V8 rear suspension

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C.Costine
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Re: V8 rear suspension

Post by C.Costine » Wed Jun 19, 2019 2:38 pm

I have experienced some pretty mean wheel hop with my Ford 9000. It took two weeks for my back to recover. Firestone told me to let some air out. But that was pulling the transfer sled on the tractor pulling track so there is probably not a lot that transfers, LOL.
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Re: V8 rear suspension

Post by RCMike » Wed Jun 19, 2019 3:10 pm

If strip passes with slicks on a prepared track are in the plans, I would highly recommend a welded diff and bigger axles. The stock simply will not live. And when they go, it can be ugly..



.

If you are going to stick with the stock axles, I would strongly suggest a jump to the Summer's Brothers with 1/2 inch studs.. You will need them.

Flares are available. They don't ship particularly well, but I can try.

As you probably know if you are a drag racer, axle hop is the killer. Make sure you go cleanly into wheelspin, or step out of it. Because the components on the roadster are simply not designed for the shock loads of axle hop. Things go bad fast.

Anyway, good luck with the project, and it looks like fun! I admit, I like to turn too much to go drag racing, but I do love to go watch the fuel cars twice a year..

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Re: V8 rear suspension

Post by speedbug78 » Wed Jun 19, 2019 6:36 pm

Ouch is right. I hope you were ok after that. Yes, axle hop and tire shake both really break stuff. I don't have enough power to tire shake so I'm good there :)
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Re: V8 rear suspension

Post by speedbug78 » Wed Jun 19, 2019 10:20 pm

Well I moved enough stuff out of the way to get the Datsun into my lift bay. The tires I've got are 295's though. Guess I need to go shopping. Looks like I can build the 9" and buy almost everything else I need for racing just for the price of rear end parts on the original.
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Alvin
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Re: V8 rear suspension

Post by Alvin » Wed Jun 19, 2019 10:55 pm

speedbug78 wrote:
Wed Jun 19, 2019 10:20 pm
Looks like I can build the 9" and buy almost everything else I need for racing just for the price of rear end parts on the original.

Lift_Datsun.jpeg
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speedbug78
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Re: V8 rear suspension

Post by speedbug78 » Wed Jun 19, 2019 11:04 pm

Drag program shows 10.9's with the M/T tires suggested earlier. If things go really well I might just squeak into the 11's.

Edit: Oops I forgot to add my own fatness in there. Fixed now.
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Last edited by speedbug78 on Wed Jun 19, 2019 11:15 pm, edited 2 times in total.
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speedbug78
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Re: V8 rear suspension

Post by speedbug78 » Wed Jun 19, 2019 11:05 pm

Well what do you need us for then!
For all the great ideas and perspectives you have!
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spl310
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Re: V8 rear suspension

Post by spl310 » Thu Jun 20, 2019 6:23 am

You could probably do ok with an 8" if you want to save a little weight
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Re: V8 rear suspension

Post by jhayden » Thu Jun 20, 2019 8:54 am

Happy to be proven wrong about the degree of interest in drag racing among members here -- certainly more than I reckoned!

With apologies for semi-hijack of this thread:

"Me Me Me oooh I can discuss drag racing!!! :lol: "

True story and Fond memory: A colleague once confided in me that after class she had asked a student to hold back a bit to allow others to respond to her questions. The young man (who was only twelve or thirteen at the time and actually was very courteous) had earned early admission to the college and the class through testing. He responded that, “But, Ms. _____, I counted to ten before answering as you requested before.”

Especially remarkable in that it was a Calculus III (Cal I and II prereq) class.

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speedbug78
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Re: V8 rear suspension

Post by speedbug78 » Thu Jun 20, 2019 10:20 am

You could probably do ok with an 8" if you want to save a little weight
You know this has been suggested to me several times and probably the right thing to do. I've just been a bit blinded having the 9" sitting in my way and not having an 8.8. Anyone want to trade me an 8.8 for a 9"? :wink:
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Re: V8 rear suspension

Post by fj20spl311 » Thu Jun 20, 2019 10:54 am

You are going to invest a lot of cash / time to make the rear axle fit properly. I would start with an 8.8 with disc brakes. You should be able to get one from the junk / recycle yard for very little. If you are lucky, it will have a truetrac and gears near 3.73. I would not worry about breaking the rear axle, you just don't have the traction.
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Re: V8 rear suspension

Post by speedbug78 » Thu Jun 20, 2019 11:06 am

Agreed, although it is interesting that in a car this light, DD is predicting better times with a rear gear near 3.00. Too much time shifting with a higher ratio gear.
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Re: V8 rear suspension

Post by spl310 » Thu Jun 20, 2019 12:44 pm

I meant an 8". not an 8.8". For that matter, you may be OK with a 7.5" It all depends on how hard you launch and how frequently.
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Re: V8 rear suspension

Post by speedbug78 » Thu Jun 20, 2019 4:32 pm

stl310 - sorry for misunderstanding, I just assumed you were talking 8.8. I've been looking at what people say about these options, but it's really difficult to separate the facts. Here's what I've got though:

H190? Rear end, weight unknown, probably pretty darn light. Someone quoted $1200 for an LSD on this axle. Then I'd need aftermarket axles, not sure where to get them. Should be $350+ at least.

9" = Heavy ~200lbs. Would cost me ~$640 for the major parts I'm missing (LSD, axles). More money can go lighter on housing (5-10 lbs maybe?), center ~20 lbs with aluminum , brakes 20? lbs possibly much more. Spool saves $$ and 15lbs.

8.8" = Some say 199 lbs, others 167 lbs, similar cost. Not as many options to make it lighter

8" = 170 lbs, most of the weight savings over the 9" is the brakes https://www.jalopyjournal.com/forum/thr ... ht.301890/ is an aluminum third available?

7.5" = The only weight I could find was 130lbs. Mustang guys say don't race with them. I don't relish breaking a rear axle as eventually I'd like to drive this car to the track.
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Re: V8 rear suspension

Post by spl310 » Thu Jun 20, 2019 5:34 pm

I'm not able to look now, but I think there's an aluminum chunk for the 8"
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