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Will a splitter on front and no Rear spoiler create problems


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#1 cyrus

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Posted 20 February 2016 - 02:56 PM

Will a splitter on front wand no rear spoiler create problems. I plan on a 1 to 2 degree rake on the 240z. Thanks.



#2 johnc

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Posted 20 February 2016 - 03:22 PM

Depends on how effective the splitter is. If it's effective enough to eliminated the 200 lbs of lift at 80 mph then you will have a car with aero oversteer at that speed.
----- John Coffey, Fabricator at Benton Performance, LLC

#3 RebekahsZ

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Posted 20 February 2016 - 08:56 PM

If the springs are stiff enough to transfer that downforce into the pavement.

1972 240z, purchased in 1991 for $900. Bone stock LS2/T56/DBW from 2006 GTO, swap completed in 2011. 400rwhp/435 rwtq. 2400# minus driver. JCI swap, Mantic ER2 clutch kit, JTR headers, single exhaust, Borla muffler, MGW shifter, M2 Differentials shortened Z31 CV axles, Z31 CLSD R200, Chequered Flag Racing billet stubs and companion flanges. MSD 2-step, Hurst roll control, both operated from switches on clutch pedal. 9" Hoosier drag slicks on Weld Draglites, 245/45/16 Hoosier A6/R6 on 16X8+10 Rota RBR. 225/250 sectioned coilovers, Koni 8610-1437RACE shocks, DP and EMI camber plates, MM shortened rear control arms, TTT front control arms, poly and aluminum bushings. Top speeds: Ohio Mile 174mph, C/GMS class record holder, best 1/8 mile 6.96 at 100mph, best 1/4-mile 11.0 at 126mph, best 60' 1.43, best 1/2-mile 148mph at GA 1/2-mile. Home Track-Jake's Dragway, Moulton, AL. SCCA autocross club - TVR, Huntsville, AL. Lets race!


#4 JMortensen

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Posted 24 February 2016 - 02:01 PM

I think the main thing you need to make a splitter work is a boxed in radiator duct, so that any air that gets into the front goes through the radiator.


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#5 johnc

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Posted 25 February 2016 - 08:52 AM

http://www.formula1-...t/splitter.html


----- John Coffey, Fabricator at Benton Performance, LLC

#6 RebekahsZ

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Posted 27 February 2016 - 05:08 AM

You don't create down force until you have exceeded the force of lift. Until you do that, you are only reducing lift to a value closer to zero. If you do achieve down force greater than lift on the front of the car and do not reduce lift on the rear, and have sufficiently stiff spring rates to translate these changes into the tires, you can actually change the attitude of the car as it goes down the track. So long as this change in attitude (I'm talking about aviation attitude, not mental attitude) doesn't cause your front to hit the ground, or your tail to hit the limit of rebound in your struts, or change your dynamic alignment settings, none of this really matters. We are talking extremes here, going pretty fast, and for me in a straight line, to get into these issues. Faster than most folks on this site will likely go. I'm not smart enough to add turning a corner into that complex discussion.

1972 240z, purchased in 1991 for $900. Bone stock LS2/T56/DBW from 2006 GTO, swap completed in 2011. 400rwhp/435 rwtq. 2400# minus driver. JCI swap, Mantic ER2 clutch kit, JTR headers, single exhaust, Borla muffler, MGW shifter, M2 Differentials shortened Z31 CV axles, Z31 CLSD R200, Chequered Flag Racing billet stubs and companion flanges. MSD 2-step, Hurst roll control, both operated from switches on clutch pedal. 9" Hoosier drag slicks on Weld Draglites, 245/45/16 Hoosier A6/R6 on 16X8+10 Rota RBR. 225/250 sectioned coilovers, Koni 8610-1437RACE shocks, DP and EMI camber plates, MM shortened rear control arms, TTT front control arms, poly and aluminum bushings. Top speeds: Ohio Mile 174mph, C/GMS class record holder, best 1/8 mile 6.96 at 100mph, best 1/4-mile 11.0 at 126mph, best 60' 1.43, best 1/2-mile 148mph at GA 1/2-mile. Home Track-Jake's Dragway, Moulton, AL. SCCA autocross club - TVR, Huntsville, AL. Lets race!


#7 texis30O

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Posted 01 March 2016 - 06:12 PM

I am going to go for the 200mph club in my 240...... I need all the aero help I can get.  I just bought wheels (15"x8") buying tires in the next couple days 275/50/15 to help........ a splitter and belly pan are essential in my eyes....


1970 240 Z #806, LS2 with a Maggie, t56, Fritz 8.8 swap, Coilovers, Cage, Flares, Wilwood.....

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'13 Tundra, CrewMax, .....I have issues...

"Driving this car on the street is like kissing a porn star on the cheek." -RebekahsZ


#8 RebekahsZ

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Posted 01 March 2016 - 08:51 PM

A lotta dirty power will overcome a little dirty aero.


1972 240z, purchased in 1991 for $900. Bone stock LS2/T56/DBW from 2006 GTO, swap completed in 2011. 400rwhp/435 rwtq. 2400# minus driver. JCI swap, Mantic ER2 clutch kit, JTR headers, single exhaust, Borla muffler, MGW shifter, M2 Differentials shortened Z31 CV axles, Z31 CLSD R200, Chequered Flag Racing billet stubs and companion flanges. MSD 2-step, Hurst roll control, both operated from switches on clutch pedal. 9" Hoosier drag slicks on Weld Draglites, 245/45/16 Hoosier A6/R6 on 16X8+10 Rota RBR. 225/250 sectioned coilovers, Koni 8610-1437RACE shocks, DP and EMI camber plates, MM shortened rear control arms, TTT front control arms, poly and aluminum bushings. Top speeds: Ohio Mile 174mph, C/GMS class record holder, best 1/8 mile 6.96 at 100mph, best 1/4-mile 11.0 at 126mph, best 60' 1.43, best 1/2-mile 148mph at GA 1/2-mile. Home Track-Jake's Dragway, Moulton, AL. SCCA autocross club - TVR, Huntsville, AL. Lets race!


