Hot Rods XO/PP Bonneville project

Rain this morning but clearing around 10: 00
Had issues with Toe on the truck and will address that this morning after the rain stops. Should get some runs in this afternoon.
Stay tuned!

 

A little wet but clearing out

 

Hope the weather straightens out for you.

 

OK here is a summary of the last two days. On Thursday on a shakedown test we found the truck had a very bad shimmy in the front end. We worked on it enough to get it through tech. On Friday it was raining until noon and find the problem was still there. We worked all afternoon and around Six We finally figured it out. We are ready to set new records. Stay tuned

 

Weather tomorrow will be 80s and clear
Looks like a good day to race.

 

After chasing the front end shimmy/deth Wobble we are not able to find the cause.
We thought we had it fixed but didn't.
So we are homeward bound with no passes at the Arkansas mile.
Always next time..
Thank you all for following just know it ain't over

 

Damnit…So sorry to hear this. In the words of my 88 year old friend, “I may F’…k Up, but I’ll never Quit.” Keep after it!!

 

Sorry you had a problem. Hope you figure it out..

 

That's to bad, what has changed since last on track that could cause this?

 

Do you have a steering damper, like a Fiero or VW Microbus?
Did you put a "U" in the tie rod when you lowered the vehicle?

 

I admit not being familiar with Ford trucks of the vintage of your's, but wonder, is it a solid beam axle or is it new enough that it might have the twin-I-beam design?

Lynn

 

You’re right, I don’t hear the fat lady singing. He he.

 

We don't currently have a damper, but we will be adding one. The tie rod is still straight. Toe in is correct.

It was nice to meet you at Blytheville!

The truck came with a straight axle and parallel leaf springs. It now has a dropped straight axle, hairpins and coil overs. Steering consists of the factory box raised 5 inches, stock drag link and stock tie rod with tie rod drop blocks. We will be rebuilding the gear box, adding a damper and replacing the drag link. The tie rods are new.

One thing we will look at is the steering box location. We raised the box 5 inches when we lowered it the first time to keep the steering geometry as the factory designed. Basically we raised the box the same distance that we lowered the truck which was about 5 inches. Last year we lowered the truck an additional three to four inches, but didn't move the box position, putting the drag link in an upward direction from the pitman arm to the steering link.

Also the the right shock appears to have an issue. We checked the spring adjustment and positioned the adjustment and lock rings in the same position side to side. After that it seems the right side may be bottoming out so maybe the seal's blown. Wont know for sure until we take the whole front end apart.

 

@Pete Eastwood , starting at post #1891, top of page 64.
Any way to help these guys with steering problem?

 

I'm sure you'll find the problem. I asked about the front end arrangement mostly because I'm not a fan of the twin I-beam setup that would have had an effect on camber when you lowered the truck the additional few inches, but since you have a drop straight axle my feebel idea is out the window.
I am quite curious now though what the problem might be and hope you'll post follow up as things get checked out.

It was great to meet someone I "knew" at Blytheville.

Lynn

 

If it is still ill handling after adding the damper look at the tie rod "drop blocks" which I presume to mean spacers between the steering arms and the tie rod ball joint ends. Those could cause the tie rod to resonate like a bass fiddle string.

 

Now that I have had time to think about the trip to Arkansas I want to apologize first to my crew.
I should have been more prepared for the mile and fell short. My apologies as well to all who have supported the 640 project.
The XO/PP record at Bonneville has been bumped to 140 and change
Putting it totally out of reach for our little 270 Cu. In. Engine. We are 50 cu. In.
Under the GMC.
It cost around $8000 to do the trip to Bonneville and with the record set out of reach we will not be returning to Bonneville with the current engine platform. We are developing a GMC engine platform for future attempts at Bonneville just not sure what class at this point. We are still going to run the 270 Ford engine platform at the Arkansas mile once we sort out the front end problems.
Not giving up just adjusting our direction.
Stay tuned..

 

The sheetmetal intake for the 302 GMC is welded up and ready for powder coat

 

So****y I would leave it alone!

 

It does look great like this but the salt is so corrosive that I will have it powdercoated in clear.

 

I pulled the front shocks today and inspected them closely. Found them good and reset them as built then I found the right tie rod drop loose and torqued it and will tack weld them just enough that it can't move. It's now set up on the alignment casters and ready for alignment.

 

Been working on this dyno simulation for a couple months. Many changes in its components to come up with this engine design.
320 cu. In. GMC for Dave Russell this one is going to be a bad****. Now just need to find the money to bring it into reality. Many custom parts to have made.

 

How hard do they turn these GMCs?

 

If to be believed . . . it tapers off at 11 grand(?).

 

So you’re saying this goes to 11?

 

. . . that's what the report says.

 

I ran the simulation that high just to look at the curve. I know in reality it will never see that rpm. looking at moving the power band down and looking for a wider power band it will lose overall power numbers but will have much more usable power. Still playing with the cam profiles to work to 7000 rpm No more. There's more to it than just numbers.

 

I’m pretty sure somewhere in that simulation should be the “run over the crank” moment!

 

Just a little background here, I have built several engines using this program for over 30 years that were successful. My engines have won on the oval resulting in track championships in grand stock and mini stock as well as track records in drag racing the overkill engine that Jim McClure set a world record of 241 on his Harley top fuel bike in the late 80s was designed with this program.
This is the same technology used by many NASCAR engine developments over the years.

 

Does the 116% vol eff mean you are going to boost the engine, or is that the result of some kind of ram induction at speed?