Would it add reciprocating weight to the rotating assembly? Absolutely.
Is it a cost-effective idea for a NA setup? No.
It sounds like you are going for a serious NA setup. I would try to lighten the rotating assembly, slightly raise the CR, let the engine breathe better (head porting and cams), and increase RPMs to get the most out of your NA setup.
I am new to the 2jz-ge engine (very new) but not new to engines and engine building/tuning. However, this would apply to any NA engine wanting to increase power.
From what I have been observing there are not a lot of people building serious NA setups (except Team Lexus). Why? Because it is probably more cost-effective (bang for the buck or HP/dollar) to build a boosted setup. Albeit, a boosted setup is expensive. But, the HP/dollar ratio would be more favorable than a serious NA build.
When I mention serious NA setups I am referring to higher compression pistons, lighter rods, lighter crank, head porting, etc. (engine work not just bolt-ons).
To answer your question regarding a 2.4l stoker kit, 13:1 static CR, and water/methanol injection...is it possible to run this setup on pump gas? Sure, it is possible. Is it practical? Not so much.
With proper engine management you can run high static CRs on pump gas by taking out timing and optimizing AF ratios. Your margin for error becomes smaller when running higher static CRs on street gas (i.e. get a bad tank of gas or a hot day).
But, if you were going to go with water/meth injection why would you not run race gas on a high compression NA setup?
Would it add reciprocating weight to the rotating assembly? Absolutely.
Is it a cost-effective idea for a NA setup? No.
It sounds like you are going for a serious NA setup. I would try to lighten the rotating assembly, slightly raise the CR, let the engine breathe better (head porting and cams), and increase RPMs to get the most out of your NA setup.
I am new to the 2jz-ge engine (very new) but not new to engines and engine building/tuning. However, this would apply to any NA engine wanting to increase power.
From what I have been observing there are not a lot of people building serious NA setups (except Team Lexus). Why? Because it is probably more cost-effective (bang for the buck or HP/dollar) to build a boosted setup. Albeit, a boosted setup is expensive. But, the HP/dollar ratio would be more favorable than a serious NA build.
When I mention serious NA setups I am referring to higher compression pistons, lighter rods, lighter crank, head porting, etc. (engine work not just bolt-ons).
To answer your question regarding a 2.4l stoker kit, 13:1 static CR, and water/methanol injection...is it possible to run this setup on pump gas? Sure, it is possible. Is it practical? Not so much.
With proper engine management you can run high static CRs on pump gas by taking out timing and optimizing AF ratios. Your margin for error becomes smaller when running higher static CRs on street gas (i.e. get a bad tank of gas or a hot day).
But, if you were going to go with water/meth injection why would you not run race gas on a high compression NA setup?
My $0.02
-kenji
i think he has the altezza - or maybe an is200
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Would it add reciprocating weight to the rotating assembly? Absolutely.
Is it a cost-effective idea for a NA setup? No.
It sounds like you are going for a serious NA setup. I would try to lighten the rotating assembly, slightly raise the CR, let the engine breathe better (head porting and cams), and increase RPMs to get the most out of your NA setup.
I am new to the 2jz-ge engine (very new) but not new to engines and engine building/tuning. However, this would apply to any NA engine wanting to increase power.
From what I have been observing there are not a lot of people building serious NA setups (except Team Lexus). Why? Because it is probably more cost-effective (bang for the buck or HP/dollar) to build a boosted setup. Albeit, a boosted setup is expensive. But, the HP/dollar ratio would be more favorable than a serious NA build.
When I mention serious NA setups I am referring to higher compression pistons, lighter rods, lighter crank, head porting, etc. (engine work not just bolt-ons).
To answer your question regarding a 2.4l stoker kit, 13:1 static CR, and water/methanol injection...is it possible to run this setup on pump gas? Sure, it is possible. Is it practical? Not so much.
With proper engine management you can run high static CRs on pump gas by taking out timing and optimizing AF ratios. Your margin for error becomes smaller when running higher static CRs on street gas (i.e. get a bad tank of gas or a hot day).
But, if you were going to go with water/meth injection why would you not run race gas on a high compression NA setup?
My $0.02
-kenji
A few things I would like to point out.
First how do you raise the rotating mass with oil squirters? Oil squirters are like little metal hoses that spray oil to the underside of the pistons. They are usually mounted to the internal part of the block not the pistons or rods or even crank. So that argument is null and void
On the otherhand, I do not believe that oild squirters will be your ticket to running more compression. If you saw how an engine run, you will see that engines get more than enough oil splattering on the underside of a piston. The oil squirters imo do not do much more. Most high HP Supras block them off anyway.
Cost effective? well not when a stroker kit can be had for less than $4000. yeah boost will always win in the end when trying for more and more power. But please visit the 'go faster' forums to see how they are fairing with their supposed budgets (which usually turns out to be twice as much as they anticipate).
