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Rotary Sprite
- Thread starter DWeeB
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OP
DWeeB
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I went for a drive today and noticed a puddle of oil near the rear wheel. Inspection revealed a leaking rear shock. I was thinking of replacing the lever type shocks with a tube step up. Has anyone tried one of them e-bay kits. It looks like there is an awful lot of under hang from the lower tube brackets. Should I just replace the lever types? Just was trying to figure the pro's and cons.
Jim_Gruber
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Peter C's shocks don't leak. For the price of a pair of lever shocks guaranteed to work you can't duplicate that in a Tube Shock Kit. NFI, just a very satisfied customer for the last 12 years.
nosimport@mailbag.com
Peter Caldwell
World Wide Auto Parts
2517 Seiferth Rd., Madison, WI 53716
(800) 362-1025 Fax (608) 223-9403
nosimport@mailbag.com
Peter Caldwell
World Wide Auto Parts
2517 Seiferth Rd., Madison, WI 53716
(800) 362-1025 Fax (608) 223-9403
OP
DWeeB
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I got the rear lever shocks as suggested and while removing the old ones I found out what happened to the original one that was leaking. Come to find out the 2-1/2" tail pipe I made was a bit to close and melted the lever seal. So I'm fabricating a heat shield to alleviate this. I also noted the cloth axle stop straps are pretty much spent. Any tips for replacing these?
Trevor Jessie
Yoda
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I think the original only had some type of packing material. If you got shocks from Peter, I think they have some sort of synthetic material sealing them.
Rotary engine heat on a shock of any sort is bad because it will thin the oil and reduce dampening.
Rotary engine heat on a shock of any sort is bad because it will thin the oil and reduce dampening.
Jim_Gruber
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Time and money Jack. When you have the time you usually don't have the money.
OP
DWeeB
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Trevor Jessie said:
Yeah I thought three inches away was safe but that was wishful thinking. The new shocks look like rubber seals so I'm building a new heat shield from a chunk of an exhaust shield I found on the road one day. I'll band that to the pipe with stainless banding and see if that does it. I really don't want to move the pipe since the placement of the fuel cell could be compromised and then a chain reaction from there.
OP
DWeeB
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Well I finished up the shocks and shields and I hope this works. I also dapped the shock body, axle casing and brake lines with thermal paint so I can see how hot these areas get when I'm up to operating temperature. This paint changes different colors depend on the temperature the surface it is on. This will give me an idea of the heat range these items are enduring to ensure I'm not over heating other components.
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DWeeB
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jgrewe said:
The header is working awesome John. I actually had enough pieces left over to make a second one with duel outlets. I will have to make a few clearance cuts and lift the motor to get it installed. I'd like to run a duel exhaust so I can decrease the pipe size and install a few silencers. I'm thinking that two 2" pipes will help me tuck the silencers closer to the floor. With 2-1/2 pipe the silencer hits the floor and hangs down to far. The question is do I have to have to have a cross over pipe to equalize the flow or can I run separate pipes and mufflers?
Before you start figuring out how to shove 16' of exhaust under the car be sure to plan for heat shields everywhere. Go take a look under any RX7, the entire length of the system is isolated by aluminum shields that are set off the body about 1/2" with limited attaching points.
There are three ways to transfer heat; conduction, convection and radiation. You need to do everything you can to isolate that exhaust pipe from the chassis with dead air space and something that reflects the heat. Header wrap is OK but an air gap behind a shiny aluminum shield is WAY better.
As for the design of the exhaust for performance, it is best to bring the exhaust together with a collector at one of three primary lenghts. The numbers are somewhere around 22-24", 84-86", and 120-123". (You should double check those longer numbers on the RX forum, the numbers are kind of foggy in my head right now but they give you an idea of what magic you will need to do to fit a system under the car) Longer primaries are a little better on a street car because you get to use a few more pulse waves to help scavenge the engine at low RPM's.
Once you bring the exhaust together you can split it again for multiple mufflers if you wish. Most guys run short primaries racing so they can put a muffler under the floor of the car then another out back, all that to keep the car under 103db.
There are three ways to transfer heat; conduction, convection and radiation. You need to do everything you can to isolate that exhaust pipe from the chassis with dead air space and something that reflects the heat. Header wrap is OK but an air gap behind a shiny aluminum shield is WAY better.
As for the design of the exhaust for performance, it is best to bring the exhaust together with a collector at one of three primary lenghts. The numbers are somewhere around 22-24", 84-86", and 120-123". (You should double check those longer numbers on the RX forum, the numbers are kind of foggy in my head right now but they give you an idea of what magic you will need to do to fit a system under the car) Longer primaries are a little better on a street car because you get to use a few more pulse waves to help scavenge the engine at low RPM's.
Once you bring the exhaust together you can split it again for multiple mufflers if you wish. Most guys run short primaries racing so they can put a muffler under the floor of the car then another out back, all that to keep the car under 103db.
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DWeeB
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Well since you put it that way John I'll stick to the single pipe set-up. Currently my collector is about 20" down stream with a short transition piece to a RB silencer then a long run to muffler out the back. I might have to shield the axle casing as well I noticed a weeping axle seal on the same side as the leaking shock. I'll be pulling out the axles to check for rifling this winter so I guess I'll check on that then.
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DWeeB
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Well as predicted I finally snapped the original axle. I will admit I was doing a few donuts at the time and may have pushed it a bit to far. Lucky I was only a few miles from home so I just hitched a ride home, picked up an extra axle and went back and had it changed out in 15 minutes. I'm hoping to have better luck with winner circle axles I have been waiting to install. I got 1200 miles out of that original axle so I'm kinda surprised it lasted that long.
