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Last Post 22 Aug 2011 07:22 PM by  Andy Hollis
EF Civic in FSP?
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mrhongkongwong
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03 Aug 2011 02:16 AM

    Just curious why the EF Civic (89-91) can't be eligible in FSP like the EG Civic (92-95)?

    I would think the lighter weight EG Civic Trim's would be as light as the EF Civic's. Wheel base, power, suspension and etc seem to be very similar... Am I missing an advantage that EF's have over EG's from a Civic arguement?

    Tigermack
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    03 Aug 2011 02:17 AM
    QQ
    JBrettHowell
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    03 Aug 2011 08:03 AM
    mrhongkongwong wrote:

    Just curious why the EF Civic (89-91) can't be eligible in FSP like the EG Civic (92-95)?

    I would think the lighter weight EG Civic Trim's would be as light as the EF Civic's. Wheel base, power, suspension and etc seem to be very similar... Am I missing an advantage that EF's have over EG's from a Civic arguement?

    You would be wrong. The lightest EG's are about 100-150 lbs heavier than the lightest EF's. Narrower and lighter (especially when you are talking about less than 150 hp) makes a big difference.

    mrhongkongwong
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    03 Aug 2011 10:15 AM
    JBrettHowell wrote:
    You would be wrong. The lightest EG's are about 100-150 lbs heavier than the lightest EF's. Narrower and lighter (especially when you are talking about less than 150 hp) makes a big difference.

    Just to confirm, you are talking about a civic platform right? Currently in FSP, do you happen to know what the lightest EG's weight?

    Andy Hollis
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    03 Aug 2011 11:10 AM
    Hmmm...this becomes an interesting discussion now that the EG's get the VTEC motors and better trannys. Let's look at some data...



    Best EF weight-wise is the 88 base model at 1933 curb weight. And you'll want a Japan-built car to get that.



    Best EG is the 99 CX or VX at 2094. But this also gives a few more update-backdate opportunities between models due to the VX having some clever CRX HF-style weight savings.



    Track for an EF is 57.1 - 57.3, and EG is 58.1 - 57.7 (F - R).



    Width is 65.6 versus 66.9



    Best motor for EF is the Si rated at 108hp, while the EG can run the 125hp Si



    So each EF hp motivates 17.9 lbs (1933/108) while each EG hp pulls (2094/127) 16.5. That's an 8% difference. Given the many tire/tranny choices through UD/BD, hp becomes a valid simple analysis for thrust. Full dyno curves on built motors (IT is similar), multiplied through the gearing would be better, but you'll likely find similar #'s.



    Bottom-line: The EF is 1" narrower and 160 lbs lighter, so it will handle better, but the EG is faster off the corners. Seems like they could easily co-exist in the same class.



    --Andy





    JBrettHowell
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    03 Aug 2011 11:11 AM
    mrhongkongwong wrote:
    JBrettHowell wrote:
    You would be wrong. The lightest EG's are about 100-150 lbs heavier than the lightest EF's. Narrower and lighter (especially when you are talking about less than 150 hp) makes a big difference.

    Just to confirm, you are talking about a civic platform right? Currently in FSP, do you happen to know what the lightest EG's weight?

    About 1900 lbs...and that is taking just about every allowance possible.

    JBrettHowell
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    03 Aug 2011 11:14 AM
    Andy Hollis wrote:
    Hmmm...this becomes an interesting discussion now that the EG's get the VTEC motors and better trannys. Let's look at some data...



    Best EF weight-wise is the 88 base model at 1933 curb weight. And you'll want a Japan-built car to get that.



    Best EG is the 99 CX or VX at 2094. But this also gives a few more update-backdate opportunities between models due to the VX having some clever CRX HF-style weight savings.



    Track for an EF is 57.1 - 57.3, and EG is 58.1 - 57.7 (F - R).



    Width is 65.6 versus 66.9



    Best motor for EF is the Si rated at 108hp, while the EG can run the 125hp Si



    So each EF hp motivates 17.9 lbs (1933/108) while each EG hp pulls (2094/127) 16.5. That's an 8% difference. Given the many tire/tranny choices through UD/BD, hp becomes a valid simple analysis for thrust. Full dyno curves on built motors (IT is similar), multiplied through the gearing would be better, but you'll likely find similar #'s.



