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-   -   Building PP housings : made holes, need advice on epoxy (https://www.rx7club.com/naturally-aspirated-performance-forum-220/building-pp-housings-made-holes-need-advice-epoxy-1087895/)

whizzybang 08-09-15 05:43 PM

2 Attachment(s)
Hi all, here is my first attempt at a pp. turned out as good as i need it.

Two questions before doing the real parts :

- what is the yello-ish epoxy racingbeat use in their housings ? Seems to be liquid at first, and that would be the best way to make a perfect seal in the water gallery

- do i put the epoxy first and then make the holes or do i make the holes, put the alu tubes in and then fill the water galery ?

Thanks guys.

diabolical1 08-11-15 06:42 PM

i can tell you how i did mine, but that doesn't mean i did mine the right way.

i used Devcon Aluminum Putty (F). it's not clear and it's not a liquid. i'm guessing RB used Devcon, but some other kind of epoxy because it was their manual why i had even heard the name Devcon.

i bored the holes and inserted the sleeves, then i applied the epoxy. you'll want to clean the passages first. some people even go so far as scuffing the surface a bit.

whizzybang 08-12-15 10:57 AM

Thanks man. I feared the aluminium putty wouldn't go in the tight places and therefore would create coolant leaks inside or outside the housing.
How long can i play with the devcon once it is mixed, before everything goes too mich solid to use ?

Same question for the plastic steel putty for the plates.

TonyD89 08-12-15 04:53 PM

Has anyone tried aluminum soldering/brazing of the insert instead of epoxy? This stuff is good to over *700.

HTS-2000 - Second Generation Fluxless Brazing Rod | AluminumRepair.com


http://www.aluminumrepair.com/hts-20...FYI7gQodaKACrQ

diabolical1 08-12-15 06:45 PM


Originally Posted by whizzybang (Post 11953996)
Thanks man. I feared the aluminium putty wouldn't go in the tight places and therefore would create coolant leaks inside or outside the housing.
How long can i play with the devcon once it is mixed, before everything goes too mich solid to use ?

well, about all i can say is that it was leak proof. my engine never ran (never even got assembled aside from mockups for tests) so i'm totally clueless of how it will react after being heat-cycled. from what i remember (i did mine sometime in 2009) once i mixed it, it stayed relatively soft for quite a while. i took my time doing it because it was all new to me and i was a little nervous, so all told, i would guess maybe 60-90 minutes.


Same question for the plastic steel putty for the plates.
i have no idea on this. i've never epoxied a side housing before.

Kenku 08-13-15 08:01 AM

I did devcon in my rotor housings - it always leaked a little when it was hot. Something more liquid seems like it'd be better.

lastphaseofthis 08-13-15 05:23 PM

i welded mine.( alum to alum, uniquely) haven't run them yet maybe next year til i do. then i'll do a build thread.

j9fd3s 08-14-15 05:16 PM


Originally Posted by whizzybang (Post 11953996)
Same question for the plastic steel putty for the plates.

i did the devcon in the steel plates, it was actually pretty easy, and went really well. no worries about the stuff either, it is SOLID. i used the steel devcon, like RB says.

i haven't had to do a rotor housing yet, but the ones i have done use a threaded insert, and so i think it seals a little easier.

whizzybang 08-17-15 05:42 PM

Thank you everyne for the precious advice.

One more question : there are square holes on the side of the plates that connect to the exhaust port. Since i go PP, these holes won't be covered by the LIM anymore. Do i have to devcon them or what ? It seems i cannot leave them open.

j9fd3s 08-17-15 06:21 PM

it depends. some housing combinations will block them off. if not you can fill them.

whizzybang 08-21-15 05:10 PM

Just so you guys know : plates are done ! Well nearly, as 1lb of steel putty won't do 4 ports, but only 3.

http://nsm08.casimages.com/img/2015/...2013518391.jpg

http://nsm08.casimages.com/img/2015/...2013518390.jpg

http://nsm08.casimages.com/img/2015/...2013518388.jpg

http://nsm08.casimages.com/img/2015/...2013518387.jpg

http://nsm08.casimages.com/img/2015/...2013518386.jpg


PP's are on their way...

http://nsm08.casimages.com/img/2015/...2013518398.jpg

http://nsm08.casimages.com/img/2015/...2013518397.jpg

diabolical1 08-22-15 06:30 AM

look good. what kind of steel putty did you end up using?

whizzybang 08-22-15 06:32 AM

Devcon 10110 plastic steel putty.

j9fd3s 08-23-15 10:34 AM

i didn't fill the one i did all the way to the intake flange like you did, i dont think its really needed.

that being said yours look great!

almoststockrepu 08-23-15 11:22 AM

Did you cut the housings for practice and are planning on using another set?

whizzybang 08-23-15 04:29 PM

Building PP housings : made holes, need advice on epoxy
 
Thanks j9fd3s. I think it is not needed too but didn't know i would run out of product.

Yes this was a practice housing. The real ones are done now. I will use the aluminium putty in the next days. I hope i won't run into the same quantity problem.

whizzybang 08-28-15 08:00 AM

Hi all,

There is one question left : what about exhaust ports ? I use FD housings. Do i need to port the exhaust or will it kill the very last bit of torque i am expecting out of this engine ?
Or if i don't port, will i choke the engine ?

To be honest, i'm a dick with a Dremel tool, no steady hands at all so not comfortable with grinding the exhaust.

j9fd3s 08-31-15 01:04 PM

the good news is that the stock FD port is a good size.

the FD port opens at 71, and closes at 48 degrees. the race port opens at 73 degrees and closes at 55 or something, basically the race port is larger, but not by a lot. if you do cut the port bigger, make sure you put the bevel back

whizzybang 09-02-15 04:08 PM

Building PP housings : made holes, need advice on epoxy
 
Good news indeed. I'll just leave them be. It'll brap its ass off anyway

JZG 10-29-15 05:55 AM

I would probably move the entire intake port down a lot if you do it again ;)

whizzybang 10-29-15 06:35 AM

Why is that my friend ?

Rub20B 11-02-16 04:14 AM

to seal the water at the inserts I used araldite 2002 IIRC. seems to work good.

What intake closing angle you have with this ports? anything from 80-85° abdc is where you would be good for 9000 rpm.

whizzybang 11-04-16 04:23 AM

I have no idea. I drilled in the center of the boss made for coolant passages to the UIM on N/A's.


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