User Tag List

+ Reply to Thread
Results 1 to 16 of 16

Thread: 2.9 V6 Super Rod engine

  1. #1
    Mechanic snapper1's Avatar

    Join Date
    Oct 2010
    Location
    Chelmsford
    Age
    63
    Posts
    574
    Thanks
    20
    Thanked 35 Times in 33 Posts

    2.9 V6 Super Rod engine

    A mate has just had a 2.9 V6 running a twin 40 Weber on the Dyno in my opinion he had a good result
    190bhp at 5700 and 200Ft/Lbs at about 4300
    The torque curve was pretty flat
    He of course had high expectations and some of the expectation may have been the bhp claims of other drivers in the series.
    The V6 Super rods run the 2.9 with a 2.8 carb inlet and can run the 38 DGAS or the 40 DFAV or DFI... I think. He was running the 40 DFAV

    What is a reasonable expectation of bhp & torque for this engine for oval racing?
    What little tricks can make a difference

    one more thing they run a distributor which has a 2.9 bottom piece and a 2.8 top it was set to 28 degrees max advance but the best power was found at 39 degrees on BP Ultimate.
    less than a degree either side of 39 and the power dropped off

    i was surprised it needed 39 degrees

  2. #2
    TURBOSPORT SPONSOR Turbosport Subscriber
    Turbosport Moderator
    Turbosport Administrator
    Graham's Avatar
    My Race Car
    My 1st Project
    Join Date
    Feb 2006
    Location
    Ely, Cambs
    Age
    52
    Posts
    23,840
    Thanks
    234
    Thanked 1,929 Times in 1,806 Posts

    Re: 2.9 V6 Super Rod engine

    ignition advance does sound a lot, although the chambers are big and open, and a carb 2.8 inlet will be strangling the engine with regards to air flow, so both those would increase advance requirements, it may also be the crank pulley timing mark is a few degrees out so actual advance is a little less.

    either way the power output sounds healthy, bearing in mind an injected 2.8 made a true 150bhp, carb was 135, the 2.9 only had 150bhp, so 190 on a carb manifold sounds strong to me

  3. The Following User Says Thank You to Graham For This Useful Post:


  4. #3
    Mechanic snapper1's Avatar

    Join Date
    Oct 2010
    Location
    Chelmsford
    Age
    63
    Posts
    574
    Thanks
    20
    Thanked 35 Times in 33 Posts

    Re: 2.9 V6 Super Rod engine

    Thanks for that, the standard figures put it in to perspective
    I to thought that the marking of TDC may be out with a final advance that high, not a big deal as it can be checked and redone
    More of a concern was how sensitive the engine is to exact timing

  5. #4
    TURBOSPORT SPONSOR Turbosport Subscriber
    Turbosport Moderator
    Turbosport Administrator
    Graham's Avatar
    My Race Car
    My 1st Project
    Join Date
    Feb 2006
    Location
    Ely, Cambs
    Age
    52
    Posts
    23,840
    Thanks
    234
    Thanked 1,929 Times in 1,806 Posts

    Re: 2.9 V6 Super Rod engine

    Quote Originally Posted by snapper1 View Post
    More of a concern was how sensitive the engine is to exact timing
    in my experience the engine is right on the compression limit the fuel will stand

  6. #5
    Pit Crew

    Join Date
    Mar 2012
    Location
    Belgium
    Age
    52
    Posts
    1,893
    Thanks
    7
    Thanked 166 Times in 144 Posts

    Re: 2.9 V6 Super Rod engine

    190 Bhp sound very well to me if you are running one twin choke carburetor.

    39 and full power on BP Ultimate, 38 or 40 and power went off ? Sure this operator was not confused somewhere? 39 sound like BP Ultimate is straight Methanol.

    I've tested some "better fuels" in the past and seldom needed a single degree more or less advance for making full power (some could stand pinking very long but power did not raised). 39 is a number I've only seen on some rare antic engines and on some very bad engines. The Ford V6 combustion chamber is not bad enough for 39 and the power is also way to high for being a bad engine. Sure it was not 39 ?

