Hi, sorry for my late reply. Thanks for the idea. So you think that the best is to open only one side of the frame to the bushing outside diameter and not both sides? Why leaving the bushing 1/4" protruding out from the frame? If I leave the bushing protruding out from the frame then how I am going to slide the reinforcement in?

The reinforcement I am thinking of doing it like as an S shape - to start from the highest part of the frame rail where the 3 bolts holds the top triangulated shape bump stop all the way down to the lowest horizontal part of the frame rail where there is the back seat belt bolt.

I will first fabricate the S shape sides of the frame using 3mm thickness mild steel, then weld the bottom part to become a U shape reinforcement. Then this piece will be bolted to the frame with the bushings you mentioned. To this reinforcement I will weld the ridetech top arm.

I do not know if it will be good or not - just thinking how to do it.

I was thinking of leave only 1/16" of bushing protruding out then weld it all round and grind it flash. But my worry of grinding it flash will be that by doing this I will weaken the weld. Any ideas please?

These are the bushings?

 

Hi All, I am at the end of my work trip at Dubai finally. Flying out in 2 days.
5 weeks away from home, family, Camaro, etc......


The plan for the Camaro when I return home will be:-


Install the stock front frame
Install the stock rear end
Install fenders
Prepare it to take it to the sheet metal finally.


Does anyone know how much torque I need to put on the lower frame mounting bolts?


Thanks

 

Factory manual says 75-90 ft. lbs. torque.

 

Thank you.


Finally I am home back with my family.

 

Back to Rear End Calculations.....Lately I carried out some rear end calculations of a ford 9" rear end having gear ratios of 3.00, 3.25, 3.40, 3.50, 3.55, 3.60, 3.70 and 3.89 using known standard TH400 gears (2.48, 1.48, 1) and 295/35/18 tyres for the rear. I did this using Microsoft excel basic equations. One just need to put the tyre ratio on the red field of the tyre as well the ratio desired of the rear end where is the red field of the rear end ratio. This should calculate the tyre circumference, overall height, final gear ratio, tyre movement in inches per one engine revolution. I found this very helpful and wished to share this with you. Maybe some one can try it and get feedback from you as well.


I am trying to find a way to attach/upload this document to the website but I do not know how.....

 

There are actually several calculator sites on line that will do it all for you. Pretty easy, and quick if you know your tire diameter. Here's one I use:
Engine RPM Calculator

Another good one:
Engine RPM / Engine Speed Calculator

Another:
Calculators

 

Managed to do it. Just click in the link and download it and then save it to the desk top. Hope you like it.


https://drive.google.com/file/d/0BwmM_J0DFw9mOVNFaHZHdTFzRDA/view?usp=sharing

 

Hi, thanks for the calculators. I did the excel worksheet so I will understand how the calculations are being done and also to be able to understand the concept of the gears better.


I am really confused which rear end ratio I have to choose for my 9" ford. A friend of mine had ford 9" with 3.9 gears and he swapped it with 3.2 gears. He told me that with 3.9 gears, it was too low and the engine was revving high. With the 3.2 he is really happy and the engine is too. The gears will not shift fast. He told me that if the engine is going to be powerful, 3.00 will be even better.


The engine builder recommended 3.5 gears for the rear end. If I use 3.2 or 3.0 gears, do I put stress on the engine or gearbox when in the first gear?

 

I agree with your friend, and if your car sees much driving at speeds around 60 mph or higher, the 3.90 gears are too low; especially with low profile rear tires! I have 3.73 gears on both of my cars, and my BBC powered '63 Falcon has 30" rear tires. It's not wound too tight at 60 mph, but I don't do much of that. My '46 Austin with SBC 355 has 28" rear tires, and is a bit higher rpm, but the SBC likes to wind, and it's still under 3,000 rpm, so OK.
If your engine builder recommends a 3.5 rear gear, does he know your tire diameter and transmission when he made the recommendation? If he has all your info for trans and tires, then I wouldn't stray far from his choice for gears. Depending on tire diameter, the 3.50 gears could be just right, or if your tire diameter is less than 28", a bit too low.
Considering the amount of torque and HP your engine will make, I doubt you'll see any issues with a taller 3.20 gear ratio vs. 3.50 If you drive mainly around town, I'd go 3.50, and if more is 55-60 mph driving, I'd go 3.2 ratio.

 

Here on the island our driving speed is limited to 43mph because the radar cameras on the streets are limited to 43mph. So let say that our "cruising speed" will be of 43 mph.


My tyres are Toyo 295/35/18. This will be a diameter of 26" and having a circumference of 82 inches.


I made the calculations below of the 4 gear ratios of 3.00, 3.25, 3.50 and 3.89 with the engine RPM at 43mph cruising speed on the final gear of the TH400 (1:1). As well there is the distance the tyre will move on the final gear.


1) 3.00 gears @ 43mph = 1659 engine RPM and 27 inches of tyre movement at the third gear.


2) 3.25 gears @ 43mph = 1797 engine RPM and 25 inches of tyre movement at the third gear.


3) 3.50 gears @ 43mph = 1935 engine RPM and 23 inches of tyre movement at the third gear.


4) 3.89 gears @ 43mph = 2151 engine RPM. and 21 inches of tyre movement at the third gear.




My friend tyre is 255/60/15. This tyre will be a diameter of 27" and having a circumference of 85 inches. His engine is 454 and rated 400 Hp. So calculations:-


1) 3.23 gears @ 43mph = 1725 engine RPM and 26 inches of tyre movement at the third gear.


Comparing my friend rear end ratio and tyre combination, the closest figures will be of the 3.25 gear set for my combination. Considering that my engine will be more powerful, I rather go to the 3.00 gear set.


What do you think about the above?


In the mean time, I will get in contact with Tom Nelson and discuss this again. As soon as I sort this out, I will place my order for the Moser rear end finally