Yeah. Post in here. Or start a new thread
1FZ-FE Stroker Build (5.5L - 102mm Bore - 115mm Stroke) (1 Viewer)
- Thread starter ToyotaIsLife
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Yeah. Post in here. Or start a new thread
Have you ever heard of Rotrax superchargers? I learned about them fro the UAE website. I think that is what I would try if I was going for a boost.
Centrifugal superchargers - Improved performance of your car
Rotrex offer a standard program of superior centrifugal superchargers as a bolt-on addition to improve performance of your car or motorcycle.rotrex.com
This style supercharger is used quite a bit in Australia in various cars because they are easier to fit under the hood
مرحبا الشيخ وكل التوفيق.I just read this and laughedthis is spot on. Even more so now that I have more 1FZ-FEs to work on.
Even if a certain change worked out well and noticeably improved power my mind just never stops. It’s always onto the next thing. Addiction. No responsibilities no wife to worry about wake up check on my university assignments and on to the workshop! This is gonna be short lived so I have to make the most of it.
I want to try individual throttle bodies (one throttle body per cylinder) with a short path to the cylinder, I want to try playing around with headers as well, shortenining the primary pipe length and enlarging the diameter to move peak torque even further up to see how that does with a big cam, the further you move the peak torque up the higher the HP since (HP = torque * RPM / 5252) with this in mind how far can we push it to gain the best peak HP? Even though that would mean the low end and mid range is going to suck.
On the flip side, I want to try a dual throttle body setup with a hybrid intake manifold and a flapper actuated by the ECU. Where a longer path is used at low RPM and a shorter path is used at high RPM inspired by Nissans intake on the TB48. To give a really broad powerband as far as the intakes concerned. Really curious to see how this one goes and whether it will actually deliver the kind of performance I’m expecting. The flapper would be connected to the ECU as an auxiliary output and would be controlled with a table where it alternates at a certain RPM range and manifold pressure.
We will see how all this goes in the future.
When it comes on how far you can rev the engine, it is all in the cylinder head flow and the correct induction system.
You need to start first with head.
Stock 1fz heads only flow 245 cfm (@28") at 0.5" lift.
I have a flow bench and have checked several local hand porting and also CNC programs and the best I have seen is 310 cfm. Some barely flow 290 cfm at Max lift.
Mind you these are customer heads and not the heads you will get if you have deep pockets or great contact with shop owners. Off the shelf kind of thing with minor due delligence done after porting.
I have seen your dyno graph and you had peak power at very low rpm (4k) indicating induction system restriction.
1fz cylinder head should be capable of flowing 360 cfm easily at 0.5" of lift with 39.5 mm valve.
once you have a good flowing head then next fabricate a 10" runner intake manifold with a 2.5" bellmouth entry that tapers to the port entry at 2".
Club it with a good header and high compression (12:1) and the right cam.
You should achieve peak power between 5000 to 5200 FPM mean piston speed.
If you ever pass by UAE and have your cylinder head, am happy to support you in flowing it.
Good luck with your pursuit of HP.
Abdulla
- Thread starter
- #104
Thank you for sharing.
Your correct, even if I install a really large cam with really high duration and allot of lift it’s still going to be limited to how well the head flows. Thank you for bringing that to my attention, head flow CFM I completely forgot about that.
But keep in mind also that the dyno photo you saw of my stroker build at the beginning, the one where you said it had peak HP at a low RPM was mainly due to the small cam that it had that time, the head flow was not the bottleneck since it moved up quite a bit and held power up till 7000rpm when I installed a larger camshaft.
The stock heads look like there's a decent amount of opportunity to improve flow with a bit of hand porting and deburring/smoothing
- Thread starter
- #106
Exactly and I tried 1FZ-FEs that were completely bone stock with just a head port and polish, and I also did the same combined with larger valves (1.5mm) as well. It gains quite a bit of torque down low surprisingly with the latter combo even with a stock ECU, I have a thread on this forum showcasing that with dyno results that showcase a substantial gain in low end grunt which still shocks me since I did that test with the belief that larger diameter valves and intake and exhaust ports would shift the powerband up due to reduced velocity, but apparently that was not the case, the peak torque RPM went down not up alongside it being higher (gained around 60 pound feet).
But you will not make full use of it without a larger camshaft off course. The power does die off after 4,500 on the stock camshaft it wants significantly less fuel above 4,500 and keeps wanting less up till 5,500 which further illustrates that it isn’t flowing, which I imagine isn’t a problem if you do not care about the high end.
