Reveiews - Manifold spacer, TB and Chip

[Tsunamix]

Hi Folkses.

First a word of warning - do NOT build the same engine combo I have, unless you have also improved your suspension. This is a serious word of warning. Theres a combination of circumstances and action that would catch a novice by surprise and cause heartache if not grief. Read on for the details but be warned - suspension improvements are NECESSARY for safety from here in.

I drive a VT2 1999 ecotec six, auto. 18 months ago I put a set of MACE 1.98 rockers on it, then a cheap sports exhaust. then I added King spring Low's (not super low), Boges gas sports struts and shocks, 32mm front sway bar, 22mm rear, full nolathane bushes all round, new factory hydraulic engine mounts, slotted brake rotors all round, GSL's police spec pad's, and run on 235/45 R17 Falken FK452's.

Everythings been chosen rather carefully. The Falken's are a wheels tyre test winner, the Boges brand is used by BMW and Mercedes as factory items, and so on. I spent my money on the suspension and brakes before doing much else.

Next was a gearbox rebuild with a beast stally and bands - factory RPM on the stall. Beast do carbon fibre bands so they should last a while. A transgo stage 2 shift kit and corvette servo piston were added. Drives wonderfully. The beast stally locks up solidly, there is no give in it. So if you get up it, it amost feels like an extra gear change when it locks up.

Now for the new additions. A MACE under plenum 12mm spacer, and oversive throttlebody and a chip.

Of course, being a something of a perfectionist I din't read the instructions - I can't read them unless there in swedish or chinese anyway, and since MACE is Australian they were usless too me. Actually they were dead simple. There is only one point to remeber about installing all 3 pieces - the blanking bplug goes into the vacuum hose with the elbow at the throttlebody.

Easy enough really. strip off the plenum, taking care not to drop sh*t down the runners. Leave the injectors clipped to the fuel rail, just remove the wire clamp that holds the black elecrical connectors on. Remove the fuel rail and injectors and remount with the spacer bolts.

Clean the lower plenum face in the valley, and add a very thin skin of sensor safe silastic - conveniently supplied by MACE with spacer kit. More is definitley NOT better. use this thin skin to tack the spacer in place. Clean the sensor o rings and add a little bit of reassembly lube. Like the Penrite one I had left over from MACE's rockers. Clean the mating face of the plenum and add a very thin skin of silastic. Do NOT fill the vent channels between the O-rings. Gently replace plenum in position. Gently wiggle the injectors until they are all seated properley. Remove the factory plenum mount bolts and replace them with the (Grade 8.8 High Tensile!) bolts supplied. Finger tighten them. wiggle everything to make sure its seated. this is important - stuffing an injector o-ring will make vaccum leaks. Tighten and refit everything.

Throttlebody - be careful of the plastic clip that holds the cruise control cable onto the nipple pin. It's often dead due to heat aging.

removing and refitting the new throttlebody was dead simple. Read the instructions that I didn't read and it's even easier.

Mount the mace chip. Have a torx bit screwdriver handy :P

Disconnect battery for 30 seconds. Reconnect, start the engine, hold at 2000 rpm for 2 minutes. stop engine and restart. Should be good to go.

I found that somewhere along the line, the exhaust gas recirculation pipe fitting had deformed the pipe and I was getting an vaccum leak into the manifold, behind the throttlebody. Made for a slightly insonsistent idle. I removed the recic ipe and blanked it off with a 20c piece and some silastic. I also clamped (flattened and bent double) the end of the recirc pipe until I can get a new one. This pipe is thin and could be bent with tweezers.

Problem solved - but this basically makes the engine illegal as it would fail emissions test. Since today's sunday I will have to get a new one on Monday from Holden.

Ran the engine at idle for a while to get a little heat into the engine, a dribbled a little sewing machine idle on the injector seats to make sure there were no more vacuum leaks (it will drink the oil if there is).

I noticed without the recirc attached, and the spacer in place, that the plenum temp was stone cold (air temp) even with the engine at operating temp.

Jumped in and went for a drive. I drove from Strathpine to Samford and back (northern edge of Brisbane). Winding twisty hilly roads, speed limit of 80 mostly. 20 minutes out, stop and check everything (plenum still stone cold) and came back. Got home, checked everything out again and this is my thoughts :-

Plenum was still stone cold !!!!!! after the run (about 45Km all up plus stuffing around) I was leaning on the plenum checking my handiwork on the 20c piece and it was genuinley cool to the touch.

