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Discussion Starter · #1 · (Edited)
So after lots of debate, I finally decided to build the bottom end and get the head cleaned up. New TT internals, balanced bottom end, BC springs and retainers, Walbro 255 lph fuel pump, 720cc injectors, and I got the head ported and polished. While I was at it, I also added a tranny cooler. I havent figured out what I'm going to do with engine management. Any ideas? I'm going to be picking it up from the shop in a few days. I'm super excited to see how this affects the car na. If I dont like the results, I will boost the car. Dyno numbers and some vids are on there way :) My goal for power is to break 240. We shall see
 

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Sounds awesome, can't wait to see the results!

Question, so you used TT internals on an NA build? I always assumed that the TT pistons were lower compression... which equals less power... correct?
 

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Discussion Starter · #3 ·
Sounds awesome, can't wait to see the results!

Question, so you used TT internals on an NA build? I always assumed that the TT pistons were lower compression... which equals less power... correct?
thats right. the results will be unknown. However, after compression numbers came back the mechanic said that compression was at around oem specs. I'm guessing that maybe the cams have something to do with this. not sure though. I'm looking for allot of mid to top end power. This thing is going to be a screemer. I've been looking at standalone options to really take advantage of this setup. I'm thinking about having the redline at about 8k or so. I have a dd so the idea is for this to be my track car.
 

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Wow... Interesting build. Not sure that I would have gone with TT pistons with the potential lowered compression, but at least now, it'll be bullet proof. I've always wanted to see that a max NA tune would yield and it looks like you have all the right parts.

There is only 1 ECU I'd recommend for you. EMU. You should be able to retain the best features of the stock ECU, while tuning it for the optimum hp that the engine will mechanically make.
 

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Discussion Starter · #6 ·
Wow... Interesting build. Not sure that I would have gone with TT pistons with the potential lowered compression, but at least now, it'll be bullet proof. I've always wanted to see that a max NA tune would yield and it looks like you have all the right parts.

There is only 1 ECU I'd recommend for you. EMU. You should be able to retain the best features of the stock ECU, while tuning it for the optimum hp that the engine will mechanically make.
cool good to know about the emu. thanks for showing up in this thread. i knew you would at some point haha. I wanted to stick with oem tt internals really. we all know these are proven and if i were to boost, my car is ready to handle it. I dont have the compression numbers on me right now but i called the mechanic today and he said that all cylinders were within the normal numbers for the compression. I was debating between the tt internals and bc's 3.4l stroker kit. Obvious setbacks with that setup were first of all uncertainty and second, cost. Right now i think i made the right decision. The car turned on today and supposedly it idled somewhat normal even with the stock ecu.
 

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cool good to know about the emu. thanks for showing up in this thread. i knew you would at some point haha. I wanted to stick with oem tt internals really. we all know these are proven and if i were to boost, my car is ready to handle it. I dont have the compression numbers on me right now but i called the mechanic today and he said that all cylinders were within the normal numbers for the compression. I was debating between the tt internals and bc's 3.4l stroker kit. Obvious setbacks with that setup were first of all uncertainty and second, cost. Right now i think i made the right decision. The car turned on today and supposedly it idled somewhat normal even with the stock ecu.
I think you're confusing compression ratio with whats known as a compression/leakdown test. I'm sure one of the turbo guys can chime in and let you know what your cr is with the GE head and the GTE bottom end. I'd suspect its lower than the stock GE cr. For a N/A build you want to bump the cr up, not down. Higher compresson ratio = higher hp. I think the GTE bottom end is going to hurt more than it helps here.
 

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Discussion Starter · #8 ·
I think you're confusing compression ratio with whats known as a compression/leakdown test. I'm sure one of the turbo guys can chime in and let you know what your cr is with the GE head and the GTE bottom end. I'd suspect its lower than the stock GE cr. I think the GTE bottom end might hurt more than it helps here.
the na race car is300s had gte bottom ends. i'm not concerned with numbers being lower at all. the dyno numbers will speak for themselves
 

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injectors are about 3 times too large, the TT internals will lower the cr, not good for a NA build if anything you would want higher compression, stock fuel pump would suffice for the power your pumping out. You've built your car as if you were going f/i..... You will probably have less power than before.
 

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if you make more than 200-210rwhp I will really be surprised. You really did it quite wrong with oversized injectors, lowered compression (on a small displacement engine too). Why didnt you even add camshafts? modify and redo the intake manifold? etc etc
 

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Discussion Starter · #11 ·
if you make more than 200-210rwhp I will really be surprised. You really did it quite wrong with oversized injectors, lowered compression (on a small displacement engine too). Why didnt you even add camshafts? modify and redo the intake manifold? etc etc
i already have bc stage 2 cams
 

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this is as much of a question as a suggestion... do you think going with a carbon fiber hood and trunk would eliminate enough weight to add some HP? maybe even relocating the battery to the trunk??? just a thought. good luck.
 

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why in the heck would you use 720cc injectors on a NA build? all this money spent to only hit 240 LOL
 

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Yeah, it does seem like you're building for boost and you are practically there with the supporting mods.

The lowered compression will cost you some hp. You'll lose some fuel atomization with such large injectors which will cost you some hp as well.

But let's get beyond that and see where you can go with this.

What headers do you have?
 

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IS300TTRD You should have gone with CP pistons, they are the only people that make an off the shelf 10.5:1 compression ratio piston for a 2jz. The twin turbo pistons should lower you to 8.5:1. Also you are adding mass, have you felt a ge piston/rod next to a tt piston/rod? I will honestly be surprised if you break 175whp. I would go to an AEM, or whatever the tuner recommends, just get something they are comfortable working with.
 

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