[DonnyD]

Hello guys. Been a while since my last post. Finally got my dyno sheet back and made 577hp/618tq. This was with ram air manifolds, rather than the Doug’s long tubes that are going on my engine.
Car is a 69 GTO, full interior, a/c street car.. 455/474 engine. Decided to go with a tkx tranny paired up with a moser 9” 3.50 gear. Planning on utilizing MT drag radials for daily driving and just want a budget friendly suspension that will hook good and not be too uncomfortable. I thought of doing a BMR stage 2 kit with all the fancy knickknacks but it’s kind of out the budget at this point. I know the factory 4 link isn’t the greatest. Would you guys leave it for now, save for a BMR kit, UMI kit or are there any coil over kits, spring modifications or adjustable shock setups that have been successful for some 90% street/10% strip applications that helped you cut lights quick? Thanks for the help.

[chiphead]

Stock suspension with boxed lowers, adjustable uppers, 4-speed braces, the proper stock or wagon springs and good shocks will work wonders. The stock 4 link suspension can 60 foot into the 1.4s, good enough for low 11s, which is under the rollbar rule.

Good shocks is where you spend the money. If the car wants to twist on launch, you may need one of the fancy rear swaybars. But if the car is 90% street, don't ruin the street manners doing the typical drag spring/CE shock dance. I just converted my '67 away from that, no fun rubbing tires on the fenders and wallowing around on the street.

[XLR8STEVE]

Chiphead is right on the money. My first build was similar to that on my 70 with a TKO600 & similar HP numbers and I was consistent 11.70s. I do recommend the BMR extreme anti roll bar. Mounts to the axle tubes and ties to the rear crossmember on the frame. Helped a ton getting both tires to hook evenly. Hope your pinion and tranny yokes are billet.

[JLMounce]

If you can't box the lowers yourself, or have them done, I'd definitely add an aftermarket lower along with the uppers at minimum. You're shoving a lot of power through the rear-end of a heavy car at nearly 2x the power that it was designed to handle.

The fact that you're going to have a drag radial on this that will provide a good amount of traction, I'd probably have every brace back there you can get. I'd recommend the Global West pieces myself, but BMR also makes some good stuff.

If you can't afford this stuff right now, I wouldn't put a drag radial on it until you can afford the parts. If you get to playing around with the car and good traction without doing anything to the factory pieces, you may find that you're buying the aftermarket stuff a lot sooner than you plan on. You could be fine, but you're definitely playing a game of Russian Roulette.

[Scarebird]

I would honestly assess what you will be doing with this car most of the time. XLR8STEVE's BMR setup is way overkill for the street. I fabbed a setup with a floating 5/8" bar and works superbly on the street.

Were I not able to fab what I did I would use this for a street car:

https://www.summitracing.com/parts/u.../gto/year/1968

I avoid the OEM style bars that bolt to the LCA- too much binding.

[Keith Seymore]

Originally Posted by DonnyD

. I know the factory 4 link isn’t the greatest. Thanks for the help.

Yah - I don't know why you say that.

Factory four link, boxed lowers, relocated uppers - I'm going 9.80's with 1.400 sixty foots.

Had a set of Hoosiers that wore down to the cords and the car still hooked.

K

[Keith Seymore]

Just to add to that:

A production four link is basically the same as a race car four link, except (a) you lack the adjustability for locating the instant center [ie, the production has one set of holes] and (b) the race four links are parallel to the centerline of the vehicle vs the production uppers are splayed to control axle lateral movement.

From the side they are the same concept.

K