Important point - On cruise control, the shift pattern for the auto was aggresive. I don't know if thats's part of the memcal programming. Several times it surprised me by changing down 2 gears instead of one, and giving it a solid rev. up to about 3500rpm (This happened on hills, and the road was twisting as well as climbing) . In the wet, that would have broken traction. Part of the issue is undoubtledy related to the stall convertors torque multiplying effect, but unless your suspension is sorted, I could imagine it throwing you sideways a bit in a single wheeler diff equipped car, in the wet. If the Memcal has something to do with shift points, then between it and the way I have built my gearbox, it's too aggressive for the cruise control.

There is definitley a boost to low down torque. it will catch you by surprise the first time you touch toe to accelerator. I have a loose draw in the dash under the stereo which used to occasionally come out under hard acceleration. Now it's every time I come off the mark.

I think economy may be improving with it. You certainly need smaller throttle openings to achieve the saem acceleration. The electronics are telling me that I will get 720 Clicks to the tank if I keep driving that way - which was not all that gentle. Let's wait and see.

the car had a best quarter mile time of 15.72 before today. 3 runs gave me a 15.32, a 15.48 and a 15.44. Solid. This is tested with my iphone's in built accelerometer and a dyno progeam, so It's probably not exact, but i think it's a decent indicator.

Driving normally, you notice more low down torque, but the build in the higher rev's you get is less pronounced. This is because there is less difference now between lower end acceleration and the mid/high range the ecotec has.

It's a decent nett gain in my books. With the advantage of improved driveability as it's not as sluggish down low, and a large improvement in consistency as the plenum air temp has to be more consistent.

I spent less than $500 bucks, and maybe 2 hours getting my hands dirty for an improvement. I get the feeling that now the factory cat is holding me back a bit (I have extractors and a 2.25" sports system), so I think that I will keep the extractors and switch to a 3" with a bullet cat. Yes it's big for a Naturally aspirated system, but I plan to raptor it and it will be fine for that.

In general - its good value.

[MACE]

Wow! Thanks for the constructive feedback Tsunamix

Very my appreciated for taking the time out to write up this very detailed and informative review.

I supposes it's a good time to remind people, as we normally do, to be initially cautious when testing out new performance products. As no matter how "simple' they may appear on face value, they can certainly have an impact on driving characteristics, whether it be in increase of power or power delivery etc.

Cheers
Steve

[greenfoam]

.3 gain from a insulator/spacer, throttle and tune on a VT S2 is pretty impressive, would be fair to say .1 from each I guess, maybe a bit more from the insulator and tune than the throttle but anytime you can gain .1 on a V6 is a good time, it's not easy

[vxcalais_01]

Mace you supply tunes to some models as well ? Excellent writup Tsunamix !

[immortality]

good write up mate. good results. i think a tune will do wonders for any V6 especially if it inculdes re-mapping the gearbox shift points as the factory seting are poor to say the least.

in regards to the EGR valve, this isn't fitted to the VS ecotecs but was fitted from VT onwards. it certainly is a major contributor to manifold heat. Tim @ raptor does a special "EGR valve gasket support plate" which as you have discovered makes a huge difference to manifold temps.

[Raptorsc]

Yes, the EGR does need "supporting" better in order to provide stronger engine performance

[MACE]

Mace you supply tunes to some models as well ? Excellent writup Tsunamix !

We can supply mail order tunes on pretty much all commodore models, from various tuners across the country

In regards to blocking of the EGR valve it definitely does reduce the inlet temps, however the main reason why these manifold insulators work so well is that they increase the runner length.

Cheers
Steve

[Tsunamix]

After a couple of weeks of driving I have decided to stick with the MACE chip that came with the TB. I had some issues with a sticky throttle. After dropping out the bronze bushes and soaking them in a mix of CRC and engine oil overnight, the stickiness in the throttle has gone away.

Under the factory tune, especially in normal mode, the response to the throttle at idle is too harsh. Quite hard to be smooth at low speeds. The MACE tune puts the driveability back in down low.

I don't think it's a performance tune though, it feels the same at WOT with both, and I recorded near identical times with both.

