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Posted by: FastFroggy Apr 29 2024, 12:40 PM

Hello all,

I previously ran HPDE events and autocrosses prior to my engine issue. I am now wrapping up my 914-4 rebuild and just passed my SCCA Licensing Class. Really enjoy running the car. Would like to see if there is an SCCA class I can fit it, but looks tough. Looking for guidance on the best path forward given my stated priorities:

1. SCCA regional level minimum
2. Extent of further modification needed
3. Relative competitiveness in class

My car:
a. 1973 914-4 with up to date safety items(Cage, extinguisher, seats, harness, etc)
b. 2.0l stock internals
c. race headers
d. large bore twin carbs
e. 5 lug conversion
f. 911 1973 rotors
g. 911s calipers front
h. fiberglass fender flares

Please PM me with feedback. Thanks, GregM

Posted by: GregAmy Apr 30 2024, 07:16 AM

Oh boy, big long discussion...but let's start with WELCOME!

Second item is...download the General Competition Regulations:

https://www.scca.com/pages/cars-and-rules

Your first concern is safety: what kind of cage desgin do you have? What was it logbooked for? Different categories have different requirements. No fuel cell or fire system? Limits your options. No dash bar? Limits your options.

What tires?

At first glance at your specs, I'm not seeing an easy answer for there your car fits, but we'll find something. Some mods, such as fender flares and suspension and brake upgrades, limit your access to the lower-end classes.

The general options:

- Improved Touring. DOT tires, but requires stock induction, stock body, stock wheel bolts, stock brakes and suspension design.

- Production: slick tires and allows limited body mods, but requires fuel cell and fire system. Would have to review the 5-bolt to see if it's allowed but brakes are Ok with a weight adder. Carbs maybe OK depending on engine size.

- Grand Touring: can probably do all that but you'd require a fuel cell, fire system, and you'd get your ass handed to you by immensely faster cars.

Let's look at regional options. If you're in Ann Arbor then you're probably a member of the Detroit Region, thus Great Lakes Division (I think I found you in the membership directy...racingrabbit...)

https://www.gldscca.com/road-racing

As with many divisions, GLDiv has some local regional series, described here:

https://drive.google.com/file/d/1K-9vOMhWmVuUk7IXIE5Z5O0xae0EJ-9v/view

I see that GL Div has both ITE and Super Production.

ITE is generally cars that were built for an old endurance series like IMSA Firehawk, but NEDiv, where I am, are very loosey-goosey with the regs; as long as you're on DOT tires and meet Improved Touring safety regs (basically cage and fire bottle), no one cares. ITE requirements are described in the above link.

SPU (under 2.5L) is similar in that it must meet Production safety regs and can run slicks. SP regs are described in the GCR, Section 9.1.C. This will require a fuel cell, dash bar, and fire system.

Note that neither of these classes would be eligible to take you to the Runoffs (which is at Road America this year). But you can race regionally.

I suggest given the level of mods you've done to your car already, SPU is the droid you're looking for. But you'll need to look into a fuel cell, fire system, and possibly upgrading the cage.

Glad to answer questions as needed, and find someone in your area who can help shepherd you through this.

Greg Amy
SCCA 110138, member since 1984
Full Competition License since 1986
National Scrutineer
National Steward
Certified F&C
Registrar
Time Trials Admin, Manager, Coach
TNIA Manager and Coach
Comp License Instructor
Race Data Tech
Purveyor of all things beer...and all around OK guy

Posted by: GregAmy Apr 30 2024, 08:14 AM

Some updates.

I'm reviewing the regs, and the following is the fuel cell requirement (GCR 9.3.26):

"All cars must be equipped with a safety fuel cell complying with these specifications, except for Touring, B-Spec, C-Spec, Spec Miata, Improved Touring, American Sedan restricted prep, production-based Vintage cars, and cars where the stock fuel tank is located between the axle center lines and within the main chassis structure (i.e., frame rails, etc.)."

I believe the stock fuel tank meets the highlighted allowance and thus should not re required.

