after cracking another AA 94mm barrel on Bens last dyno session , we have decided to step it up a notch and purchase some better quality heads & barrels for his supercharged engine .
In our experiences on both Chris Bolton and Ben Fords' race engines we have found that the AA barrels are very reliable / suitable for up to 250hp . Once both engines exceeded this level of performance ( Chris 305hp @ the wheels and Ben 310hp @ the wheels ) we have had issues with the AA barrels splitting down the top spigot , normally resulting in cylinder head damage also .
Bens new 910 Autocraft cylinder heads have arrived !! Titanium valves 50x39 & K800 springs . Ben wont use the Autocraft 1.4 rockers that came with the heads as we will stay with his Pauter billet 1.4 roller rockers
Bens new raceware headstud kit has arrived and also his new Pauter semi-modular 94mm cylinders . These cylinders have a large flat seating surface to the cylinder head which will keep the cylinders a lot more stable under high cylinder pressure and a far better seal with the 0.060" copper head gaskets and 6-stud configuration .
Bens Autocraft 910 heads will undergo quite a bit of machining to accept the new cylinders , which will entail removal of all cooling fins down to the sealing surface .
Bens new Pauter semi-modular cylinders are fitted to his engine to check clearances & all OK .... Ben installs the microtec ECU & loom , now he starts the wiring to the sensors & throttle body .
We fabricate some flange plates for Bens 910 Autocraft heads and the flange plate ports are machined to the size that we want his intake ports on the heads . I will match-port the heads after I have finished Chris Boltons' engine
Tonight we polished the ports in Bens' Autocraft heads , then attacked them with the milling machine to cut them down to suit the semi-modular Pauter barrels
Interesting port design, whats your rationale behind siamesing the ports like that rather than keeping them individual? Certainly out of the box thinking.
hypo-vwAustralias 1st 10sec street beetle (Jan 2007) 10.49secs@132m
Bens barrels are bolted to his heads with the 5th & 6th smaller studs , then are located onto the headstuds to check alignment prior to drilling the cylinder heads for type-1 stud pattern
Ben removes his engine & transmission last night to install his new aluminum spool
last night was transmission night at WPVW . Ben removed his transmission so that I could install his new aluminum spool . After many passes over the past 4 years the ring & pinion still look great .
The new aluminum spool & chromoly drive flanges gives Ben a bit more piece of mind that the transmission will cope with the added power he is searching for from his supercharged engine
LIFE IN THE LOW LANE wrote:What brand of spool did you go with Wayne?
Ben purchased his new aluminum spool from Rancho Transmissions in USA . It is an 091 2-litre style , which required the replacement of all associated diff parts (except the crownwheel) to fit into the 002 transmission
tonight Ben installed his transmission & connected everything at the rear of his bug , he finished the wiring for the Microtech EFI , then he fabricated new flange plates from aluminum as that is what we will fabricate his new plenums from
I bolt Bens new Pauter barrels to his cylinder heads , align them with the headstuds in the engine case , then tighten them in position so that I can drill the heads to type-1 stud pattern as the Autocraft pattern has approx 2mm further stud spread pattern on each stud . I use the barrels as a guide to ensure correct alignment . To do this Allan extends & machines a new drill bit for me .
After the heads are drilled I find that No.3 barrel has to be clearanced on the fins to clear the engine case .
After the barrels are clearanced and installed I find the cylinder head gaskets need to be hand-filed to elongate the stud holes for the smaller 5th & 6th studs .
Bens' Autocraft heads are prepared & assembled . The pistons are installed into the new cylinders , the cylinders are painted & the top end is assembled
today we started to fabricate the plenums for Bens' engine & Morgan was kind enough to come and glue them together for us with the TIG .
Bens' engine will be finished & installed tomorrow
I shim the Pauter rocker assemblies to offset the exhaust rockers to suit the 910 Autocraft heads and find that I have to replace Bens pushrod tubes also with wide-mouth tubes to ensure that the pushrods don't rub on the tubes
next problem was Bens pushrods are way too short for his new head & cylinder comination . We contact everyone reputable that we know to try & find a set of really long pushrods (296mm) with no luck at all . We send Chris Bolton to CBB as Mike has a long set of pushrods , but we find that they are 4mm too short !! (thanks for your assistance Mike)
So we send Bens parents to Sydney Thursday morning to purchase & collect 3mtr of 3/8" chromoly thickwall tube & to collect a 205ltr drum of methanol . They took Chris Boltons T4 transporter , after collecting the fuel & the tube they are on their way back to WPVW when they break down at 3pm in Liverpool (Sydney) . An hour later we organise a tow truck to go to Liverpool to collect them & the transporter . At 7-30pm they arrive at WPVW , the transporters alternator decided to stop working & the old battery failed !!
I cut the chromoly tube into lengths & Allan picks them up , takes them to his machine shed & makes the new set of pushrods for Bens engine .
Chris Bolton starts to fabricate fuel hoses for Bens new Boss EFI
Friday morning the battery is changed and the alternator has new brushes installed , the transporter is alive again.....
A quick update on Bens Supercharged bug ...... after getting Bens bug running we took it to South Coast Rotary (SCR) for a run on the dyno to set up the new Microtech EFI & the MSD ignition .
We did quite a lot of set-up and did approx 20 power runs before Kevin @ SCR pulled a little too much fuel out of the mid-range on the tune and the engine pinged heavily at approx quarter throttle ..... He got off the throttle immediately but the head gasket on No.1 cylinder had moved , so it was back to WPVW for head removal .....
several days later we removed the head from Bens' engine & all is well . No damage at all , just the copper gasket got too hot /soft and shifted . We install 2 new head gaskets and head back to the dyno .
We do approx 24 power runs on the dyno again , but cant get Bens' engine to make power !! It makes 332hp@ the wheels at just 4500rpm , but wont breath after that . Now that the blower is 50% overdriven , we are seeing 29psi boost . We are sure that the manifolds that I have fabricated for the supercharger are too small as it makes the boost really early but doesnt maintain it in the higher rev range . We are going to fabricate a new upper manifold between the injection throttle body & the blower over the next week , and then put Bens bug back on the dyno . If we don't see a substantial improvement we will then fabricate a new lower manifold between the blower & the plenums
On the note of the headporting, I thought it was fun.
A famous Swedish tuner Klas Ebbenäs (RIP) built a SC dragster engine way back 25 plus years ago.
He did them out of billet.
Look how he ported them and this is how the engine stands today in storage in South Sweden.
