60 ft times for street 455?

[cray1801]

I know some of you are running the Comp T/A Drag Radials, I just got mine today :) . They are 275/60-15's on 10" x 15 rims. Other then the lower arms boxed (w/sway bar) and air shocks I'm stock. I'm running 3.42 posi and 3250 stall with a TH-350 trans in a `72 Skylark (~4000lbs.). I think I'm making 460 to 490 HP :Do No: at the crank. What kind of 60' times could I expect?

What's a good pressure for the street vs strip for these tires? I'm currently running 25 - 26 psi. on the street I can now floor it at 35 mph (in first) and it grips :) . I'm trying to avoid spinning as I'm sure the tread will disappear rapidly, maybe in small chunks?

The first "strip trip" (Thur.?) I may just drive around the water as I did with the standard T/A tires. I don't have a drive shaft loop yet.

With my previous 350 engine, 2600 TCI breakaway stall converter and hard T/A 255/60-15's the best I ever got was a 2.03 60'.

[buick535]

cray1801 said:I know some of you are running the Comp T/A Drag Radials, I just got mine today :) . They are 275/60-15's on 10" x 15 rims. Other then the lower arms boxed (w/sway bar) and air shocks I'm stock. I'm running 3.42 posi and 3250 stall with a TH-350 trans in a `72 Skylark (~4000lbs.). I think I'm making 460 to 490 HP :Do No: at the crank. What kind of 60' times could I expect?

What's a good pressure for the street vs strip for these tires? I'm currently running 25 - 26 psi. on the street I can now floor it at 35 mph (in first) and it grips :) . I'm trying to avoid spinning as I'm sure the tread will disappear rapidly, maybe in small chunks?

The first "strip trip" (Thur.?) I may just drive around the water as I did with the standard T/A tires. I don't have a drive shaft loop yet.

With my previous 350 engine, 2600 TCI breakaway stall converter and hard T/A 255/60-15's the best I ever got was a 2.03 60'.


I've seen info recommending the best pressure for drag racing to be 17 to 19 psi. They require a mild burnout.

Your air shocks need to go, they definately hurt launch capabilities of those cars. Air bags would work much better. Jim Burek P.A.E. ENTERPRISES

[gs1970455]

I run the Drag Radials and love em. 60' times depend on the track in my case. At Norwalk, very sticky, I got my best 60' times. 1.61. At our local track, less sticky, I run 1.7

I found that with a big burn out on the first run, little burn outs are all that's required for the rest of the day. I tend to run between 19-22 pounds of pressure at the track and sometimes, because someone forgets to bring the pressure back up for the street, I run the same on the street :)

275-60-15 on centerline convo-pro wheels. The drag radials work for me, but from what I've heard, they really vary from car to car.

The first set I bought lasted 2 years, the second set 1 year and my current set might make it a year.

Good luck at the track and let us know the results.

[cray1801]

buick535 said:Your air shocks need to go, they definately hurt launch capabilities of those cars. Air bags would work much better. Jim Burek P.A.E. ENTERPRISES

Jim, what if I seperate the air line (left and right) enabling independant adjustment of the rear shock pressure? I could pre-load the RR more than the LR.

Thanks for the inputs. Renee can you pull the left front tire?

[TWO72"s]

I would dump the air shocks and get some airbags and 50/50 shocks. You should be looking at 60' times around the 1.7 area. Rene could you PM me and let me know what size convo pros you are running and with what backspacing? Thanks, Chris

[OUTRAGEOUS]

I have air shocks on my 71, with Very mild 8.5 :1 engine with a good converter & 3.73 gears i had a best 60' of 1.70 on the drag radials mounted on stock wheels, with an et of 12.68. The 60' will avg. 1.70-1.75 depending on track & of course me the driver:Do No: I run the same pressure as what Jim Burek suggested. Randy

[gs1970455]

Renee can you pull the left front tire? No matter how hard I wish for it, they just don't lift. I guess my car would rather go out than up! :) Still would be nice to have a wheels off the ground pic of my car though.....its soooooooooooo close!

[buick535]

cray1801 said:Jim, what if I seperate the air line (left and right) enabling independant adjustment of the rear shock pressure? I could pre-load the RR more than the LR.

Thanks for the inputs. Renee can you pull the left front tire?