    Bottom-line: The EF is 1" narrower and 160 lbs lighter, so it will handle better, but the EG is faster off the corners. Seems like they could easily co-exist in the same class.



    --Andy





    With all due respect, then how do you explain the disparity in performance between the two platforms in ST?

    solo-x
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    03 Aug 2011 11:18 AM
    Some counterpoints....

    The D16Z6 motor is a VTEC motor. This means no cam gears. The D16A6 motor has no such limitation. In ST trim, my strong, but nowhere near professionally built D16Z6 made 125whp on a dyno jet. Andy's ST D16A6 made a touch more. I have it on good authority that an SP D16Z6 (or Y8 if you're using the EK chassis) won't make much more than 135whp. The D16A6 motors were in the 140 range before cam gears were allowed. With cam gears they should be close (or over) 155whp with more mid-range torque.

    Also, my ST EG, which to my knowledge was/is the lightest one out there, was just under 2100lbs. Andy's EF that year was around 1960lbs IIRC. In SP trim, I would expect an EG to get down around 1950lbs, and the EF to be knocking on high 1700's. The longer wheelbase of the EG will help with power delivery, but hurts agility.

    In short, the EF is going to beat the EG off the corners with more power, less weight, and more compact dimensions. I don't see the EF coming to FSP any time soon.

    All IMO, YMMV, tip your waitresses, completely unofficial, etc.
    mrhongkongwong
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    03 Aug 2011 11:43 AM
    Andy, do you have any data points between the two Civics? Would the weights be closer?

    How much of an advantage is the front lower control arms worth on the EG/EK Civic over the EF Civic?
    Andy Hollis
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    03 Aug 2011 11:54 AM
    solo-x wrote:

    In ST trim, my strong, but nowhere near professionally built D16Z6 made 125whp on a dyno jet. Andy's ST D16A6 made a touch more.

    No way any of my D16A6's have ever made "a touch more than 125whp". Not even close to that. I believe that you are remembering that there was not much difference in our midrange torque #'s, mostly due to the usual "torque hump" the A6 gets from the long-tube style CAI I use..

    --Andy

    mrhongkongwong
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    03 Aug 2011 11:56 AM
    JBrettHowell wrote:

    About 1900 lbs...and that is taking just about every allowance possible.

    IIRC, ST Civic's weight 1950-1980lbs, mine weighs 2070-2080. I'm not sure how much lighter the DX Trim would weigh but I could totally see both in the low 1900lbs range.

    Andy Hollis
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    03 Aug 2011 12:12 PM
    solo-x wrote:







    The D16A6 motors were in the 140 range before cam gears were allowed. With cam gears they should be close (or over) 155whp with more mid-range torque.







    +15hp for a cam gear on an SOHC motor? Seriously? Where do you get this from? The standard cam timing is about as optimal as it gets, unless you are simply lkooking to move the torque peak rpm up or down.

    If you want people to respect your point of view Nate, at least use #'s that make sense, or if they seem out of line, quote sources. :)

    --Andy

    MattP
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    03 Aug 2011 01:05 PM
    Don't forget that the EF CRX and Civic are on the same line in CSP currently. I suspect a weight conscious build starting with a 88 or 89 CRX HF would be able to get into the mid to high 1700's.

    I really don't like splitting lines that already exist unless there's a really good reason for it.

    Unofficial, etc, etc.

    MattP
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    03 Aug 2011 01:07 PM
    Andy Hollis wrote:
    solo-x wrote:







     The D16A6 motors were in the 140 range before cam gears were allowed. With cam gears they should be close (or over) 155whp with more mid-range torque.







     +15hp for a cam gear on an SOHC motor?  Seriously?  Where do you get this from?  The standard cam timing is about as optimal as it gets, unless you are simply lkooking to move the torque peak rpm up or down.

