Project Supracharger

Here it goes again.

Flappy-paddle operated ignition retard to 6° BTDC is wired to ECU and functions perfectly, on and off-able with O.D. button, street-mode and race-mode.

Red triangle is out at last and set to illuminate if the AFR runs lean.

AEM EGT sensor is speaking to the ECU.

No vacuum leaks neither.

At 1.1 bar boost the inlet temp with charge-cooler and without water/meth was ambient @ 20°C.

The good news is that everything functioned perfectly and survived, even.

There's more torque bottom and mid-range and after giving another 10 bhp the engine is then choking @ 6k rpm.

Talked it through with Dan and Ryan and consensus is the exhaust gasses can flow no more.

We tried the exhaust cam 2° either way during the last mapping, both lost power.

N/A cams are lairy-in and lazy-out and over 6k rpm the supercharger is pumping in more than can get out.

[video=youtube_share;bpiGM23-R8g]

The smoke after the bang is from the supercharger belt slipping when the engine is choked

Previous graphs

Todays graph

338 ftlb and 367 bhp at the hubs.

@ correction 1.13

382 ftlb and 415 bhp at the flywheel.

The powerband is now wider, there's more torque at the bottom end and the curve is flatter.

The water/methanol system actually reduced power, it's running @ 15% fuel parallel which is supposed to be the optimum, yet Dan reckons half that would be enough.

I'll get an exhaust pressure sensor into no. 1 primary and see what it shows up.

I have a less-lairy U.K. T.T. inlet cam that I could fit which might be an improvement, yet the reality is, to go further it needs larger bore exhaust primaries and/or a pair of bespoke supercharger cams and/or larger exhaust valves and the distributor might have to go too.

Either/or, the engine and transmission are running better now than they ever have and for the first time I can actually drive it.

With winter looming that'll do for now, I want to attend to some other aspects of the build and enjoy driving it.

glad everything went well mate , should be lots of fun with that low down torque please please done bin it over the winter

i cant see the torque curve at work but hope its lost that big dip it had

Nice one. Enjoy it a bit

It's an awesome drive, with a bang and flame @ 6.1k if I'm late changing up.

Fantastic result!! Now go & have some fun in it to enjoy all your hard work!

It would probably like bigger exhaust valves, not a freer flowing exhaust! Well done David!

Fantastic result!! Now go & have some fun in it to enjoy all your hard work!

Cheers Abz, it drives like a dream.

I now need to focus on sorting out the rats nest of wiring under the carpet in the passenger footwell, get some more air through the pre-rads and lift the front suspension a little.

A good scrubbing up wouldn't hurt it either.

I'll then spend the winter catching up with the list of getroundtoit jobs and collecting components ready to convert to coil on plug and look into cam options ready for next seasons alfresco tinkerings.

It would probably like bigger exhaust valves, not a freer flowing exhaust! Well done David!

Cheers Chris.

As previous post;

The ignition system is nearing its limit so I may as well change to coil on plug and be done with it and I'm reasonably sure that some proper supercharger cams with a lairy exhaust would let it breath to 500 bhp.

Sticking with a "disposable" unopened N/A lump, keeps the cost of an engine failure within a pocket-money budget and a days tinkering, which is my ethos.

10:1 compression with 1.1 bar ambient-temp supercharged boost, has throttle response like a stabbed rat.

Just as my spanners thought they were getting a rest, the idler bearing and/or belt tensioner arm has decided it's time has come.

I inspected the pulleys, belt and timing marks after mapping and it was fine, half a tank of wet roads driving later and it's todgered.

I've seen this trick several times lately, but this is the first time I've seen a belt ride to the back of the pulleys, have a look at yours just in case.

2hp until your kicking my ass.

probably 2 minutes before ive spooled my power! lucky, lucky guy! great setup to have usable power. can't wait to have a drive!

2hp until your kicking my ass.

 

probably 2 minutes before ive spooled my power! lucky, lucky guy! great setup to have usable power. can't wait to have a drive!

It's a Fulcrum Moment, from Total Nutter to Lucky Lucky Guy.

The best smiley I could find for a "Condor Moment".

I'm not satisfied with the dwell angle parameters, maybe there's a few more horses to be let out yet?

The ignition system dwell-angle conundrum beat all at AEM and MSD, so I've poked around in the program and found a Wizard, pick, click and save, simples.

The dwell-angle is now where it should be and without disturbing the timing map.

The mysterious ting-ting @ tickover is cured, the hesitancy at light throttle between 3-4k rpm is cleaned up and there's more power sooner.

I haven't tasked it, or driven higher in the rev range because of the dying cam-belt, the only time it has moved was to fetch the new belt.

After that's sorted, I'll have the mapped touched up.

I've reloaded the parameters with the ting-ting, that's where it's running best until remap and for the record, today I managed one run at Santa Pod.

I was even ready this time.

I ran with the water/meth and was going to run the second without it but with only 4 more pairs to go, my plan was thwarted first by the Official lunch break and then the weather.

It's a strange surface for cold road tyres and I gave it too many beans in 1st, a dry pub was better than another soaking for a ticket and happy to believe James who reports it was 14.1.

I've been and had a good play with the dwell angle, but the bottom line is; there's not enough spark for the boost.

After looking into converting to coil packs, I find that the T.T. 6-set won't fit under the charge-cooler, so looked some more and found that the VVTI packs will fit and is a better system to use with the AEM.

