Front end gets real flighty under WOT

I wasn't really sure were to ask the question but I guess it doesn't matter. I'm aiming this question at the remaining members here that have or had high horsepower 4th gen F-bodies.
Some may remember I did a complete top end overhaul, corrected valvetrain, springs, etc. on my Camaro. Along with a fresh opti, higher lb/hr injectors and higher capacity fuel pump. I brought my PCM to a local tuner(LT1 veteran)and had him go through the tune, injector constants, etc.
The car was fast when it was running shitty, now it's seriously fast. Backing up just a bit, when I did the true dual Hooker Blackheart exhaust, I also fixed a pinion seal leak and replaced a bent BMR torque arm with a frozen up heim joint that couldn't be adjusted.
Continued to next post, timer running out.

I reset the pinion angle and front torque arm mount. I also did the wheel and tire package that included a pair of 305 Mickeys out back.
After test driving the power increase was very noticable, with no top end breakup from lack of fuel capacity.
The car was driving real wonky for lack of a better description. I discovered they cause was that three out of the four brake calipers were sticking.
I replaced the calipers and rotors and use braided SS brake hoses. Problem corrected, car drives straight, doesn't pull to either side and brakes better.
Continued timer fixin to run out

After driving it and doing acceleration pulls, holeshot rips, etc. I've found that if I really rev it and side step the clutch I still blow the tires away all the way through first and second. Zero traction, BUT, if I rev it and feed the clutch in easy the Mickeys hook and it gets reasonable traction through the gears.
Continued

Now that I've presented all the facts, I'm aiming this question at all the high horse power F-body guys here.
When I'm running through the gears at WOT now, the car really lifts the front end any time my foot is all in it.
It drives really squirrelly any time I'm at WOT. When I get out of the throttle and the body sets back down, it drives perfect.
Continued

So, what do ya'll think is happening here? I'm I at a horsepower level thats constantly trying to lift the front tires under WOT? I "THINK" its making maybe 500-550 at the crank.
Does your high HP 4th gen act like this?
What do ya'll think is going on here?
Nolan

Quote:

---

Originally Posted by JOATMON

So, what do ya'll think is happening here? I'm I at a horsepower level thats constantly trying to lift the front tires under WOT? I "THINK" its making maybe 500-550 at the crank.
Does your high HP 4th gen act like this?
What do ya'll think is going on here?
Nolan

---

which mickeys at what pressure on the rear?? panhard is tight bushings tight on panhard?

Sent from my SM-S908U using Tapatalk

305/45r17 @ ~26-28psi on the street, hasn't been to the dragstrip yet.
I may need to check again, but the panhard bushings were good when I did the torque arm. I did tighten them up because I found they were a bit loose.
I remember because I put a Founders panhard relocation kit with the offset body brace to gain additional exhaust clearance.
Panhard bar was level and tight.

Quote:

---

Originally Posted by JOATMON

305/45r17 @ ~26-28psi on the street, hasn't been to the dragstrip yet.
I may need to check again, but the panhard bushings were good when I did the torque arm. I did tighten them up because I found they were a bit loose.
I remember because I put a Founders panhard relocation kit with the offset body brace to gain additional exhaust clearance.
Panhard bar was level and tight.

---

on osies procharged car the 275/40/17 always felt soft even with 26-28psi. it would spin like hell but always felt squishy

Sent from my SM-S908U using Tapatalk

Is the steering stable or darty on the Bird when you make a wide open pass?

Quote:

---

Originally Posted by JOATMON

Is the steering stable or darty on the Bird when you make a wide open pass?

---

mine is stable but im on skinnies and no front sway. osies gets a little darty with 275/40/17 fronts but his car is kind of stock alignment with a hair more negative camber and the max caster we could get, by eye/angle gauge . they both need to get an alignment lol

Sent from my SM-S908U using Tapatalk

Thanks for the feedback Shaun. I have never cared for the way the 275 fronts tracked on banked pavement. I have near new (less than 500 miles)Mickey Thompson street 275/40's on the front and they track worse that the old worn Sumo's that were on it.
You got me thinking maybe I need more negative camber to get the tires square with the pavement under WOT. The front end REALLY lifts under hard acceleration.
Hmmm
:hmm:

I think the "drag" style rear sway bar on the Formula helps keep the car stable. Without it, apply torque, right rear squats. left front comes up, and front end gets "loose".

Quote:

---

Originally Posted by Injuneer

I think the "drag" style rear sway bar on the Formula helps keep the car stable. Without it, apply torque, right rear squats. left front comes up, and front end gets "loose".

---

That could be part of it on the street, at the track it still flexes the rear bar enough to pull the front left higher than the right. valid point i didnt even think about.

