Trying to improve consistent 60 ft times with nose heavy 71 convertable

The car in the video below wieghs 4250 with me in it

https://www.youtube.com/watch?v=hURJ7cGE37w&feature=channel

I'm still chasing a decent 60 ft. time this one at Firebird in April was a 1.505 the best its done. In better air it ran 10.12 140 with 1.53 60 ft. I think I need a taller, softer front spring to get the weight transfered as I have to roll on the throttle to keep from spinning at the initial launch. As pictured it has 750# road race front springs and I'm going try some 260# Moroso Trick springs I had lying around if I can get them in the car.

We took some additional video at the Irwindale 1/8th mile last week and I could only manage a 1.60 as the track was a bit down on traction due to a lot of street tire cars. I get no front end rise unless the tires bite forst which I think is bascially backwards.

The rear suspension is Slide-a-links with Cal-Trac monoleafs and QA1 DA's. I get reasonable separation at launch but the side wall of the tire does not show any wrinkle (325/50/15 Hoosier Drag Radials). We took a little Flip video camera mounted under the car and could see the urethane bumper in the slide-a-link compres by about a half an inch so I have just made some solid bars to replace the sliding link to see if I harness some of that rotational energy to better plant the rear tire. But I think the problem is the fornt suspension not the back.

In front I'm running TCP strut rods and lower control arms which effective have rod ends instead of rubber bushings, and my own modified upper arms with poly urethane springs mounts which move with virtually no bind and Qa1 DA's also. I have seven inches of front travel measured at the spindle which according to Calvert should be enough, but the stiff springs I have had on it for the road course track day stuff have almost no stored energy for a drag strip launch so I don't get that kind of almost wheels up launch you see on a lot of early Mustangs. The front half of the car weighs 1170 D-side and 1080 P-side in the front with me in it. Yeah I'm fat too.

As mentioned I'll try the Moroso springs but I'm looking for a better recomendation or real world experience as I have not heard good things about them. Thanks in advance.

Havent run the moroso deals but have used six cylinder stock type springs on a falcon, stock control arms. Had to actually shim the top of the springs about an inch to get off the bumper's and that was with an iron head cleveland. worked well. You may not be able to go that light but certainly a lot less than the 750 you have now will help out.

dkp

I didnt hear it knocking the tires off in the video, what converter and rear gear?

CDMBill wrote:I get no front end rise unless the tires bite forst which I think is bascially backwards.

Actually it's the other way around........

You can't have nose lift and/or weight transfer without first having a given amount of initial traction.......no initial traction = no nose lift/front-to-rear weight transfer. If it was possible for weight transfer to happen first before traction happened (or inital rear suspension separation causing increased traction), then the nose would lift no matter how good/bad the starting line was.


A lighter front spring compressed more will definitely store/release more energy than a heavier spring. And that can be a good thing if that's really what the car needs. Only way to tell for sure is to try a lighter spring and see what happens. I will say that if you can find a lighter factory spring I would go that rout first (if possible) before buying a Moroso spring because they don't always work "perfectly" in every combo. Some times they act stiffer than the stock springs they replace, sometimes they take forever to settle & take a final ride height set.

You know a 1.5 60 ft is still pretty good considering that it's at 4200+ lbs.

Thanks guys. To Richter69 its a stock geared Lentech AOD 2.46/1.46/1.00 with a 9" Edge converter that stalls a bit over 4000 RPM.

Where I am trying to get to is a footbrake launch from 1500-1800 rpm where I can simply mash the gas instead of rolling down the throttle. The video is the best its done with a very fast roll down, but still a roll down not just mash the gas. When I do that it blows the tires off immediatly and I have to pedal it to get it moving.

Has anyone dealt with a particular business that really knows early mu Mustang/Torino front end setups for drag launches?

Does anyone know of a calculator for figuring installed spring height? I'd like to buy one more set of springs rather than trial and error a bunch of them as track time is precious around here.

I know the free and installed height of the exisitng 750# springs as well as another set of 620# which just rest on the upper bump stops about 1.5" lower static height. These are both the same wire size (.720) and free height (13") but the 750's have four active coils and the 620's have six yet they compress more. I have much to learn about coil springs.

