17 replies to this topic

[dcostello]

I am looking for any lightweight hf parts to move over to an SI. Looking for plastic valve cover, door panels, interior carpet, front and rear bumper supports, rear brake dust shields and anything else that might have a weight advantage.

I am competing in SCCA autocross running in the CSP class. The car is a trailer queen and only sees the road when it has to. The car is rather prepped so it has seats, the sunroof has been removed, a smaller battery, no rear wing or rear wiper. The car currently and legally weighs 1651 lbs. slightly wet. Any suggestions to get more “legally” out of the car is greatly appreciated. One more question: has anyone heard of a Watts linkage for these cars? Can it be done to the rear axle location without changing the mounting points per the SP rules?

Just as an FYI my other planned changes are removing the battery tray, radiator fan, lighter muffler, maybe a lighter intake tube (fiberglass), and more cold air. Any other suggestions to get these things back being competitive NATIONALLY in CSP would be appreciated.

Thank you,

[badpenny]

I am not 100% sure, but have you thought of getting an hf flywheel and starter?

That us unless you have not already lightened the flywheel.

[savestheday]

I have a clock delete, plastic valvecover, and maybe a antenna delete if you are interested. I could ship them thursday.

[DSK 86CRX]

i have the ac delete tube if you'd be interested in that, im not sure what else is wanted off the hf, but mine is an hf and im getting rid of a lot of parts and putting si parts on so let me know what else you need, i have 2 hf 13in wheels also, with slicks mounted to them

[EPcivic]

Don't forget the HF axle shafts (hollow), front brakes (solid), and the rear beam axle assembly (smaller, lighter, and has the aluminum drums).

I don't see how you could do a Watts linkage within SP rules. It requires a frame mount in the middle of the car, and the panhard bar pickup is far to the driver's side.

The big hitters for weight are the flywheel/clutch and the exhaust manifold/system. ITB's or sidedraft carbs are lighter than the OE plenum. 84-85 body parts are lighter than the 86-87 ones. Really, I think it's easier to start with an 84-85 HF and convert the drivetrain than to swap over all the light parts.

1651 doesn't sound too far off to me. The lightest ones I have seen are just under 1600lbs, so you don't have too far to go.

-Chris

[87sivtec]

The actual rear axle is smaller/lighter? I didn't know that. I did know there is no rear sway bar inside it.

Don't forget the HF axle shafts (hollow), front brakes (solid), and the rear beam axle assembly (smaller, lighter, and has the aluminum drums). 

I don't see how you could do a Watts linkage within SP rules.  It requires a frame mount in the middle of the car, and the panhard bar pickup is far to the driver's side. 

The big hitters for weight are the flywheel/clutch and the exhaust manifold/system.  ITB's or sidedraft carbs are lighter than the OE plenum.  84-85 body parts are lighter than the 86-87 ones.  Really, I think it's easier to start with an 84-85 HF and convert the drivetrain than to swap over all the light parts.

1651 doesn't sound too far off to me.  The lightest ones I have seen are just under 1600lbs, so you don't have too far to go.

-Chris

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[kakabox]

The actual rear axle is smaller/lighter?  I didn't know that.  I did know there is no rear sway bar inside it.

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This is from my build thread; http://www.redpepper...ndpost&p=212569

...after pulling out the ‘teg’s rear disc brake axle, I was able to compare it w/an ’86 CRX HF axle:


…the ‘teg’s axle is the top one.

Here are some numbers:
’87 ‘teg axle w/o brakes/brackets/hubs, w/spindles and internal torsion bar: 40 lbs. …axle diameter: ~2.5”

’86 CRX HF axle w/o brakes/brackets/hubs, w/spindles: 27 lbs. …axle diameter: ~2.2”

Outboard face of LHS stub axle flange to outboard face of RHS stub axle flange distance: 50 11/16”…it’s the same dimension for both ‘teg and HF (and I assume all 1g/3g cars).

AFAIK, the 'teg axle is identical to the 1/3g Si axle with exception of the internal stabar diameter.

[dcostello]

Thank you for all the replies! I will try to touch everyone with this from top to bottom.

badpenny - already have 7 lb aluminum flywheel.

savestheday – have done the clock and antenna delete definitely interested in the plastic valve cover. Please post or PM me a price.

Dsk_86CRX – I am not sure if I have the ac delete but I will take it to have a spare. Please post or PM me a price. On the wheels I am currently using 13X8 pannasports with Hoosier A6’s, sorry and thank you.

