Progress on the G4X!
Today, I finally had a chance to test the flat shift logic with the stock FD gearbox and also start the process of retuning the new ECU.

3rd - WOT around 3700rpm
Boost - 1.2psi



Shifted up around 4500rpm - still at WOT!! .... A proper **** my pants moment...hoping the logic works as it should...if not gearbox RIP!
Boost approx 11psi


Still WOT in 4th - the logic worked as it should and gearbox / engine still in one piece.
Boost at approx 4psi. (Normally would be in vacuum -10psi)


Test results are promising!

Previously, during gear changes, boost pressure would drop significantly into vacuum (-10psi) before ramping back up again. This time, however, the boost pressure remained positive throughout the shift. While shift times haven't improved (still around 400ms or 0.4s), the boost response can really be felt behind the wheel. The car feels awake!

I'll do a 100-200 to compare the traditional manual shift to the new flat shift at 15psi to start with. Since the turbo remains in boost during the flat shift, I expect it to deliver more power and torque under the curve, potentially leading to faster 100-200 time.

Flat Shift Feels Great!
For those new to the concept, see below a regular upshift involves lifting off the throttle, which causes the boost pressure to drop significantly into vacuum before ramping back up again. The flat shift function eliminates this boost drop, keeping the engine "on boost" during the shift, making the car feel more responsive and powerful. Although, a common Motorsport function its seems to work with the stock synchro transmission. I suspect a Dog box, ZF8 and DCT will do the same for boost response, perhaps better boost response as they will shift faster than 0.4s.

 

very cool perk for the Link ECU.

 

Interesting, I'm presently running the older G4+ Fury, and this looks like another good reason to upgrade to the G4X/G5 series... How exactly does this get implemented with the ECU - does it just need a clutch switch input to sense when you're shifting, and I assume a DBW throttle setup fitted, and then tuning the flat shift feature in the software? I already have a DBW throttle and a clutch switch wired in, so since the G4X & G4+ Fury's share the same connector pin-outs, there would be zero wiring changes

 

It's a super feature and seems to work the stock synchro box. Clutch switch as a digital input for the ecu to detect the clutch input (on upshift) to cut ign and prevent engine rpm's from skyrocketing and destroying the box/engine. Once clutch switch disengages the ECU reintroduces power and torque based on the logic applied.

 

What a cool feature. I assume the upshift switch is the clutch switch which correlates to the 0.4s

Must be unsettling; not letting off the gas while shifting.

 

Correct, its the time to complete the manual shift.

Yes, felt unnatural the first few times i tried it as muscle memory dictated coming off the throttle.

 

there’s nothing more unsettling than making a no-lift shift without a cut
.

 

@rx7srbad Not sure if you saw. Link have released a new update for X series ECU's I believe that allows a 3rd stage of injection so you would not have to bring 4 injectors on in one go. Might be worth looking at.

 

I have not and thanks for the heads up.

 

Nice! The new Mustang GTs do that from the factory (along with some other cars). I worked with Ford on the development of that programming back in 2016 (which finally now made it into the base Mustang). Once dialed in, it's a pretty cool feature.

 

I mean its no replacement for a seemless shifting DCT box but every little helps in the 30yr old manual box. Even if it means you gain a 0.1s or 0.2s advantage because turbo remains in positive boost...that is a major bonus in my eyes.

 

The build continues with a focus for faster and more reliable acceleration. The goal is to consistently accelerate from 100-200 km/h and 200-250km/h in the mid 4s range or there abouts because high 5s range was the trend 2 months ago.

Looking at my I data dont think a G40/G42 will cut it. So I'm considering selling the beautiful SAS manifold. It was built by Steve for a larger BW S366 turbo frame and my initial plan was to run a G40. Thinking I need a G45 turbo, which should do well with the Turblown UIM. I dont know if the the mani can fit the larger frame G45 turbo so not holding my breath. Not certain if a Turblown ewg mani will fit a G45. Will cross that bridge when i get to it.

Before that, I want to max out the G35 with the new fuel system to 32psi. I'm expecting it to hit its limit on a street port and will be interesting to see what it does and how well it accelerates.

Parts are coming together:

• 2x Turbosmart 14psi wastegates
• Turbosmart BOV
• Turbosmart FPR8 fuel pressure regulator

Nothing wrong with my current AEM FPR but as my goals have changed I decided to go with the FPR8.


To address the fueling I decided to go with radium primary and 4 port secondary rails. The package however arrived highly damaged, which did not fill me with confidence.




The rails looks fine from the outside but there are severe manufacturing defects which pose a serious fire risk.



Just one end of the primary port as pictured below...the an8 orb wont seal and the tapering is shredded. This is similar for other ends of the rails and the secondary fuel rail on the inside has very sharp edges. Radium UK advised they would send a replacement which is yet to arrive. Not the build quality I would expect from a premium manufacturer.



Got a speeding fuel filter with a 10 micron stainless element which supports all the flow, its good for 1500hp+.
Decided to get 4x Flow matched 2200cc bosch injectors for all the fuel.
I'll resuse my ASNU 2x1500cc as primaries which takes care of the fueling requirements.




To help with traction I decided to go with the ATS carbon 1.5 way LSD which i'm told by ATS and Tim is very oem like in its function with no additional NVH or chattering issues.




Tim from RX motors sourced me an auto 3.9 final drive with a case to eek out even more mph at the top of 4th.


Draggy GPS confirms I hit 130mph or 210km/h in 4th gear at 7900rpm. Gear ratio calculations suggest I need 9k rpm for 150mph in the same gear with my current 4.44 final drive.

The idea of switching to a 3.9 final drive is to let me hit 150mph at a more suitable 8000rpm. I'll experiment with different final drives to optimize 100-200km/h and 200-250km/h times. Watch this space.

