2JZ head porting.

[GSRman]

shaweeeeet

[Supercrown]

Hurry up Reaper.

I gotta go to a meeting at 1:30.

I want figures goddamn it.

(it has been run and done this morning-and I know some of the numbers by phone-but it's Reapers place to say what they are.)

[Reaper]

RESULTS IN >>>
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[- Expand the jpegs once they come up as they will display better]

Got to the dyno today, had to dial boost back in to match the previous 23psi. As you can see on the boost overlay it doesn't spike as much as the original dyno run but only about 1psi in it. Both old & new runs settle down to 23 by midpoint.

From my visual checks it looks like spool has dropped nearly 600rpm ie. the historic 1 bar mark was ~3600 and is now ~3000rpm.

Peak power is up by about 30rwkw, previous runs showed a few more points before this graph was taken. Top I saw was about 337rwkw.

Curiously mid-point of power graph is nearly same? - theories? >> as this area maps to peak engine torque approx. therefore engine most efficient, query that maybe engine didn't need porting in this area of engine speed? ie. no major improvements realised here.

Torque! Check out the fucking torque curves. Man, this is the shit I am feeling on the road! This car - once it gets past the street spec high stally (3200 flash speed) and starts to build boost it just starts rampaging. It is one angry, cunt of a car now - fucking lovely! Got on it last night to check boost control was working after the split hose issue and it started wheelspinning at about 110ks. Boost onset and torque delivery are fucking wonderful now, so phat and linear. Little bit savage, not at all light switch, err... just like the V8 thing - all there nice and early, not much waiting at all now. Higher stall speed will help get past any low down doughy sections even more so. Not sure I want that as holding the tyres down already with the footbrake is already a handful. Anyway, the difference in the torque curves says it all - mmmm.... lump it out my sweet, lump it out - mete out that sweet, sweet Supra justice!

NOTE: The orig graph showed 530NM of torque 150kph. For some strange reason today's graphs show the blue torque curve of old as showing near some 750 or so. As you can see todays torque shows it's much lumpier, early, and a skooch higher. I called the dyno op./tuna and he says it's a scaling issue and he can rejig it to match. Regardless you can see that torque is a bit up BUT a hell of a lot earlier - all that area under the redline is such a huge difference on the road.

Would like to thank the following kickarse people who have helped me with this car >> TK - the man who started it all, SuperCrown - road tuner extraordinaire, Troy Boy from MRE - dyno tuna hernia man, ME - I almost busted out an extra nut myself on this!

Phat cams are to come - 268/272 Kelfords with 10mm lift. Stay tuned.

Ta,
GEE

[F|sh]

fucking!

you could take some fuel out of the middle maybe to stop it dipping down a little....

that curve is very nice

[GSRman]

schaweeeet moite

[TK]

10% more power on same boost.
23% quicker spool time - assuming 900rpm idle.
Faster spool ramp rate.
Fuckloads more torque earlier in the rpm range.

Hmm, I think we can safely say it worked rather well...

A quick chat to Reaper on the phone leaves me suspecting he's grinning like the village idiot, on road it is apparently a bit of a monster, completely different car - the graphs don't tell the story of what that extra grunt down low does for the shove in the back.
He's contemplating tyre choice now, they don't seem to want to hang on all that well.

Reaper - remember how I mentioned that you may well find you can crank some more boost into it without the turbo cracking the sads? - by the look of that boost curve another 2-3psi will get that midrange stomping quite a bit harder, turbo should cope ok - it's not working as hard for the 23psi now, 25-26psi will probably put about the same load on the turbo as it had before & due to the split hose before you know the motor can take it without detonation.

Cams is gonna be interesting.

edit - coz I screwed up the % boost time improvement.

TK

[2JZR31]

Awesome results. :D

There old run was running more boost in that low area which would explain less gains in that area.

[Supercrown]

It's a really fun car now. Stalling it up to 3000 with the foot and handbrake and then letting it rip just results massive smoky number 11's.

Having a look at the dip in the midrange of the torque curve I think we need to have a bit more of a fiddle with AFR and timing around there.

Reaper, how much trimming did Troy have to do to the map?

Did he fiddle with the timing at all?

Next job is a good long drive on the freeway out to murray bridge to get all the cruise/transitional throttle stuff nice and refined.

