Welcome to Just Commodores, a site specifically designed for all people who share the same passion as yourself.

New Posts Contact us

Just Commodores Forum Community

It takes just a moment to join our fantastic community

Register

355 stroker in vc commodore

355vc

New Member
Joined
Apr 29, 2013
Messages
35
Reaction score
0
Points
0
Location
Brisbane
Members Ride
VC SLE Commodore
Hi,
I recently raced my new vc 355 at the drags and ran a 13.20 @ 103mph full street trim. I am happy how the car ran, however I expected to see a bit lower times considering the specs of the engine. I have only just bought the car and am very happy with it. The engine is apparantly a 308 with scat 355 crank,cast iron heads high flowed,L34 valves, roller rockers,crow cam 240 degrees @ 50 thou, with 495 thou lift, speed pro pistons 20 thou over,full floating scat rods,jp racing oil pump,msd 6AL, 750 demon carby, torque power high rise dual pland manifold with 2" super sucker. Gearbox is full manualised trimatic with 3500 red diamond stall. Diff is 10 bolt LSD with 3.5 gears. Exhaust is pacemaker Tri exrtactors into twin 2 1/2" system.

The previous owner has said the engine made 460hp with the old intake manifold, but should be more now with the T/P manilfold. The car feels quite quick on the street, but at the drags where it also ran sweet only produced the figures above. To me the realistic HP figures would be quite lower than that claimed.The car is running beautifully at idle and at revs, so I don't think there is a tuning problem.

Any advice on where to squeeze some more HP would be appreciated. I would like to stick with the cast heads to keep costs down, as I realise the vn heads would be the way to go. I think there is a good engine here with good potential, but might be something simple I have missed.

Cheers.
 

Attachments

Munz

Right Foot Action
Joined
Jan 23, 2011
Messages
2,276
Reaction score
5
Points
38
Location
Brisbane NTH
Members Ride
VZ Calais LS1 / VL RB30e daily
I believe a 12 is in the bank with your car, What rpm are you changing gears?
Any wheel spin, what tyres were you running and did you remove the spare tyre and jack?
 

355vc

New Member
Joined
Apr 29, 2013
Messages
35
Reaction score
0
Points
0
Location
Brisbane
Members Ride
VC SLE Commodore
I changed at 5900RPM as the rev limiter is set at 6000rpm. Cam rev range is 2900-5900.
Wheel spin was minimal, which I was surprised at considering I was on street tyres. (The track was nice and sticky)
Spare and jack were already out. The car weighs approx. 1500kg with me in it and full of fuel
 

355vc

New Member
Joined
Apr 29, 2013
Messages
35
Reaction score
0
Points
0
Location
Brisbane
Members Ride
VC SLE Commodore
I changed at 5900RPM as the rev limiter is set at 6000rpm. Cam rev range is 2900-5900.
Wheel spin was minimal, which I was surprised at considering I was on street tyres. (The track was nice and sticky)
Spare and jack were already out. The car weighs approx. 1500kg with me in it and full of fuel
 

Sandman

Challenge Accepted
Joined
Apr 8, 2013
Messages
1,445
Reaction score
617
Points
113
Age
26
Location
Melbourne
Members Ride
HQ VC VZ
Were you running on those wheels, they look like 19's or so? If so a tyre with a bit more sidewall might help with putting the power down.
 

355vc

New Member
Joined
Apr 29, 2013
Messages
35
Reaction score
0
Points
0
Location
Brisbane
Members Ride
VC SLE Commodore
Were you running on those wheels, they look like 19's or so? If so a tyre with a bit more sidewall might help with putting the power down.
Yes they were the wheels I raced with and they are a very low profile 20" tyre. The thing is the car launched fairly hard with only minor wheel spin. The first 60 foot time was 1.994,which I realise is not super quick, but a 13.2 @ 103mph is a fairly clean run.The engine should be producing enough HP to give me a few traction problems, more mph and quicker ET's.
The claimed 450 plus HP from the engine builder seems more like around 350HP.
 

2INIL8

Member
Joined
Jun 15, 2009
Messages
151
Reaction score
3
Points
18
Age
40
Members Ride
VH COMMODORE 308
Get it on a dyno,id be wanting to know what air fuel ratio is and
what timing its getting.
Also i believe you dont need those 2" spacers on those manifolds.
If manifolds been changed to a higher flowing one
with a retune its prob lean at wot wich prob reflects the slow et.
 

355vc

New Member
Joined
Apr 29, 2013
Messages
35
Reaction score
0
Points
0
Location
Brisbane
Members Ride
VC SLE Commodore
Thanks, I might try it on a dyno to sort it out.
I have tried it with and without the spacer and the spacer definately makes a big difference to performance, on the street anyway.
The 750 demon has 76 primary jets and 83 secondries, which I thought were quite large, but you might be right ,it still may need more fuel at wot.
 

vyseriesII

The Blessed Hellride
Joined
May 9, 2011
Messages
379
Reaction score
0
Points
0
Location
Australia
Members Ride
2004 VyS S2 Blown
Thanks, I might try it on a dyno to sort it out.
I have tried it with and without the spacer and the spacer definately makes a big difference to performance, on the street anyway.
The 750 demon has 76 primary jets and 83 secondries, which I thought were quite large, but you might be right ,it still may need more fuel at wot.
Could need more fuel, could need less. Timing could also need a tweaking. Or, it never really had 460hp to begin with.

Never believe what a car seller is saying anyway, unless he can produce some sort of proof. They'll tell you anything so you buy it.

Nice car by the way :D
 
Last edited:

ajvx01

Member
Joined
Dec 13, 2010
Messages
911
Reaction score
5
Points
18
Location
North east Adelaide
Members Ride
308 vc
Car looks tuf as hell! Although a 12 should be very doable I'd have thought?


Electrical work, Adelaide all areas.
Pm me.
 
Top