[MACE]

After a couple of weeks of driving I have decided to stick with the MACE chip that came with the TB. I had some issues with a sticky throttle. After dropping out the bronze bushes and soaking them in a mix of CRC and engine oil overnight, the stickiness in the throttle has gone away.

Under the factory tune, especially in normal mode, the response to the throttle at idle is too harsh. Quite hard to be smooth at low speeds. The MACE tune puts the driveability back in down low.

I don't think it's a performance tune though, it feels the same at WOT with both, and I recorded near identical times with both.

I'm glad to hear that you've sorted our your issues with the throttle body, and if the problem persists we're more then happy to replace it for you. On this note however it's best for customers to contact us if they have any problems with our products As in the past some customers have made matters worse by trying to rectify problems themselves, without even the slightest bit of our input

The tune you have is a generic bolt on tune. In which case you may be at the limit in regards to the amount of bolt ons that it can tolerate, or they're may be another underlying issue (dirty MAF?). In saying this though how do you find the fuel economy now (before and after the memcal)?

Cheers
Steve

[Tsunamix]

Can't really compare the economy as yet - as before i did the upgrades I had a working EGR, and I butcher'd the EGR pipe during the install, and I haven't yet got around to replacing it.

Not exactly laziness - Moving house - Get the keys next Monday so I've been in the shed boxing crap up mostly.

My driving is all city driving, and my economy has been crap for a while. As it stands, I get 8-9 K to the litre city cycle. It's crap.

I have a few ideas on the back burner, Although I'm not sure what I will do about the EGR. I might forget it and hope it goes away. At the new house I finally have a decent workshop again, so I'm thinking about getting a second hand Intake upper and lower, another spacer (maybe 25mm this time) and sitting down with the die grinder and sanding wheel to see what I can see.

I have weird ideas about fitting an extension pipe Inside the plenum, to increase inlet tract length. Might be viable. If nothing else I will do a full port match and relieve, open up the area behind the TB, and do something about the ends of the inlet runners (in the plenum). Maybe even get some second hand heads and go to town. I've been itching to try a pocket port on a v6.

Meh. before or after I invent a time machine.

By the way - MAF should be Clean, i cleaned about 6 weeks ago. I might be at the limit of a few other bits and pieces though. Still running a factory Catalytic converter for instance. I know there ok but with the changes I've made who knows.

[vxcalais_01]

8-9k's per litre is crap ? What re you expecting, thats Corolla figures...........

[MACE]

I have a few ideas on the back burner, Although I'm not sure what I will do about the EGR. I might forget it and hope it goes away. At the new house I finally have a decent workshop again, so I'm thinking about getting a second hand Intake upper and lower, another spacer (maybe 25mm this time) and sitting down with the die grinder and sanding wheel to see what I can see.

Keep the EGR, and modify it that it's more active to improve fuel economy

I have weird ideas about fitting an extension pipe Inside the plenum, to increase inlet tract length. Might be viable. If nothing else I will do a full port match and relieve, open up the area behind the TB, and do something about the ends of the inlet runners (in the plenum). Maybe even get some second hand heads and go to town. I've been itching to try a pocket port on a v6.

I like that idea, of fitting extension pipes inside the manifold

[MACE]

8-9k's per litre is crap ? What re you expecting, thats Corolla figures...........

Agreed! You're getting good fuel economy as it is! Wish I could ever get that sort of economy out of my V6

[Tsunamix]

Huh ? I was getting 9-10 to the litre doing mostly highway driving - 60-100 kph when I worked brisbane southside. Drove 120 km a day and would get 5 + days out of a tank.

Driving to Gladstone from Brisbane (550Km one way pure highway, evening / night driving) I would routinely top 750 a tank. You don't have it bacwarkds do you - 8.5 / L is 11.8L per 100km . Not great at all.

Around the city I'm getting 480 - 520 out of about 63 litres

[immortality]

Keep the EGR, and modify it that it's more active to improve fuel economy



I like that idea, of fitting extension pipes inside the manifold

try using some of that steel putty stuff. you can mold it and it hardens like steel. this way you can make some nice trumpets and get atleast another 25mm on your runner lenghts

[vxcalais_01]

You said 9 litres per 100ks for city driving, you confused the hell out of me now hehe.........