    And one degree on and one of make a drop. That's fast but seen this as well but rare. Usual you see less reaction if you add more. 2 degrees less, with a correct tuned engine must be a drop because we tune minimum best timing. One degree should already give a drop. But adding 2 usual does not unless the CR is high. In this case, again with 39 it can't be high CR.

    Strange

  7. #6
    Pit Crew

    Join Date
    Mar 2012
    Location
    Belgium
    Age
    52
    Posts
    1,893
    Thanks
    7
    Thanked 166 Times in 144 Posts

    Re: 2.9 V6 Super Rod engine

    BTW, you set advance at 28 instead of 39 for max power. What was the drop in power by rejecting 10 ? Should be a lot. Are you using your timing light in steady mode and watching the numbers on the pulley of have the light calculate the advance and flash at TDC mark? I prefer not to have the timing light calculating the degrees because it's a time calculation in function of RPM and can vary quickly.

  8. #7
    Mechanic snapper1's Avatar

    Join Date
    Oct 2010
    Location
    Chelmsford
    Age
    63
    Posts
    574
    Thanks
    20
    Thanked 35 Times in 33 Posts

    Re: 2.9 V6 Super Rod engine

    There are many unknowns as the engine came straight from the builder and as it's a friends engine I do not know the build specifications, like you in trying to analyse from incomplete data.
    The Dyno was run by a known engine tuner.
    Yes he did use a programmable strobe light
    The car would not drive off the trailer and would not take any load.
    First thing the operator did was to check the engine and warm it up slowly then adjust idle, then get base figure for engine, change jets as engine was vey lean.
    He set AFR a little rich and discussed a problem with rear cylinders on the V6 when racing on oval circuits can go lean.

    The race car owner wants reliability after having had 2 stock engines break at early attempts to race.

    The first power run after a safe AFR was set gave about 155bhp the final figure was 189.4 bhp with 199.8 Ft/Lbs
    Throughout the session there was talk of other available carbs and another racer who came along is going to test with all 3 carbs later in the year.
    Port matching the manifold and some other work was also discussed and the racer is going to source some more heads and manifold.
    There are tight limits on what the Super Rod formula allows.

    Last bits from memory was that the engine has forged rods and reved to 7300 but peak bhp was at 5718 rpm

  9. #8
    Pit Crew

    Join Date
    Mar 2012
    Location
    Belgium
    Age
    52
    Posts
    1,893
    Thanks
    7
    Thanked 166 Times in 144 Posts

    Re: 2.9 V6 Super Rod engine

    All sound very common and normal.

    Only, setting the ignition at 28 while full power was at 39 and even 1 less was making less power. Still wondering how much power there was lost by cutting back more than 10 ? I can understand he want to be save but if you make full power at 39, it will nog longer be safe if you cut back 11. It will overheat the exhaust valves and put a lot of heat into the water system on the exhaust side.

  10. The Following User Says Thank You to onyd For This Useful Post:


  11. #9
    Mechanic snapper1's Avatar

    Join Date
    Oct 2010
    Location
    Chelmsford
    Age
    63
    Posts
    574
    Thanks
    20
    Thanked 35 Times in 33 Posts

    Re: 2.9 V6 Super Rod engine

    To clarify
    Engine was set at 28 degrees by engine builder
    After Dyno engine set to 39 degrees and gives best power
    Power difference was about 30bhp

  12. #10
    Pit Crew

    Join Date
    Mar 2012
    Location
    Belgium
    Age
    52
    Posts
    1,893
    Thanks
    7
    Thanked 166 Times in 144 Posts

    Re: 2.9 V6 Super Rod engine

    OK, now I got it. I thought they returned to 28 and left it that way. Would have been horrible. 30 Bhp would be a normal "lost" of power if you back off so far.

    Still a lot. I do know on rolling road they usual come with an advance number higher as what I find on my dyno to be correct. Specially in a fast "run" mode (a few degrees, not 10). The timing lamp can also calculate a small error and timing disc can be out slightly (reason why I only use them fixed and set marks at the pulley). I would think, 34 would have been max if CR is correct and a good engine (and it is a good engine).

