Lakewood `J Bolt`slapper bars

Rory McNeil · 04-02-2017, 04:19 PM

I am putting a sreet/strip car together, and I have a pair of old Lakewood slapper bars laying around I would like to use. These have provisions for the J bolts , anybody use these in the past, and does the J bolt setup help enough to justify the cost and effort to find the J bolts and brackets (assuming Lakewood still offers them). Or should I not worry about the J bolts at all. It looks like they would help spread the load away from just the welds at the mounting plates.The car is nothing too radical, about 3800 pounds, mild 428 FE Ford and 4 speed, hope it runs 12s with mid 3 series gearing. Mainly hoping to avoid wheelhop with the 2 inch wide leaf springs. It looks like I will need to extend the bars a couple of inches to get the snubber under the front spring eye, sounds like that was a common issue with the Lakewood bars.

MAURICE BLENDHEIM · 04-02-2017, 06:03 PM

Rory…I would just use them the way they are with your additions and the flat plates with square u-bolts on the front. The "J" Bolts were used to adjust preload on the snubbers. They won't add any structural advantages to something that is already more than adequate for its application. Tuning the bar would mainly consist of clearances between the snubbers and the contact point on the leaf springs. With a multi leaf spring pack being more rigid than a mono leaf, you have that in your favour. You had that same bar on your 1970 Cobra-Jet car and you know how that worked. Your 59 with a similar drivetrain may work even a bit better if you can get enough tire under it. It might work as good as tree sap on a head gasket. Can't wait to see you driving it. The last time I seen you in one of those was driving without a windshield. MB

Bob Mulry · 04-02-2017, 07:05 PM

Hi Rory,

If that slapper bar doesn't reach and contact the spring under the spring eye, it will bend your spring....

The old trick was to extend the length of the bar so that the snubber contacted the spring eye.....

You can adjust the preload by changing the height of the snubber.....

Jack up the car by the body and change the length...

If it is still too far away, you can add pinion angle shims between the bottom of the spring and the slapper bar spring perch.....

If you can find the "J" bolts you should run them to spread out the load of lifting your car away from the spring perch (that's a lot of leverage on those welds)....

Also put the stiffest extension shock that you can find on the rear...

They work,
Bob

Mark Yacavone · 04-02-2017, 09:06 PM

Rory, I've got a set of those J-bolts you can have, if you want them.
I couldn't find the lower brackets, but they're not hard to fab up on a power brake or some kind of bending device.
Just let me know.
MY

rod butcher · 04-03-2017, 08:09 AM

Make sure you gusset the spring perch pads.

Bill Diehl · 04-03-2017, 02:19 PM

Quote:

Originally Posted by rod butcher

Make sure you gusset the spring perch pads.

^^^^^what he said...actually you only need to gusset the rear of the perch

04-02-2017, 04:19 PM	#1
Rory McNeil VIP Member Join Date: Jun 2007 Location: from Vancouver BC Canada, now in Nova Scotia Posts: 1,306 Likes: 308 Liked 1,081 Times in 297 Posts	Lakewood `J Bolt`slapper bars I am putting a sreet/strip car together, and I have a pair of old Lakewood slapper bars laying around I would like to use. These have provisions for the J bolts , anybody use these in the past, and does the J bolt setup help enough to justify the cost and effort to find the J bolts and brackets (assuming Lakewood still offers them). Or should I not worry about the J bolts at all. It looks like they would help spread the load away from just the welds at the mounting plates.The car is nothing too radical, about 3800 pounds, mild 428 FE Ford and 4 speed, hope it runs 12s with mid 3 series gearing. Mainly hoping to avoid wheelhop with the 2 inch wide leaf springs. It looks like I will need to extend the bars a couple of inches to get the snubber under the front spring eye, sounds like that was a common issue with the Lakewood bars. __________________ NHRA 6390 STK M/S 85 Mustang

04-02-2017, 06:03 PM	#2
MAURICE BLENDHEIM Senior Member Join Date: Jun 2011 Location: Langley (no igloos), British Columbia, Canada Posts: 566 Likes: 305 Liked 264 Times in 85 Posts	Re: Lakewood `J Bolt`slapper bars Rory…I would just use them the way they are with your additions and the flat plates with square u-bolts on the front. The "J" Bolts were used to adjust preload on the snubbers. They won't add any structural advantages to something that is already more than adequate for its application. Tuning the bar would mainly consist of clearances between the snubbers and the contact point on the leaf springs. With a multi leaf spring pack being more rigid than a mono leaf, you have that in your favour. You had that same bar on your 1970 Cobra-Jet car and you know how that worked. Your 59 with a similar drivetrain may work even a bit better if you can get enough tire under it. It might work as good as tree sap on a head gasket. Can't wait to see you driving it. The last time I seen you in one of those was driving without a windshield. MB Last edited by MAURICE BLENDHEIM; 04-02-2017 at 06:09 PM.

04-02-2017, 07:05 PM	#3
Bob Mulry VIP Member Join Date: Apr 2002 Location: Coarsegold, CA Posts: 1,016 Likes: 57 Liked 320 Times in 102 Posts	Re: Lakewood `J Bolt`slapper bars Hi Rory, If that slapper bar doesn't reach and contact the spring under the spring eye, it will bend your spring.... The old trick was to extend the length of the bar so that the snubber contacted the spring eye..... You can adjust the preload by changing the height of the snubber..... Jack up the car by the body and change the length... If it is still too far away, you can add pinion angle shims between the bottom of the spring and the slapper bar spring perch..... If you can find the "J" bolts you should run them to spread out the load of lifting your car away from the spring perch (that's a lot of leverage on those welds).... Also put the stiffest extension shock that you can find on the rear... They work, Bob __________________ Bob Mulry 7516 STK A & M Motorsports

04-02-2017, 09:06 PM	#4
Mark Yacavone Veteran Member Join Date: Mar 2002 Location: Miles From Nowhere Posts: 7,789 Likes: 2,878 Liked 5,077 Times in 1,935 Posts	Re: Lakewood `J Bolt`slapper bars Rory, I've got a set of those J-bolts you can have, if you want them. I couldn't find the lower brackets, but they're not hard to fab up on a power brake or some kind of bending device. Just let me know. MY __________________ "We are lucky we don't get as much Government as we pay for." Will Rogers

04-03-2017, 08:09 AM	#5
rod butcher Member Join Date: Dec 2005 Posts: 252 Likes: 297 Liked 132 Times in 27 Posts	Re: Lakewood `J Bolt`slapper bars Make sure you gusset the spring perch pads.