Detonation resistance.....come on here, there is no point in even discussing this. Even at 13.0 compression ratio NA, I will always take my chances with that NA than a 8.7:1 compression ratio boosted car when you introduce detonation. Boosted cars can only detonate so much, some NA cars (almost all Toyotas for instance) go as far as design the ecu to allow a cetain amount of detonation especially when the load levels do not exceed a preset amount(read your manual, its there ). Every Toyota I have ever driven in any great amounts of time (Lexus's included) will detonate at some point or the other (mild and not so often) and yet they last to 200+K miles.
At first glance my statement that oil squirters increase rotating mass sounds like nonsense.
However, the oil squirters do indirectly increase the weight of the rotating assembly by squirting oil on to the piston. This, in turn, runs down on the rod. Oil does have mass.
Although the amount of oil on the piston and rod is small at high piston speeds it can substantially increase the forces imposed on the rotating mass and bearing surfaces.
This may sound like I am splitting hairs but it is a fact. Some high output NA race setups (Honda DOHC VTEC B-series) actually remove the factory squirters for this very reason to optimize high RPM (10k+ RPM) operation.
The purpose of the oil squirters is to cool the pistons to prevent detonation and this is great for everyday driving. For a 1000+ Hp Supra or a 300 Hp 1.8l NA DOHC VTEC B-series engine spinning at 10k RPM they are not necessary.
So, although it sounded like nonsense at first there is merit to my statement of oil squirters increasing the mass of the rotating assembly.
eh i can vouch for the effect of oil squirters on a turbo motor, being that they help prolong the life of the engine, by helping the pistons run cooler you run into "piston slap" MUCH MUCH further down the line. Oil squirters are not needed NA.
You would be much better off running a higher CR maybe 12.5 : 1 with a shaved head and smaller gasket to run an extremely tight squish area. maybe in the neighboorhood to .030. or groove the head to help with detonation resistance at that CR. just a 3mm wide groove at the top tapering down about 2 mm deep aimed directly at the spark plug. I'm sure you could get away with 12.5 CR and some decent timing advance on 93 octane.
If you are curious about the Grooves lookup Somender Singhs groove theory. Seen some really good results with them.
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I am sure that is what the squirters are for, you are right in that in could add some weight to the pistons. But take a look at a running engine, the amount of splashing oil that hits the bottom of the piston on any engine that does not have squirtors, you will wonder why they are even there to begin with. There will always be oil splashing on the underside of a piston in any car, therefore increase in piston weight as a result? I dont think so.
Think of this analogy....splash water on your face with your hands, then add a eyewash, yes there is more water, but the amount of water that actually STAYS on your face remains the same. IE there is more fresh water hitting your face, but the actual amount of water on your face is the same (run-off).
About the Honda high rpm cars, if my memory serves me right, I believe they are removed to make sure oil pressure does not drop at a very high rpm.
Truth be said, one comment an engine builder said when he saw the pics of the 2JZ head was that it had a very inefficient combustion chamber design and could be prone to detonation. Another one of my buddies made the same comment when I described what the combustion chambers were like to him.
The problem is that there isnt much of a swirl or much of a way for the air to mix up more efficiently to produce a finer mix of air and fuel and prevent pre-ignition. Thats why you see boosted guys with a cast iron 2JZ running less than 16 degrees of total timing advance. Even there you have to remember that psi forces the air to move around a lot so there is more mixing , but ultimately combustion chamber design if what decides how well.
Honestly we are stuck with using cams and reducing timing to raise compression. Oh also since the IS store has Coolingmis , a little aqua spray will go a long way.
You are right about oil pressure at high RPMs and the removal of the squirters. That is a part of it. The other part is reduction in reciprocating mass.
The water analogy is somewhat valid. Oil has slightly different characteristics/properties when compared to water (i.e. viscosity) and will tend to "adhere" to surfaces better.
I think we can both agree that the dynamics in a crankcase at high RPMs are hard to determine from engine to engine. I think we can also agree upon the fact that oil from windage does make its way on the rods and possibly the pistons.
I think we can agree to disagree that oil squirters increase reciprocating mass by squirting oil on to the bottoms of the pistons. I say it has some effect and you say that it has little, to no, effect.
Ok I understand that oil adheres more than water. But what I am saying is that there is already oil on the rods, crank, and lots of splashing of oil under the piston as it is. The oil is already there and therefore any increase in reciprocating mass will be there squirters or not.
We used windage trays to reduce oil splashing in mustangs, the power gain from that was about 10rwhp. Thats from a car w/o oil squirters. My point is that the oil will get there anyway so squirting more oil will help cool it down, but not add weight.
Sorry guys i havnt been able to kick this around with you been busy with life stuff.
Thanks for your input .
Its a supe na engine was looking at gte block for the squirters as the rest will be up graded to superior hard ware .
Wanted to run on street for reliability see how long & any probs .
Our pump gas over here is 98 octane or 100 ethnol blend will research the diff between yours & our numbers.
Aim is qucikest street tyred n/a 2j in aus .
In my opion your site is the best 2j na site in world , + rep to all you enthuist,s.
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