I'm not a suspension guru, but, air bags are a much better chioce in getting the car to hook. The air shocks I believe put different loads on the suspension and actually hurt traction to a degree. I have also seen air shocks cause pretty severe wheel hop situations. Jim Burek

[462 GILLEY]

I have been running 275-60 on stock Buick mags for 5 years now. I am on my second pair. Last year I started keeping records of all info. on the car per run. This includes everything from time of day & temp., to tire psi, spark plug checks ,gas, carb settings and timong. Plus alot more.

Last year I started around 18 lbs., and went down to 13 lbs.. Recording burnouts (short,med., long) and no burn out, most all of my 60 foot times are in the low 1.7, to high 1.6s.

72 Skylark, 455/350 3500 stall, 3.73 gears

12.50 at 107+ mph

Not bad for a daily driver weather permitting. But I am waiting to get my NEW motor together to see what it will do.

New Ericks cam, carb built by Catlin, and rebuilt converter. Hoping for 11:00s

Mike Gilbert

[cray1801]

Well the rain has delayed my first strip trip. :ball: Looking on the bright side.... Sat. the 21st is going to be sunny, low humidity and a high of 80! I'm planning on hitting the Fayetteville Motorsport facility to show and go! :) http://www.fayettevillemotorsportspark.com/_wsn/page4.html

A friend of mine gave me 5 gal. of VP gas, he said it was ~$7 a gal. Inputs?

Is there a good test to determine if your converter is slipping too much? I have a Torco that stalls at 3250 rpm, not the most expensive but it has a one year 100% warranty. I do not have a manual valve body in my trans.

[grant455gs]

I would think that loow 1.6's are very possible.. under the very best of conditions. What converter are you using? IMO, take the air shocks off and throw them as FAR as you can! :Dou: They suck for drag racing, and will hinder the launch.. in my personal experience. Get some 50/50, OR some cheap oil-filled, not gas, even stockers!!:Smarty: :bglasses:

I'm suprised they let you run without a driveshaft safety loop with the sticky tires. My track considers them the same as slicks.
Remember, safety stuff like this is in your best interest! I had to take out front seats and carpet to drill holes for bolts, and I used Grade 8 fasteners, especially the washers!!

[70 gsconvt]

You can get a driveshaft loop from Summit/Jegs that bolts right into the tranny mount bolts. NO DRILLING!!! It costs about $50 and installs in about 1/2 hour.

[grant455gs]

70 gsconvt said:You can get a driveshaft loop from Summit/Jegs that bolts right into the tranny mount bolts. NO DRILLING!!! It costs about $50 and installs in about 1/2 hour.

Not that I doubt you, but I've looked Summit/Jegs and only found the "universal" ones. Do you have a photo, or a link w/a photo??

[70 gsconvt]

Here you go:

http://gallery.bcentral.com/Gallery/ProductDetails.aspx?GID=4716958&PID=844223&page=1&sortOrder=0

They have several styles. Just hit the words "driveshaft loops" to get there whole list.

I have one and it went on easily and didn't have any installation problems.

[grant455gs]

Umm, that's not Summit/Jegs!! :jd:
but hey, thanks! those look really cool!:bglasses:

:beer

[cray1801]

70 gsconvt said:Here you go:

http://gallery.bcentral.com/Gallery/ProductDetails.aspx?GID=4716958&PID=844223&page=1&sortOrder=0

They have several styles. Just hit the words "driveshaft loops" to get there whole list.

I have one and it went on easily and didn't have any installation problems.

Would this work for a TH-350 trans.?

[grant455gs]

Yes, There is one there for T-350. Different part#.

[gswes]

Hey Guys,

Got a question about the drag radials - read somewhere that when you first install them, BFG recommends a big burnout, then let them sit for 24 hours. Once you go to the track do a decent burnout, then the rest of the day & night just clean them off. Have any of you experienced users heard this before? I just got a pair of 275/60/15 & want to make sure I "break" them in correctly.

Thanks, Wes

[70 gsconvt]

I know. I couldn't find it on their on-line catalog. The more I think about it, the more I believe I got it from T/A or Postons. You may have to call them to see who has it.

As for the DragRadials, that's how I broke my pair in.

