JET951

Yesterday , Eastern Creek ( Sydney Motorsport Park )GP Circuit , NSW Australia , Porsche Club NSW SuperSprint No 1 for the year
Weather conditions , normal for February , humid and warm to hot partly overcast , high track temps but not excessive

Good turn out with some 70 or so Porsche's & thankfully ( to my knowledge ) no cars damaged by accidents ( hitting barriers etc ) , just the usual spin offs with little damage

It was good to see Patrick Garvan & Paul McKinnon there with Pat's 944 Turbo Time Attack car , but unfortunately the 951 got a misfire after just a few laps in the warm up in the morning , possibly a lash cap had come off( very modified head ) , but will find out more this week etc

Sean Buchanan had put together a 3.0L 8 V engine for Mark Bloxham (this is for Mark's "Mexico Blue" 1986 951 , naturally this was a 2.7 944 engine ( Mark purchased this 2.7L engine 2nd hand) that Sean dismantled & rebuilt with custom Wossner pistons & custom rods & a 2nd hand 3.0L crank , but apart from pistons & rods etc & the metal had gasket it was all original 2.7 parts internally , meaning standard cam , valves & springs etc etc , we even use new standard 944 plastic oil baffle ( no dry sump ) & we just use the same crankcase vent system Sean made for the 2.5L engine the car previously had
Externally the engine received some very trick exhaust headers & X under Pipe that Paul McKinnon fabricated ( Evolution Motorsports, Sydney ) to mount up to the Vitesse Stage 5 turbo

Sean assembled the engine & then doing some calculations , made some mounting brackets to mount the R/H/D steering shaft onto the engine itself , so when Paul had the assembled engine he knew where to build the headers around the steering shaft ( nice idea Sean ) so when finished the R/H/D steering shaft fitted perfectly when the engine went into the car
The engine also received a nice custom alloy inlet manifold & throttle body & naturally , like Sean's Twin Cam 16V 3.0L engine , Mark's car also runs E 85 fuel

So yesterday was the first day at the track for Mark's 3.0L 8V , Sean had finished off the air fuel ratios on the dyno a week before this was its first shake down test

It was great to see both Mark in his Mexico Blue 3.0L 951 & Sean in his Black 3.0L 951 getting faster and faster during the early track sessions , they were both in the same speed group ( speed group 1 ) with most of the GT3's , be it full race GT3's on slick tyres or "R" specs , it all depends on the owners / drivers what class they want to be in , in the case of Sean & Mark they are in Class 1 = road legal "R" spec tyres are required , where as Open Class( proper race cars) = Slick race tyres are required , then below class 1 , there is class 2 , 3 , 4 , 5 , 6 etc ,all power to weight ratio classes

Sean in his 951 was being shadowed by Mark in his 951 , so when Sean overtook another 911 ( usually a GT3) Mark would normally follow suite when possible & it was also interesting to watch both cars as Sean's 951 weighs quite a bit more than Marks 951 , but they have similar suspension ( MCS ) and same gear ratios & same 4 plate motorsport diffs & particularly how their engines respond as Sean's is a twin cam 16V 3.0L & Mark's is a 8V 3.0L and both on the same E85 & both running Vitesse Stage V

Sean did a PB ( personal Best ) time for the circuit ( for "R" specs ) on the day & I think Mark would have done the same , Sean won Class 1 for the day & I think he came in 4th outright in the line up of fastest Porsche's there on the day & I am fairly sure Sean's 951 was the quickest road registered Porsche on the day that drives to work 6 days a week ( commuting Porsche ) & both Sean & Mark drove to the circuit with their "R" spec tyres on the car , none of the lets swap the wheels and tyre on the day , nope, drive there , put the track suite & helmet on & go racing in a 30 year old Porsche , that is not meant to be up at the pointy end of outright results against the latest GT3's ( quite amusing actually )

Here is a quick list of the next 15 Porsche's that came in behind Sean's 951 ( best lap time)

GT3
991GT3
991GT3 3.8
Marks 3.0 951
996GT3
991GT3
997GT3
991GT3
981 Cayman
911 RSR Replica
996GT3
991CS
Cayman GT4
Cayman Comp
911 RSR Replica

I will get Sean to put up some photos in the next two days & Sean may have some in car video footage to put up as well

Many Thanks to all the volunteers who turned up yesterday to help out & a big thanks to John Vitesse for his fantastic stage V

Regards
Bruce Buchanan
Buchanan Automotive

944crazy

Nice work guys...I was having a look on natsoft and those are two very quick 951's indeed! Wish I was down your way so I could see them in action.

blade7

Nice write up, and a little surprising although lighter the 8v 3.0 kept the 16v 3.0 in sight.