If you choose to go with a cell, it's generally installed in the front trunk (that's where it is on my historics racer). But if I were feeling really flush...I do like this setup:

https://patrickmotorsports.com/products/fuesa914pms

As for other "safety" mods...

Roll cage: you'll need two tubes going forward to the firewall, and a lateral brace between the front legs "at the approximate level of the dashboard."

And what tires are you going to run? My car has a long history of oil starvation when we started to go to Hoosier tires in the early-00s, tossed a couple engines in the process. The resolution was dry sump. If you're going to run anything stickier than 200TW tires you might give that some thought (and I personally do not perceive an Accusump as an acceptable long-term solution to address that design shortcoming).

Posted by: FastFroggy Apr 30 2024, 11:03 AM

Thank you GregA,

Lots of good info. I have been continuing to read and re-read the GCR as well.

I am still trying to interpret the EP rules, for which I have some specific questions. I'll PM you to continue the discussion if that is ok.

GregM

Posted by: ChrisFoley Apr 30 2024, 12:32 PM

Regarding fuel cells, my Production car custom fuel cell is for sale. (all the race parts on my car are for sale, in fact)

Posted by: BillJ Apr 30 2024, 12:39 PM

If going racing (circuit course not autox) then get a cell. Its a safety item. You wont regret it when you hit something and your fuel stays inside the rubber bladder of your compromised tank. Instead of dumping all over your passenger cabin and you.

Can you share pictures so that you can get best advice?

Posted by: GregAmy Apr 30 2024, 02:31 PM

You're welcome. Let's keep the discussion public so others can chime in...?

Eprod is a fun class, but it's a motor class...and a money class. For reference, I was racing a 250whp FWD Civic in EP last couple years, and I was mid-pack. A fully-built bad-ass BMW Z3 is the ticket right now, closely tailed by a Lotus Super 7 (or is it a Caterham?) that weights nothing. I'm not say you won't have fun racing in EP, just set your expectations accordingly.

BTW, Chris, above, has a bunch of race car stuff for sale. This was an FProd 1.8L and they were competitive in the 90s. Today, FP is dominated by Miatas and FWD Hondas.

Only concern I have with your stated specs is the 5-bolt conversion; I don't think that's compliant. Will anyone GAS, especially in regional racing? Probably not. But here's the other argument: "914-6 calipers & discs allowed". Does that mean you vcan convert to 5-bolt? It sure implies it...

Also note you have to run 38mm venturis.

I'm pretty sure the Fiberglas flareds are allowed, given fenders can be replaced with alternate material and flares are allowed. 15x7 wheels max.

have you pursued your Novice Permit yet? I checked the records and it's not listed. If not, we need to work to get you a safe car so you can get on the track.

GA

Posted by: FastFroggy Apr 30 2024, 04:19 PM

BillJ, you bring up a very good point. The 914 is not ideal for its fuel tank proximity to cabin ventilation. I think at a minimum vent block-offs.

Reminder on the objective:
- local track Waterford Hills
- competitive at Regional Level

To fill in some of the background on the car:

Previously ITA logbook(lost to time, with passing of owner), bought in Colorado.
-8 pt cage, Nascar-ish door bars ( will be adding a lower diagonal across the main hoop based on 914 racer friend experience)
-rear chassis stiffening
-15in wheels 7"/8"
-external oil cooler / accusump
-deep sump
-2.0 l stock block for now
-44mm dual carbs
-5 lug conversion
-S caliper front
-1973 911 front and rear rotors

https://youtu.be/5xtbZOsLZWA?si=pjlslyJ7yapuDNB_

GregM

Posted by: brant Apr 30 2024, 07:01 PM

You should probably show us a picture

I might even know some history on it
The problem is the big bore

Posted by: GregAmy Apr 30 2024, 08:11 PM

If you look on the right side vertical leg of the main hoop, there should be a number stamped into the rollcage. If it was caged in Colorado Region it should start with 8 or 08.

Regardless, get that number for me and I can investigate its history. We might be able to re-logbook it with that number. - GA

Posted by: ChrisFoley May 1 2024, 04:48 AM

EP will restrict you to 7x15 wheels, 40mm carbs, and M calipers.
5 lug not a problem.

