Irons and intake manifolds!
Irons and intake manifolds!
I'm at the start of getting together parts to build a new motor. Are all the intake manifolds compatible with all the irons? For example, can i have REW irons and BT intake? Or RE irons and REW intake...etc? If not is it because the bolt patterns are different between the various years?
The short answer is no.
Do some searches and research, because that question has already been answered countless times.
The REW lower only fits an REW iron set. The 13BT lower only fits S4 and S5 irons. The BT lower can be ported to fit 13B NA housings from 86-91.
The RE lower can be mated to an REW with modifications, just do a search for it.
The REW upper intake can be adapted to the 13BT lower with a spacer, or by welding the REW upper between the primary runners and port matching the manifolds.
It would help if you stated what engine/car you are trying to build. Xcessive manufacturing makes a great lower manifole for the REW and Elite Rotary has a full intake system for the REW, Cosmo, and 13BT. Again, do some more searching.
Do some searches and research, because that question has already been answered countless times.
The REW lower only fits an REW iron set. The 13BT lower only fits S4 and S5 irons. The BT lower can be ported to fit 13B NA housings from 86-91.
The RE lower can be mated to an REW with modifications, just do a search for it.
The REW upper intake can be adapted to the 13BT lower with a spacer, or by welding the REW upper between the primary runners and port matching the manifolds.
It would help if you stated what engine/car you are trying to build. Xcessive manufacturing makes a great lower manifole for the REW and Elite Rotary has a full intake system for the REW, Cosmo, and 13BT. Again, do some more searching.
If you're "at the start", just get the proper parts from the proper model and be done with it. Frankensteining just doesn't make sense most of the time. If you're looking at used...and you will be in some instances, download a copy of the Factory Service Manual for spec guidelines as to what's usable. And note that rotors carry weight designations in the form of letters.
rotorhole
Joined: May 2017
Posts: 680
Likes: 70
From: retired rotorist
REW and BT intake ports and bolt patterns are drastically different, you're barking up the wrong tree if you think they can be interchanged in any way.
most notable is the reason it would require an adapter, in a location where the turbo lives and will not allow such a thing. the 13B-T intake manifold is also inferior to the 13B-REW. most FC guys trying to get the most from their car adapt the REW intake to the BT lower intake manifold, going any further just causes massive headaches for an actual negative outcome, since the transition at the upper to lower is the easiest to form. the BT lower can't be ported to match the REW without massive work and would have some strange curves.
most notable is the reason it would require an adapter, in a location where the turbo lives and will not allow such a thing. the 13B-T intake manifold is also inferior to the 13B-REW. most FC guys trying to get the most from their car adapt the REW intake to the BT lower intake manifold, going any further just causes massive headaches for an actual negative outcome, since the transition at the upper to lower is the easiest to form. the BT lower can't be ported to match the REW without massive work and would have some strange curves.
Last edited by insightful; Jul 22, 2017 at 11:22 AM.