Alright I'm in.

Plan:
2450lbs Min Weight
158 Max Avg WHP
225mm Hoosier R7
-0.7 A-arm Suspension
-0.5 Front Splitter

Revived the ol' build thread as well. Link in sig.

 

I guess I'm running TT5 now too.....



~2300lbs wet
135rwhp peak / 128 avg
205 R7s on 15x8
9LR Swan-Neck (10.5" off rear bumper) 0 AOA
HDPE air-dam, 9LR prototype, unfortunately no ducting
3" splitter 10mm alumalite (spare material)
800/500 Xidas 1.125" RB/14mm
5spd /4.3



James posted his laps first, the faster ones. I'll post my pleab laps in my build thread later. FWIW Eric Powell in his PTD car also did a 1:19.xxx at ~160rwhp.

 

Noice. So do you have any plans for getting a little more optimized? Right now your sheet should look like... 2293 min weight and 147 max avg whp for exactly 14:1 adjusted. Take more weight out? Junkyard VVT swap on e85 and hope for like 145 peak whp? Little column A, little column B?

EDIT: Also someone needs to petition grid life to go from 3" to 4" on the splitter rule so ST4 and ST5 cars can jump between easier. Lol.

 

Yeah, guna shoot for some more power over this season. My block is in good condition, but my head is pretty rough. Planning to get a +1 valves,light-double, p/p, deshrouded, BP4W head. Install my 5A cam, FINALLY get an ECU(I'm still on stock). Then cross fingers for enough power to run 2400lbs. I believe 2450lbs is the sweet-spot, but I dunno if I can make the power for that. So I could settle on power for 2400lbs and be happy. I'd also get to run 9s.


This was my first experience with aero, any aero for that matter. My top speeds were much higher vs 2 years ago, but I also gained 5hp and dropped ~140lbs. The one thing both my co-driver and I noticed was how much more settled the car was on a slip angle. To keep it consistent, we'll use my alien co-driver as an example for this youtube comparison. Noting his larger inputs on the older video with no aero was the take away from this IMO.
NASA TT5 Track Record Lap Roebling Road - 1:19.499 vs. NASA TTE Roebling unofficial track record - James Cathers by VJ why we slap | YouTube Doubler | Mashup Helper


Edit: I think the 3" was for STL cross-over? Easier to cut 1" off instead of asking other people to add 1"? I wonder if that 1" makes a difference........... that's what she said?

 

Are you thinking about running Nationals at Mid-O?

Registration opened today and I'm wondering how big of an ST5 class we are going to have.

 

I'd only be doing TT5, I can't afford to do ST5 this season. I'd love to be there, but we'll see. I have a feeling ST5 will have solid numbers at Mid-O, though.

 

Good plans. I'm kind of in the same boat, hoping to make enough to run 2450lbs with 225 R7's, and then also have a classing sheet for 2400lbs but with 245 RC1's and I wouldn't have to change power.

Also you would have been faster without changing power or weight thanks to the aero. Your corner exit speeds would be higher and with the tried and true S1-esque aero package it's surprisingly got less overall drag as well. When I changed nothing but aero I picked up speed everywhere and high speed stuff got way more stable. Another thing that gets noticeably better is braking from high speeds, I can stand on the pedal a LOT harder now.

 

I need a 4.3 Giken and some Tomei cams.

My motor, since you're both in similar boats:
BP4W
+1 valves
Light doubles
BP5A cam
Mild head work; bowl blend, deshroud, exhaust ports ported.
10.5:1 OEM JDM NB2 pistons
rods/bearings/studs
OEM NB2 oil pump.

This 151.44 run turns into 140 NASA Avg.
My sheet is 144/2250
4" splitter/wing
205 R7 on 8"

Gains to be made with a Supermiata tuned OSGiken, more mass centralization/ballast, then its just finding more power with cams.

ProTip: If you're going to build a bottom end, just jump straight to 85mm 11:1 pistons. My 83.5 10.5:1 were cheap($28-35 Mazda Comp from Japan) and I can still throw a TSE EFR kit at it later.

 

Almost makes me wonder if I should try to go straight to a CNC'd head and Tomei cams in the BP6D... I thought I would be able to make the power with stock cams, cleaned up head, and 83.5mm 10:1 pistons. Fack. That's like another $2500 into the engine though.

Or maybe... skip CNC head, do the Tomei cams (y u expensive VVT...) and put in 11:1 83.5mm pistons and if I go turbo later, try to sell pistons and put in 8.6:1 later.

 

Super lame.

I need to go measure my Singular hood vents...

https://community.drivenasa.com/topi...on-highlights/

 

Did a quick check on my NC vents and got 5/8"...

Is it just for people claiming BTM aero or all cars?

 

It is enforced for all cars in ST4, ST5 and ST6.

In ST3 it is only applicable to cars claiming BTM aero mod factor, because if you don't take that mod factor then aero is very open, unlike the slower ST classes where it is defined and regulated. For ST1 and ST2, aero is very open there as well so doesn't matter.


I would highly suggest anyone that is negatively affected by this rule, to immediately start complaining in this thread and maybe they can revise the limit to be like 3/4" or 1" to better align with the spirit of the rules...

https://community.drivenasa.com/topi...on-highlights/

 

According to Greg, the Max height with the CCR tolerance is 7/16".

I'll be measuring mine tonight to see where I land.

 

My Singular vents are illegal. Now to find and buy a new hood.

 

Measured my gen 1 Singular vents......







I might grind these down or maybe remove them entirely, not sure yet. I suppose this gurney flap in front of the vents does help.

 

I have the gen2 Singular vents that don't have the removable gurney flap and measured it at just shy of 3/4" at their highest point as they curve upward toward the middle. Obviously difficult to accurately measure as stated in the thread on the NASA forums.

 

Got my check ride to move up from HPDE4 and had my first few sessions of TT last weekend with NASA TX in Hallett. The car has the power to weight of a tt6 car, but has aero for tt5. I ran a best lap of 1:27.82, which was good for 2s and change over the TT6 track record that got reset the same session so I guess the aero works. I'm still relatively inexperienced but thought I put in a pretty good lap.

134 peak hp/128 avg
2400 lbs min weight, probably running closer to 2450
9LR wing
Airdam w/ 4" splitter
245 RC-1 on 15x10 dekagram
800/500 Xida Gen1
1.125 RB front bar/OEM 1.6 rear
6spd/4.1

 

Nice lap, dude! I would expect the TT6 record to be in the 28's, low 29's at worst if David was there. I ran a 1:29.6 last year and he ran 1:28 on what were effectively TT6 setups. I have sway bars and slightly less spring rate now, which is easier to drive. Running my ideal setup of 6 speed/4.1 or 4.3 (vs 5 spd/4.78) and 225 hohos (vs 205) for a track like hallett should def be 1:28. So basically, take your aero off unless you have plans for TT5 power and give Fred a run for his money

 

I originally thought the car made more power so I stuck aero on it to meet TT5 rules, I'm still not convinced it makes as little power as the dyno said, but when I did my certification it only made 134. When I first had it tuned it put down something like 160 whp, so I'm guessing the motor isn't in the greatest health after almost two years of tracking it with the rev limiter raised to 7500 and a few over-revs.

6spd/4.1 is a little awkward at Hallett because I end up sitting on limiter in 4th for 2-3s combined per lap going down both straights, I don't think the shift up to 5th is worth it.