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V8 Conversion Gearbox mount reinforcement

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OK Zed freaks.

For all those who are doing or have done V8 conversions this might be of interest.

I have had a nagging vibration in my Zed only when the car was under massive load doing over 160klms. Crusing over 200klms was nothing. But I was in search of a solution.

Anyway I have had Andrew at the old Merridian Motor Sport make up some awesome brackets to be welded in between the Chassis rail and the gearbox mount. end result is per attached ready for a complete weld in.

You will notice the left side the floor pan is level but the right one has sagged around 10mm due to the twisting torque of the engine. Anyway this boxing of the brackets will lock in and secure these mounts rock solid.

I highly recomend this for anyone putting in a V8 with some descent power.

Cheers  :D

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No I haven't taken it for a drive yet.

I may not get the car back till early next week. Then I will have to find a time and place to take it up to 200klms and test it.

One other issue we addressed was the rubber in the standard crossmember (Bolt Fastening). It is next to useless for anything other than standard application. Even then I would say it is questionable given the gaps around the rubbers. So we pressed out the standard rubber ones and inserted nolthane bush's.

So stay tuned I guess and all things going well I will have fixed my problem.  ;)

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Thanks Craig.

 

Keep us posted once driven at a legal venue ;D

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Craig

 

So it is not a structural issue of itself but rather a flex issue causing a misalignment of the tailshaft and an imbalance at certain revolutions?

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OK Zed freaks.

For all those who are doing or have done V8 conversions this might be of interest.

I have had a nagging vibration in my Zed only when the car was under massive load doing over 160klms. Crusing over 200klms was nothing. But I was in search of a solution.

Anyway I have had Andrew at the old Merridian Motor Sport make up some awesome brackets to be welded in between the Chassis rail and the gearbox mount. end result is per attached ready for a complete weld in.

You will notice the left side the floor pan is level but the right one has sagged around 10mm due to the twisting torque of the engine. Anyway this boxing of the brackets will lock in and secure these mounts rock solid.

I highly recomend this for anyone putting in a V8 with some descent power.

Cheers  :D

 

Have not noticed any vibration at any speed, but i replaced my whole chassis,what setup are you running (engine & box) ?

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Hi Peter,

Well it is a sort of structuralFlex thing combined to do with the tunnel vebrating under heavy load. So everything has now been strangthened and welded in. Everything was in alignment and perfectly balanced. I guess 750nm of torque in the tunnel is to much for the flimsy sheet metal to take. So as per photo's it is locked in. I am picking the car up shortly and will maybe get a test drive in over the weekend. Remember like I said earlier if not under full acceleration I never got any vibration. Just at full throttle at certain speeds.

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I guess 750nm of torque in the tunnel is to much

 

750nm .....Farking...Clarkson knows

 

How many powers Craig?

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Craig,  that is a 300 plus KMH at the Island now with that mod, Never ends does it? that vibration i would also be ckecking to see if the vibration caused areas in the body to crack or deform have a really good look and attend to them at the same time before they open up further. yYour car looks great and goes too, but in 1976 I dont think nissan would ever think that their cars would end up with 600hp V8 sprint car motors in them, in comparision that 2.6 litre is a lame donkey

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Mmm yup, check where the front rail overlap finishes just behind the firewall, under the floor rails...

This is where both of my cars and most others I've seen crack, ESP with only a mild dose of twist.

You may need to up spec or reo the floor rails too! Unless your cage has this all covered.

Nice Tq no.s too...

Nato

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Morning Gents,

Thanks for the advise Daz & Nato I will have to check the front fire wall and a few other areas for cracks when next on a hoist. I am hoping no issues due to the 8 point cage. I don't have quite 600bhp but maybe one day. Ha

Well I only drove the car home but managed to give it a few bursts and found the car to feel a lot better. I am pretty sure I have fixed my problem. So for those chasing their tail re vibration like I have for years this is a good area to look at. Especially since my engine was moved back so far. While this gave me prefect weight on all 4 wheels it did leave most of the weight of the engine & gear box hanging on at the tunnel.

Anyway happy days and I can now move onto the next project being the oil cooler then my 7 new gauges from the states that I have been sitting on for years. Complete with Tacho with progressive led shift lights and GPS speedo to 300klms. Then I will finally know how fast I am really going when I wind it off the clock back to the zero ha ha. Ah those are the days.  ;D

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Andrew was pretty well priced for the quality of work. I found his work ethic and attention to detail great. He took the time to explain our strategy to over come the problem, took progressive photo's of the car and itemised his hours by stages as he went. I have the car booked in again in a months time to get some minor upgrades to the exhaust and engine mounts. He is pretty busy though if you wanted some work done.  ;)

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my 7 new gauges from the states that I have been sitting on for years. Complete with Tacho with progressive led shift lights and GPS speedo to 300klms.

 

Speedhut?

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Can't remember the brand. Pretty sure Speehut. I got them to light up in red at night. Something a little different to match in the car. Not practicle but hardly drive the car at night so should be OK.

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All tested. Took the car for a fang and up over 200klms. Car felt great. All my problems solved. The car is a joy to drive these days.  :)

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