Have you tried any different convertors? Sometimes something alot looser could help. Not sure if its an option if its a multi purpouse car???? Same thing with a programable ignition, to pull some timing and kill a little torque.

I had a much tighter 2800 stall 10" in the car which was intended for N20, which is on the car but not being used, as I'd like to solve for N/A traction and consistency first. It was the opposite situation, I could run 20 lbs. in the drag radials and it would just drive out with the throttle mashed and pick up when it got on the cam. 1.55 best 60 ft.

I did make a small cam change from a 112 to to 109 lobe sep with more agressive ramps (HT 440 and RT) along with the converter over the winter along with an increase in compression form 10.6:1 to 11:1 still on pump gas. The MPH went up from a best of 132 to a best of 140 so the changes did make more power at a slightly lower peak rpm no doubt due to the tightened lobe sep. Best ET went from 10.49 to 10.12, but I know I'm leaving ET on the table with the inability to leave at full throttle. All of the changes were intended to try and get the heap into the very high nines on motor through the full exhaust as driven to the track with the skinnies up front. My own stupid rules based on what we do at HRM's Drag Week.

Pulling timing is the last option but I think there is more in the chassis without another converter change.

I would try this question over at Yellowbullet on the stock suspension section. A guy on there named Moneymaker Racing seems to know his shit about older Fords.

Or call Calvert racing.

Fred Brown makes that variable stall control which is supposed to be good for 1000 rpm increase/decrease...you may want to try that?

Good ideas, I'm going to talk to Alex at Moneymaker re spring choice before I finalize that but I have found some good information by way of Jay Brown regarding spring calculators from the book, How To Make your Car Handle. The Moroso tech line said the car is too heavy for either of the two springs they stock that are the correct 5.5 diameter for a Mustang and suggested Landrum.

I've arrived at an OEM spring from a 73 Torino, Moog #8224 which is 17.81 free height, 10.5" installed and a rate of 357 lbs/in.

This should be an improvment over the Grab-a-track spring in it now which is 13" free height, 10.5 installed and 750 in/lbs. They are back ordered, of course.

You mentioned that you do some road course stuff. You wouldn't happen to be running a front sway bar, would you?

maverick wrote:You mentioned that you do some road course stuff. You wouldn't happen to be running a front sway bar, would you?

if you are take it off.

I've been running the car recently with the front anti-roll bar disconnected at both ends and secured with zip ties. I know it adds weight in the wrong place but I haven't removed it as I like to be able to switch back and forth quickly. I'd guess it weighs around 15 lbs.

I will be trying the new springs and roller spring perches next to see if I can get the weight transfer, hook and 60 ft. I'm looking for without removing it completly. If I need that extra .01 off it goes.

CDMBill wrote:Does anyone know of a calculator for figuring installed spring height? I'd like to buy one more set of springs rather than trial and error a bunch of them as track time is precious around here.

I know the free and installed height of the exisitng 750# springs as well as another set of 620# which just rest on the upper bump stops about 1.5" lower static height. These are both the same wire size (.720) and free height (13") but the 750's have four active coils and the 620's have six yet they compress more. I have much to learn about coil springs.

a coil spring is just a torsion bar wound in a cicle . more coils with same dia . just a longer bar . to figure install pressure free lenght minius instaled ht . times spring rate . same deal as a valve spring

Man I am in the same spot with my '71 Torino. Best so far is a 9.96 at 136 IIRC, a little over 4200 lbs.

The 60 foot times have plateaued in the mid 1.40's, with an occasional low 1.44 in there3 just to tease me.

The cal-tracs (even with monoleafs and rancho 9000's in my case) just don't seem to be able to work with a nose heavy car with a lot of power.

To help them out, I run smallblock springs, have increased front end travel, used empty shock bodies for max extension speed, and even tried a delay setup on my nitrous system.

Calvert is great to talk to, but he just is out of ideas with my setup.

The sad thing is that I had a home made leaf spring setup with clamps and el cheapo shocks back there that was capable of low 1.50's wth almost 300 less HP......