Posted by: GregAmy May 1 2024, 06:50 AM

Chris, we have a new brake rule in Prod, think it came in 2023...the alternate brakes listed on the spec line are allowed without penalty, but now you can add up-to-4-piston calipers and unrestricted rotors for a +2% weight adder (must fit within the allowed wheels).

I think I'm with you on the 5-bolt conversion though it certainly doesn't explicitly come out and SAY you can do it...and the baseline premise of the category is 9.1.5.D.1:

"An addition, modification, substitution or removal, must not be made unless specifically authorized."

In this case, it explicitly allowed the /6 calipers and rotors, so the onyl reasonable way one can do that is with a 5-bolt conversion. So I support it.

I'm just curious if the CRB is aware one is 4-bolt and teh other is 5-bolt...

BTW, I've tried to get the 2L Limited Prep 914 moved from FProd to HProd but they're fraidy skeered of it (despite several 2L Golfs being in there). I don't see the 2L being able to compete with the Miatas in FP. So if I were serious about racing a 914 in Prod I'd build a LP 1.8L for HP and convert it to Microquirt. - GA

Posted by: FastFroggy May 1 2024, 06:54 AM

Thanks for all the insight. Really appreciate it.

- Have an SCCA Race Novice Permit.
- PM'd Chris about a fuel cell
- Stamp on cage is 50-07009
- Looking at the cage, I will need to verify about the upper diagonal. Probably to add with the lower.
- yep. 7x15s, M Calipers and 40mm webers on the list
- photos to follow in next day or so. reestablishing my drop box/photobucket accounts

Question: PCR indicates only rotor diameter with no mention of solid or vented. are vented rotos ok as long as they meet the diameter? or is of a weight penalty?

Posted by: GregAmy May 1 2024, 07:49 AM

Do you have your schools signed off yet? What's the plan?

- Stamp on cage is 50-07009

That was issued by Region 50, Utah Region. Their web site is sparse, but you can send them a note to utahscca@outlook.com and see if anyone can identify that logbook number. If they can, we could possibly re-issue it with that old number.

https://www.utahscca.com/

However, except for posterity's sake, there's not a lot of usefulness versus getting the car re-inspected and issued a new logbook. It would be cool info to have but is not required.

Question: PCR indicates only rotor diameter...

I think you mean GCR (SCCA or do you mean Porsche Club)? With SCCA, you can run one of two brake configs in EP:

- "Front “M” calipers permitted, 914-6 calipers & discs allowed" (whatever size and config they are) with no weight penalty; or
- Any 4-piston caliper and any rotor that fits within the allowed 15x7 wheel, with a 2% weight adder (GCR 9.1.5.E.7)

Posted by: FastFroggy May 1 2024, 08:40 AM

Yes, I have my school signed off.

Plan is to have fun, race hard, be competitive. Target is to finish engine install and track ready by end of May. Make vintage event at WaterfordHills in late August. Investigating to run SCCA road race series.

Utah SCCA: I already contacted them a few years ago with no real feedback.

Yes GCR, which refers to PCR for Production Competitions Rules(i guess)

I need to check the front rotor specs, but at least the rears on a 914-6 were solids i believe. I run vented 911 rear rotors(aka 916 rear). Would it just be a 2% weight penalty or NOK?. Same question for front "S" caliper?

Posted by: ChrisFoley May 1 2024, 10:59 AM

914-6 has vented front and solid rear rotors. Using 914-6 front calipers/rotors requires use of 5 lug hubs - ie. 914-6 struts.
Old Prod regs allowed 914-4 front calipers at the rear. I kept stock rear calipers, but gutted the parking brake and manual adjustment components.

Posted by: FastFroggy May 1 2024, 02:51 PM

batter batter swing..... on photos. Will take a day or two.

A few side notes:

I was looking at old photos, and I was wrong. Previous car markings show that it was in ITE-U.

Will be studying to see how different prep is a and local competition.

