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Engine Configuration pictures + information

if you have a 4G52 or 4G54 thats been modified in any way post your pics with a brief description of the configuration and how you believe it compares to its factory set up.

info to include:
Engine series - 4G52/4G54 Astron one or two
Head - weather any work was done - if so what?
Cam - factory after market or regrind - solid or hydraulic tappets
Injectors - what there from/flow
Extractors - factory if not then what?
ECU- for turbo and efi systems

good opportunity to show off your engine bay and possibly inspire others

ill get the ball rolling


( still sorting out induction hose from the throttle body to the airbox )
4G54 Astron 2 - balance shaft deleted
modified TR magna EFI to RWD Plenum
M28 head, port matched as im using a DIY adapter plate to match the small rear coolant port to the Larger coolant port on the TR magna manifold
Factory TR magna roller rocker cam wit hydraulic tappets
Factory blue top TR magna injectors
pace maker extractors
factory TR magna ecu

crap loads better

Well, what the hell. alot has changed since this was taken, but essentially it looks almost identical
its been in 3 cars so far, soon to be a 4th and final track scorpion, just for fun.


Astron 2, magna block with welsh plug in back
Stock Astron 1 pistons from a 200,000 k old sigma at U-Pull it
Stage 2 RPW turbo cam.
Stock untouched M4 head
TR intake with XF throttlebody
380cc Nissan CA18DET injectors
Megasquirt 1 ECU
std sigma exhaust manifold with T3 adapter plate welded onto it.
Tial style (ebay cheapie) wastegate 38mm
$100 ebay T3/T4 turbo
450x300x76 Intercooler
209kw @18PSI (what felt like 250kw @22PSI with larger injectors) until the old sloppy pistons and rings cried enough


since then its been rebuilt with ARP Bolts, peened rods
ported and flow matched M6 head
balance shaft delete
modified oil pump
new ACL Duralite 1mm OS pistons
800cc untimate racing injectors (bosch i think)
Megasquirt 2 ECU
GT35R Turbo
AU Falcon throttle body (has a PWM idle valve not a on off type)
power... ? ? ? never run in this configuration yet.

here's my hi comp

Engine series - 4G54 Astron two
Head - Astron one ported, polished, flowed, over size valve's
Cam - Solid stage 3 wade cam
fuel system - 32/36 dgf weber caby tricked up, ported inlet manifold
Extractors - Pacy's 2.1/4 system, hotdog, straight through muffler

power 146 - RWHP on McDonald bro's thomostown with old A2 bottem end, no balance shafts

sadly no pic of the engine bay

But I ran an A1 block and head
downdraught weber conversion
chrome sports air cleaner
OTS Lukey extractors with custom twin exhaust
Sigma Turbo rocker cover (the wrinkle finish black version)
engine covered in wrinkle finish black



With the next project i plan to do all this

A2 block bored out to 2.8L (maybe even bigger)
Bottom end fully balanced
A1 head ported, polished
A2 roller rockers installed (If can be done)
Ported and polished head
Bigger valves with 3-angle valve grind
increased compression to somewhere of about 11.5ish:1
the same custom exhausts as of old car (painted in black header paint then wrapped in header wrap to absorb as much heat soak as possible)
a twin carb inlet manifold....with weber or solex carbies
carbies running spacers to push them through the hole in the bonnet and the chrome air cleaners visibel outside of the car
The wrinkle finished rocker cover from old car
Then have the whole engine painted in black header paint to absorb as much heat soak as possible again...then paint in wrinkle finish black
install electric fuel pump
install electric water pump
install thermo fan onto a (possibly) S13 nissan silvia radiator

4G54 Astron II

PARTS
1. Bronze valve guides
2. 1mm OS stainless valves and double valve springs.
3. High comp ACL Duralite pistons.
4. Swivel foot tapets.
5. TS Magna oil pump.
6. Balance shaft eliminator kit.
7. ARP head studs
8. Motorbike carbies.
9. Lightened Starion flywheel
10. Starion clutch.

WORK DONE

HEAD:
M7 Magna head.
Ported.
Combustion chamber smoothed to reduce shrouding and hotspots.
decked 1mm (69cc chamber).
Stage 3 Camtech cam.

BLOCK
Decked 1mm.

9.6:1 Compression ratio.
99.3KW at the rear wheels.













Cheers.

I gotta say, you guys have got me pretty excited.
After reading through the mods I am thinking the old girl might be good for 110-120rwkw which will be very exciting only pushing 900kg

Magna Astron II block fitted with flat tops and balance shafts removed.
Astron I 4G52 head, ported and faced
Lumpy cam (unsure of spec)
Should run about a 13:1 compression ratio
Custom extractors and 2.5" system with super turbo muffler and twin cannons at the rear
Redline manifold and twin 48mm Delorto side drafts.

my engine went though a bit a development over a few years and most work including most machining and assembling I did my self
the first engine I built for my hillclimb/circuit car was a 4g52 and that was in 1999 and the car was CAMS log booked that year - the 2 lt made 84 Kw atw
I'll try to list it as its last and most up to date configuration

astron 1 4G54 block up 0.060" flat top piston zero decked with the pistons releaved on the inlet side for valve clearance
std rods polished and shot peaned and balanced fitted with ARP bolts ( resized of cause )
crank reduced in weight and polished - balanced of cause
custom made crank scraper - balance shaft removed
custom made sump with trap door baffles , larger volume and modifide so the engine could be moved back in the engine bay
the engine sits 65 mm back in the engine bay
it also runs a very light custom made billet flywheel

the head is astron 2 and started its life on a magna it had 3.5 mm machined off the face to lift the comp - there has been some port work ,the guides were bulleted ( tapered where they go into the port ) the valve seats were opened up to the outer edge of the valve - the seats were 3 angle cut and the valve were back cut
double valve springs and the cam run about 300 degs on the inlet and 310 degs on exhuast
to dail the cam in I fitted a redrilled cam gear



the custom header is a 4 into 1 system using 1 3/4 tube with mandel bends and straight sections tig welded up and all pipes are with in 3 mm in lenth of each other and run into a 2.5" system



induction twin DCOE 13 webers with custom made 41 mm chokes and no air cleaners
the ignition curve was modifide for less advance in the curve and runs 30 deg total timing

this configuration got 119.5 Kw atw @ 6100 rpm with a very wide spead of power on the track it pulls out of slpw corners from around 2000 rpm with the cam coming on at 3000 to max at 6100 but I run the engine to 7200 at times to save a gear change



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the engine needs a rebuild now and the future mods will be a lighter knife edged crank with a new crank scaper
a light billet flywheel and a much lighter clutch
a M9 magna head with OS SS valves and more compression
50 mm quad TBs
maybe a larger set of headers with 1 7/8 "tube
and a larger cam grind

4G54 II, fully rebuilt, magna head with hydraulic lifters and aftermarket cam, high performance valves and springs, new crank and sump, magna reversed plenum with a bosch falcon throttle body, 800cc injectors, hks external wastegate and blow off valve, garrett air reasearch turbo with high mount manifold, microtech ltx-8 ecu with digidash, bosch 044 fuel pumps and a bosch gt40r coil i have it bolted to a forged jap 5sp with an excedy sports tough clutch, the engine was built by james performance in canberra and puts out 254kw at the rear tread