JET951

There is around 170 - 200 Kg difference in weight between the two 951's , Sean's 951 is mainly a drive to work car & has all the comfort things you need in a car you drive every day , like ]

Full sound insulation everywhere & full standard carpets , even rear seat belts and the base of the rear seats

4 speaker sound system & head unit & full electric ( last century ) auto aerial

Full ( standard glass ) no plastic windows ( Marks 951 has a lightweight rear plastic window)

Standard electric windows ( Marks has the 968 CS type ) manual wind up windows

Sean's engine weighs a bit more , the twin cam head + the twin cams / 16 valve set up weighs a bit more than the reasonably light weight 8V head

Sean's 951 has the standard sunroof ( the fibre glass removable roof weighs a ton )with all the standard electric bits to make it work ( motor & trans / cables etc etc ), Marks car has a non sunroof panel

Sean's only weight saving item is the single skin carbon bonnet ( front lid ) he made himself , so that saved about 20 KG , but we had to add 4 ( four ) bonnet catches and their fabricated steel brackets , so that put back on about 5 to 7 Kg , Sean's 951 weighed in about two years ago at 1375KG , she maybe 1360 KG now , she is no lightweight , because she is a road car with A/C and the works & Sean's car ( like Marks 951) has heavier front brakes than the small standard 1986 ones & Sean's car runs at the track larger heavier( read inexpensive ) wheels than the standard little dia lightweights the 1986 one had as a road car , this all adds weight & for the track that is not good

We think ( we have not yet compared back to back dyno comparisons ) that Sean's twin cam 16V may produce more possible power up top , but the 8V feels more powerful at lower revs , meaning she will produce more torque coming out of corners , but then again the 8V can be adjusted to produce even more power up top , but its that quick now I think she is close to perfect

The one thing I haven't mentioned is that neither of these cars run a dry sump , we never have , but we run quite good crankcase ventilation & large oil coolers , but more important than that is the need for oil film strength & these engines need very high oil film strength engine oils , so for years and years we run high ZDDP racing oils that are higher than 25W-60 in viscosity , read into that what you will , and do not think we run full 20 lap races , we do not , these engines are designed for the club events , say 3 to 4 laps flat out , because by then the owner is completely exhausted and wants to come in anyway , remember these are high output club event cars that have to be flexible & easy to drive & can be maintained without a team of guys for each car ( like the 996/997 GT3RSR )

Sean built his 3.0L 16V E85 engine about 4 years ago ( I think ) and we just do periodic maintenance to it , like oil changes after every event , cam belt / rollers every year , new metal head last about every 1.5 years , we have even removed the sump about 1.5 years into the competition events to inspect the big end bearings ( conrod bearings ) and they were like new , even the bores are like new ( head gasket change time ) , and why is this so }

Answer } Engine Oil Film Strength & last century Porsche engines run hand in hand , I have picked up a few hints in the last 39 years working on Porsche sports cars 6 days a week

Regards
Bruce Buchanan
Buchanan Automotive

blade7

Does Sean run the 25w-60 oil for road use, and is your crank ventilation and oil cooler setup common knowledge?

