Phenolic Spacers

[Zuffen]

Phenolic Spacers have come up a number of times on this Site but no one has really explored them.

I recently read an article on Auto Speed (here is the link http://autospeed.com:80/cms/A_110474/article.html ) which makes interesting reading.

I remember reading a thread where the member said he couldn't put his hand on top of the upper plenum after a drive due to the heat soak.

As I'm building a supercharged engine and can't fit an intercooler every degree I can keep out of the maniflod the better.

I contacted a supplier in Melbourne and he will make 12mm spacers to suit an inlet manifold gasket I sent him.

In the Group Purchases section you will find a Group buy under way. Currently at $70.00 per set of 2.

The only downside I see is we may have to replace our manifold mounting studs with longer ones (or bolts) to accomodate the extra thickness.

I plan on doing away with the MLS gaskets and use hi-temp silicone each side of the spacer.

Another thing I plan on is to cover the bottom of the manifld with phenolic material as this would stop the heat soak from the valley being radiated onto the bottom of the manifold.

I'm hoping to finalise the GP early next week, probably on the 16th, so if you want to be in on it please sign up.

 

[striker]

hmmm Rod, since the manifold flanges are cut in an angle would't that pose problems when the thicker gaskets are inserted regarding fitting?

how much higher does the manifold come in?

I have also got some nice insulating material for the lower end of the manifold.

One thing on you install btw, since you run a charger w/o intercooler, I can imagine you need the block and it's water system to get rid of some heat, instead of insulating the manifold completly. I have no experience in this btw just thinking out loud.

grtz Thomas

 

[Lextreme II]

No to deviate the topic but would ceramic coating help?

 

[Peewee]

I'm still putting these in my "if they are that good then why don't manufacturers use them" basket.

I'm not entirely convinced they do that much. Sure the intake manifold is cooler, but how about the intake air itself?

Looking at the amount of internal surface area a manifold has vs the amount of air passing over it vs the time it takes for air to go over the manifold I doubt the air would absorb much heat.

In my experience a with good cold air setup you'll only increase temps 3-5deg over ambient (my air temp sensor was in the middle of the manifold so ~6" from the head).

But, if you are only hoping to reduce the temps by 2-3deg, then you'll most likely get your goal.


As another test I wouldn't mind taping a temp probe to the top of the intake manifold and drive down the freeway, see what temp the manifold gets to the. For sure when idling it would get uber hot, but what about at speed where it matters?

 

[ed_ma61]

1uz vvti has them fitted stock

 

[Zuffen]

Even old Holden straight 6's used them.

I'd be happy to gain 10degrees!.

The spacer doesn't create a fit problem with the manifold like a normal V8 because the manifold drops down vertically onto the studs.

Most V8's have the maniflod bolts at an angle so it does cause aproblem.

I'm going to have a set made and see how they turn out. If OK I'll then see what I can do as a GP for 10 sets.

I figure we can make a small jig to hold the material at the correct angle so the holes are milled like an extension of the manifold.

 

[striker]

hmm if the price is good I might be up for a set then.... every degree counts if you want an effective system.

Still the angles is what concernes me though, you could have to mill the whole piece at an angle, even if the manifold drops straight over the bolts the ports are far from straight, so if you want a straight flow path from the mani into the head you must place the manifold ports closer together if you plan running anything inbetween them.....
in short: if my 3d thinking doesn't let me down at 1am, and you'd just place the manifold over a 5mm spacer you'd end up with a small chicane in the intake path.....

grtz Thomas

 

[pull_85]

does this replace gaskets?
and where to get new studs from? or just use bolts eaiser?
interested....

 

[Zuffen]

Striker,

You're right.

If we don't allow for the additional distance we will create a chicane!

I'm trying to have them machined on a wedge that suits the 1uz.

Once I get mine I will see how it fits and where we go from here.

 

[XR8tt]

I can get some 12mm [aprox] board used in electrical substations that will do the job.. It's heat proof, fire resistant and obviously insulates..
Have to be machined though??
Could be fitted between low and upper manifold..
Tmk Ceramic coating in this case could hold the heat IN ??
I wouldn't do it on inside either..

 

[striker]

I think even if you introduce a wedge in the insulator you will experience at least 1 extra bend in the intake. the only way to solve this completly is shaving the manifold or shaving the head. you can shave about 3 to 4mm of the manifold, which if the insulation is as good as it says should be quite sufficient. you only need to make sure the injectors seal in the manifold effectivly. that part you will lose when you shave 3mm

Grtz Thomas

 

[dragonhvu]

Tmk Ceramic coating in this case could hold the heat IN ??

you're right about that. the only thing you should ceramic coat, are headers.

 

[Zuffen]

I disagree.

It's very common to ceramic coat combustion chambers and pistons.

 

[XR8tt]

I disagree.

It's very common to ceramic coat combustion chambers and pistons.

Yep thats to keep heat away from these parts..
Coating an inlet imo would hold heat in...