At the track, do a good 7-10 second burnout THE FIRST TIME ONLY. John Force wannabees need not read this. After that, you just have to haze them a bit for a second or two to clean them off and race away. They chemicals in the tires that make them sticky stay active for several hours once heated up.

[TWO72"s]

I would use the drag radials for track only use. Mine are still loaded with small rocks, sand etc. Anything you drive over sticks to them only to be sandblasting your quarter panels as you drive. I really heated mine up one time in front of my house, just testing the linelock :laugh: So mabye I ruined them myself:af: I am running bf goodrich t/a"s on the street and will be getting slicks for the track:beer

[grant455gs]

TWO72"s said:I would use the drag radials for track only use. Mine are still loaded with small rocks, sand etc. Anything you drive over sticks to them only to be sandblasting your quarter panels as you drive. I really heated mine up one time in front of my house, just testing the linelock :laugh: So mabye I ruined them myself:af:

IMPE, small rocks and sand come out of the tires at 5,000 RPM'S!!
I don't think they're ruined at all, run them till their gone!! Small burnout at the beginning of the day, followed by 1-2 sec. burns..:Brow: They're FINE!!:beer

[cray1801]

Well guys, if wasn't meant to be (at least this Saturday). I had a flat on the way to the strip, one of the Drag Radials separated at he bead :mad: . I can see the group of steel rods around the bead when I pull the section back. Luckily I was only 3 miles from the house, I pulled over immediately but there was very little warning. Didn't hurt the rim too bad :Do No:, nothing a file couldn't smooth out.

Looks like the street tires go back on tomorrow (spare is on for now), but weather permitting I'll be at the Test & Tune Thurs. I guess high 12's is my goal for now... I need to get an extra set of rims and new Drag Radials.

[grant455gs]

Hey Craig, dammit!:Dou: I was really lookin forward to hearing your track times! :stmad: :stmad: Any thoughts on WHY this happened?? Maybe DAMAGED during mounting?:af:

Why do you want to run drag radials so bad at the track? Why not just get some slicks for track use? IMO MUCH MORE RELYABLE/REPEATABLE AT THE TRACK. Unless you're competing in a class that requires them...why compromise traction?

Just curious,

Jeff

[70 gsconvt]

That would be my advice too. As long as you're getting separate rims anyway, GET THE SLICKS. They'll be .2 quicker than drag radials.

[GS Kubisch]

Hoosier Quick Time Pro's or MT ET Streets will hook just as well as slicks in this application and you can change them at home the night before going to the track.
Personally I ran my ET streets all the time,on the track or the street,back when my car went low 12's.

PS
Don't tell Renee......
But I really think Drag Radials are pathetic on a big block car.
Unless you're racing a class that requres them,I would stay away from them

[cray1801]

Good input guys, and I will have some numbers soon! :Brow:

A friend of mine had these BFG Drag Radials, he had used them on his Charger, I got these at a major discount (I thought). I was planning on running them on the street for a while, at least until I got an extra set of rims. Anyway he said "if they don't work out I will make it right". My street tires are 80% done so I thought what the heck. The problem was he had previously used screws on the inside and the tire turned ~some anyway, probably what caused the problem. I thought it was o.k. as I've been driving on them for several days.

Tomorrow I'll be purchasing a set of standard T/A 275/60-15's for these rims.

I'd like to have another pair of these rims for some street legal soft tires and I could do as Gary did. These rims are 15" x 10" wide with 4.5" back spacing. It says "CRAGAR IND. RACING WHEEL DIV." on the outside of the rim and I think they were purchased about 3-4 years ago, anybody know how I might aquire a pair?

Man this thing look misleading on the right rear (with the 215/75-14" spare) corner as shown in the avatar.

[cray1801]

Check it out :laugh:

[GS Kubisch]

Craig
Those wheels were discontinued by CRAGAR......(I think they're called ''superstar pro stock"?)

Try
http://aolsearch.aol.com/aol/redir?src=websearch&requestId=fa7334f2f1717126&clickedItemRank=3&userQuery=harlow+tire&clickedItemURN=http%3A%2F%2Fwww.harlowracing.com%2 F
or something like that,they had some on closeout last time I was one their site

[cray1801]

THANKS Gary! I think I found them the "RS Super Star". They are $180 each in the 15 x 10 size.