[immortality]

Agreed! You're getting good fuel economy as it is! Wish I could ever get that sort of economy out of my V6

best i ever got on a long trip (100km's +) was 6.8ltr/100km's. on my last open road trip i averaged 10/100km's and there was some serious touring going on. Rotorua to Auck in 2 hrs. the same trip would normally take 3hrs +

VN with bolt ons and a decent Tune (my tune) goes fairly good. even with 3.45 gears in the ass

[Tsunamix]

You said 9 litres per 100ks for city driving, you confused the hell out of me now hehe.........

Nah I said 8-9 to the LITRE

[Tsunamix]

Got a better idea than putty.

The plenum is almost 1.5" thick around the ports for the intake runners. Going to machine that down from the inside to about 3/4" thick, in a rectangular 'plug' . Then I'm going to get some 10mm SS304 plate and get it laser cut to match the pattern of the runner end. Tack weld some SS pipe onto the plate and bolt it in. hey presto - trumpets. Then i can have the fun job of playing with trumpet shape and length, maybe even bending them towards the walls of the plenum then cutting the trumpet end at and angle back in towards the center of the plenum.

Anyone care to donate some machining skills and some dyno time ? I have the fluid dynamics and engineering ability to design and proto flow the trumpets, but I don't have much of a workshop.

Keep your cottin pickin fingers off this idea Greg it's my precious !

[Tsunamix]

Update.

Got a few minutes peace and quiet in the 110 Zone up the coast last night to run a few 0-100 times.

Best Run

60 foot 2.49
100m 6.43
200m 9.66 @125.54
0-100KPH 6.64
Equates to 145 RWKW at a 1550KG base weight for VT and allowing 200KG for driver and fuel, and crap (not over generous - I weigh over 140KG myself).

worst run
60 foot 2.52
100m 6.57
200m 9.87 @ 118.99
100KPH 7.04 seconds


i guess it's ok for now.

[immortality]

measured how? the VT is a slug, the 0-100km/h seem a bit quick. even with a few mods

[Tsunamix]

Same old same old. Apple Iphone and PocketDyno Software. I make no claims on it being accurate

proabably more than just a few mods now. Full exhaust & extractors. Totally reworked auto box. 1.98 rockers, manifold spacer, TB, CAI, Chip to suit TB (not a performance tune).

More to come too. Rework the exhaust to a 3" single, 3.7 diff and a Raptor V. As the budget allows. (yeah right)

[immortality]

Same old same old. Apple Iphone and PocketDyno Software. I make no claims on it being accurate

proabably more than just a few mods now. Full exhaust & extractors. Totally reworked auto box. 1.98 rockers, manifold spacer, TB, CAI, Chip to suit TB (not a performance tune).

More to come too. Rework the exhaust to a 3" single, 3.7 diff and a Raptor V. As the budget allows. (yeah right)

i was just looking at the 60foot times. i'm doing 2.3sec 60 foot times to get 15.2 sec 1/4 mile times on Gtech. 6.8sec 0-60 times. i'm doing it with a manual so it's harder to get it moving then with a auto. i had bad wheel spin right through 1st gear. must try it on my new tyres when i get my vac leak fixed. with a slow 60ft time it makes it very hard to get a high MPH or KM/H unless you have bulk power to getthat top end speed up. in general, if you can drop .1 from your 60ft time, yo uwill drop .2 for the full 1/4run.

[Tsunamix]

Hmm.. Fair calls.

I do run 235/45 Falken Fk452's which are sticky as all hell. On my best run I got the tiniest bit of wheelspin - more likely dust on the road than anything else. Wheelspin is never an issue for me. Manual selecting gears right at the cutout works best - I get the tiniest bit of wheelspin into second - more often than not accompanied by a bit of belt slip.

The VT goes pretty hard from about 3500 up.

I think the 'box plays a big part. Carbon fibre bands, beast stally, stage 2 shift kit and corvette servo means the changes are fast.

I have run worse times than the ones above I just dont share em with you :P

[immortality]

that was on my old setup with only 14 inch factory stock wheels with the shittiest 195/70/14 as a poor excuse for tyres. no doubt my current setup is faster but i don't want to kill my suspect clutch until it's time for replacement. i now have accelera 234/45/17's on and traction is 100% better