.9 bar!

Chris in your opinion how would Meth injection change things if used at this pressure

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Chris in your opinion how would Meth injection change things if used at this pressure

 

it's more to do with atomization of the fuel at high boost with high intake temperatures, although afr readings are good they only give an average and there are pockets which go into the cylinders with different ratios of fuel e.g. some pockets may be mixed at 18:1 and some at 10:1. this is the problem causing det issues when running higher boost. thats why tuners fuel rich to be safe but this doesnt really sort the mixing problem and high temperature issues. I just wondered what people have successfully ran thats all.

 

yes it would but at correct ratios

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1.4bar on hybrids is a lot less air/pressue in the cylinder, isn't it?

 

The air pressure due boost is not the issue , cylinder pressures during detonation can go into thousands of PSI , the engine does not instantly fail, the boost pressure is one of a few variables that cause peak cylinder pressure -

compared with the pressure from combustion it is small .

Det is the worry - and the rise of det with boost - hence fuel octane needed -

or water injection as anti det

Det is complex as a few things effect when it starts , some you can alter some not

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8.40 @ 167mph stock pistons

Current personal best for the Forcefed team and dipping the Supra deep into the 8 second mark. Still using stock pistons and factory mains. Chassis is certified to 8.50 and the night was over due to restricions.

 

1.28 60ft

135mph 1/8

8.404 @ 167

 

Video

Video 2

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Running 1.9bar on a stock compression motor you risk high det on 99 octane fuel, you might get away with it for a while with race fuel,

you are going to need to back the ignition timing off so much that it will likely cut any gains by a fair bit, the way to do it is to match the boost with

the compression ration, but then there is the problem with if you go too low on compression you will loose of boost power to, its swings and roundabouts.;)

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8.80 Stock Pistons

Hi there it has been a long wait for some decent weather here in Vancouver and we were out testing our inhouse build. Just thought we would share our findings and show the quality of factory toyota parts. We went 9.1 on a stock block and head last year and found that in the quest for an 8 we bent all the connecting rods. So we started with a used jdm engine and just replaced the rods with some scatt h-beams. So all factory equipment was used other than the rods and the cams are BC 264.

 

We had trouble with the th400 and the pass would have been much better if we had all of top gear. You will see in the top end that the trans slipped and hit the limiter.

 

The car held 1000hp through the th400 for 38 passes on the dyno. Also held a 175 shot through first two gears at the track.

 

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The stock rods started to bend or de-stroke after many passes with 850rwhp through the auto. I knew this as the boost had to go up to maintain power! When we attempted to go 8's on the same block we turned it up to 950whp and that is when the number 1 rod hit the lower cylinder bore and broke the piston up. Remember this is through a th400!

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