[70 gsconvt]

I'm running 15x10's with 5-5/8" backspacing under my car with 325/50R15 DragRadials. I did have to trim the top of the wheel well back about 1/4" or so for proper clearance. NO other mods. People have asked if I have mini tubs in the car.

I also had to install air bags to take the bounce out of the car when I would hit a big dip in the road or bump as they used to rub up in the fenderwell. No problems with the air bags at 15 psi or so.

[Ken Warner]

Anyone out there running the Nitto 555R drag radials... Looks like they finnaly started making them in a 275-60-15. Have heard they were way popular with the rice/mustang crowd... Anyone with first hand experience care to speak up???


regards

[Nitro71455]

I'm running Nitto 555r's and like them a lot.

They hook about the same as the BFG's Drags, but you get almost twice the life out of the tire.

I'll by them again.

[cray1801]

Good info. While it would be nice to run slicks, I'd prefer something legal that I could drive to the track on those racing days. Now I just need to save a few $'s for an extra set of rear rims.

Rich, what kind of pressure do you run? I've heard 27 psi. for the street to avoid using them up during normal (I mean slow) driving. Have any data on how they hook compared to what you previously used?

[Nitro71455]

cray1801 said:

Rich, what kind of pressure do you run? I've heard 27 psi. for the street to avoid using them up during normal (I mean slow) driving. Have any data on how they hook compared to what you previously used?

I don't run any lower than 23 psi at the track, and run about 36 on the street. Keep in mind tho, I'm running 17's and don't have a lot of tire on the rim. Man I wish they would make a 295-50-17. That would be awsome.

The best 60 foot time to date is 1.85. I've added some No hops and adjustable uppers for this year, so hopefully that will get me in the 1.7's (with not much side wall). The Pair of BFG's I used neted me about .1 better, but we were also dealing with 15 inch rims with a bit more sidewall flex/give. Personally, I think they are about the same when it comes to hooking. There also hard to beat on the street. You do want to have Clear Bra or something put on your quarters (that's what I'm going to do) the tires like to pick every little thing up and chuck them.

Everyone I've talked to running Nitto's Drags has been happy with them. I think there the best Drag tire out there as far as everyday driving tire ware goes.

[TWO72"s]

Craig, I thought 15 + 10 rims had to have a larger backspace like Phill has. How did yours fit with 4.5, did you have to trim the chrome lip on the quaters?

[GS Kubisch]

smaller tire....

[70 gsconvt]

Like Gary said, my tire is 2.5" wider than his.

[cray1801]

Yeah, Nitto's sound good.

No trimming necessary, but It's about as big as you can go with the 4.5" backspacing. A wider tire with this rim would require some trimming.

[TWO72"s]

Allright guys, I am looking at weld draglight rims 15+10 with 5.5 back spacing.I would like to run MT et steets 28+10.5. Will they fit on a 72 GS without any trimming? I am dying to get these, just dont want to get the wrong size :beer Thanks

[GS Kubisch]

Yes..that will be perfect.
Should look pretty friggin' tough/serious too:beer

[Jeff Kitchen]

For what it's worth, my 72 has 15x10 Draglite's with 5.5" backspacing and 29.5 x 10.5 Phoenix slicks. I had to trim almost all of the lip off the top of the wheel opening, then I rolled the chrome trim up to make a smooth "rolled" edge. I have about 1/4" clearance on the outside and 1/2" on the inside of the tire. It rubs a little going around corners, but I don't race around corners. Have fun.

[87GN_70GS]

Craig,

What are the specs on your Earick cam?

[cray1801]

I'm running the TA-413 cam; 234/244 int./exh duration at .050 and .500 lift. Right now it is installed at 107 intake centerline and I'm using the factory 1.54 rockers.

[69GS400s]

FWIW....I do some lurking at the TurboBuick board and they love the nitto's over the BFG drag radials

personally - I have the 275-50's and i dont think I've ever actually hooked 100% and most of the time its alot less than that I either have to leave soft or pedal it slightly and i've tried Big burnout, small burnout, and varying pressures until i was skating and scared myself crossing the 1/4 line (think that was down around 13# or so.....)