    If you want people to respect your point of view Nate, at least use #'s that make sense, or if they seem out of line, quote sources.  :)

    --Andy

     



    Andy, Nate forgot to mention the cam pulley is anodized red, clearly accounting for the additional hp... :P
    Tigermack
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    03 Aug 2011 01:37 PM
    Stop it now!
    JBrettHowell
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    03 Aug 2011 01:44 PM
    MattP wrote:
    Andy, Nate forgot to mention the cam pulley is anodized red, clearly accounting for the additional hp... :P

    Just don't try to run one with NOS stickers on your car or you'll blow your manifold.

    solo-x
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    03 Aug 2011 02:01 PM
    The info I got on the A6 motor was that without cam gears, ITB's were of little benefit. With cam gears, the ITB's picked up a good bit. So it isn't that the A6 motor gets 15whp from cam gears alone, but from a combination of mods working better with more tuning options available. Looking at that number again though, I agree, seems terribly optimistic. Probably as useful for this discussion as comparing stock power and weight numbers.

    So, the real numbers, or at least what I think they actually are. To make it easy, I'll go off a dyno sheet I have from an A6 motor with a hytech and all that and give it the same power gains I'm confident an SP Z6 motor would make over ST trim. For weights, I'll again go off what I know my EG made for weight compared to an attainable SP weight for the chassis and use the same weight savings on the EF Civic/CRX chassis using the ST weights I'm aware of for those cars.

    D16A6:
    Stock = 108hp
    ST = 115whp
    SP = 125whp

    D16Z6:
    Stock = 125hp
    ST = 125whp
    SP = 135whp

    EF weight:
    CRX = low 1750
    Civic = High 1790

    EG weight:
    92 CX = 1940

    Power to weight:
    EF = 14lbs/hp CRX - 14.32lbs/hp Civic
    EG = 14.37lbs/hp

    EF still ends up being physically smaller, lighter, and more powerful with no weaknesses to the EG. And that is assuming there are zero gains using a cam gear on the A6 motor.

    BTW, my Z6 motor dyno trace looked the same as other ST A6 motor dyno traces below 6k or so, save for that much larger spike in torque that the long tube intake gives the A6. The extra power of the Z6 is only on the top end.
    Andy Hollis
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    03 Aug 2011 04:36 PM
    MattP wrote:

    Don't forget that the EF CRX and Civic are on the same line in CSP currently.

    I really don't like splitting lines that already exist unless there's a really good reason for it.



    This right here is probably the biggest reason why this won't happen.

    --Andy

    Mugenlude
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    03 Aug 2011 04:47 PM
    mrhongkongwong wrote:
    JBrettHowell wrote:

    About 1900 lbs...and that is taking just about every allowance possible.

    IIRC, ST Civic's weight 1950-1980lbs, mine weighs 2070-2080. I'm not sure how much lighter the DX Trim would weigh but I could totally see both in the low 1900lbs range.

    Jeff- Andy's ST Civic was ~1965 lbs at Nationals the last year at HPD when we all went over the scales. He Had swiss-cheesed rotors (not legal now), a "custom" rear wing (not legal now), and likely the smallest driver seat (Andy is small). I'm sure that he has found some other items (anything you want to tell us about Andy), but I doubt it makes up for those items. So lets say the lightest Civic today is 1975 lbs. Most ST Civics are above 2000lbs, I would say most are around 2015-2025lbs.

    Andy Hollis
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    03 Aug 2011 04:59 PM
    Mugenlude wrote:

    mrhongkongwong wrote:

    JBrettHowell wrote:



    About 1900 lbs...and that is taking just about every allowance possible.

    IIRC, ST Civic's weight 1950-1980lbs, mine weighs 2070-2080. I'm not sure how much lighter the DX Trim would weigh but I could totally see both in the low 1900lbs range.

    Jeff- Andy's ST Civic was ~1965 lbs at Nationals the last year at HPD when we all went over the scales. He Had swiss-cheesed rotors (not legal now), a "custom" rear wing (not legal now), and likely the smallest driver seat (Andy is small). I'm sure that he has found some other items (anything you want to tell us about Andy), but I doubt it makes up for those items. So lets say the lightest Civic today is 1975 lbs. Most ST Civics are above 2000lbs, I would say most are around 2015-2025lbs.

    While your #'s are accurate, my Civic is no longer the lightest in ST. H. Dumpty 3 is. JHME build (Japan) nets the additional weight loss. Which is also the key to use of the 88 chassis as starting point for an SP build, as there are way more JHME hatches built in that year than in 89, which is when most of the assembly was switched over to Canada. Note that *all* CRXs are JHME.

    But yeah, I did find a couple more things. Nothing monumental, though. Real Life is in the way of any further development right now.

    --Andy

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