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Are you using the 8,500 rpm rev limit? If so, I thought you could go a bit higher with an upgraded valvetrain and dry sump. How much top speed would another 500 or 1,000 rpm give you?
 

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Plug Whisperer
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Discussion Starter #102
Good question.

We used to happily rev the motor well over 8500, but found that reliability suffered too much. The reliability issues are in the head and specifically related to the overly heavy and overly complex (and weak) rockers. They're either seemingly impossible to control at RPM (regardless of spring) or simply self destruct. Long story and lot of testing and data sharing around this, but ultimately just built the power in at lower levels and problems resolved... Lowering the limit back to ~8500 has made the motor no less reliable than an 180hp lump, which is exactly what we need at these power levels when on the race track...

So yes, that would give me the speed but potentially at the expense of not finishing... Have to finish to win :eek:

Phil
 

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Vroom vroom
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Everything looks so clean and orderly! Amazing...

If you had the right gears, how fast do you think the car could go?
 

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Well darn :mad:

Thanks for the info. I was under the impression that a dry sump and improved valvetrain was enough to safely take the engine to 9,500-10,000. I was actually working towards this on my Elise to help improve my track times. There are 2-3 turns at the local tracks that top out the rpms a few seconds before the braking zone. I was hoping to stay in the lower gear and save the shifting time.

When is your race? Do you have enough time to swap in the Celica 6th gear? It looks like it drops rpms by 550 and gives a ~10 mph higher top speed.

http://www.lotustalk.com/forums/f157/taller-6th-gear-without-removing-transmission-138882/
 

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KS Speedway coming up this weekend. It's a roval,

The good news is that I'll be taking both a set of c71 kooks and the new new A7s. The A7 construction pushes DOT measurements to the absolute max just like BFG did with the R1. So the A7 is a good bit wider tire than the A6 and therefore a good bit wider than the kook as well...


-Phil
Phil,

Ovals usually require a harder tire compound and higher (much) pressures compared to a road course -- primarily for tire safety/life. Just saying....

Bob L
 

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Plug Whisperer
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Discussion Starter #106
Phil,

Ovals usually require a harder tire compound and higher (much) pressures compared to a road course -- primarily for tire safety/life. Just saying....

Bob L
As always, appreciate the advice, Bob. Duly noted.

-Phil
 

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Plug Whisperer
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Discussion Starter #107
Well darn :mad:

Thanks for the info. I was under the impression that a dry sump and improved valvetrain was enough to safely take the engine to 9,500-10,000. I was actually working towards this on my Elise to help improve my track times. There are 2-3 turns at the local tracks that top out the rpms a few seconds before the braking zone. I was hoping to stay in the lower gear and save the shifting time.

When is your race? Do you have enough time to swap in the Celica 6th gear? It looks like it drops rpms by 550 and gives a ~10 mph higher top speed.

http://www.lotustalk.com/forums/f157/taller-6th-gear-without-removing-transmission-138882/
The trans is a sequential and I have taller gears. I just wasn't motivated enough to swap them. Race before was a 120mph straight, the race after is a 140mph straight. This is the only goofy deal with a 170mph straight. It just wasn't important enough for me to invest the time to drop the trans and swap out the 5-6, just to turn right back around to put the lower 5-6 back in. Working on the sequential is MUCH easier than working on the toyota trans, but dropping the trans is still dropping the trans... and I just couldn't get excited enough about a ROVAL to do it.

I'll do well in the infield... all 5 turns of it! lol:facepalm

No worries though. Even if I get third or forth, I have enough points that I should be fine for the championship going into HPT next month--- so it was a calculated deal. I hold the PCA/NASA/SCCA record at the next track. So as long as the car stays together, I will do well there and the math should be in my favor:cool:

-Phil
 

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Plug Whisperer
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Discussion Starter #108
Everything looks so clean and orderly! Amazing...

If you had the right gears, how fast do you think the car could go?
Thanks. It is the EASIEST lotus we work on. VERY clean, VERY spacious, VERY easy to service.

Top speed: I dunno. Not real sure of the real aero load (drag) and the wing and chassis rake would have a large impact on it, which would be things to tune for top speed...This is the track that I could find out-- maybe next year:D

-Phil
 

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Plug Whisperer
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Discussion Starter #110
Speedway Log

Nice JJ! pretty awesome wing there:D

So the speedway was interesting. First time with the race car on a Roval. It was more interesting than I originally gave it credit.

While heat cycles are heat cycles, there's nothing like a perfectly new and groomed NASCAR/GrandAm track to leave your heat cycled tires looking nearly new. Was a shame removing all that nice looking rubber, but times fall off quick with heat cycles...

