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When I built my motor 8 years ago before the cobra was every thought of I figured 500 hp and torque plus was plenty for one of these cars. I see now people putting in 700 plus monsters. Mine is somewhere around 525 in each category big block ford and I spin in every gear and before I know it I’m almost at 100. I have never had it floored most maybe 70% throttle as the get up is insane as well as wheel spin. Curious what everyone is doing with that much horse for the street can’t seem to use it in these cars. Also do yours pull hard I think because of my wheel spin may be the issue mine doesn’t seem like it does. My friends tricked out Audi s4 pulls harder. Currently I have 3.73 in the rear. 4 link, nitto on the rear. Curious to see what you are all doing for a little more bite.
 

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I'm in a similar power/tq range, and my car really makes its bank between 4000-6000 rpm with a mostly open throttle. It's actually fairly mild just driving around the town, though it will spin first through third if you want it to (and occasionally when you don't mean to). It sounds obvious, but I've found that if I want my car to really pull, I've got to get that throttle opened up well beyond where it is when I'm normally driving around. Until you're used to driving it that hard, it seems like you're ending the world with your exhaust note.
 

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My original car had similar HP/TQE numbers, 525-535 range for both. TKO-600 .64 OD, 3.73 gears. 315/35-17s. Had a mechanical throttle linkage that was adjusted for a lot of pedal throw which gave a lot of room for modulation, I believe that this enhances control.

First gear with the 3.73s was too short, I was shifting way too soon in first. Based on a few friends switching to alternate rear gears I followed suit and changed to 3.27s. This really helped and it still ran 11.8/120 on my first trip to a drag strip. I could also run 4th way past 140 so shifting to 5th on a road track wasn't necessary. It would cruise at 2,200 rpm @ 80mph.

Once I was moving the power could be used but it would still light 'em up in first at 2,500 with a solid push on the skinny pedal. I also think that a progressive push rather than an all-in-one stomp helps to maintain grip.

There are many gearing calculators, you may want to play with the numbers.

Jim
 

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I have the mechanical linkage as well and that probably adds to the feel of control I have during normal driving. It has a lot of throw, so I really have to want it to go fast for it to go fast.
 

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Do some searching on tuning the 4 link. Not sure they are all the same but some FFRs have multiple holes in the frame mounts or the adapter under the axle that the LCA bolts to. Sometimes using a different hole will change off the line traction but I haven't messed w/ a 4 link so research that. Also look into alternate springs and shocks. Other than that, I'd guess drag radials are in your future. I think it is nitto who says one of their regular tires was developed to work well w/ rear drag radials.
 

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The photo shows my car when it had the 4 link rear and pro shocks. It would pull consistent 1.70 60 ft times at the strip on the Bridgestone RE73 tires shown on the car. The trick is to get weight transferred to the rear to plant the tires. If you stab the throttle it's easy to break the tires loose. Rolling into the throttle smoothly but quickly to shift the weight should allow you to hook up much better. A good progressive throttle pedal and smooth clutch obviously help.

FFR2100-hr.jpg
 

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Right off the bat, plain and simple, you have the wrong gear ratio for the engine. Those gears would be best with 225 hp, you should change to a 3:27, or even 3:08 and you would have a much better street car.
 

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Sean
 

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What exact tires are you running? Nitto 555? If so, there is your problem. NT05 or NT01 is what you should be looking at for 500HP.

What transmission? Rear end ratio is only one part of the equation. I agree that 3.73 is too low for a high HP car with any of the common transmissions that we run.

I see a lot of guys set their cars up with the rear higher than the front. You want to be even or a little bit of squat. You may have to adjust pinion angle if you lower the rear. I dropped my rear 1/4" and really noticed the difference during autocross.

I have 500+HP a 3 link, 3.31 rear, TKO600 road race, and run NT05s. I can't just romp on it. But I can use it all if I use the throttle correctly. Autocross is a great, and safe, place to learn throttle control and other skills needed for these cars.
 