Posted by: Charles Freeborn May 3 2024, 08:21 PM

... then there's vintage. You'd be in VP2 I believe with the 2.0L

Posted by: brant May 4 2024, 07:32 AM

what is the displacement again?
don't think you have said..
gather its bigger than 2.0

that is your largest barrier most likely.
brant

Posted by: GregAmy May 5 2024, 07:04 AM

For historics racing? Show me the last time a car was scrutineers to the regs.

And when you do, and you like that? I'll suggest it's WICKED too "srs bzns" and I'd strongly suggest you stay with the https://tgadrivel.blogspot.com/2022/11/on-sccas-participant-insurance.html.

Historics racing is a whole 'nother attitude from amateur club racing. At least, it's supposed to be...

GA, who does both, for their individual goals and attitudes.

Posted by: brant May 5 2024, 09:24 AM

No matter what sanctioning body
Classes often include displacement in their formulas

No matter testing displacement or not
Honestly of the applicant I and integrity of the persons word is important

Posted by: Charles Freeborn May 5 2024, 09:03 PM

Here are vintage sups for our region. A 914 would be far more competetive as a 1.8 with 2.0 heads in VP1. Mine is a 2.6 so I'm automatically in VP2 (for now at least).

https://static1.squarespace.com/static/655959e85f8fa21d478bcefa/t/65b308bdb2ff6c2c1823a44d/1706231998345/Vintage+Supplements+2024.pdf

Posted by: FastFroggy May 6 2024, 05:38 AM

Just noticed that I missed a few questions.

a. yes, current engine is a 2.0L (19xx cc)
b. Im fin to do Vintage, but looking to get my full SCCA license asap. (only just got my novice permit.)


Pictures available via link.
https://drive.google.com/drive/u/2/search?q=sharedwith:public

Posted by: FastFroggy May 6 2024, 03:24 PM

Thanks again for all who are contributing.

Been reading up on the GCR in chunks so still do not have a full view of all class details.

EP sounds great for a local and Division level, but to get legal need some more part downgrades ( IE Carbs, Wheels, Brakes).

Based on this forum discussion, my initial concern about meeting class rules, I am a bit more focused on improving safety. I am willing to spend a bit on that.

I may be even less competitive, but at my home track I do not expect it will matter much, I am considering to class the car in GT3. I would need to get a fuel cell, but I think that is it.

Thoughts?

Posted by: Charles Freeborn May 6 2024, 09:06 PM

Your SCCA license will work for pretty much any amateur club race, vintage included. There is a strictly vintage SCCA license, but aside from lower cost I don't see much reason for that.
EP is a veny competitive class. Lot's of 3 series BMW and other more modern OHC cars. The 914, with it's pushrod engine will have trouble keeping up. You don't say what your home track is, but that's a big factor too. In a tight technical race you'll be in the hunt. If it's flat and fast not so much. Equally important as the engine is the gearbox and how it's set up. You need to maximize the limited power you have to work with. Building Porsche transmissions is not cheap either..
For now, get your license, learn the car get as much seat time as you can, race or hpde and go have fun. Let the racing unfold at it's and your pace.

PS I'm not able to see your pics. The link takes me to my google drive.

Posted by: GregAmy May 7 2024, 07:09 AM

Utterly uncompetitive nationally, but you'll still have fun at home. Amd no one will care about any mods that may be non-compliant (which may be none).

I'd need to see your cage, but you may be required to install two stubs from the front legs to the firewall, plus a lateral "dash" bar. Kill switch, window net, fuel cell, fire system required. Up to date harnesses, of course, and a good racing seat. Brake lights. Rain light, if your stock taillights are disabled. Disable steering lock. Tow hooks each end.

I'm drawing a total blank here but are 914 windshields bonded in? Rubber-installed windshields need windshield retention clips, bonded windshields do not.

We need to hook you up with a local inspector to start the inspection process and give you tips on what needs to be done. Send an email to the road racing director of Detroit region to find out to who to work with: http://drscca.org/race/

And I strongly suggest some kind of either dry sump or Accusump (former preferred). - GA

Posted by: FastFroggy May 7 2024, 07:24 AM

Hope this finally works, will get photos of the front cage and rear cage points later today. All connected in full 8pt cage.