Sent from my SM-S908U using Tapatalk

Have you tried adjusting the pre-load, using the adjustable end links? Should be able to keep it level. The bar is solid 1-5/16" chrome moly spring steel. The end links are bolted and welded to the subframe at the top. Steve Spohn had me sit in the driver's seat, and tweaked the adjustment. You're pushing a lot more torque than I was. I remember back in the day.... guy named "Joe O". Front tires 2-ft in the air with the front end at about 45-degrees..... insane.

Oddly, I was cleaning out old files from the basement last week and found the time slip from a single stage (~135 shot) pass. Lousy ET (11.162) due to weak launch on the high stall converter, but the 127.67 MPH was decent.

Quote:

---

Originally Posted by Injuneer

Have you tried adjusting the pre-load, using the adjustable end links? Should be able to keep it level. The bar is solid 1-5/16" chrome moly spring steel. The end links are bolted and welded to the subframe at the top. Steve Spohn had me sit in the driver's seat, and tweaked the adjustment. You're pushing a lot more torque than I was. I remember back in the day.... guy named "Joe O". Front tires 2-ft in the air with the front end at about 45-degrees..... insane.

Oddly, I was cleaning out old files from the basement last week and found the time slip from a single stage (~135 shot) pass. Lousy ET (11.162) due to weak launch on the high stall converter, but the 127.67 MPH was decent.

---

yeah i added a quarter turn but after was when i started having the issues with #7/maf backfires.

When i went the 9.90/9.93 passes there was a turbo ls fbody there with stock springs and a stock sway, back passenger side was on the ground on the hit (transbrake launch) and the front left was nearly 3ft in the air, was wild lol

Sent from my SM-S908U using Tapatalk

Quote:

---

Originally Posted by Injuneer

I think the "drag" style rear sway bar on the Formula helps keep the car stable. Without it, apply torque, right rear squats. left front comes up, and front end gets "loose".

---

Fred, What drag style sway bar did you use? Custom or off the shelf? You knocked a cobweb loose in my head because it made me remember a friend watching a holeshot commenting on how hard mine squats on the right rear and was lifting the left front tire. Maybe a "drag bag" in the right rear spring would be a cheap fix?

Mine will noticeably yank front up on rolling hits but other than going plaid, never feels squirrely. I have 275s on all four corners. 26in front, 28in rear.

I have a UMI drag bar, and if you actually like taking turns etc, would highly suggest not going drag bar route.

Spohn Performance.

https://www.spohn.net/shop/1993-1997...-Sway-Bar.html

Steve Spohn used my car for measurements. We met on one of the early F-Body bulletin boards. He had a full time job as a welder, was starting to make F-Body suspension and chassis parts as a sideline. He needed to borrow a T56 to do a mock up of a kit to install the T56 in a 3rd Gen. I had a spare, dropped it off in PA where he lived. After that I would help him with photos and measurements on my Formula. Pushed his products on the F-Body boards.

I bought his early design adjustable torque arm. Turned out to be a real dog…. tended to bend. He comped me an upgraded replacement, made a custom front chassis arm mount with DS loop, then upgraded it again with a beefed up custom design arm, with the DS loop moved back because of the Gear Vendors O/D. That's what’s on the car now.

I was supposed to be the “suspension guy” on Baxter’s 9.0-second LT1. When George dropped the LT1 and replaced it with a Gen 1 engine making 1,350 at the flywheel (383ci Dart Iron Eagle, Brodix spread port exhaust 14°? heads, huge Vortech centrifugal S/C) to compete in the PRO Edelbrock series Extreme Street class I just told him to drop it off with Steve Spohn. Steve had gone full time performance suspension parts manufacturer, in a huge, empty Alcoa aluminum factory in central PA. When Steve got done it was a consistent 1.20 (occasional 1.1x) 60-ft. Only thing we changed was adding front suspension limiters - George lived in fear of big wheelstands. Car pulled the front wheels no more than 6” to 8”, sitting dead level.

He ran three events running low 8’s at high 160 mph. But couldn’t compete with the nitrous car in hot weather. Swore he would run nitrous on his next build. A few weeks later he asked me to sell the car, and never built another one.

No such thing as “free advice”….. you have to pay the price of reading my BS ye olde tyme stories. :D

@JOATMON Are you looking for a street/twisty backroad setup or something more drag oriented? And what springs and shocks are on the front now? You can quell the front end lift by going with higher rate springs and shocks with more rebound up front, but you do sacrifice a little bit of load transfer to the rear tires by not lifting the nose. If it feels like the nose vaults up on the initial hit and then wallows around up there, I would focus on shocks more than springs.

I don't think camber is really going to net you a whole lot in this situation.

My has never really felt floaty with 275s up front, but I have been running streetcar springs (BMRs) for ages.

Quote:

---

Originally Posted by shownomercy

Mine will noticeably yank front up on rolling hits but other than going plaid, never feels squirrely. I have 275s on all four corners. 26in front, 28in rear.

I have a UMI drag bar, and if you actually like taking turns etc, would highly suggest not going drag bar route.