Then went to the "For Sale" page and found these.

The VVTi system is lousy, it's wasted spark and not a patch on true coil on plug. You do know that you can remote mount the coils or coil packs and feed each plug with a normal (but decent) plug lead? That is the better option, by far, assuming the AEM can work something as radically advanced as coil on plug In fact remote mounting the coils is in some ways better as it removes them from the pretty serious eat of the plug wells.

The information quoted below reckons the 6-packs don't like wasted-spark and need an ignition booster to try and make up the shortfall, however, the 3-packs are designed to work with wasted-spark which suits the AEM V1 and doesn't need a booster.

"TT coils require a DLI in wasted spark (AEM V1), and do not show much advantage even when they are used in sequential operation as some people still run a DLI.

The VVti coils run great with Wasted Spark and there is a reason Toyota switched over most of their cars to wasted spark in the late 90's, mainly reliability, but they also delivered on performance. Even the VVti Supra 2JZGTE runs the same VVti coils as the IS300. The 95 Avalon used to use a TT ignitor and 6 indivudual coilpacks, and was switched in 96 to a wasted spark setup using a DS 62 ignitor. The camry v6 was similarly switched to a wasted spark ignition with the same ignitor. The SC and GS was switched to wasted spark when they got VVti, even the 1jz got them I want to say.

VVti coils are newer, designed better, more reliable, and the spark is good enough for very large amounts of boost, not to mention its easier to check your timing cause there is a plug wire on cylinder 1.

If you read AEM's install instructions for the 30-1100 (supra GTE), they are aware of how bad the stock 6 coils are in wasted spark, it always cracks me up to read this, this is what they suggest:

The installation of the AEM ECU on the Toyota Supra TT converts the ignition system to a wasted spark system. This change in ignition strategy requires reducing the spark plug gap to .025”. With standard spark plugs, the reduction in plug gap may cause poor idle quality unless the mixture is run richer than 12.5:1 AFR and the ignition timing is reduced to 11 degrees BTDC. We have found that the use of the Denso Iridium Power spark plugs (IQ24 or IQ26) eliminates the idle quality issue when using reduced plug gaps. Additionally, these spark plugs have proven to perform exceptionally well when used in moderate to high boost applications.

Do yourself a favor, don't buy a DLI or run 12.5:1 & 11 deg @ idle w/ .025 gap to band aid the problem, buy yourself some vvti coilpacks and a ignitor to match. problem solved."

I'm all geared-up to fit the coil-packs, but there are higher priorities.

Since the manifold rebuild, the rear of the mid-pipe was very low and a liability.

The rear tyres need changing and the geometry needs checking, which dictates that I need to get the front Bilsteins lifted the 20mm needed before then.

Operation sleeping policemen, phase 1.

I didn't take a before pic, but here are cut, wonked and sleeved after, it now hangs flush with the chassis rails and I can gain little more ground clearance at the back by lifting the boxes on shorter rubber mounts.

Needs must and trendy TIG welding logistics, were outweighed by accessibility to a stainless MIG welder next to a 2 post lift.

I'm pleased that job is jobbed before I clonked it and broke the manifold again.

I've over-gunned the w/m jet size with 4 X 0.4mm jets, ideally I need 4 x 0.3mm jets, but 3 x 0.3mm would do.

I also have a selection of larger sizes, none of which are any use to me, these things are £20 + P&P + VAT each.

Anyone want to do some swapping?

I'm waiting on a lathe tool before I can attend to the front lift, so have been tinkering where I can.

I've had a rootle around in the local Motor Factors stockroom and found exhaust rubbers that give another 8mm of ground clearance.

Been chipping away at the rats nest in the footwell, grooming it into looms, three sessions of winding my spine up and it's getting there, I reckon it'll take 3 or 4 more yet.

Managed to get at my Supra Treasures and jig-engine stashed at a pals workshop and the VVTI coils now have a full set of clips and new loom.

The DH61 ignitor is mounted on a modified N/A backplate ready to fit, just the AEM to pin up and the conversion will be ready for a pitstop swap.

Waiting for holder for the tool so you can use a manual lathe with cnc tooling. Will be on it's way soon enough

Cheers Noz.

Looks like I'll be getting on with combing out the footwell rats nest.

Chris Wilson's trinket drawer didn't turn up any 0.3mm jets.

Thanks for looking.

Aquamist are sending me some "spinners" to install inside the jets to slow the flow, I'm hoping these will save buying another set of jets.

I've just turned up a trinket, an MA70-GTE CPS to drive the coil packs, it's tidier than the 2J distributor and almost plug & play.

Using one of these will create space to improve the sky-hook idler bracket too.

(Library pics)

Here are the spinners, fiddly little beggars and not a job to do whilst parked on gravel.

To centrally locate the new spinner, jets have to be assembled whilst upside down and the new spinner is located with an original spinner, fitted back to front.

I've fitted the smallest size to all 4 jets, of which only the post charge-cooler 3 are currently plumbed in.

I'll give it a test, when I'm fortunate to find enough space on a dry road for WOT.

Spinners

Spinners and extraction tool

Inside of original jet

Original configuration (pre charger jet)

With new spinner configuration

Inside of converted jet (special service tool - paper clip)

Photos wont load

All hunky dory in Chrome for me!