[grant455gs]

personally - I have the 275-50's and i dont think I've ever actually hooked 100% and most of the time its alot less than that I either have to leave soft or pedal it slightly and i've tried Big burnout, small burnout, and varying pressures until i was skating and scared myself crossing the 1/4 line (think that was down around 13# or so.....)

For what its worth, don't be so quick to "blame" any sticky tire. Instead look to suspension improvements. Don't "let" tires stick, MAKE THEM!!:stmad: :Brow:

There are some very fast wheels UP 8 second cars using BFG Drag radials (and the like), FWIW.....:Do No:

[cray1801]

Well since it's the hottest day of the year so far ~96 degrees I think I'll go to the 1/4 mile drag strip. Anyone coming to Fayetteville Motor Sports Park for test and tune tonight?

Tune in tomorrow for the scoop.

[69GS400s]

Good luck Craig......

[Nitro71455]

cray1801 said:Well since it's the hottest day of the year so far ~96 degrees I think I'll go to the 1/4 mile drag strip. Anyone coming to Fayetteville Motor Sports Park for test and tune tonight?

Tune in tomorrow for the scoop.

I'll be waiting......

After all you have been through, I sure hope it holds up to your expectations :TU:

[Da Torquester.]

For some of you guys running full weight Skylarks with Hoosier Qtps, what psi. do you race at? I'm currently running about 15 psi. Anyone run different pressures?
John :)

[cray1801]

Had a good (not great) day at the track :) . Not the best day considering how muggy and hot it was but hay everyone was a little off on their times. My plan was to shift at @ 5200 rpms for the first several runs while I did some tuning. After the tuning stage, I planned to rev it to ~5800 rpms to see what she could really do.

First run, spin through first gear, shift at 5200 rpms. The result was a 13.28 at 104.8 mph. I was racing a modded Maxima that ran a 14.69 at 93.9 mph, margin of victory 1.6 sec.

Second run, highlight of the night, against a new Z06. We came out about even but just off the line I pulled 1/2 a car length in first. This took a lot of mental control not to floor it in first gear and loose traction :eek2: ! I shifted at 5200 as planned, I lost some ground initially but pulled on him good through the mid 2nd gear rpm's. As I shifted into 3rd he started to pull on me some but I was too far ahead. The result was a 13.20 at 105.3 mph to a 13.28 at 106.2.

Before the third run I changed the secondary rods of my Q-jet from 0.040" to 0.030"

This was the most entertaining run (for the spectators). Again planning to shift at 5200 rpm, I started to spin about 60' out but I stayed in it thinking it would hook. Went into second and continued to spin at ~5500 rpms. Had to get out of it at ~70 mph because I was crossing up bad just past the 1/8th mile mark. Got back into it after I straightened up and ran a 14.14 at 101.7 mph. From this run I figured I was making a little more power and made no changes after the run.

Forth and final run :( . I decided to turn it up and shift at 5800 rpm's. I hooked fairly well; it pulled hard through 1st and 2nd. As I was getting ready to shift into 3rd I hear a sputter and a tapping sound from the right bank. I let off the gas and was on the brake a ways before the finish line. Thinking the worst I sadly cost cruise to the ticket booth. This was the worst return road drive ever! Picked up my slip and gently proceeded to the pit and shut her off. My friends came over with smiles on their faces thinking this was the best run, they just thought I got out of it early. I'm almost sure the problem is valve train related, maybe pushrod adjustment nuts loosened? I talked with two experienced racers, independently they both said about the same thing. Should be minor but I decided to leave the car there to be safe. Anyway, for the record I ran a 13.36 at 94.1 mph. Going to pick it up with a trailer tomorrow morning.

60' times were only fair with the street radials, they were in the 2.15 to 2.20 range.

Any ideas? It occurred at higher rpm's. The preload was set at .040" with the adjustable pushrods. I know roller rockers would be a better set-up and give me a much better ratio (1.6 vs. 1.54) but man $600?

I also noticed as speeds approached 90 or so the car seemed to gently sway back and forth. The first time this happened was on the street a couple of days before. It occured on each run at the strip, guess it could be the 275/60-15 TA radials or the air shocks? Tire pressures in the rear were 26 (RL) to 28 (RR) psi. and 36 (FL) and 33 (FR) to help jack weight around some. I've always done this with success. There was a noticable crosswind as well.

Here's a early evening picture before things got crowded.

