TD04H GReddy (T25) on Ebay Cast T3 Manifold
 

Alright guys, firstly:
- Mk1 1.6 (Eunos)
- Bastardised GReddy kit (TD04H-15G)
- Std GReddy manifold and D/P
- RX7 FMIC, unknown pipework.
- PAS and A/C.

The turbo manifold is, unsurprisingly, cracked and three (!) of the Turbo bolts have sheared in the turbo flange.

Ok, so I was given an ebay cast T3 manifold (TacoTaco et al) and a 2" T3 to T25 adaptor. The Cast manifold flange sits at ~45deg from horizontal and about 2" further towards the front of the car than the GReddy, and the flange adaptor would put it ~2" out from the Flange.

Has anyone done anything similar? and had any clearance issues with the bonnet?

http://www.pbase.com/image/130574024.jpg

I'll probably have to clock the turbo slightly. FMIC pipework and downpipe will also need adapting, but actually as it's further forward this will give me a lot more space to play with on the D/P side.

Whilst I'm aware it's a bodge, it's what i've got, so there's little harm in playing with it. The other option of course is just repair the GReddy and be done with it, but thought this would give me more space for Downpipe design and be a 'slightly' better manifold.

Cheers,

Dave

btw, my intro thread is over at: https://www.miataturbo.net/meet-greet-40/n00b-reading-uk-53729/

Are you not able to close the hood to check the clearance?

I would think you will have more problems with the downpipe and getting one to work with that rather than the turbo sitting too high for the hood.

I use the same manifold but without a 2" adapter (I use a t3 footprint turbo) and I have plenty of room for the hood.

I would imagine 2" on that turbo would be ok, but there's only one way to find out which is actually try it, as I doubt many here have done that before.

Yeah obviously the only way to properly find out is fit it all up. It was just a shot in the dark in case any HAD done it, or there's some retarded issue that would come out of it that i've missed.

For a number of reasons the MX is going into a local garage to do the manifold swop. The main being I'm also working on my 16V Mk1 Golf (Rabbit) at the moment, plus I don't have access to my welder where I'm living at the moment.

Am trying to be as prepared as I can. Removing/refitting shouldn't be a long job for them as i've oiled/loosened and refitted most of the nuts/bolts inc downpipe. They can then fit it fairly simply and do the modifications to the D/P or, if reasonable cost, knock up a custom 2.5" bore one instead as I gather the GReddy D/P is a pile of wank anyway.

Dave

Ok, GReddy manifold is off and fubar, at least 3 main cracks with one going all the way though main flange.

Have done a dry fit of the Ebay special with adaptor and Turbo and it looks good so far, it sits lower than I expected. Garage to cut'n'shut the GReddy downpipe tomorrow.

Gotta ask, did you have the relief cuts in the greddy manifold?

Throw up some pictures of the entire process if you can. Those manifolds are starting to become very popular around here and seeing what it looks like with a adapter might be useful to some.

Hope you get your car back and running soon.

Nope, the GReddy didn't have the relief cuts made. To be fair to the seller he did tell me the manifold was cracked when I bought the car.

I haven't got any mid process pictures but it shouldn't be much effort to whip off the intake piping and get some images of the setup. Assuming it works, lol.

On the plus side, aside from crap from the Head breather, the Turbo is looking ok given it's likely age. Not much float etc.

Should I be adding relief cuts to the Ebay manifold?

I may end up pulling it all off at some point anyway, the port matching between the adaptor and manifold is rubbish. Focus is getting it going and reliable first, full up service in order next.

I've changed the Title to make it more relevant.

The MX is back in the drive now. The Turbo clears the bonnet fine, a few mods were required to my FMIC pipework and the Downpipe has been modified.

IMO the downpipe routing is a bit better, a few more inches clearance from the firewall allows it to go straight down, less bends required.

Pictures will follow this weekend sometime...I'm off into town for a Christmas lash, a beer or two/many with work mates :)

I put relief cuts in my taco ebay manifold (same one you have) and it hasn't cracked yet.

I also put relief cuts in my old greddy manifold and it never cracked either.

It's up to you but if it were me I would.

Fair play, cheers.

Goddamn it's cold over here at the moment, haven't touched the car since I got it back, lol.

I've barely touched the Roadster over the last month as I was avoiding sorting out a nasty noise from the front Off-side. Yesterday I bit the bullet and changed the hub/bearing and gave it a vague clean, so it's back on the road and I've have taken some pictures as requested.

And yes...I do know the T3 gasket has gone already...from my scouting on here it seems that it may be better to not run a gasket,so I'll pull the turbo and try that. At the same time I'll do the relief cuts between runners.

Anyway here's the pictures. It's not pretty, but it does the job for relatively little outlay. Only hassle really is modifying the downpipe, and PAS line had to be rotated and it's bracket cut down.

The (Messy!) Bay:
http://www.pbase.com/dgawen/image/131860231.jpg


New layout:
http://www.pbase.com/dgawen/image/131860217.jpg

http://www.pbase.com/dgawen/image/131860227.jpg


It's up a bit further but clear bonnet no problem:
http://www.pbase.com/dgawen/image/131860226.jpg


Inlet clocked upwards slightly and actuator shuffled round:
http://www.pbase.com/dgawen/image/131860228.jpg


T3-T25 adaptor stacked onto Ebay Cast T3 manifold, this also shows cut down PAS line bracket which I need to tidy up.
http://www.pbase.com/dgawen/image/131860219.jpg


Damn gasket!
http://www.pbase.com/dgawen/image/131860221.jpg

http://www.pbase.com/dgawen/image/131860230.jpg


The cast manifold flange is angled downwards approx 45deg compared to the horizontal flange of the GReddy Manifold, it's also located a few Inches further forwards (towards the front of the car). As a result the outlet flange has been rotated and moved forwards:
http://www.pbase.com/dgawen/image/131860223.jpg


The Turbo relocation means more space for the downpipe routing, less bends required. A total of approx 90deg worth of bend sections removed from the GReddy downpipe and a straight section welded in. Hopefully this will also make things easier when/if I get round to making a larger bore downpipe.
http://www.pbase.com/dgawen/image/131860224.jpg


Centre exit exhaust with ickle silencer. It's probably too small a bore as well but it will stay for the moment:
http://www.pbase.com/dgawen/image/131860235.jpg

And for good measure a few random images of the car:

http://www.pbase.com/dgawen/image/131860208.jpg

http://www.pbase.com/dgawen/image/131860232.jpg

http://www.pbase.com/dgawen/image/131860236.jpg