e went to MiddlesexTuning's rolling roadin Northolt to fit andtest the Boost

Graphic fromSuperchips. Its name is

derived from the Boost Graphic'sability to alter boost pressures and,well... it looks like a graphicequaliser. The red lights, slidingbuttons and plastic case werecertainly tacky, but there's someclever thought behind it.

For the purpose of our test, weused the Sierra Cosworth of DaveGuildford at MTC. The first dynorun showed a very standard 205bhpat 6600rpm. We also plotted theboost curve which showed lpsi at2650rpm.It then rose to 6psi at3000rpm and Tpsi at 3100rpm,where it remained until6600rprn.This curve is superbly flat and givesthe Cosworth its continuous power

band. We would now try to matchit with the Boost Graphic.

What Is It?The Boost Graphic is anelectronic boost pressureadjuster and mapping device. Ithas a master slider to setmaximum boost levelwherever you want it; 5psi,30psi, wherever. The masterslider then acts like anadjustable boost setting. Theother seven sliding controlsare calibrated with enginespeed. As the enginereaches the rev bandindicated, you adjust theslider to give a percentage

of the maximum boostselected.

It's an aftermarket version ofwhat Ford spent millionsprogramming into the Cosworth'sECU. It's ideally suited to turbovehicles such as the Renault 5GT,Uno and the Nissan Silvia andCherry, all of which don't havemapped boost. Those cars tend topeak early and boost falls offrapidly,limiting top end power.We aim to fit the Boost Graphic toone of these cars, but first wewanted to prove it against the Fordsystem.

flow fDoes ItWork?The Boost Graphic works byelectrically operating an amal valveto control boost pressure, bleedingoff what isn't needed. Theinstructions suggest it can operatethe standard valve on cars fittedwith such a device. However, a

It looks tackybut actual ly has a lot of potential lorcertain turbo'd cars

special amal valve, called a boostcontrol valve is also supplied withthe fitting kit. This is for vehicleswithout a factory valve orelectronic mapping, such asmentioned previously.

Unlike the Cosworth valve, whichis either open or closed, the boostcontrol valve can be open, closed,or slightly ajar, allowing preciseadjustment.

ittingFirst connect the wires to thecircuit board by disassembling thebox. There are five connectionswhich, taken in order, are aIZYfeed, a tacho supply from the coil,two wires for the amal valve and anearth. The tacho wire allows theunit to calibrate its 500rpmincrements from 2500rpm to5000rpm with a jump to 6000rpm.Although there are two valveconnections the second is for twinturbos only.

Next step is to tell the unit howmany cylinders you have, using acombination of three switches onthe board. Alongside this is thetrim screw to set maximum boost

. . , , -

on the master slider.At this point we encountered

several problems which took hoursto resolve. Initially, the graphicwouldn't operate the Cosworth'samal valve so, afterexperimentation, we fitted theboost control valve supplied. It nowworked but the trim screw gave useither 5psi or 20psi and nothing inbetween. Consulting Superchips,we reversed the wiring on the valveand everything was fine, becoming

The Boost Gnaphic hnings electnonic boostcontnol to tne fikes of Renault bGT and UnoTun[o owner$, as we discouen in the linstof a two part te$t

fully adjustable from 5psi to 20psi

Setting upThe instructions said: "Turn thetrim screw fully anti-clockwise andmove all the sliders to maximum."With an accurate boost gaugemeasuring vacuum, you adjust thetrim to whatever maximum boostvalue is safe for the engine. Wechose 10psi since we wereattempting to match the original

Tpsi boost curve.With the master slider

set at maximum(representing 10psi), we

moved the seven rpmsliders to minimum andproceeded to run througheach 500rpm increment onthe scale. Dave held therevs at 2500rpm, while weadjusted the first slider untilthe boost gauge read 7psi.The engipe was then held at3000rpm and the procedurerepeated. This was done right

up to 6000rpm and a full power runconfirmed the engine was holding/psl.Again it's easy to write but not so

simple in practice. The problem isturbos generate masses of heat andthere's no way of removing iteffectively. The more tests wecarried out, the more heat we had.Over the course of three powerruns we lost 3psi and 15bhp fromprevious settings, and severepinking began to occur. Bear inmind, we were running low boostlevels. To increase performance wemight typically aim for 15psi acrossthe board which would producegreater heat, and dangerousdetonation.