Good luck,

Greg

Greg, its great to hear from you. Your car has been one of my bogies performance wise as I have worked on my heap over the years. That and Cook's Galaxie and Travis Rice's car too. I've never met any of you guys but I feel like we are in some sort of club.

I'm installing a set of roller spring perches as we speak and I'm working thorugh a couple of different stock replacement springs to see if I can get to the sweet spot in terms of front end rise and weight transfer. I have read a bunch of threads here and other places and, with tires that fit in stock fender wells, I may have to consider pulling timing or a tighter converter to get to the next level absent just adding power (as if that's cheap or easy) which seems counter intuitive.

My biggest challenge remains getting enough track time and laps to be able to really test what I'm doing scientifically and make well thought out adjustments instead of a whole buch of changes in the hope that it'll work next time out. That'll be me this time again with new springs, an inch+ more front travel and some stored energy, not to mention solid links instead of the poly-urethane slide-a-link bars.

I'd just kill right now for that 9.96, but I do have a 140.26 mph. Oh well.

I may just have to spray it to get a 9 sec time slip.

As I look at your video, I notice that the front end doesn't rise as you come out of the water. Part of that is due to your stiff springs, but looser front shocks can really help. The loosest front shocks you can but are the Calvert Racing 90/10's, and they are not expensine(@$100/pair). They really helped our car's weight transfer and were more stable downtrack than the old loosie goosie pari that was on the car. It sounds like your are on the right track with the rest of the front suspension. We did change to Moroso trick front springs from stock 6cyl. springs, but wuold not recommend them for the street. I found out this year that these noseheavy high powered cars are finicky about how stiff of a sidewall they can handle. I struggled to find a consistent tuneup with my Hoosier 29.5x10.5 C11 stiffwall's with only a 1.51 60ft. avg. I went back to the smaller Hoosier 30x9 D07's with a somewhat softer sidewall and went straight to consistent 1.44 60fts. I also found that it helps to stiffen the rear shock a lot. I run the Rancho's on #9, the firmest setting. This allows the front to raise before the rear separates too much. Talk to John Calvert or his associate Mike, they will be able to set you in the right direction. If you do get it to hook, you might need wheelie bars, with all of the hp you have!

Hoosier 29.5x10.5's


Hoosier 30x9's

Thanks for the info Ken.

Update: The car is back together with the Moog #8314 springs with 1.75 coils cut, the roller spring perches from TommyZees (F15 Falcon) http://cgi.ebay.com/ebaymotors/ws/eBayISAPI.dll?ViewItem&item=260485218301
and my home made solid replacement bars for the Slide-a-link. The 8314 is stock replacement for a 72 Torino with a 429.

Both the front and rear ride height are lower with the front about an inch off the bump stop = 2" remaining upwards wheel travel. The rear is over an inch lower due to a much lower amount of pre-load on the bars, just 1/4 turn at the moment. The Slide-a-links required about a 1.5 turns to prevent a kind of axle tramp which seemed to be the polyurethane donut compressing and rebounding in moderately hard street driving, and occasionally at the track.

This is now a completely different car. With the front DA QA1 shocks set to dead soft for rebound (extension) and at the middle for compression I can roll into the throttle from a roll in first or second gear and nose comes up six inches, if I nail the gas the front end comes up harder and the car just goes instead of just spinning as it used to do. The differance in front end rise and appearant weight transfer is night and day. I'm going to try of few test launches at my nearby industrial park test facility but it won't get a real track test until the TnT at Infineon Sept. 15th.

I may stifen up the rebound and even reconnect the sway bar if the launch is too violent.

Ken, one other note, I bought a set of the Calvert 90/10 front shocks thinking that they may well be 'looser' than the QA1 double adjustables I have on the car now. With my old stiff springs the spring perch would move through a pretty severe change in angle from the bottom of the range of wheel travel to the top and I felt that the fixed set of mounting studs on the bottom flange would either bind up the suspension even more or break.

I've made a plate for the QA1's that allows me rotate the lower mount of the QA1's 180* so that the bottom mount can rotate freely on the bushing included in the QA1's lower flange style mount.
With the new taller springs that have 2 more active coils in them and roller spring perches the front end moves smoothly and a lot. I did a little test burnout and I get the front end rise now that looks like yours in the video coming our off the burnout. That was a great insight for me, thanks.