Posted by: GregAmy May 7 2024, 08:33 AM

>>> I'd need to see your cage...

Looks good from here.

>>> Kill switch

Installed. Ensure everything goes through it, and run the car and flip it to see if the car dies. That's how we test them.

>>> fire system required

I see it's there. Ensure the bottle is up to spec.

>>> Up to date harnesses

In 2017, SFI changed from tags listing the manufacturing date, to tags listing an expiration date. The old ones were good for five years with SCCA, the new ones two years. Yours appear to be the older manufacturing-dated SFI; if that's correct then you'll need to replace your harnesses.

However, if yours actually have another tag that gives an expiration date, ensure they're good through 2024.

Spend a little more for the FIA ones. They're good for five years instead of two.

>>> a good racing seat

Those look good. Give 'em a good shake and ensure they're "securely mounted".

A back brace is not required by SCCA, but may be required by other orgs.

Note that if you run with the top off, you must pass "the broomstick test" and use arm restraints. That mean the top of your helmet must be two inches below a broomstick (or whatever) handle placed across the top of the rollbars.

Ironically, if you install the plastic targa top, your helmet can actually touch the top and no one cares. Don't ask me why...

>>> windshield retention clips

Yours seem to comply.

>>> window net, fuel cell...Brake lights. Rain light, if your stock taillights are disabled. Disable steering lock. Tow hooks each end.

Check you comply with those.

Posted by: moto914 May 7 2024, 10:20 AM

Great thread.

Posted by: FastFroggy May 7 2024, 12:47 PM

Thanks for the clarity of feedback. I have a follow-up question.

My read of the GCR seems to contradict my understanding. Arm Restraints are required for the Targa, but it seems to indicate that window net is also required in addition. Is that correct?

Posted by: GregAmy May 7 2024, 01:27 PM

It is not correct. Once you remove the targa top, you become an "open top car" and all that that implies.

A targa top car, minus the top, is considered open top and requires arm restraints. With the targa installed, it's closed top and requires a window net. There's nothing against running both, but with arm restraints, a window net becomes redundant (its purpose is to keep your arms inside the car).

I've requested that SCCA explicitly define open top versus closed top, but they refused. Dunno why.

My car carries both configs, depending on how I prefer to run it (or, for example, I am forced to run mone with the top closed at the Lime Rock Historics, otherwise they put me with the sports racers instead of "tin tops"...)

Posted by: ChrisFoley May 7 2024, 02:41 PM

IIRC, in the production classes, if you remove the roof you also have to remove the windshield and rear glass. Otherwise the roof needs to be secured with bolts rather than latches.

Posted by: groot May 7 2024, 05:38 PM

You're local to me... and if I recall, you may work in the same building as I do. I'll be in the office tomorrow before heading to Spa. Look me up and swing by.

Posted by: brant May 7 2024, 05:46 PM

Nice to see you here kevin

Posted by: groot May 7 2024, 05:54 PM

Thanks, Brant... I stalk every once in a while... been crazy busy, but everyone is. I see Erik often... always good the catch up with him.

Posted by: GregAmy May 8 2024, 06:53 AM

The whole open-top/closed-top thing is a PITA and SCCA refuses to clearly define it. I asked last Fall for a explicit definition to be added to the GCR Technical glossary but it was denied; I suspect it's because of some conflicting prep regs (which is why I requested it) and they don't want to step into that pile.

The only reference I can find to the intent is GCR 9.3.18, Driver's Restraint System, "Arm restraints are required on all open cars including open Targa tops, sunroofs and T-tops."

This implies, but does not define, that a targa car with the top off is "open" (which requires arm restraints) and with it on it's "closed" (which requires a window net).

GCR 9.3.17 refers to Detachable Panels/Sunroofs, implying that targa tops must be removed, however it also states, "Movable or removable metal or composite panels in the roof may be either removed or positively secured in the closed position." But then, "Any openings in the roof resulting from the removal of a panel must be covered..."

"Well, which is it, young feller? You want I should freeze or get down on the ground?" (name that movie reference...)