EPcivic – I have the hf half shafts and aluminum drums. I actually have an hf rear axle but I made the panhard bar mount adjustable which has since been determined as illegal in the class so I need a fresh hf rear beam axle. If you want an HF rear beam axle with an adjustable mount I have one. I do have a dc sports header on there now that replaced a lightspeed header. I believe the next step would be to get a lighter exhaust tubing and custom build one. I am also thinking about replacing my muffler with a hayabusa “lighter” muffler terminating behind the driver. On the intake side it is mostly stock because I am figuring about $3,000.00 to go electromotive with intake. The CRX is an 85 and I would go get an HF if I could find one but I am not sure I can. Oh I almost forgot. I am not sure I want to use the hf front brake rotors just for safety. I am thinking cross drilled will work in that area. Any thoughts on that would be appreciated.

Please keep items coming because I am in Omaha NE and parts are really scarce. I hit 3 local – “u-pull it’s” and found one civic and one crx SI. It has been a few weeks so I will be heading back soon. None are in the paper. Thank you again.

[duner]

disclaimer im not sure what all is legal and not in that class. but if you have the carpet in, take it out and pull out all of that insullation/sound deadener. that crap weighs a lot!

other parts i am thinking of (may be mentioned already) and some are totally obvious, but easy to overlook:

hf connecting rods are lighter. but some say weaker too....
HF alum drums
get an alum crank pulley
hf/dx center console
empty/throw away washer fluid and motor
get rid or your rear wiper/motor
remove rear spoiler
remove any wiring you can
if you go with hf discs get their hubs (you have to in order to do it)
hf half sized radiator
remove heater blower motor (if not needed for defogging)
take off rear hatch supports
remove speakers
you said you removed the sunroof, what about its motor?
get a lighter aftermarket fuel pump
some guys dont run a brake booster, they say with no loss in performance or feel
get a smaller sized battery. MrD sells some tiny lightweight racing ones
thin out the padding of the headliner if you cant toss it
replace key ignition with button or toggle switch
remove heater control (again if not needed)

again, i dont know your class' rules ans some of these are a little ridiculous sounding, but every ounce lost is some thing. think of it, bicycle racers look at weights down to tenths of grams.

[crxls]

im not sure if it saves any weight but the HF steering rack has a different ratio. i would assume it saves weight or they wouldnt have made it Hf specific....

[duner]

im not sure if it saves any weight but the HF steering rack has a different ratio. i would assume it saves weight or they wouldnt have made it Hf specific....

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it is a "quicker" ratio...meaing it turns more at the wheels for the same rotation on the steering wheel. so it is more responsive.

[lxndr]

I have an HF steering rack and an HF rear axle with a lightspeed 19mm external rear sway bar that I will be selling soon. The HF axle and 19mm sway bar combo is lighter than the stock rear axle with internal sway bar and more effective. PM me if interested

[dcostello]

disclaimer im not sure what all is legal and not in that class. but if you have the carpet in, take it out and pull out all of that insullation/sound deadener. that crap weighs a lot!

other parts i am thinking of (may be mentioned already) and some are totally obvious, but easy to overlook:

hf connecting rods are lighter. but some say weaker too.... - illegal
HF alum drums - Done
get an alum crank pulley - Great Idea
hf/dx center console - Great Idea
empty/throw away washer fluid and motor - illegal
get rid or your rear wiper/motor - Done
remove rear spoiler - Done
remove any wiring you can - illegal
if you go with hf discs get their hubs (you have to in order to do it) - Great Idea
hf half sized radiator - Done
remove heater blower motor (if not needed for defogging) - illegal
take off rear hatch supports - illegal
remove speakers - Done
you said you removed the sunroof, what about its motor? - Done
get a lighter aftermarket fuel pump - Great Idea
some guys dont run a brake booster, they say with no loss in performance or feel - Done
get a smaller sized battery. MrD sells some tiny lightweight racing ones - Done
thin out the padding of the headliner if you cant toss it - illegal
replace key ignition with button or toggle switch - illegal
remove heater control (again if not needed) - illegal

again, i dont know your class' rules ans some of these are a little ridiculous sounding, but every ounce lost is some thing. think of it, bicycle racers look at weights down to tenths of grams.

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Added comments above.

Thanks a bunch you for the ideas! It is very hard to find out everything about these cars unless you could talk to the actual designers to find out what they did. Everyone has their own experiences and pockets of ideas. My goal is to learn from others, apply my own ingenuity, and then drive the hell out of it

Good and bad, I will be weighing everything this year thanks to the Miata's

[crxbruddah]

it is a "quicker" ratio...meaing it turns more at the wheels for the same rotation on the steering wheel. so it is more responsive.

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Does the HF have a quicker ratio than the DX or just the Si?
Les

[duner]

Does the HF have a quicker ratio than the DX or just the Si?
                                                                                      Les

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from what i understand, both the dx and sia re the same; therefore the hf is quicker than both the dx and si