I know I have a bunch of shock tuning to do now but I think I have addressed the two core mechanical issues.

To Greg P. You might want to try the roller spring perches, I think they a major contributor to the speed and amount of front end lift I'm getting now. I thought the polyurethane perches were a cheaper equivilent but that is clearly wrong, at least on my car. Jay Brown suggested them to me and his 3800# Mach 1 works really well.

CDMBill wrote:Ken, one other note, I bought a set of the Calvert 90/10 front shocks thinking that they may well be 'looser' than the QA1 double adjustables I have on the car now. With my old stiff springs the spring perch would move through a pretty severe change in angle from the bottom of the range of wheel travel to the top and I felt that the fixed set of mounting studs on the bottom flange would either bind up the suspension even more or break.

I've made a plate for the QA1's that allows me rotate the lower mount of the QA1's 180* so that the bottom mount can rotate freely on the bushing included in the QA1's lower flange style mount.
With the new taller springs that have 2 more active coils in them and roller spring perches the front end moves smoothly and a lot. I did a little test burnout and I get the front end rise now that looks like yours in the video coming our off the burnout. That was a great insight for me, thanks.

I know I have a bunch of shock tuning to do now but I think I have addressed the two core mechanical issues.

Bill, its great to hear of your progress. I really like your idea on turning the spring perches. If you have a pic of your adapter I would be interested in seeing it. I always thought about the potential binding, but figured that Ford just made them that way to make assembly easier. I have been running Calvert shocks for 2 seasons now without breakng anything.

Within the last 2 hours I posted 2 new videos on that same Potobucket page, if it helps.

BTW what is your engine combo. It sounds really mean. 140mph @ 4200lbs.!!!

Ken, The combination is an IDT premier block at 4.532 bore and 4.5 stroke Scat forged crank, Scat 6.8 rods, JE 11:1 pistons. Heads are A460 2.30 intake as "rubbed on" by Charlie Evans, from Lem Evans with a port matched tall runner TFS A460 manifold. Comp 269/277 roller, with Crane Ultrapro lifters, Jesel 1.8 shaft rockers, Manton pushrods. Trans is a Lentech AOD with a 4000 stall Edge 9" converter, 3.89 9" and 325/50/15 Hoosier drag radials. Fuel and spark are managed by EMS-Pro Megasquirt EFI from EFI Source.

I have a picture of the plate and I'll dig it out and post.

CDMBill wrote:Ken, The combination is an IDT premier block at 4.532 bore and 4.5 stroke Scat forged crank, Scat 6.8 rods, JE 11:1 pistons. Heads are A460 2.30 intake as "rubbed on" by Charlie Evans, from Lem Evans with a port matched tall runner TFS A460 manifold. Comp 269/277 roller, with Crane Ultrapro lifters, Jesel 1.8 shaft rockers, Manton pushrods. Trans is a Lentech AOD with a 4000 stall Edge 9" converter, 3.89 9" and 325/50/15 Hoosier drag radials. Fuel and spark are managed by EMS-Pro Megasquirt EFI from EFI Source.

I have a picture of the plate and I'll dig it out and post.

I have an Evans Racing A-headed 562 that I figured would never fit with haeders on it. So we just use a little 466 with Charlie's TFS Street heads. With a set of headers, maybe I could run with those spray crazy 10.5 guys! Your combo sounds extremely cool, post pics of the car and engine if you could. The EFI should be great for the street! Just way cool!
Ken

Part of the reason I lowered the upper control arm pickup point 1.75" was to gain wheel travel and improve the camber curve for handling. The other reason was so I could shave the shock towers right at the port exits of the A460 heads so I could build a set of headers that weren't compromised by a too tight bend right at the flange. They are 2.125/2.25 step with a 4" collector and they aren't exactly equal length and they a little bit short, but they go back behind the suspension instead of having the two front tubes on each side wrap around like the Hookers do. And I can drop the tranny without removing the headers and they come out the bottom without having to remove any parts or jack up the engine so I'm pretty happy with them.

I know you could get that 562 in there and really spank em.