The Production regs allow, but do not require, cutting of the windshield and removal of the rear glass (9.1.5.E.9.a.8.A, "Open cars may remove the windshield glass, door window glass, quarter window glass, rear glass, vent glass...If removed, a replacement windshield must be installed...) This is the regs that was intorturated back in the 70s to "replace" the windshield and frame with the now-well-known "Ginther Windshield".

If would seem, by general practice, that SCCA thus considers targa-top-equipped cars as open top for the purpose of this reg, as no one that I'm aware of has ever been bounced for Ginthering a Porsche 914. 'Specially since Ginther was probably the first one to do that.

So if you pop the targa top, whether or not you choose not to cut the windshield, then you're an open car (and its associated regs requirements).

Unsurprisingly, the GT regs say nothing about open top versus closed top cars. The inconsistency is palpable...and frustrating. But GT regs are so permissive now that it doesn't matter, no one will care.

Frankly, unless you're willing to go the whole Ginther route, it's preferable from an aerodynamics perspective to leave the roof on. But given the really bad aero we have with that rear roof deck, if you get serious about aero you'd want to go full Ginther.

I think a Ginthered 914 looks cool. I keep wanting to do that to mine but Chris keeps talking me out of it...and points me to the chassis he has for sale that's already done.

EDIT: if you're interested in the aero, this is an interesting discussion: http://www.cassidy-online.com/porsche914/aerodynamic_aids/index.html

Posted by: gms May 8 2024, 09:36 AM

you might want to check out
https://vscda.org/
and
https://www.mcscc.org/

these are two local clubs that have great racing events and both have vintage classes

Posted by: FastFroggy May 8 2024, 11:57 AM

GregAmy, Somewhat glad to hear I was the only one getting confused on the subject of open/closed and window net/arm restraints. I will be getting a new logbook, the window net is something I will need to iron out.

For now my biggest hurdle is the fuel cell. Working on that.

Thanks again for all the insight.

Posted by: Charles Freeborn May 9 2024, 10:43 AM

Fun looking car. Similar to my last one built by AJRS for a now gone GT5S class of PCA racing. You'll have to comb the GRC to see if all the body and suspension / brake mods kick you out of a P class - GA will be the best to comment on that. If so you'll fall in a "catch all" class of GTx or SPU. SCCA vintage VP2 is still an option, but against up to 3.0L cars you'll get spanked. Drop the engine to a 1.8 and run in VP1 and you'd be very competitive. You could also just run in VP1 and see if anyone protests. As an novice i doubt they will as the little 510 datsuns are screamers. Good luck beating them... Have fun with it, but yes, absolutely get a fuel cell into it. I also highly recommend an oil pressure activated fuel pump cut out switch. If the engine dies it shuts off the fuel pump. The car starts from what's in the carb bowls. You can wire in a momentary over ride switch if the carbs are empty (sitting / stored long enough for carb bowls to evap)

Posted by: infraredcalvin May 10 2024, 09:18 PM

Raising Arizona

@http://www.914world.com/bbs2/index.php?showuser=15565

Posted by: GregAmy May 11 2024, 05:33 AM

Posted by: Charles Freeborn May 11 2024, 10:12 PM

I couldn't place it. Best guess was a western a la Clint or similar....
Haven't seen Raising Arizona in some years. Gonna have to queue that up sooner than later.

Posted by: FastFroggy May 16 2024, 09:02 AM

Progress from Saturday: engine and trans finally back in the car



Progress from Wednesday: Carbs cleaned and verified

Posted by: FastFroggy May 16 2024, 09:03 AM

Does anyone know where I can find the missing choke fixing screw and nut?

Posted by: FastFroggy May 16 2024, 09:03 AM

update from this weekend:

Still needs tidying up and a new battery, but ready for first start

Posted by: FastFroggy May 16 2024, 09:03 AM

oops..

Posted by: Charles Freeborn May 18 2024, 08:53 AM

https://www.carburetion.com/

Posted by: ChrisFoley May 18 2024, 12:47 PM

I have one in my hand

Posted by: FastFroggy May 20 2024, 06:46 AM

Thanks Chris, PM me a method of payment.