[69GS400s]

Man.....how could you leave without even ripping the valve cover off ??? I never would have slpet the night just wondering.

Your MPH is up there but those 60' times gotta go....DOWN !!

where you on drag radials ?? I dont think I ever tried more than 20# at the strip with mine. I would alomst guarantee you better 60' with lower pressure

You need to find yourself a patch of concrete in the middle of no-where'sville....bring a push broom (to clear off a launch pad) and a couple gallon jugs of water and practice your launch. Im far from being Mr. Dragracer but I'll tell you this - from practicing I know my car pretty well and how to launch it with minimal tirespin.

Here's hoping you didnt hurt anything......

[cray1801]

Standard TA radials and a slick track. My previous best 60' time with the 350 engine was 2.03 sec

[grant455gs]

I hope everythings all right. Let us know whats up.

BTW, how could you sleep? I couldn't even leave my car at the track when I windowed a block. I think I would have at least taken valve covers off, pulled spark plugs, checked oil/water, ect.:Do No: :Dou:

Are the air shocks still on?

Buy some slicks:Dou:

[cray1801]

Got the car home today. I peeked under the valve cover before we loaded it on the trailor :) . The end of the rocker shaft broke (passenger side) right at the front bolt hole. The end was still attached, the crack came from the bottom up as expected, I'm sure glad it did not come off.

I have not measured the rocker shaft thicknesses but I know I have one that is new looking (driver side) and one that is older (passenger side). Should I just get a new shaft or a remanufactured set with maybe a better ratio than my 1.54? What material or treatment should I look for in a new (stronger) rocker shaft?

[Da Torquester.]

Get a new shaft or shafts. Rick Henderson had some shafts of which had grooves worn in them from under the rocker arms. Sounds like he caught his just in time. When you change your shafts, look for this wear. I'm a little concerned about mine now. :confused: Do you know how old your shafts are?
John :confused:

[70 gsconvt]

You'll have to spend $325 at TA to get just replacement rockers since you no longer have a "core" set to give back.

If it were me, and I'm crazy, I'd go the extra $300 and get the 1.6 roller rockers. They'll never give you any more trouble up top. And they look great. You'll get a little more HP with the better ratio. It's a win/win situation. The wife can't even argue about it. It's either $625 or the car sits and gathers dust.

Wait, don't tell her that, she may prefer that. Or worse, just sell it!

I have to agree that you must do something about your tires. If you're going to run drag radials, keep the pressure between 15-20 lbs for best traction. Or go for the slicks and really hook up. I went from 1.92 to 1.75 going from drag radials to slicks. They do work great.

[Ken Warner]

About 1.5 years ago I had a thread going about this kind of stuff... If I remember right the original 70 vintage rocker shaft on my car had a wall thickness of about .170 inches... The Melling brand replacements along with the Poston "heavy duty" shaft was a whopping .150 inches thicks...

Well the original shafts were 30 years old when the aluminum rockers and simply wore them out... Over the next 6 months 2 of the Melling replacement shafts bought the farm.

Wouldn't have been a big deal either time but the second shaft that let loose was about 200 miles from home. I did however discover how well the car will run on 7 cylinders for 200 miles!:jd: Both shafts broke at the ends on the driver side.

SOOOooo.. to make the long story longer I call up TA. They don't really list their shafts as heavy duty but if you talk to Dave or Mike they will tell you that they certainly are... Well with the mellings in the trash and the Postons on their way back to Alabama (just a repackaged Melling) it's either $100 (I think) for a pair of these shafts or ante up the $500+ for the rollers.

The TA replacement shafts are .220 inches thick!

ROCK AND ROLL BABY!!!

Year and a half later they are still going strong. I also divied up the $10-$20 for the studs and nuts for the rocker shafts as they were highly recommended.

In conclusion:Smarty: you're choice if you want to spend the bucks or not but it doesn't take a rocket scientest to tell the differences in strength between those wall thicknesses.


regards

[cray1801]

Well, I finally got back to working on the car replacing the rocker shaft, check out the crack! Hay, I'm glad it didn't break off.

If this happens to you make sure the pedistal is on the head is not damaged. Luckily? I used shims under the shafts to get the proper geometry so I just had to replace the shim as it is damaged and no longer even/smooth.