There are two solutions. Firstlv.allow long periods between eachdyno run to cool the engine, or setthe Boost Graphic on the road.This second option needs a verystraight road and could beextremely dangerous while youhold precise engine speeds infourth gear for prolonged periods.

Here's the man that does, f iddling withthe thing to set it up. Hope he knowswhat he's doing

This is thevalve bit,whichcontrols howmuch boostyou get. lt'scontrolled bythe sliders onthe booslgraphic,don't youknow!

GWHICTERMS

COIL NEGATIVE

12v SUPPLY(rGNrTr0N 0N)

Inevitably, the driver mustconcentrate on revs and wouldn'tbe looking where he's going.

The ResultsEventually we programmed theseven rpm sliders to Tpsi but theCosworth was now shagged. Apower run confirmed the BoostGraphic had programmed Tpsifrom 2500-6000rpm. The powercurye showed more bottom endpower since we had Tpsi where theFord programme only allowed

SECONDVALVE FORBI.TURBOS

EARTH

1psi. We lost outslightly in mid rangebut pulled out againto draw level at6600rpm, were werecorded 204bhp.

After a dayunravelling the BoostGraphic we werepleased to achievethese results and arenow confident wecould match theCosworth powercurve almost exactlv.given more practice.But Dave Guildforddidn't feel the systemwas fully exploited onthe Sierra;he wantedto try a Renault 5GTor LJno Turbo to seewhat it could reallydo.

WellCleverThe Boost Graphichas tacky packagingbut is a clever enginemanagement systemwith full control overboost pressures across

the useful rev range. It could be arevelation on vehicles without thisfacility as standard, since it shouldbe possible to overcome inherentproblems at low and high enginespeeds. Essentially we fitted it tothe wrong car, but intend to rectifythat in a future issue.

Dave Guildford was veryenthusiastic about the product. Heclaimed: "I've never seen anythingthat maps boost like that.Itmanipulates the turbo better thananything else. However, we need tofind something with horrible boost

Here's thepower Gurve.With the BoostGraphic we gotmore powerlow down, losta bit in themiddle andgained againat the end. Alair result onlhe day, thelads wil l behappy withthat, Brian

curves, since theCosworth system isjust too clever.Readers will needto use imaginationto see the fullpotential of this boxbecause we haven'tapplied it properly...yet. It's very clever,though."

Although wedidn't fit it properly,the plastic casemust be drilled forthe wires to exit. Asuitable mountingposition must thenbe found. Thedashboard is anobvious locationbut, after several hours on thedyno,I'd be annoyed to havepassengers sliding the buttons andwrecking the mapped boost curve.It would, however, give the driveraccess to adjustable boost, for wetor dry conditions, via the masterslider.

Locating under the bonnetwouldn't be clever since there's nowater-proofing. So the idealsolution calls for mounting withinreach of the driver. awav frompassengers and with therpm slidersdisconnected so that the map can'tbe disturbed. The driver could thencontrol maximum boost by the

BOOSTCONTROT

) ATMOSPHERE OR

master slider. Unfortunately, thisfacility is not available, so bewareof passengers attempting todetonate your engine.

As for cost, the Boost Graphic isf2T6tncluding VAT fromSuperchips' dealers, such asMiddlesex Tuning. On top of thatyou should allow for fitting androlling road costs. MBP

z1.g

t:fs

l?'n

158

13a

116

9B

?g

5E

38

10