    They did not forget to disconnect the vacuum advance while setting the ignition (if any is still in use) ?

    OK, if full power is 39 it's 39.

  13. #11
    Mechanic snapper1's Avatar

    Join Date
    Oct 2010
    Location
    Chelmsford
    Age
    63
    Posts
    574
    Thanks
    20
    Thanked 35 Times in 33 Posts

    Re: 2.9 V6 Super Rod engine

    Vacuum detached for racing and Dyno runs
    I agree timing light, timing mark could be out
    34 degrees sounds more reasonable.

  14. #12
    Pit Crew

    Join Date
    Mar 2012
    Location
    Belgium
    Age
    52
    Posts
    1,893
    Thanks
    7
    Thanked 166 Times in 144 Posts

    Re: 2.9 V6 Super Rod engine

    Well just to give you an example. This week I've dyno tested an old Vauxhall 2300 engine (like in the Bedford CF). Car has been sold to DTV Belgium many moon's ago. I had it on the dyno before but carb was impossible to tune and no torque. Wanted to fix both problems in one motion and fitted one of my special "modern" profiles. Torque raised from 115 Nm to 168 Nm at 2000 RPM and most important I could tune the carbs as written in the carburetor books. Piece of cake.

    Max torque was 230 Nm, before 211 Nm but max power is still low, 152 Bhp (same as with the original cam but 400 RPM earlier) but seems like these numbers where normal those days . I call this a bad engine and engine did not made max power before I dialed in 38. I have a feeling the CR may a little low but I have no idea how much it is.

    This ignition advance number is normal for a poor Bhp (and for sure not high CR) engine. But I can't say your V6 is low power, I feel high power so very interesting it need so much advance. We learn every day.

  15. #13
    Tyre Kicker

    Join Date
    Jul 2009
    Location
    Evesham
    Posts
    13
    Thanks
    2
    Thanked 0 Times in 0 Posts

    Re: 2.9 V6 Super Rod engine

    There is a few 2.9's making around the 230-250bhp mark.

    They all use the Kent v6T46 cam which is a must to be honest.

    One example makes 254bhp at 7000rpm on 35 advance. Peak torque is 225 ft/lbs at 4500rpm at 36 advance.

    Running 3 x 40 DCNF's

  16. #14
    Pit Crew

    Join Date
    Mar 2012
    Location
    Belgium
    Age
    52
    Posts
    1,893
    Thanks
    7
    Thanked 166 Times in 144 Posts

    Re: 2.9 V6 Super Rod engine

    Yes, 3x 40 DCNF is an other story and best setup you can create with this engine. I don't have enough experiences with this engine to compare but still surprised they need that much advance. Compared to other engine with look-o-like heads and bore / stroke it a lot more as what I'm used to see.

    On the other had, V8 engine (bores over 100mm) usual also need 34

  17. The Following User Says Thank You to onyd For This Useful Post:


  18. #15
    Tyre Kicker

    Join Date
    Jul 2009
    Location
    Evesham
    Posts
    13
    Thanks
    2
    Thanked 0 Times in 0 Posts

    Re: 2.9 V6 Super Rod engine

    They love advance.

    Even boosted making over 400bhp 25 of more advance is not uncommon.

  19. #16
    Bodger

    Join Date
    Mar 2009
    Location
    sussex
    Posts
    142
    Thanks
    5
    Thanked 7 Times in 7 Posts

    Re: 2.9 V6 Super Rod engine

    Old post I know but.... my engine before i had turbo'd hit 42 advance in places on my N/a map. this was by a well respected dyno owner.
    On WOT between 3000 to 6000rpm it is 38 to 39.5 adv
    engine specs were
    185Bhp - 205 ft/lb limited to 6200rpm but power was wanting to continue through. (needed to strengthen block first before going higher )
    2.8 cologne
    std bottom end
    kent cam sports R
    mild ported head
    2.8efi manifold
    megasquirt Ecu.

+ Reply to Thread

Bookmarks

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts