Just Commodores Forum Community

It takes just a moment to join our fantastic community

Register

What to do - rebuild?

Discussion in 'VR - VS Holden Commodore (1993 - 1997)' started by Dean1985, Feb 25, 2020.

  1. Deuce

    Deuce Super Stock

    Messages:
    2,248
    Likes Received:
    662
    Trophy Points:
    113
    Joined:
    Feb 5, 2012
    Location:
    Meremere Dragway (as often as possible)
    Members Ride:
    '94 VR SS V8
    I drive a VR 355" with 9.3comp and a short cam like yours (4502 Crow). It is such a prick fighting the brakes. It used to idle along at 13kph before you even touch the throttle (even when towing).
    Bigger headers and intake mani helped drop idle torque. But stally is what I really need at some stage.

    P.S going from 3.08 gears to 3.45 gears changed cruise rpm on the highway from 1900 to 2100. Basically nothing really and you soon get used to it.
     
    afstruct likes this.
  2. Dean1985

    Dean1985 New Member

    Messages:
    24
    Likes Received:
    2
    Trophy Points:
    3
    Joined:
    Nov 15, 2018
    Location:
    Nowra NSW
    Members Ride:
    VR S2 V8 Auto
    Thanks @EYY.
    I believe i will drop at 284 in and go with that.

    Whats the g.o with the brakes issue with a bigger cam?
    Does it help that im running a dual diaphragm booster? (If its a vacuum issue).

    What would be the notable downsides to a 284 (other than temptation to spin wheels)

    Thanks again all you posters. Amazing work.
     
  3. Vin999

    Vin999 Active Member

    Messages:
    272
    Likes Received:
    71
    Trophy Points:
    28
    Joined:
    Dec 1, 2019
    Location:
    SA
    Members Ride:
    Vsedan
    Hey Dean, Listen to Eyy and Gtrboyy’s posts @ very good advice and don’t make the same misteak twice, ditch the 268 beache.

    The 268 and 276 cams are basically what HSV used with a compression of 9.0. Standard ratio is 8.5. HSV ran twin throttle body manifolds and had larger valves in basic heads.

    On stall info, standard stock engine stall is 1600 to 1800 revs, so choose stall speed to suit the power band of your cam basically. Cam manufacturers give the safe rev range.

    The 268 powerband is 1500 to 4000 revs.
    The 276 powerband is 1800 to 4500 revs
    The 284 powerband is 2200 to 5500 revs so a 2800 stall is ideal.
    The 286 powerband is 2500 to 6000 revs so a 3000 stall is ideal.
    The 284 n 286 need a 9.5 ratio minimum

    If you choose a much higher stall it just means you will bolt/flash out like a rabbit immediately and then quickly turn into a turtle losing power.
    All these cams can drive ok like sheep with the standard stall. Like EYY said you need to drive a stalled car and have the right foot problem understand the driving benefits. But these cams need a good diff ratio, stall, headwork and exhaust to benefit fully.
     
    afstruct likes this.
  4. afstruct

    afstruct Well-Known Member

    Messages:
    859
    Likes Received:
    745
    Trophy Points:
    93
    Joined:
    Dec 10, 2015
    Location:
    Warners Bay
    Members Ride:
    HSV VS Maloo , 2002 Monaro
    As everyone is saying, you have a great base , swap to the right cam , stall, an diff = you'll absolutely love = great sound and performance = you'll not be disappointed = where it's atm = a very entertaining classic/ older daily = dam I miss dailying my vs maloo= soo much character compared to the hatch= daily = absolutely enjoy it while you can
     
    losh1971 likes this.
  5. Deuce

    Deuce Super Stock

    Messages:
    2,248
    Likes Received:
    662
    Trophy Points:
    113
    Joined:
    Feb 5, 2012
    Location:
    Meremere Dragway (as often as possible)
    Members Ride:
    '94 VR SS V8
    I found that it is basically the motor making too much torque at idle.
    The engine wants to go and you need to hold it on the brakes.
    A bigger cam will solve the problem as it moves torque up the RPM range, or more stall speed on the converter as that will slip more torque at idle.
    You won't want to over do the cam without upping stall as it would be doughy real early in the RPM. And as mentioned, you have a lock up converter so large stall speed isn't an issue for you at highway cruise.
     
  6. EYY

    EYY Well-Known Member

    Messages:
    5,009
    Likes Received:
    1,085
    Trophy Points:
    113
    Joined:
    Mar 6, 2011
    Location:
    Vic
    Members Ride:
    VS Statesman
    Idle speed is issue with pushing on the brakes. The larger the cam, the higher the idle needs to be for it to run smoothly without too much chop or risk of stalling. At standard idle speed you generally won’t have issues with pushing on the brakes but may have stalling issues coming to a stop etc.

