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Modifying rubber engine mounts

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Im after some information on modifying standard rubber mounts to be abit more durable, I've heard of putting a bolt through the middle, can anyone elaborate?

 

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Dunno about that, the bolt will then take the load under tension, eliminating the cushioning effect of the rubber. It will thump around and something will break eventually.

The best idea I've seen is a spring shackle bush that goes into a tube that's welded to the engine bracket, and the shackle bolt goes through that and 2 end plates that attach to the chassis bracket (some designs vice-versa)

They are marketed as "unbreakable" and aren't cheap, but I can't see why you couldn't make your own.

https://m.ebay.com.au/itm/FORD-302-351-WINDSOR-CLEVELAND-PERFORMANCE-HEAVY-DUTY-ENGINE-MOUNT-393-408-XW-XY-/262466612237?nav=SEARCH

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Yeah, I been thinking about these, but $250 for engine mounts is re-fukkin-dick-uless. I guess it's just the cheap rubber they make them out of.

Maybe it's the torque twist of the Clevo............

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I know these are clevo but same principal. 3/8 UNC countersunk , set nyloc as tight or loose as you need . I have done with a rubber shocky rubber under the but gives some cushion.

IMG_1528.jpg

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Be very careful with the aftermarket styles that use nolathane bushes, especially on a toughie. I've recently re-designed the engine mounts I was doing (Ryno mounts) due to stuff that I've found when dyno tuning cars with solid mounts or nolathane style mounts. 

I once thought solid mounts or those Neo style ones were they way to go, but I'm now 100% convinced that it's not. You need dampening of rubber. Mods like the ones Dean has done is very common in speedway and they make the standard mounts last.  That mod is way cheaper and effective than an aftermarket mount. 

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22 minutes ago, ando76 said:

Be very careful with the aftermarket styles that use nolathane bushes, especially on a toughie. I've recently re-designed the engine mounts I was doing (Ryno mounts) due to stuff that I've found when dyno tuning cars with solid mounts or nolathane style mounts. 

I once thought solid mounts or those Neo style ones were they way to go, but I'm now 100% convinced that it's not. You need dampening of rubber. Mods like the ones Dean has done is very common in speedway and they make the standard mounts last.  That mod is way cheaper and effective than an aftermarket mount. 

what stuff have you found?
BGDAV's 408 runs them, would be keen to keep an eye on issues before they happen

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I know these are clevo but same principal. 3/8 UNC countersunk , set nyloc as tight or loose as you need . I have done with a rubber shocky rubber under the but gives some cushion.
IMG_1528.jpg.caef3703a16eee273e1cb44d99b236c4.jpg
I think the rubber shock mount thing is the key here. The problem with simply bolting through is that it's fine under compression, but under tension it will be excessively harsh. It will also flog out eventually. Having that shock mount, as you say, allows cushioning in both directions.

Ando is the problem snapping mount lugs off the block?

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Nah it's a tune issue. The rigidness of those styles is one of the things that leads to chronic fuel pull over.  Type fuel pull over into you tube and you will see what I'm talking about.  

After much research I've found a way to totally eliminate it. There are plenty of products on the market aimed at curing it, but they are all based around mods to the carb. None of them truly eliminate it.  What I have done does. The cars idle and start better, are way easier to tune and make more power.  No more 'tune out as best as you can and send it out, the customer will never know'.  

The four barrel kit will be available early next year as I'm happy with the endurance testing now.  The main part of the  2 barrel kits have been machined and are on their way back from Malaysia.  Sadly we had to send them overseas as making them here was just not viable. 

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Could only find vids for squirter pullover, which i assume is unrelated to what you're talking about Ando. Is it a cornering issue on circle track cars?

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Yep. That's it. Fuel pullover through the squirters. It does chronic things to mixtures and afr as outlined in old mates you tube video. 

It turns the accelerator pump squirters into a fuel injector. They just go open circuit. It's one of the most bizarre things I've seen on the dyno. Had a 2 barrel and 4 barrel crossy both do it.  Last time I was at Boetchhers on their hub dyno, Brenton their main brain and engine dude couldn't believe it.  He actually made me run the car up a couple of times so he could video it.  It's not something that occurs on their big dollar, US sourced v8's.  It actually does occur on very high revving v8 engines. 

 

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I know you say you have fixed it through the mounts but I’m curious to know about the airstream. Does it change through the rev range? Did anyone try running some sort of smoke or gas like in a wind tunnel?

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The mounts are only one part of the whole system to address the actual cause.  All the rest of the stuff, like he talks about at the end of the video, just treats the symptoms. 

Through each step we were able to lift the rpm point at which it started to 'pull over' but it wasn't until a big bit of lateral thinking happened, and yes it did involve several beers, that we actually cured it. I say we as Dave from Clarko's Performance was part of the process as it was his 2 barrel mud flicker that started the journey. Cam also played a part as did Brenton from Boetchhers and even my nephew who is studying mechanical engineering. Josh has also,played a massive part as he has been doing the endurance testing of the four barrel kit.  I like to ensure the function and durability of all the products I develop before I try and retail them. 

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The amount of airspeed past the Venturi does have an effect on when it occurs. On Daves 2 barrel crossy, it was at 3500. They just went complete open circuit and poured the fuel in.  Being a restrictor class engine it's forced to run the visually standard manifold and 350 Holley. It runs one of Cams heads so the airspeed is just ridiculous off the bottom. Which obviously made it ten times worse. 

 

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They sell "anti-pullover" squirters through Holley, Quickfuel, etc that have tiny shrouds cast into the part that is designed to create a stagnant pocket next to the outlets that prevents air from rushing past them and pulling fuel out.

I had one but used it on a mate's car. They come in the same sizes as the old type.

Old type & anti-pullover:c0d3b99681f933d978527701009004ea.jpg31504a2401c1c020876dc7be99f61e1d.jpg9930884a43825432c52f3836da1a4cfb.jpg

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Yep. And they are part of the solution we have come up with, but they still pull over. It's not as bad, but it still happens as the route cause is still there, no matter what part you fit to the carb. 

BLP carb in America sell a whole lot of stuff aimed at dealing with it. Yes they help, but they don't eliminate it. You don't want to know how much it cost to learn that fact. 

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Oh yes Q. You have that right. Life would be a lot easier with them. Oh wait a minute. I have them.  Lol. 

Most of my customers still love carbs and it's really hard to get them to commit to efi on these things.  I do however have a bloke keen on fitting the heritage series Jenvey efi throttle bodies to his 250 2v. 

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