TrueGS300

Just tossing around some ideas. Some things I'm debating don't seem to be covered a lot. Opinions welcome.

First thing I want to know: Is the only thing stopping the 2jzge from accepting good boost the compression ratio? I've been reading all this info about the stock bottom end being able to handle 900hp and the head also with valve train upgrades and arp head studs etc.

I am planing a build but realized rather than accepting 280-300whp from only being able to push 6-7psi why not move the ratio down to 8.5 like the gte with a thicker head gasket, or 9 to 9.5ish for a less extreme change and push more boost for something in the 400whp range?

My original plan was to swap in BC 264 cams and I will be doing that weather or not a get a turbo kit. It will only make it that much better. But at this time it might be a good idea to go after the head gasket and studs with some upgraded springs and retainers. But does anyone know what that would do for drivablitly when the compression ratio is dropped and the turbo is not in? I am trying to create a build that is easily removed for emissions time in California. I know the cams are ok. But now with thoughts of lowering the compression ratio, I don't know if it would pass smog. Anyone know about this sort of thing? What effect other than a little bit of power loss would there be?

I know what my safest bet is for Cali, but would like to go more if possible. The safest route (for both being undetectable and being able to pass smog as well as not blowing my engine) is to drop in the 264 cams, leave the head and block alone at factory CR. Do a mild turbo kit at 6-7psi with an easily removed intercooler. (I have a OEM Aristo side mount IC and piping I plan to use which I believe should be sufficient for such low psi). And I should be able to get just over the 300whp range. This entire kit would sit in the passengers side of the engine compartment and come out for the stock catted manifold and air box in a matter of a few hours. I need this to be the case for Cali where at any time you can get sent to a referee for legality inspections and tests. The hidden side mount IC is necessary not to be seen like an FMIC that shouts "look at me! I'm illegal!

Or I can lower the compression ratio and and push more.. lets face it, we all want more power!

Another question I have is about upgrading the fuel pump. Does a greater flowing pump overcome the injectors at all on a stock system? For example, say I have it installed to support my cams and turbo kit, but removed the kit to go smog test. Would the OEM pump need to go back in because the high flowing one is sending too much fuel? Would definitely be bad if it was running rich for testing. I'd like to think that the injectors spray precisely what they need to regardless of the pressure (to a point).

Just looking for info/thoughts/and opinions on these things. Anyone with experience and knowledge on the subjects.

TrueGS300

Forgot to add one other idea I had and wanted some feedback on. I've heard of this being done. But unsure of the long term effects if any. But say I leave the head gasket alone, but want to run arp head studs for safety when its camed and turboed. Following sequence and torque specs, could the head studs be replaced one at a time while the head is in place?

captainva

iTrader: (1)

From my understanding the big differences between the GE and GTE are the GE has a higher compression ratio, weaker pistons and rods, and it doesn't have oil squirters installed. I can't speak to how lowering the compression ratio would affect the engine but NA-T seems to be just not worth it in my opinion because the pistons and rods limit the build so much. In theory (people have already done this) you can swap in a GTE and use a USDM supra ECU to run the engine and pass emissions since its OBD2. You would lose some of the features of the car if you did that and you'd need to be really good with wiring though. If CA has a visual inspection that wouldn't work

badblackgs

iTrader: (1)

this guy took a 2jzge and went all in. watch it. he knows his ****.

TrueGS300

There's this source of info on supraforums they call the NA-T Bible for all the GE guys that want to go turbo. I've read some interesting things there. Apparently the crank and rods are the same as the GTE, but not the pistons which are the weak point. The GTE and GE differ in compression mostly due to the head gasket alone, so with a 2.5mm thick head gasket the 8.5:1 ratio can be achieved or any other ratio between desired and calculated. It also spoke of running base timing to retarded 3-4 degrees which can allow the GE to run 9ish psi if I'm understanding it correctly. Easy to do on a non-vvti with adjustable cam sprockets and can be don on the GE vvti exhaust cam.. but unsure how this would be done with a vvt intake cam. So theoretically with all things being accounted for, a basic turbo kit could probably run 8-9 psi safely.

But for the sake of needing the kit to come out for smog time, I've decided not to mess with lowering the compression or anything crazy. I have decided to start my build with the BC 264 cam swap and will get that part done first. I'll have plenty of time to research more about going NA-T as I go. I will likely shoot for a simple 6psi setup to need only a fuel pump upgrade, the ability to run the OEM Aristo side mount IC, no need for ARP studs etc. and hopefully things will go smoothly and stay safe. I'm thinking the 6psi and the cams will be good for 300whp.