[Reaper]

Yes - very much grinning like the village idiot. This car is totally transformed, gets on it so quick now - thank Christ!

Was talking to TK about how to describe it yesterday and to say it is "VASTLY" different may be a little much. It's not quite like "night & day" difference but pretty bloody close.

Before, down low (engine speed), with no load/unstalled you could physically count "wait for it, wait for it, make rocket go now" and by the time you'd finished "now" the car would be starting to accelerate strongly, finally ffs.

The car now gets to that point of good, strong acceleration in virtually sub-second time. Not instant, but not over a second's wait now - Fuckin' Hoo-Fuckin-Ray!!! What's the point of having it all up top - street drags need to get out of the box and that is exactly what the car does now.

Either way - porting the head/bits with OS valves has been a fucking great idea - car is now very enjoyable to drive on the street w/o always feeling like you have to give fucking notice in advance to take some chump on. Now, even if some cunt does sneak up on you it dussa mada anywhere nearly as much since she gets up and boogies virtually immediately now. I now have it pretty much down low, and up top, AND top is only gonna get better with cams & hi boost!

With a higher street stally it will be even better again but the tyre frying action concerns me a little on that score ie. will need bigger better rubber definately - already running Falken RT615's in 275 @ $450 per rear! Can anyone recommend a good semi? or other for the road w/o going wider - I really don't want to have to run sumpin' stoopid like a 315 BFG etc.

We didn't touch ur map Sean, just run what we brung. I had to get to work so we couldn't fock around for too long, just verification runs, boost tuning WOTs, then into several final (graphing) WOTs.

That curve does look a little funny ie. not as smooth as some in ascent trajectory. I think ur right, does deserve a look see.

[NOW - I've been holding off putting in the AEM ignition amp and HKS Type R FMIC onto this thing. Are there going to be any objections if I do this before cam tests? Engine is now capable of taking hi boost (query run out of fuel?) so I want to enable the supporting gear sooner than later. Club dyno day is only 7 weeks away and I'm scared of a certain GT42R that's currently being assembled].

Will come past tonight TK to show you the actual car in real life! Stay out of the metal filings plz! Cheers mate, call ya later today.

Cheers all,
GEE :D:D

[Reaper]

Spoke to Tony Tony Tone last night.

Depending on budgetary constraints we might be able to get the hi-cam numbers out of this car in about 2-3 weeks to see how the curve really behaves with all the porting and oversizing etc. Look like going with the Kelford 268/272 combo. Naturally we'll be graphing clearances on the stock piston to check interference status. If Kelford engineers are correct should clear by several mil.

I will be adding the amp & FMIC in the interim since I already have those lying around but these are more quality changes than true power adders, although I suspect there will be less pressure drop thro the HKS FMIC so may pick up a psi + there at this level? Amp is really for idle quality and to ensure strong spark at high boost since AEM runs wasted spark ignition.

Sean & I will also be playing with timing in the middle of the map to see if we can get that dip out of the middle too, in addition to getting eco etc.

Cheers,
GEE

[GSRman]

I'm still quite blown away that you got 10% peak power just from porting and oversize valves.. thats an awesome result..

[Billzilla]

I'm still quite blown away that you got 10% peak power just from porting and oversize valves.. thats an awesome result..

I'm not .....

[Supercrown]

I did some more analysis of the numbers.

Average power between 2000 and 6700 rpm increases from 206rwkw to 235rwkw. (14% total increase).

The biggest single point increase is at 3450rpm. Before was 115rwkw, now is 189rwkw. That's a 74rwkw difference (64% increase)
(Keep in mind that although this is due to the turbo making more boost at this point, the only reason it is making the extra boost is the head work.)

Consider also that the new graph was off a road tune that I would have liked at least a couple more hours on-with no attention paid to timing at all. I suspect that with the mods TK made to the chambers that it'll take more timing around peak torque.

All I can say is-Point proven TK, well and truly-well done mate.

(I've graphed this stuff to get the above numbers, so I'll do a laminated copy of this stuff, as well as give you the files so you can have them on hand at the workshop)

[10sec rx7]

I'm not .....

im not either,

the ported heads with over size valves on my ls1 brings the boost on 500rpm quicker and this is with a 1.5 drop in compression!

[TK]