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PostPosted: Sat Dec 14, 2019 11:02 pm 
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Posts: 251
Protech Racing wrote:
I'm sure theyre worried about the quality of the add on link and fitment.

If it comes apart the axle flops out, breaks the drive shaft, tosses the axle with tires across the track , endoing up into the packed stands.
But really .The OE bits are known good value, they suck, but dont fall out . The add ons are fabbed by who knows who?
Lawyers and race cars.

Riiiight. You do understand what sarcasm is, right? If that were truly a concern they wouldn't allow the 3 link in the first place. Every car on the track has some work done by someone with a bigger, better idea. If safety was the concern we would all be driving showroom stock cars with airbags fully functional.


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PostPosted: Sat Dec 14, 2019 11:04 pm 
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Dan DeRosia wrote:
I like how the links aren't required to be OEM... so you could, say, sit and cut some "links" out of a piece of sheet aluminum or, hell, balsa wood... put couch foam "bushings" in with plastic bolts and it'd be legal.


I am going to use zip ties. I will use the big ones for an extra safety margin... :roll:


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PostPosted: Sat Dec 14, 2019 11:07 pm 
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Ian Green wrote:
I assume this is a slippery slope judgement. The rules are nice enough to let you do whatever for lateral control and torque control but if you could also eliminate part of the suspension then you may be able to make whatever geometry you want with whatever pivot points you want.


No, you can't at least not on the first gen RX7. Prep level 2 requires oem pickup points. The only OEM pickup points being used are the 2 lower ones for the rear axle. The uppers are extraneous with the 3 link.


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PostPosted: Sun Dec 15, 2019 9:26 am 
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Greg Amy wrote:
I see the modern Honda 130hp 16-valve DOHC 11.5:1 direct-injection 6800-RPM engine is perfectly acceptable in HProd, yet the legacy Volkswagen 91hp 8-valve pushrod 10.5:1 analog injection 5600-RPM engine is a threat to HP because it is two liters displacement.

They'd actually prefer you first prep the 1.8L 76hp engine to compete against the 91hp 3-valve DOHC Honda (with the Honda being 200# lighter) before they'll consider classifying the +15hp 2L version. So -15% hp and +15% poundage?

Okey doke. Thanks for your reponse.


So what power can the 1.8 make at the allowed CR and cam lift?
The low compression 1.8 in my son’s 86 Golf is something like 86 or 89 hp, but plenty competitive when built to the spec line.
To suggest that stock hp is a meaningful metric to compare cars with different engine architecture, chassis layout and allowed CR and cam is a bit inaccurate.

Of course the real issue is that we need a class between F and H if we intend to protect the competitiveness of the smaller motor H cars. We are still paying the price for the inappropriate actions of our BOD over a decade ago. This is an issue for the Mk3 Golf as well.

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PostPosted: Sun Dec 15, 2019 10:40 am 
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Location: Portland, OR
chois wrote:
Of course the real issue is that we need a class between F and H if we intend to protect the competitiveness of the smaller motor H cars. We are still paying the price for the inappropriate actions of our BOD over a decade ago. This is an issue for the Mk3 Golf as well.


Totally. There are no new H cars being made. Every B-Spec would be a G or maybe F. But if they keep getting classed as overweight H cars it won’t be long until the whole class is overweight cars.

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FP CRX Si


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PostPosted: Sun Dec 15, 2019 11:04 am 
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Ian Green wrote:
chois wrote:
Of course the real issue is that we need a class between F and H if we intend to protect the competitiveness of the smaller motor H cars. We are still paying the price for the inappropriate actions of our BOD over a decade ago. This is an issue for the Mk3 Golf as well.


Totally. There are no new H cars being made. Every B-Spec would be a G or maybe F. But if they keep getting classed as overweight H cars it won’t be long until the whole class is overweight cars.



Yes! Bring back GP! There are enough hated “tin tops” that G should be successful, while H will likely go away.


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PostPosted: Sun Dec 15, 2019 12:39 pm 
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Ok, challenge accepted. Bring back GP and let's see what HP can do.

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Hp-Lp Spitfire 1500 (for sale)
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PostPosted: Mon Dec 16, 2019 6:08 am 
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chois wrote:
So what power can the 1.8 make at the allowed CR and cam lift?

Dunno, and I'm not gonna spend my money to find out.

The full-prep FProd 1.8L engine I have in the car now (borrowed from Chris Foley because my 2L broke a crankshaft the week before the Labor Day Historics :boohoo:) is around 150 crank, per Chris. That's with big compression (12:1?), big lumpy cam, and a pair of Weber IDFs (GCR sez 38mm chokes). Damn that thing sounds nice at idle...my historics 2L was around 140 crank with 1mm overbore but with big valves, mild hand-porting, mild compression (9.5:1? instead of 10.5:1) and a comparable cam (.435 lift versus LP's .450 limit). And that's with dual 40DRLA Dellortos (38mm venturis). Recall, to be compliant the 1.8L HPLP 914 has to run stock valves and the single stock central-plenum throttle body of 44mm (I think), so that's a totally different induction system and no porting and no big valves (but a little more compression).

I would guess - and it's purely a guess, as I've never done it - that an LP-compliant 2L engine could get 140crank with development. So knock off your general Internet rule of 15% and let's call it 120 wheel.

Rumor has it the 1.5L Hondas are putting out around 130 wheel right now, at a 1900# base weight.

Since the 1.8L 914 in HPLP is currently at +200# over the Honda (IMO too heavy for that engine), I expect that a 2L, if it were classified, would have come in at a very very piggy weight (my chassis as-raced without driver is 1875# dry). But since I'm building a replacement 2L engine for Historics anyway my goal was to develop it to participate in HP and eventually toss real numbers at the PAC to hope for an appropriate adjustment. I would have driven it with ~300 ballast added (but easily removeable) and even if it never got a comp adjustment at least I still have an OK engine.

Instead, I'll develop the EFI for the street car and builid the racer's engine with the same "noncompliant" heads and Dellortos to go play with the vintage crowd. If the situation ever changes I can always use what I learned on the street car for the race car.

Greg


Last edited by Greg Amy on Mon Dec 16, 2019 7:22 am, edited 1 time in total.

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PostPosted: Mon Dec 16, 2019 7:06 am 
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Location: Dousman, WI
dhrmx5 wrote:
Dan DeRosia wrote:
I like how the links aren't required to be OEM... so you could, say, sit and cut some "links" out of a piece of sheet aluminum or, hell, balsa wood... put couch foam "bushings" in with plastic bolts and it'd be legal.


I am going to use zip ties. I will use the big ones for an extra safety margin... :roll:


See, I was figuring aluminum or carbon ones with plastic bolts would be kinda more... "visually sarcastic" if you get what I mean.


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PostPosted: Mon Dec 16, 2019 7:50 am 
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You guys would crap yourselves if you saw what's on my 1st gen there. zip ties and bungee cords may or may not be part of the recipe.

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Matt Blehm
Houston Region
EP 1st Gen RX7
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