When I built my wing uprights, I did not build adjustment that would allow for anything less than 7 degrees of rake. My initial concerns for top speed and this aero package turned out to be a bit less of an issue. Since I couldn't flatten out the wing, the aero drag was enough to keep the car just under 150mph (5mph shy of redline). The vipers in ST1, my sister W2W class, whom I compete with for the overall, don't have near the aero drag and could flatten their wings out to 0. They were runing 10-15 mph faster than me on the oval. My aero drag stalled me at about 8100RPM in 6th for nearly 8 seconds!!! That's a lot of time to lose to another car that's still building speed. Good news is that I made up a lot of time in the infield. Ultimately, I won my class against the GTRs but missed an overall track record by 1 second against the vipers... I've taken the overall against them this year a few times, and if there was ever a track I would lose to them it was this one.

I did try pulling the wing just for giggles. Now, if you're thinking that was a bad idea, you'd be right... really right! --- but you don't know until you try;) As you would expect, a new top speed was met with fantastic enthusiasm bouncing off the rev limiter! Shortly following the top speed (rev limit) the car became nearly uncontrollable and threatened to kill me. The car jumped down to the flat below the banked oval and then back up on to oval--- all at 155mph! It was a trip, lol! Of course the result was me pulling off and into the pits. A lost session, but answered a question and gave me a part to change for the future, ie. need more wing adjustment.

FTR and to save some face, "Lips" pulled the wing on this NA TTB Elise, picked up 8mph and lost 2 seconds... All good things. So I had some precedence for pulling the wing, but our aero packages and speeds are MUCH different, so no real surprise in the different results. Good data for the NA TTB car though!

Engine and trans loads were high with the sustained WOT, RPM, and MPH. Again, the car performed without incident. It's been essentially an arrive and drive car all season and couldn't be happier with the performance and reliability!:up:

Cheers,

Phil
 

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Plug Whisperer
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Discussion Starter #111
Of course, my camera mount gave up after the morning race sessions. Is what it is! lol
Still looking for and learning the braking zones and etc early in the weekend here, but the the times were coming down nicely...

About the only track I've driven with nearly zero visual markers!! Ack!

 

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Jeez Phil what's going on ... You were only 4.6 secs quicker than the opposition !!!
If you had re-geared that could have been as easy 8 secs .
 

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Plug Whisperer
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Discussion Starter #113
I know, I'm slipping right?! :D

Actually, the overall is what I always shoot for. I was a bit frustrated in that I know I left a couple seconds in the infield, which was my only place to make up for the big speed difference on the oval against the Viper team (not on the time sheet, but pulled off a 1:25). I lost the overall to them by about 1 second, so I was there, but just slightly "not dedicated enough" to pull it off! :eek:

I do love to hear the 2ZZ sing like it does when all its ducks are in row:coolnana:

-Phil
 

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I wouldn't say slipping ... But you have set a certain standard that needs to be maintained !!

Is Jims Elise SUper Charged ( sorry don't know your class rules )
I see you are some 12secs a lap quicker .
Would this be the normal margin between you and other less modded / OEM Lotus cars ?

Cheers
Barry
p.s Do the Viper guys talk to you or are they a bit pissed ?
 

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Plug Whisperer
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Discussion Starter #115
Barry-

Jim's is NA. He has rules that cap his power to weight ratio and mods to the car as well. His car makes about 180whp and weighs 1800lbs w/o driver. That's as light or as much power as he can go...

He has has decent aero and very good chassis setup. He's a very good momentum driver as well.

Actually, the viper guys and I get along well. They really struggle with heating issues. I endeared myself to them when I showed them some tricks to keeping their cars from overheating in the race. They implemented the changes (different cooler designs, placement, etc) I showed them and now they take the fight to me every weekend! I actually really enjoy the competition and I think they do too.

As for the margin between myself and Jim, no. This is a weird track with all the straight away. On a normal track and comparable drivers, with shorter time on the straights, we would be a bit closer together. Typically there is 2-3 seconds separating the classes, which should have him 6-8 seconds or so behind me... He's a comparable driver to me, so that rule tends to stick...

-Phil
 

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hey phil,

I took a bit of inspiration from the rear chopping of your clam to reduce pressure and drag, just need alot more power now

Also my mate is talking me into making the wing pylons out of carbon after seeing yours

 

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Plug Whisperer
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Discussion Starter #117
After 12 months on the track, several wins and track records, it was time to tear down the motor on our TT1 car for inspection and improvements.

This motor never missed a beat from October '13 to October '14. We have several significant changes we want to try in 2ZZ-GE land for '15 that we will get into later, but really can't fault this setup.

Combustion looks perfect. Pistons are perfect with no carbon build up. Our Nikasil bores will simply be "deglazed" or plateau honed for the new setup and refresh. The ACL Race Series bearings haven't a scratch on them with 100% of their coating still in tact. Not bad for being hammered away with a sequential trans and well over 400hp in our view.

We use our BOE drysump and Redline Race Oil in this car. The bearings seem to appreciate that:cool:
 

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Plug Whisperer
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Discussion Starter #120
Phil are you bringing the race car to Colorado log. It would fun to see it on the track.
Planning on being at Log, but have not looked into the schedule, track stuff, etc...

I take it that they're doing a track day? It's been brought up that I should have a LOG tuning deal. Still pondering how that might work...

As a side note, I don't think HPR was on our '15 race schedule unfortunately:(

-Phil
 
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