    Keep in mind that the 284 is still a baby in the camshaft world. You won’t have issues. If you haven’t already, it may be worth considering a vt front brake upgrade. The stock brakes are scary with a v8.
     
    Dean1985, Vin999 and woteva like this.
  7. someguy360

    someguy360 Well-Known Member

    Messages:
    2,282
    Likes Received:
    432
    Trophy Points:
    83
    Joined:
    Jan 29, 2011
    Location:
    Adelaide Hills
    Members Ride:
    94' VR 304 - 05' Navara - 17' Focus - 12' Sorento
    Ain't that the thruth
     
    Vin999 likes this.
  8. vr304

    vr304 Well-Known Member

    Messages:
    1,326
    Likes Received:
    305
    Trophy Points:
    83
    Joined:
    Feb 9, 2013
    Location:
    Auckland, New Zealand
    Members Ride:
    2007 ssv manual
    Yip I’ve always wondered why they put such piss poor brakes on a big heavy car with a v8 up front, even my VE SS brakes aren’t all that great in my opinion anyway getting off topic now lol
     
  9. Vin999

    Vin999 Active Member

    Messages:
    272
    Likes Received:
    71
    Trophy Points:
    28
    Joined:
    Dec 1, 2019
    Location:
    SA
    Members Ride:
    Vsedan
    going downhill with an auto and no engine braking is a thrill, why auto drivers have hand on h/brake lever not the trans lever ;)
     
  10. VS 5.0

    VS 5.0 Well-Known Member

    Messages:
    4,656
    Likes Received:
    4,611
    Trophy Points:
    113
    Joined:
    Jul 17, 2006
    Location:
    Perth WA
    Members Ride:
    VE SSV Z Series M6
    I'm glad mine has the Brembos.
     
    keith reed, vr304 and Vin999 like this.
  11. vr304

    vr304 Well-Known Member

    Messages:
    1,326
    Likes Received:
    305
    Trophy Points:
    83
    Joined:
    Feb 9, 2013
    Location:
    Auckland, New Zealand
    Members Ride:
    2007 ssv manual
    I’d love to get some myself but don’t have a lazy 2 - 2.5k sitting in my bank unfortunately, although I’m thinking of buying some safe brake braided lines which will probably help somewhat
     
    VS 5.0 and losh1971 like this.
  12. woteva

    woteva NEED 4 SPEED

    Messages:
    1,433
    Likes Received:
    1,317
    Trophy Points:
    113
    Joined:
    Jul 18, 2005
    Location:
    Adelaide S.A.
    Members Ride:
    VE2 Sportwagon - VR2 V6 ecotec Wag - VS2 V6 Wag
    Looking at this for my next VS project - 320mm 4piston Willwood bolt on kit.
    Under $1300 including new front brake hoses
    https://www.rodshop.com.au/holden/v...e-320mm-4-piston-wilwood-front-brake-kit.html
     
    Dean1985 and losh1971 like this.
  13. Dean1985

    Dean1985 New Member

    Messages:
    24
    Likes Received:
    2
    Trophy Points:
    3
    Joined:
    Nov 15, 2018
    Location:
    Nowra NSW
    Members Ride:
    VR S2 V8 Auto
    Alright you bunch! I agree with the brakes. Poor. I really thought maybe it was just my car, turns out...

    Anyways, i have sent some requests to Camshaft suppliers and had varied responses as below.

    (This isnt a case of someone being an 'askhole', you have all resigned me to the fact i need to swap the cam, dont rebuild, dont build the engine to match the cam. But im going to do extra due diligence because 3 isnt a lucky number, i want to not have to revisit this again)

    I shot an email to Crane, Crow, Camtech explaining basically what i have to you bunch and this is what i received (In Summation).
    (sent email attached) Cam Request.JPG

    Crane - Helpful, responsive.
    • Not an ideal situation…..
    • A question I can’t really answer, as your compression ratio is a guesstimate
    • Technically you will need to step up to a 286 #884301
    • Hard to say if the 284 has enough overlap to cure your problem !!!!
    • Could/should/might be ok…. Hate for you to install one and its still detonating
    • As for converter stall….everyone has a different thought
    • BUT you will sacrifice low end torque and need a small (approx. 2200) stall converter (Please email Dominator for their input)
    • Unfortunately not really suited to your main usage
    • You might want to try a good high output ignition system
      • I would suggest a Crane/Fast HI-6 Box & LX92 coil
    • The increased spark output and low RPM multispark could be enough to fix your problem