JET951

Yes , Sean runs the 25W-60 ( + extra ) all year round , remember our climate is mild in winter & hot in summer
Crankcase ventilation is nothing unusual , just a good set up that we like to use & make ourselves , but I stress , its not groundbreaking , like all things that work , its quite straight forward

Oil cooler is a 963 / 993 oil cooler & we simply remove the fog / driving lamp on the track day to give the much bigger oil cooler more air through the hole we cut behind the fog/driving lamp & at the end of the track day we just put it back in ( takes less than 3 minutes )

All very simple stuff , we are not trying to reinvent the wheel , just make the wheel go faster & reliably

And as the saying goes "results talk for themselves " , Sean has in his 1986 951 ( since 2006 ) has won the PCNSW Drivers Championship 4 times( maybe more I couldn't be bothered to look it up ) & the Motorkhana Championship 5 times( I remembered that one ) & the Supersprint Championship once , reliability plays a big part of winning championships ( Major Part )& the correct engine oil viscosity /oil film strength is that MAJOR part

Regards
Bruce Buchanan
Buchanan Automotive

ab54666

Very interesting, for someone who is about to embark on building a 3.0l 8v engine for my 968 it's good to hear of such power and reliability.

blade7

Any issues mounting the 993 cooler, I was told it's a fair bit bigger than the standard one. Also is your crankcase ventilation set up plumbed back into the intake ?

Paul.

964-C2

Thanks for the write up. Very impressive!
Detailed information of the crankcase breather system would be very interesting...
What boost pressure are theese two 951's running?
Thanks.

74goldtarga

Sounds like a great day. Encouraging that you are getting good performance and reliability and competing with newer GT3s.

What oil do you use specifically? I have been using Millers nano drive.

What level do you fill the oil? - I have been told by a very experienced builder / professional mechanic and shop owner / track record holder in 944/951 to fill the oil above the top mark at all times - was told this after I lost my last engine. With my last engine I would half fill the catch can when I had the oil at this level but I ended up losing the engine due to rod bearing failure with the oil at a lower level.

JET951

Hi Paul , to fit the 993 / 964 oil cooler , you have to reposition the power steering oil cooler ( we mount a slim one else where ) , we install the smaller washer tank without headlight washers ( 944 628 060 00 ) & some cutting is needed in where the larger oil cooler will go & we fabricate all the securing bracket & we modify a new oil pipe ( 951 207 112 02 ) cut , bend & re-weld to get a good position & new oil hoses

And yes the crankcase ventilation is finally plumbed back into the air intake

The thing we find important is we make a custom catch can mounted as high as possible with two large dia hoses breathing into it ( one from the standard breather bottle ( but opened up more ) & the other from top of the twin cam cam cover ( 16V ) or the cam box (8V )

Regards
Bruce Buchanan
Buchanan Automotive

JET951

Hi 74Goldtarga , we have been using for years and years the very inexpensive readily available Valvoline Racing 25W-60 engine oil , plus ( you will love this bit ) we also install a good old fashioned ( a bit like me ) USA made product that really works and has been around for 50 odd years + ( STP Blue ) , meaning the STP that comes in the Blue plastic bottle 15 FL OZ bottle

We use 1 bottle per 4 litres of Valvoline racing engine oil , very important ( for us ) to keep the engine oil temp to below 115 Deg Cel , hence why we run a in car oil temp gauge , very basic , but its a good quick reference point for us to see quickly

Remember , this is ideal for us with what we do , meaning 3 , 4 or 5 laps ( flat out ) and then we are in for 30 - 40 minutes + ( pits ) resting and waiting for the next session

The combination of the very honest Valvoline Racing ( in Australia ) its 25w-60 & the STP , thats been around as long as I have been on the earth works well , in fact very well

Regards
Bruce Buchanan
Buchanan Automotive

pole position

The 25-60 must be a down under Valvoline offering. Redline and Motul make a 20-60 which are available in the US.

George D

Glad the event went without issues. Thanks for the informative post Bruce - sharing your and Sean's cars. Neat these "underachievers" continue to prove Porsche engineering mandates back when these cars were designed. Today there isn't a high end auto manufacturer not offering small displacement engines with forced induction in even their top tier platforms.

The Lincoln Continental in the USA with a 2.0 inline 4 is selling well here in the US. There are a few Ford engineers from back in the day, in your part of the world, designing well designed - turbo engines. The Sierra has been a dedicated racing Ford product for decades outside of the US.

Regards,

G

JET951

Hi 964-C2 , Sean runs 22 PSI boost pressure & we think the Mexico Blue ( Marks 951 ) was on 19 or 20 PSI , with a lot more potential yet

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Many thanks for you're comments George , you have a similar opinion to me in regards to what manufactures did & could do and what they do to survive today

Regards
Bruce Buchanan