---

LMAO, I had to look up "going plaid", had no idea what it meant. Warp speed LOL
I do enjoy a bit of road course type driving, problem is, around here the roads are so shitty. Just when you feel comfortable taking some curves at speed , you hit some potholes and nearly lose control. Maybe a compromise between drag and road course suspension.
Nolan

Quote:

---

Originally Posted by Catmaigne

@JOATMON Are you looking for a street/twisty backroad setup or something more drag oriented? And what springs and shocks are on the front now? You can quell the front end lift by going with higher rate springs and shocks with more rebound up front, but you do sacrifice a little bit of load transfer to the rear tires by not lifting the nose. If it feels like the nose vaults up on the initial hit and then wallows around up there, I would focus on shocks more than springs.

I don't think camber is really going to net you a whole lot in this situation.

My has never really felt floaty with 275s up front, but I have been running streetcar springs (BMRs) for ages.

---

Like I mentioned to SNM I suppose I need a compromise between the two.
I'm trying to figure out why it drives so squirrelly under WOT yet drives and tracks pretty good when I don't have my foot in it.
Nolan

I'm sick right now, woke up Monday with the shingles in my left side. AGAIN, had it 9 years ago! So, I did some eyeball inspection without jacking it up or anything and found that the car is sitting 1/2" lower on the pass front versus the driver front. The rear is dead level.
After looking up with a flashlight, it appears the upper strut bearing seat rubber is collapsed, looks all squishy.
Now I'm beginning to think I may need to do a basic front end check and or repair job. Check everything for wear and replace if needed.
Once I get that done we may restart this conversation.
Nolan

"No such thing as “free advice”….. you have to pay the price of reading my BS ye olde tyme stories."
Fred, I for one, wish you would participate more in the BS conversations here. Your expertise is valued here perhaps more than you realize.
In today's world, "ye olde tyme stories" are a pleasure to read.
Nolan

Quote:

---

Originally Posted by Injuneer

Spohn Performance.

https://www.spohn.net/shop/1993-1997...-Sway-Bar.html

Steve Spohn used my car for measurements. We met on one of the early F-Body bulletin boards. He had a full time job as a welder, was starting to make F-Body suspension and chassis parts as a sideline. He needed to borrow a T56 to do a mock up of a kit to install the T56 in a 3rd Gen. I had a spare, dropped it off in PA where he lived. After that I would help him with photos and measurements on my Formula. Pushed his products on the F-Body boards.

I bought his early design adjustable torque arm. Turned out to be a real dog…. tended to bend. He comped me an upgraded replacement, made a custom front chassis arm mount with DS loop, then upgraded it again with a beefed up custom design arm, with the DS loop moved back because of the Gear Vendors O/D. That's what’s on the car now.

I was supposed to be the “suspension guy” on Baxter’s 9.0-second LT1. When George dropped the LT1 and replaced it with a Gen 1 engine making 1,350 at the flywheel (383ci Dart Iron Eagle, Brodix spread port exhaust 14°? heads, huge Vortech centrifugal S/C) to compete in the PRO Edelbrock series Extreme Street class I just told him to drop it off with Steve Spohn. Steve had gone full time performance suspension parts manufacturer, in a huge, empty Alcoa aluminum factory in central PA. When Steve got done it was a consistent 1.20 (occasional 1.1x) 60-ft. Only thing we changed was adding front suspension limiters - George lived in fear of big wheelstands. Car pulled the front wheels no more than 6” to 8”, sitting dead level.

He ran three events running low 8’s at high 160 mph. But couldn’t compete with the nitrous car in hot weather. Swore he would run nitrous on his next build. A few weeks later he asked me to sell the car, and never built another one.

No such thing as “free advice”….. you have to pay the price of reading my BS ye olde tyme stories. :D

---

we love your old time stories fred! keep em coming!

Quote:

---

Originally Posted by JOATMON

I'm sick right now, woke up Monday with the shingles in my left side. AGAIN, had it 9 years ago! So, I did some eyeball inspection without jacking it up or anything and found that the car is sitting 1/2" lower on the pass front versus the driver front. The rear is dead level.
After looking up with a flashlight, it appears the upper strut bearing seat rubber is collapsed, looks all squishy.
Now I'm beginning to think I may need to do a basic front end check and or repair job. Check everything for wear and replace if needed.
Once I get that done we may restart this conversation.
Nolan

---

that would be a good starting point as that could make it feel all wonky. feel better buddy

Oh, I forgot. Fred, I looked at that sway bar setup. It's a beast, looks like it would work good under the back of my motorhome. LOL
Thanks for the link to his products.
Nolan

Quote:

---

Originally Posted by JOATMON

Oh, I forgot. Fred, I looked at that sway bar setup. It's a beast, looks like it would work good under the back of my motorhome. LOL
Thanks for the link to his products.
Nolan

---

the stock style curved one is on the bird not the straight bar splined end one

Sent from my SM-S908U using Tapatalk

SHOO FLY