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Tuning an n/a


bambisdad

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I was just reading that thread Neil...... What are the goals now then?? Also why in that pm was the title about spooning??

 

Leave it as is apart from a 2nd diff mount, new manifold and tyres and try my best to run a 13 sec 1/4.

 

Removed at your request (might want to edit your quote too ;) ). I thought it was a relevant discussion even if you chose not to do it.

 

I was only having a mess mate, stick it back on if you want, though it does make me cringe as i well and truly spat my dummy out after that thread.

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Leave it as is apart from a 2nd diff mount, new manifold and tyres and try my best to run a 13 sec 1/4.

 

 

 

I was only having a mess mate, stick it back on if you want, though it does make me cringe as i well and truly spat my dummy out after that thread.

 

Good luck to you mate would be good to see a fast Na time and not just some of the youtube videos either... On another note Ed said something about you and him having a "special" evening planned tonight??

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Good luck to you mate would be good to see a fast Na time and not just some of the youtube videos either... On another note Ed said something about you and him having a "special" evening planned tonight??

 

I believe we are going drinking beer then finding a goat to rape.

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Go high compression, maybe even use meth/water if your worried about getting knock. Sorted. May even be around the 300 mark? Maybe custom cams if the new pistons are light enough raise the redline `slightly`, maybe change the rods and raise it safer? Port the head and its SERIOUSLY tiny flow holes.

 

I want to get my ported, group buy on port & polish :D

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Would be interesting to see someone try the higher compression Toda 2JZ-GE pistons

 

It would yes but I have my suspicions that without some head work and possibly cams I don't think you will achieve a huge gain.

 

No point in fitting higher comp pistons if the head isn't capable of filling the cylinders with more air.

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Port the head and its SERIOUSLY tiny flow holes.

 

Id hardly call the ports tiny at all. If your trying to keep the car streetable then there isn't much you can improve on over stock.

 

If you don't care about any low down performance and a decent power band then go with the American methodology of bigger is better.

Edited by Kirk (see edit history)
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Get a nice 5.7 LS1 engine from the states and have a lovely V8 in there which has 350 hp & 365 ft lbs torque

from stock without turbo's

 

I know a man that already fits these into RX7's and boy do they go rather well :)

 

Hi Dunk,

 

Will your friend be able to drop a 2JZGTE from an Aristo into an IS300? If so, we need to have chat ;)

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Hi Dunk,

 

Will your friend be able to drop a 2JZGTE from an Aristo into an IS300? If so, we need to have chat ;)

 

 

I guess so but no idea what kind of cost would be involved, has it been done before, is much required to do it.

 

I think if its the first one he's done then i doubt it would be very cheap.

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Will your friend be able to drop a 2JZGTE from an Aristo into an IS300?

 

If you already have the 2JZ-GTE from the IS300 then it should be just a case of swapping some of the parts over onto the Aristo 2JZ-GTE so it'll fit.

 

I built up my engine using parts from my trashed Supra 2JZ-GTE and a JZS160 VVTi 2JZ-GTE, by swapping the head, oil pan and other bits and pieces.

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Id hardly call the ports tiny at all. If your trying to keep the car streetable then there isn't much you can improve on over stock.

 

If you don't care about any low down performance and a decent power band then go with the American methodology of bigger is better.

 

Your right mate. I forgot it would be NA without boosting, I was thinking about what I'm hoping to do with boost. Silly me, the low end power would reduced.

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No point in fitting higher comp pistons if the head isn't capable of filling the cylinders with more air.

 

With repsect that's completely wrong.

 

Increasing the geometric compression ratio increases the efficiency of the combustion process by inceasing the amount of energy that goes into gas expansion (as opposed to being lost as heat). The downside is the risk of knock at high loads when the cylinder is at its most full at the end of the induction stroke. Engines are terribly inefficient at low loads beacuse the actual compression ratio is tiny because of the partial cylinder fill when the throttle is partly closed. this is why you never get knocking at low loads.

 

In fact the better the cylinder fill (the higher the volumetric efficiency) the more likely you are to have to reduce the compression ratio (i.e. as is usual in a forced induction engine).

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I think it costs around 10k to get 300hp out of an N/A while keeping it as an N/A, good as an excercise for a company to do but mental for a normal owner IMO.

 

I've looked into it extensively as a "works" project here, even done a couple of proto-mould heads with vvt/lift on both cams , but decided it's not worth the machine time and money given that the first response if I pulled up at a dyno with just over 300 bhp would be "why didn't you charge it instead" for far less money and far bigger horsepower

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Dam straight. Forced induction is the way forward. First options to get anything more than 20bhp on an NA engine should be a forced induction. Its a shame not more power can be gained from the stock NA engine, but its been tried tested and EXPENSIVE.

 

NA engine CAN produce good power. But your need a turbo or supercharger (if your really swish). Simples :)

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You all talk about making xxx amount of HP but why does no one talk about how to make them faster? light weight, good tyres, better driving etc.

 

If records are true on the 1/4 mile with my shoddy 232bhp i have a higher mph than an NA with 285bhp* and am 3 mph off a car that was running 100 shot of nitrous (in theory could be around the 300hp mark), so either i am really good at driving (60fts would show otherwise) or these guys aren't.

 

*yet to be proven.

 

When people ask what i'm doing with my car they always assume HP, nope i just want to make it faster down the 1/4.

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I've looked into it extensively as a "works" project here, even done a couple of proto-mould heads with vvt/lift on both cams , but decided it's not worth the machine time and money given that the first response if I pulled up at a dyno with just over 300 bhp would be "why didn't you charge it instead" for far less money and far bigger horsepower

 

Hang on hang on hang on :) You can't come in here with a two line post suggesting you've designed your own cylinder head with dual variable cam timing and lift and then not tell us the rest! If I'm right then practically no one even in OEM world is doing dual variable valve lift - maybe no one at all, yet.

 

Who's variable lift hardware did you use? Adapting the 2JZ head to variable valve lift on its own is going to be a proper old tear up unless you used the switching tappet from INA (as used by Porsche).

 

Did you get as far as casting the heads?

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With repsect that's completely wrong.

 

Increasing the geometric compression ratio increases the efficiency of the combustion process by inceasing the amount of energy that goes into gas expansion (as opposed to being lost as heat). The downside is the risk of knock at high loads when the cylinder is at its most full at the end of the induction stroke. Engines are terribly inefficient at low loads beacuse the actual compression ratio is tiny because of the partial cylinder fill when the throttle is partly closed. this is why you never get knocking at low loads.

 

In fact the better the cylinder fill (the higher the volumetric efficiency) the more likely you are to have to reduce the compression ratio (i.e. as is usual in a forced induction engine).

 

Yup reading that back I can see where I went wrong there.

Now correct me if I'm wrong here, lets say for example an engine with cylinders of a 100cc and a 14:1 CR is only filling 50cc of fuel and air into the cylinder itself that would make the VE of only 50%. Theoretically speaking that engine would only be running on a ratio of 7:1 am I right in saying? Obviously though for an engine to be that volumetrically inefficient at full throttle it would have to be seriously restricted but you understand what I'm saying I think.

 

What I meant by that statement is if the VE of the engine is poor to begin with then just upping the CR wouldn't net you much of a gain without first improving VE.

 

I'm probably wrong but after all I only have my L plates in terms of engineering with much to learn at the minute :D

Edited by Kirk (see edit history)
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