 

As if Omar's 100-200 time wasn't already impressive at 3.96s, the man has stepped it up even further.


100-200 - 3.77s
200-250 - 3.36s (The top end is ridiculous, getting closer to 2s range)

Since this run was on a drag strip, it won't qualify for the 13B RX7 Leaderboard. Still, it's definitely worth sharing with the community, especially considering any modern car in this power range is pushing 1000+whp.

This run gives me even more confidence that cracking into the mid-4s is absolutely achievable with the right supporting mods on a 13b Street port.

 

1. Won't a 3.90 final hinder your acceleration?

2. What porting and turbo is Omar running?

3. My Radium primary was exactly like that. They said that's how they are and won't be an issue. I took a dremel to it to smooth it out. I'm surprised they're giving you a replacement!

 

in a few weeks will be doing a run across the road which is an unprepared circuit track so will see how she goes there, there is also abit more slope on that straight. Maybe by then I will have a bit more boost. I did a hit on the road yesterday and it actually hooked so I am confident it won't spin but only time won't tell.

 

we make a rail kit that doesn't have defects like that for anyone that's interested.

Part I don't get is why you all want a Dash 8 Rail for 2 Injectors.

When we did the testing for Fuel rails we tested our AN6 rail with two 5500cc injectors and could not out flow the feed line

AN8 would be required for 4 injectors at 5500cc per injector (Not at 2600cc)

 

Yes, it could. Trying to find a balance to hit 100-200 and 200-250 on the stock fd box with just 1 shift from 3rd to 4th as this is ultimately faster than doing 2 shifts with the current 4.44 fd.
I dont know....will have to test and see what works.

 

Sounds good and keep it safe.

 

I asked a local builder/tuner with decades experience about my idea to go 4.44 (i'm planning to run 1/2 mile) and he said to stay with the 4.10 and if possible go with a shorter 5 from a jdm transmission. I didn't ask about the 3.90 so I'll been watching your results!

 

Def makes sense, for half mile you want the 4.1 or 3.9. The idea behind me choosing the 4.44 was for track use and in a way its done better than expectations for the 100-200 sprints.

The 200-250 has not been tested but will get round to it on the 4.44 and 3.9 soon. I've even got the stock 4.1 so quite a few options to play with.

Also i'm on the shorter JDM 5th.

 

im on a 4.30 diff and my 5th gear is 1:1 (dct)
shifting at 8500

 

i am curious as to if you can carve out a section from your dragy data...

i have been doing road tuning and during the last 4 years when i lived in the mountains i could only do from around 72 to 104 due to lack of straight road. recently i moved and am no longer road limited. because i have a few hundred 3rd gear pulls in the 70-100 area i have stuck w that as to E T data but am now able to run past that in 3rd. (the car started to go sideways at 114 on the run- 593 hp at 8008).

yesterday i did 72 to 104 in 1.309 seconds. 24.4 mph/sec. if you can carve that out of your dragy data how does that compare?

run was done w my G40-1150 at 23 initial to 22.1 at the end and was rich at 9.6 ending at 10.3. 60% E.

the G40-1150 is starting to get into its happy zone. around 80 pounds. only 243 F out of the turbo and 73 into the motor all V thermocouple.

Link Extreme G5, Turblown UIM, CPR turbo manifold, WG plumbed into downpipe, 3 inch exhaust. more boost than backpressure to 6550. 35% more backpressure than boost at 8047. CPR ports... no BP, no PP.

power and torque numbers:

5000 421 442
5500 480 458
6000 480 420
6500 503 406
7000 522 392 9.69 AFR
7500 582 407
8008 593 389

EGTs at 8008 1714 and 1717 timing 9.6 14 split

revisiting the log and extending using the last data point at 100% TPS... i find 112 mph, 8008 RPM, 22.0 boost, 10.30 AFR. total E T from 72 mph to 112 was 1.613 seconds or 24.79 mph/second.

115.8 to 180.2 KM

 

72 mph to 112 in 1.613 seconds is lightning fast, like drag racing territory per the draggy verified reports I've come across. It would be interesting to see how this reflects on a verified draggy run. I think we are comparing apples and oranges because we're looking at non verified times vs verified Draggy GPS data.

The verified times for my FD
70 - 110 mph - 3.83s
100 - 180 km/h - 4.57s

and for reference Omars 800hp+ FD does

70 - 110 mph - 2.25s
100 - 180 km/h - 2.80s

If you get a draggy device you can do custom mode runs like a 60-100mph or whatever parameter you choose for the tarmac you have to safely conduct the runs.

 

Thanks for the response and thanks for your comments. it would certainly seem that my time would be significantly slower than Omar as i am nowhere near 800 hp. OTOH, i have checked both time from the log and mph numerous times. while the run from the cockpit seemed to be as fast as the time i am still looking for answers that would put it in what seems to be a more realistic context given i was around 600, not 800. i didn't include the meth BTUs but that is just another 20 hp.

here's 70mph:



i can't think of a reason to doubt the Link time: 4 minutes 44.502 seconds
5027 RPM, 70 MPH 3rd gear in my Tremec Magnum F. speedo correlates as well as speed from hundreds of other 3rd gear runs. 21.1 boost, 11.72 AFR

here is 110 mph





110 mph time is 4:46.242.

4:46.242 - 4.44.502 = 1.74 seconds

checking mph:

110/70 = 1.57

5027 X 1.57 = 7892 RPM. my log shows 7867

i will look into dragy,

 

here's a dragy chart from Esser. I believe around 800rwhp. You can calculate the 70-110 time...2.42s. I have noticed Dragy times have differed from HPTuners' times by as much as 0.2s. Also with the Dragy unit sitting on my counter top the altitude varies by as much as 180 ft.