#9 texis30O

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Posted 02 March 2016 - 07:49 AM

Well with over 600 on tap right now and more on the way I think I have a fighting chance....


1970 240 Z #806, LS2 with a Maggie, t56, Fritz 8.8 swap, Coilovers, Cage, Flares, Wilwood.....

IG: datlszguy

'13 Tundra, CrewMax, .....I have issues...

"Driving this car on the street is like kissing a porn star on the cheek." -RebekahsZ


#10 nismo silvia

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Posted 06 May 2016 - 12:03 PM

Sweet

 



#11 RebekahsZ

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Posted 10 May 2016 - 02:43 PM

texas300, when is your next try at the standing mile?  I plan to do the Arkansas Mile, and maybe a trip to Loring Maine (1.5-mile track) in 2017, assuming they can keep the facility.  I'm really curious to see where 600hp will take you.  Easy launch without tirespin, clean shifts right on the shift light, and nothing crazy or abrupt is the key.  Several of us have gotten pretty uncomfortable with drifting in the lane at around 170mph, so be careful.  A 1/2-mile experience can be really informative as well, as that lets you know how much mph you can hope to gain in the second half.  EasTNz and I plan to attend the Georgia 1/2-mile in Sept if it doesn't conflict with the Ohio Mile.  The 1/2-mile will just be an excuse for us to hang out together.  The Ohio Mile will be spring rate, alignment, chute and aero testing with the goal of going 175mph only.  But doing it safely.


1972 240z, purchased in 1991 for $900. Bone stock LS2/T56/DBW from 2006 GTO, swap completed in 2011. 400rwhp/435 rwtq. 2400# minus driver. JCI swap, Mantic ER2 clutch kit, JTR headers, single exhaust, Borla muffler, MGW shifter, M2 Differentials shortened Z31 CV axles, Z31 CLSD R200, Chequered Flag Racing billet stubs and companion flanges. MSD 2-step, Hurst roll control, both operated from switches on clutch pedal. 9" Hoosier drag slicks on Weld Draglites, 245/45/16 Hoosier A6/R6 on 16X8+10 Rota RBR. 225/250 sectioned coilovers, Koni 8610-1437RACE shocks, DP and EMI camber plates, MM shortened rear control arms, TTT front control arms, poly and aluminum bushings. Top speeds: Ohio Mile 174mph, C/GMS class record holder, best 1/8 mile 6.96 at 100mph, best 1/4-mile 11.0 at 126mph, best 60' 1.43, best 1/2-mile 148mph at GA 1/2-mile. Home Track-Jake's Dragway, Moulton, AL. SCCA autocross club - TVR, Huntsville, AL. Lets race!


#12 RebekahsZ

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Posted 03 October 2016 - 04:00 PM

Rear spoiler is now a permanent fixture on my car. With a splitter on the front, at 140 mph, the car gets twitchy. A tall rear spoiler settled that down. I made several 1-mile runs this weekend, all at or above 170 mph. With the rear spoiler, the car was very comfortable. My final "all or nothing/hell bent on victory" run was without a rear spoiler to try to reduce drag. I only went 170 again and the car was scary going down the track and slid to the left suddenly at least 10 feet upon throttle lift as I passed the timing beams. I actually had to cross-steer to keep the car feom spinning. I need to find an old post where someone told me to install a spoiler-I need to do some grovling and say:"You were right." I did try a BRE style short spoiler for one run where I ran a fluke 173, bit the car was almost as scary with that spoiler as it was with nothing. I would have liked to try that short spoiler again, and I will in the future, but my brother took it off the car while I was changing my pants-lol! I'm. Not going to draw a lot of conclusions based on a single run. My car is a 167-174mph car. This weekend it was virtually all 170s regardless of configuration. I did manage (1) 71 run with the big spoiler and the 173 with the small one, but I was still only 170 on the 2-3 runs I managed to have the courage to make with no spoiler at all. I always seem to have one unexplainable quick run during these meets that defies logic and makes me think the timing system had an error.

I know this post started about splitters. My car has acted this way consistently even after I cut the splitter off last year (I recently added it back on). We have a lift problem at the rear of these cars that deserves attention above 150.

Edited by RebekahsZ, 03 October 2016 - 04:08 PM.

1972 240z, purchased in 1991 for $900. Bone stock LS2/T56/DBW from 2006 GTO, swap completed in 2011. 400rwhp/435 rwtq. 2400# minus driver. JCI swap, Mantic ER2 clutch kit, JTR headers, single exhaust, Borla muffler, MGW shifter, M2 Differentials shortened Z31 CV axles, Z31 CLSD R200, Chequered Flag Racing billet stubs and companion flanges. MSD 2-step, Hurst roll control, both operated from switches on clutch pedal. 9" Hoosier drag slicks on Weld Draglites, 245/45/16 Hoosier A6/R6 on 16X8+10 Rota RBR. 225/250 sectioned coilovers, Koni 8610-1437RACE shocks, DP and EMI camber plates, MM shortened rear control arms, TTT front control arms, poly and aluminum bushings. Top speeds: Ohio Mile 174mph, C/GMS class record holder, best 1/8 mile 6.96 at 100mph, best 1/4-mile 11.0 at 126mph, best 60' 1.43, best 1/2-mile 148mph at GA 1/2-mile. Home Track-Jake's Dragway, Moulton, AL. SCCA autocross club - TVR, Huntsville, AL. Lets race!





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