TT points question - engine related

[Aardwolf]

"Engine/drivetrain: 5) Modified or non-OEM camshaft(s) or cam timing gears +6 (for one or more)

 

Does this mean if I replace the stock timing gear I have to take the points? My car is an '88 and there are no more stock cam timing gears. I need to replace the timing chain due to age and mileage, I'm not converting it to gear drive or anything. Is the rule more to catch going to gear drive or something? The aftermarket timing chains all come with a new crank gear and a new cam gear.

[IGZOSTD]

I think you have to take the pts anytime you alter the valve-train, cam drive, and cam.

I suggest you write Greg a message and appeal to him. If you can prove to him it will not alter timing or re-index the cam he might let you slide on that one.

[mrc24x]

I say add the cam while you're in there and just take the 6 points..... If you want to keep the stock cam then find an aftermarket DIRECT replacement timing set. If it meets the criteria below then your safe. (it's from the PT rules but it's the same)

 

"For purposes of NASA PT points assessments, the term OEM will be defined as follows: Any part that is identical in size,

shape, and functional characteristics compared to the part that originally came on the vehicle, from the manufacturer, as a

standard feature of the base model as it is listed in section 5.2 Base Classifications (factory options and specialty model parts

are considered non-OEM) or is listed as a standard replacement part by the OEM manufacturer. Some parts that are

produced by aftermarket manufacturers as generic replacement parts may not require a points assessment provided that: they

are the same size and shape, and have the same functional characteristics as the OEM part, and that they provide no

significant improvement in performance, longevity, or reliability. If you have any questions about the modification points,

consult your PT Director. Errors and omissions could result in disqualification and other penalties."

[Aardwolf]

Yeah I don't intend to advance or retard the timing, just replace the failing chain. So I'd be OK to not take the points. Thanks guys!

 

Another question I have is about the adjusted power weight ratio. For TTC it says 12 to 1. I'm not super clear on this, does the rule mean I have to have more power the 12 to 1 or less then 12 to 1? For example if I added a cam it would add considerable power, perhaps putting my ratio around 10.8 to 1. Would that mean with the cam change I'd have to be in TTB which lists 10.25 to 1?

[kbrew8991]

you've got two limits to watch out for - staying under the points cap and staying over the adjusted hp:weight ratio.

 

The excel sheet that Mike Uhlinger built makes it really easy to figure it out - just put in the numbers and check the boxes that apply to your car. You can also use it to keep track of the points portion of the classing too, just check the boxes, pick the proper drop-down values and enter the numbers for your car as needed

 

http://www.westcoasthc.com/ptpoints.xls

[mrc24x]

If you are close on PW/WT you can run a little heavy and/or use 275's or smaller to get a little breathing room:

 

6.2.5 Modification Factors for “Adjusted” Weight/Power Ratio

The “modification factor” listed after each item below is added or subtracted from the actual

measured wt/hp ratio to determine the “adjusted” wt./hp ratio that determines vehicle legality in

each TT class.

Body Type: 4-door Sedan or 5-door Wagon = +0.4

Transmission: Dog-ring/Straight-cut gears (non-synchromesh) = -0.2

Sequential/Tiptronic-like/paddle shift/semi-automatic = -0.2

Drivetrain: AWD = -0.5

FWD = +1.0

Tires: Non-DOT approved tires = -0.75 (VRL & GAC Hoosiers see App. B)

Size 275 to 250 (or 10.5” to 9.6” for non-DOT approved) = +0.4

Size 245 or smaller (or less than 9.6” for non-DOT approved) = +0.8

Competition Weight:

Equal to or Less than:

3200-2800lbs 2750-2350lbs 2300-1900lbs 1850-1450lbs

3200 lbs -0.05 2750 lbs -0.5 2300 lbs -0.95 1850 lbs -1.4

3150 lbs -0.1 2700 lbs -0.55 2250 lbs -1.0 1800 lbs -1.45

3100 lbs -0.15 2650 lbs -0.6 2200 lbs -1.05 1750 lbs -1.5

3050 lbs -0.2 2600 lbs -0.65 2150 lbs -1.1 1700 lbs -1.55

3000 lbs -0.25 2550 lbs -0.7 2100 lbs -1.15 1650 lbs -1.6

2950 lbs -0.3 2500 lbs -0.75 2050 lbs -1.2 1600 lbs -1.65

2900 lbs -0.35 2450 lbs -0.8 2000 lbs -1.25 1550 lbs -1.7

2850 lbs -0.4 2400 lbs -0.85 1950 lbs -1.3 1500 lbs -1.75

2800 lbs -0.45 2350 lbs -0.9 1900 lbs -1.35 1450 lbs -1.8

Equal to or Greater than:

3300-3500lbs 3550-3750lbs 3800-4000lbs 4050-4250lbs

3300 lbs +0.05 3550 lbs +0.35 3800 lbs +0.65 4050 lbs +0.9

3350 lbs +0.1 3600 lbs +0.4 3850 lbs +0.7 4100 lbs +0.95

3400 lbs +0.15 3650 lbs +0.45 3900 lbs +0.75 4150 lbs +1.0

3450 lbs +0.2 3700 lbs +0.55 3950 lbs +0.8 4200 lbs +1.05

3500 lbs +0.3 3750 lbs +0.6 4000 lbs +0.85 4250 lbs +1.1

Note: If between 3201 lbs and 3299 lbs, there is no modification factor.

[Aardwolf]

So my points must fall in the class then my adjusted pw/wt falls in also. For example to be in TTB I must stay from 8.7 to 1 and 10.25 to 1? That's a range in HP from 322 to 379 at 3300 pounds.

 

I think a cam change will put me over 322.

 

Matt, I've got a super ram to install plus ported stock heads.

[Greg G.]

No, you must be over 10.25:1 to be in TTB. The range you posted above qualifies the car for TTA (assuming that the points don't add up too high and put you over the top).

[mrc24x]

So my points must fall in the class then my adjusted pw/wt falls in also. For example to be in TTB I must stay from 8.7 to 1 and 10.25 to 1? That's a range in HP from 322 to 379 at 3300 pounds.

 

I think a cam change will put me over 322.

 

Matt, I've got a super ram to install plus ported stock heads.

 

 

Your example would put you in TTA if you are under 10.25 but above 8.7 (like Greg said above).

 

My guess is that your Superam, ported113's AND a cam would put you ~335 rwhp. I'm also guessing for the example that you will be 3300lbs after a session w/ you in the car.

 

Ex: 3300 / 335 = 9.85 +.05 from the weight adjustment = 9.90 (TTA territory)

 

Unless you run 275's = 9.90 + .4 = 10.3 Safely in TTB.

 

Make sense??

[Aardwolf]

Got it! Thanks.

 

For those modification factors, have they thought of giving + .4 or something for using an auto. I'd like to use a five speed manual but with my injured back I stick with an auto. This is an old style auto, 1988 without paddle shift.