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 11 
 on: Today at 11:05:20 AM 
Started by comet - Last post by MAYOMAN
Salt 27 - yes, I missed seeing those 2 small belly wheels before. Usually they were obscured by the sand screening  them at speed or from the camera angle. Sorry.

 12 
 on: Today at 11:05:14 AM 
Started by Lemming Motors - Last post by manta22
Stainless;

I've wondered about this for a while... a total loss electric system usually loses voltage as current is drained from the battery but that doesn't have to happen. If a buck/boost regulator is inserted into the line from the battery it will maintain 12V output until the battery is totally exhausted. In fact, you could adjust its output to be 12V, 14V, 16V, or whatever you wanted. Has anyone ever used one?

Regards, Neil  Tucson, AZ

 13 
 on: Today at 10:58:17 AM 
Started by Lemming Motors - Last post by Stainless1
I would keep it as simple as possible...  If you want water circulation after shutdown then you will need an electric pump... we do not do a "hot chop shutdown" any more... we used to to make plug reading viable, but that came with a lot of other problems.  The very small valve stems used on 4 valve engines tend to wilt a little making compression and leak down checks fail... yes they straighten when they warm up so the failures move from cylinder to cylinder.  We let the motor idle until the car rolls to a stop.  Keep the water pump.

Total loss electric... we used to do that too... but a lot of ECUs require a minimum of 12v to operate.  Making strong spark at sustained high RPMs uses more power than you think.  Keep the alternator.
My current ECU keeps track of voltage in... the Hayabusa alternator does not keep up... I think the algorithm in the regulator turns output down at higher RPM... something I will be investigating.  But back to you... 2 large batteries take up a lot of room... I already mentioned you don't have a much of that as you think a 20 ft car would.  Start looking at the volume you need for systems....
Don't overly complicate your already complicated endeavor  cheers

 14 
 on: Today at 10:38:42 AM 
Started by comet - Last post by manta22
Malcom;

"Interesting to read how Bloodhound SSC has been seen from across the pond. May I remind readers that setting a new land speed record was never top of the list of goals for that project - enthusing new engineers was the top aim."

I rest my case.... if it wasn't their their primary goal, they sure spent a lot of money on secondary hardware. How "enthused" are those kids going to be now that their inspiration has failed before even getting to Africa? There are quite a few cars at SW that go faster than Bloodhound ever ran- and these cost far less to develop.

Failing and then excusing it by saying we really weren't trying is like the US Navy saying "We weren't really trying to launch a satellite." after the spectacularly failed launch of their Vanguard rocket.

Regards, Neil  Tucson, AZ


 15 
 on: Today at 09:39:00 AM 
Started by Mobacken Racing - Last post by Interested Observer
Anders, regarding the O-ring...
For the edification of all us turbine-ignorant onlookers, could you perhaps elaborate on the oil circulation system?
From observing the recent photos, it looks to me that the curved pipe is the oil supply line to the thrust pads and the oil going past the pads is to be contained by the O-ring except for the gap in the O-ring which provides a narrow escape path for the oil.  Is that at all correct?  If so, where does the oil go after it passes through the gap and how is the suction pump acting on it?  Or, if oil is not intended to pass through the gap, why is there a gap in the first place?  How is the oil scavenged?
The sooty photo shows bits of O-ring material on the exterior of the tunnel.  If the scavenge system was sucking up the O-ring, why are there bits of it on the outside?  Looks like the thread of material has been there for a while, waving around in the wind.
The thrust pad photo shows a clear imprint of the O-ring channel on the “good” side of the oil port but on the other, damaged side, there is no comparable print of the channel and what looks like a contact patch on the ID where the ring could have been squashed.  Are the contact surfaces there sufficiently flat to eliminate an extrusion gap there?
I’m confused.

 16 
 on: Today at 08:00:57 AM 
Started by comet - Last post by RidgeRunner
     All doesn't have to be lost or forgotten about.  There is much value in teaching that identifying and learning from the failures of the big project can be applied to other projects. 

     An old co worker used to say - "Sometimes you just have to back up to get a better run on the hill"...........

                   Ed

 17 
 on: Today at 07:44:35 AM 
Started by Lemming Motors - Last post by RidgeRunner
     No expert here, to which anybody who has seen my pit performances can attest grin  That said, here's my 2 cents:

     Quick shut downs on engines that have been running full speed under load can lead to internal engine hot spots potentially leading to longer term issues.  Metal, especially aluminum, likes to move with temperature changes and doesn't always expand or contract at the same rate in all places at once or always return to the same exact dimensions when the cycle(s) is(are) completed.  One of the reasons we put an electric water pump on my buddy's lakester was for a more gradual cool down to help prevent that just in case.

      Electronics, especially ECU's and injectors, like a constant full voltage for efficient operation.  I know some seem to sneak by with constant loss systems but we run an alternator, feel the small loss in driving HP is well worth the increased efficiency in component operation which also leads to easier and more consistent system calibration and tuning.

                   Ed

 18 
 on: Today at 07:39:09 AM 
Started by comet - Last post by martine
Interesting to read how Bloodhound SSC has been seen from across the pond. May I remind readers that setting a new land speed record was never top of the list of goals for that project - enthusing new engineers was the top aim!
Absolutely Malcolm - and the education side (a separate charity) continues with many ambassadors working with schools and inspiring pupils.  Personally, I do many public bloodhounnd talks to interested groups and have several dates lined-up next year.  It's an interesting, fascinating story but would be better if the car continued.

 19 
 on: Today at 06:38:51 AM 
Started by comet - Last post by Malcolm UK
What happened to the Triumph project?

There is so little news in the UK.  My best guess is that it went back into a US facility for motor rebuilds (it ingested salt) and chassis check after it fell over with Guy at the controls. The deterioration of the salt has been given as a reason to wait out this year. 

 20 
 on: Today at 06:05:27 AM 
Started by Lemming Motors - Last post by Lemming Motors
Hi Sid
My thinking with the electric water pump and a controller was that the water could continue to circulate after the engine was shut down. I am assuming that several minutes at wide open throttle is a lot of heat sink and it could take some time for the circulating water to catch up with it.

Now that the water pump pulley is redundant (on paper at earlky stage), and there is potentialy two or three hp gained from the exercise, the next question would be; do you need an alternator and could you therefore save another one or two hp (data from the interweb so its probably dodgy). Each engine situation will differ but I guess you could reasonably say no belts and pulleys is worth a few ponies on a n/a 2 litre four cylinder.

The engine electrical requirements become a consideration - if I split them into three categories;
1. ECU / spark / injectors / sensors 2. Water and fuel pumps and 3. starting
then I would reasonably assume (and that is the trouble - for assume substitute the word guess) that;

1. could easily be dealt with with a moderate sized battery fully charged - I have no idea how much an ECU would draw over say 5 minutes for 4 injectors and 4 coils,
2. will require more amp minutes so a larger / second battery, and
3. from an umbilical off the push vehicle (or one of those booster packs the car dealers use) cross wired to battery 2. in case of a stall.

All this assumes two batteries will fit and an easily accessbible takeoff point for charging; solar would be readily available with a gennie / battery charger if quick turnaround is required.

The most obvious counter arguement is complication and the need for charging is a pain so a secondary water pump to support engine circulation after shut down using the primary water pump and alternator is much simpler.

Counter arguements (or support for the total loss electrics approach) gratefuly received before I commit to engine water pump surgery.

John

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