underside pic

 

here is the top view:

 

here is the LIM:

coated in matte black which is the best in terms of heat insulation, but is the fugliest one by far.....

 

Another school of thought to port and removed those butterflies is to reduce turbulence........ which at high RPMs makes a difference........

 

Damn it. 3 years ago I never would have thought to remove that little divider. I guess it was because I thought I may need it

 

doh!!!!

 

mine looks similar to those with it ported out....

-Nic

 

I ported my TB bridge out and ported/polished the interior. I actually poslished ALL intake and exhaust surfaces!

Here is a pic of the UIM

https://www.rx7club.com/forum/attach...&postid=908524

I also tapered the rear of the TB between the 2ndary bores and rounded/relieved the front a bit so it was smooth flowing.

TB rear

https://www.rx7club.com/forum/attach...&postid=908537

TB front

https://www.rx7club.com/forum/attach...&postid=908531

I have more pics of the manifolds and have some tips on porting/polishing the runners if there is interest.

The manifolds flow great with very quick response both off and on boost. The only problem I have had is I have to run more fuel on cold start as my extended port is pushing the air fuel charge up into the LIM and the polished surfaces whet very easily when cold.

Ian

 

Did you port the throttle? It looks like the stock size

Very nice polishing by the way

 

The exposed metal in the case of the UIM is aluminum and will not corrode. There will only be light oxidation.

This is a debatable benefit. The air inside the UIM will be warmer than the air on the outside in the area above it. However, the temperature of the air underneath the UIM may be higher than the temperature of the air inside the UIM.

Then there is also the issues of heat soak of the UIM.

So, what is the effect of ceramic coating the UIM? Keeping the heat in or keeping it out? I think that this question is very difficult to answer without doing scientific data collection.

 

Ian, I would love those porting/polishing tips you have offered!
Thanks

 

Indeed it is moot.

UIM inside temps depend on the IC...........

 

Like batboy said, the inside temp of the UIM will be that of the air out of the IC. If a certain piece of metal in the engine compartment is cooler than the rest, then that piece of metal will act like a heatsink. Exhaust and engine temps will always be higher than the air coming out of the IC, and a lot of that heat is transfered over to the UIM. Coating it will help prevent an X amount of heat from transfering itself to the UIM.

I wonder how a big heat shield would look under the UIM

 

The uim heatsoaking issue doesnt come from the air around the uim, it comes from the chain of parts connected to the engine. The engine heats the lim bacause they are directly connected, there really isnt anything you can do about that.....and similarly the lim heats the uim because they are also connected. The engine heat is transfered thru the chain of metal to metal contact. Something I wondered about is if using a very thick rubber gasket between the lim and uim would help with this.

Also, anyone basing thier cooling info and air temps on the stock air sensor will be wrong. The stock air sensor gets heatsoaked just like the uim. If you really want it to be functional then relocate it to the greddy elbow. With it being in the uim, its prob telling you the temp of the uim not the air passing thru it.

I also dont think that coating the uim will help with the heatsoak from the lim. And like Max, I think once it is heatsoaked from the lim its not going to cool off as fast because the coating is insulating the uim.

I looks nice though!!!!

just my .02

STEPHEN

 

^ My point exactly, although it is better expounded by SPOautos.

 

Here are a few ways heat moves around:

- per SPO AUtos, heat is conducted

- Heat is radiated

- convection

All of these conditions exist in the engine bay......... it's less of an issue when the car is moving and when air is moving in the IMs.

 

Batman, those are some great pics. I have the UIM off right now, and I'm looking to polish it. Are there any advantages to removing the butterflies while I'm at it?

 

Thanks to my Nikon N90s camera (not some POS digital crap).....

The advantage in removing the butterflies and opening up the port is to reduce turbulence and increase airflow.

Naturally this is most noticable at higher boost levels......

Dimcorner had this done and might have a dyno comparison from stock to ported UIM/LIM to document the difference........ if anyone like to share their results they are more then welcome..

 

Ian,

I too would be very interested in the information on porting and polishing. Maybe you should create a new thread that can be archived on the subject. Your UIM, and TB look great.

Dale

 

AutoSpeed did an article on Manifold Insulators that is very interesting.

http://www.autospeed.com/A_0401/page1.html

Phenolic spacers insulated between the intake manifold and the heads reduced the intake temp by 30 F. A while ago I contacted Outlaw Engineering and he said they could make an insulated spacer for the FD, but would need someone's car to fit the initial one.

http://www.outlaw-engineering.com

Anybody near Noblesville, IN 46060?

sales@outlaw-engineering.com

The suggestion was between the LIM and UIM and new studs would be needed, but couls be part of the kit.

 

CYMREX,

I like that........ maybe we can do a group buy on that.

Who's going to take a shot at that?

 

Ok, thanks batman. Since I don't get on the throttle before the car is warm, I think I will remove the butterflies while the UIM is off. I'm going to have it polished too.

 

This is what I found after removing my butterfly my car stop the hestaition, also I have the lower intake jet hot and exhasut manifold mate in jet hot black and all I notice is reduce of under hood temps, for performance wise I never notice my boost kick earlier it would be nice though. Also for the hestaition I did had the 2 extra ground strap and I still have the hestaition.

 

I'm down for some Phenolic spacers! Any idea what they would cost?
Someone get this thing in motion

 

add me to the phenolics list