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Meaning of frustration

benm

By benm,
in Motorsport Discussion & Builds

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Trust33 Grand Master

Trust33

Posted
Posted
Trust33: Interesting comparison, if only I could work out the speed for my 198rwkw graph to do a proper comparison.

I believe i'm changing gears at the right rpm, if I changed any lower i'd lose too much power lower in the gear and have to wait for it to kick in again (like Roy said).

I realise a PowerFC would do me wonders (especially midrange) but that still doesn't explain why other non-PowerFC Skylines are doing better times. Also, i'm trying to improve my times here without spending more money because I believe I have spent enough to get a respectable time :D

Something I realised today whilst driving around Oran Park is that it's taking longer to hit full boost (whether it be 7 or psi) after I change gears. I can actually feel it "kicking in" after I change each gear instead of already being boosted and ready to use like previously.

Bleed valve fault?

Wastegate actuator?

So what roy is saying could be right and loosing that sort of rpm would cause you to loose power in the next gear,and would have more of a detrimental affect on power than i thought.

But when does peak tourqe come in?Usually it is b4 the peak rwkw.Though that close to the peak rwkw you may be way out of your peak tourqe band anyway.

Beer Baron Grand Master

Beer Baron

Posted
Posted

ben, have you had the car on a weigh bridge in race trim, with you in it? Could at least eliminate one more variable for you?

also, interesting point about the boost thing. That's the problem with the dyno it doesn't tell the whole story.

benm Grand Master

benm

Posted
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You mean having 2 hotdogs before I race could be part of the problem? Nah haven't had it on a weigh bridge although I know of 1 on Parramatta Rd.

I think I just need afew mechanics to jump in and take it for a drive and just see what they think rather than dyno work.

VL-man Newbie

VL-man

Posted
Posted

stick in there mate! Just think if you had just built your motor and then whent out and ran a 10 straight out,it would be too easy ....and where would the fun be in that.Drag racing is all about those thousands of seconds.Everyone you speak to says that drag racing is easy...you only drive in a straight line.Until they figure it out for themselves..So stick in there mate.... there will always be someone quicker than you and also someone slower

My advice get an RB-30 VL and boost it up .

Cheers.

benm Grand Master

benm

Posted
  • Author
Posted

Well I took my car back to my clutch mechanic about 4wks ago (ive been to 3 drag nites in the last 3 weeks) just to get it checked and he said it was grabbing fine, selecting all gears fine... but he didn't actually drive it just sat in the workshop with it.

Although... it doesn't grab as hard as it used to (obviously)... I used to be able to sit in the driveway idling, release the clutch slowly and it would pull the car forward into the garage (no throttle required) where as now the revs sorta dip and it wont pull into the garage without abit of throttle.

Trust33 Grand Master

Trust33

Posted
Posted
Question of the week!  Why are most drag cars automatic?  Mmmm I wonder!!

Because there is too much power for a manual gearbox to transplant to the ground,usually,in the lower gears.So a stall converter is added to give the car maximum power where it is most needed.And the other plus would be no changing of the gears just smooth glide.Meaning not as much time lost shifting and loosing revs etc...

NXTIME Grand Master

NXTIME

Posted
Posted

Also, an auto will allow the engine to load (and hence spool turbo) as well as pre-load the drivetrain. A transbrake will hold the auto while it revs to its convertor rpm and then release the car like a slingshot. A manual box simply cannot do this.

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