    Crow - Helpful, short responses (leaving me unsure if the request was given the thought required)

    • At first a cam was suggested and an order sheet was supplied with no word from the technician Crow Cam.JPG
    • I replied asking if this would fix the issue i provided.
    • A day later i received an email saying "Yes i think this will solve your problem" from the head of "The Head Technical Department"

    Camtech
    .No response.
     
    woteva likes this.
  14. EYY

    EYY Well-Known Member

    Messages:
    5,009
    Likes Received:
    1,085
    Trophy Points:
    113
    Joined:
    Mar 6, 2011
    Location:
    Vic
    Members Ride:
    VS Statesman
    That crow cam won’t help you. The crane reply is the most appropriate - remember that they’re covering themselves in that email. You really need to talk to them over the phone.

    You don’t need to alter the ignition system. There are plenty of salespeople out there that aren’t familiar with engine combos. You’re better off calling them and chatting to them - they’ll be able to help you more that way.
     
    woteva likes this.
  15. Vin999

    Vin999 Active Member

    Messages:
    272
    Likes Received:
    71
    Trophy Points:
    28
    Joined:
    Dec 1, 2019
    Location:
    SA
    Members Ride:
    Vsedan
  16. keith reed

    keith reed Well-Known Member

    Messages:
    280
    Likes Received:
    316
    Trophy Points:
    63
    Joined:
    Sep 26, 2010
    Location:
    Raceview Qld
    Members Ride:
    1983 vh v8 sle 2000 vs v8 ute 2012 ve11 redline
    I am surprised you didn't have a response from Camtech. I have found them helpful on the two occasions I have contacted them. On both occasions they had different specs for the same cam. They corrected the errors immediately and advised me at the same time.
     
  17. gtrboyy

    gtrboyy Well-Known Member

    Messages:
    1,647
    Likes Received:
    468
    Trophy Points:
    83
    Joined:
    Jan 25, 2006
    Members Ride:
    vt ss & lc gtr
    Yet to use them but heard only good things about Camtech from well known engine builders.

    Also helps they're in Sydney so 100% will pay them a visit before buying parts.
     
  18. Deuce

    Deuce Super Stock

    Messages:
    2,248
    Likes Received:
    662
    Trophy Points:
    113
    Joined:
    Feb 5, 2012
    Location:
    Meremere Dragway (as often as possible)
    Members Ride:
    '94 VR SS V8
    At work I base cylinder pressure on intake closing point. Later close = less pressure.
    And looking at the Crow recommended (and my 355 has a Crow) they appear wrong. Your current 30° close would step back to 28° and in theory create more pressure at low RPM worsening the situation.
    Although, cam cards do only show a snippet of information and crow may (will) know far more details about both cams which might prove something different. IE- lazier ramps.
     
  19. Dean1985

    Dean1985 New Member

    Messages:
    24
    Likes Received:
    2
    Trophy Points:
    3
    Joined:
    Nov 15, 2018
    Location:
    Nowra NSW
    Members Ride:
    VR S2 V8 Auto

    Just spoke to a guy at CamTech cams. VERY helpful as suggested.
    He suggested a CT248513. Which has .511 lift.
    With the current diff ratio he suggested a 2200 to 2500max stall.
    He questioned whuch springs i had as well in the heads.
    The spring i have, have a max net lift .487.
    He said it needs to be measured and may not require other springs.
    Do you have info on this sort of thing?

    Crane recommended a particular spring (350$ ish and new collets) to suit said lift. (Things are getting pricey quick.

    Anyone have an opinion on a Crane H284 vs Camtech CT248513?

    The Camtech has more lift and requires different springs. Thats the only difference i can see.

    Cheers fellas. Imhoping to order tomorrow or wednesday.

    P.s i have shot an email to Camtech on their valve spring suggestions so i can get the kit from a single supplier.
     
  20. losh1971

    losh1971 Well-Known Member

    Messages:
    7,816
    Likes Received:
    2,499
    Trophy Points:
    113
    Joined:
    Jan 17, 2010
    Location:
    North Tas
    Members Ride:
    VR Ute V6
    If you're going to spend $800 -$900 on a HD stally it would be a waste to go 2500 better off going 3000. But don't take my word for it, do some research and you should find that 3000 is the go over a 2500. Having a 3000 myself i can say there us no adverse affects that I can tell in the way of drivability. Glad I listened to the TC builder and went 3000, over a 2500.
     

Share This Page