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I would change to 3.08s and it will be a totally different animal. I can get 600hp/500tq down no problem but I have DOT slicks
 

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Posted wrong thread

Sent from my iPhone using Tapatalk Pro
 

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Here's an OLD video of my MK1. It's nothing special in the vid but the 500HP car HOOKED from the dead. It had 373 gears, 4 Link geometry pinion & instant center set up/tuned by a chassis shop , MT DR's set at 20psi, Spec II Clutch, Tremec 600 w/2.97 1st gear, 351W with Brodix Heads, decent roller cam, made [email protected] 400 tq. When I sprayed 100 shot on the street in 3rd/4th if needed it made 520rwhp on dynonometer. I did the Nos on a window switch...On at 3800rpm....off at 6200rpm. It was on the nitrous shortly before passing the camera.
Never had a problem hooking 1st. Always went straight. The video is from dead stop roll out with a short stab to shock the MT's..maybe 1/2-2/3 throttle , pulled 2nd as it passed 5000rpm w/o lifting then stab the gas to floor. After the rear was tuned the MT's stuck at red lights and anywhere on a 2nd gear roll....especially on concrete. Pullling the button for the extra 100 was always fun in 3rd. Once racing my buddy's Viper I rolled at 15-20mph and stabbed it in 2nd with the nitrous ON....the car dead hooked, lifted a bit, got just a bit wiggly but kept it straight .... and it was GONE.
If I could suggest, get your 4 Link UCA/LCA's set up properly for instant center straight line hook and no hop. Soften your DR psi. Nitto 555R's are awesome. They stick real good, ride better, more weather resilient, last longer.... but Mickeys stick way harder. I swapeed mine out every 3rd season...worth it if your playing. On the Nitto's try a bunch of 3 foot long burnouts at 30-25-22-20 psi until your see the full tire on the street...flat black is best:)->). That's your best psi for hooking. Mine went flat black at 18psi but handled better at 20psi. If you have the longer 2.97 1st gear you can make the 3.73's work . If your 1st gear is 3.27 then 3.55's. Anyway......you can hook 500HP with a little gear :)->) .
 

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From above, "4 Link UCA/LCA's set up properly for instant center straight line hook and no hop." Generally, raising the instant center will cause more weight xfer. Shocks need adjusting to control the rate of xfer. The next problem you will see on a road course is when you cross the apex of a fast sweeper and roll into the throttle, the front lifts and washes out. You can't be a sports car and drag car w/o changing things. The autox guys have another set of issues. I had a 530 HP 4 link. I had two holes for the front LCA, a low hole for track and a high hole for drags. Clutch style posi is OK for drag racing. Get a Torsen for the track. Ran 11 teens @ 131 with a 2.75 gear and an automatic. I would have been in the 10s with a gear. Stab the throttle and its a smoke show. Standing start and roll into the throttle and the Mickeys don't slip at all. The rear would do a little dance at 40 mph when the converter locked. Shift to second at 70 mph and you have a couple of car lengths on the guy that spun the tires shifting into second. Some will say that automatics waste HP. That's OK, we have extra.
 

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[QUOTEraising the instant center will cause more weight xfer. Shocks need adjusting to control the rate of xfer. The next problem you will see on a road course is when you cross the apex of a fast sweeper and roll into the throttle, the front lifts and washes out. You can't be a sports car and drag car w/o changing things. ][/QUOTE]
YUP.....straight line chassis tuning is not favorable geometry for autocross. But, there are ways to dramatically improve safety & straight line street performance with 500HP.
 

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For "lite to lite, 1/8th mi or 1/4mi " do what Mike,Jam,Tom said. Works for me--just saying. My old MKI ('Ol #1437) isn't setup for road courses, auto-cross ect, but pretty damn quick otherwise and fun to drive (180,000+mi.!)lol
 

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Part of the fun of my warmed over 302 (maaaaaaybe 300 at the crank) with somewhere over 100K is that I can give it Hell and not die in a fiery wreck...at least not yet. :)
 

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Levy 5 Link and Nitto NT05's 500/500 408w that dyno'd rock solid up to 7k before being shut off. I have only had it legal on the road for a couple days but have hit it hard a couple times from a roll and so far it squats and goes like a rocket. I haven't hit hard from a stand still yet though, I am sure it will burn up the rears pretty easy.
 
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