I have picked up 2 na motors and was planning a rebuild for my car TT. Would love to rebuild the motor and then just pull my motor and do a quick change. I already have a set of ported tt manifolds and turbos sitting and waiting.
The cams would be differnt i think. They might still be good to put on a tt, i wonder if there is a hp benefit?
The TT engine runs lower compression ...than the NA. I expect the heads are what determines the compression so the NA heads are probably unsuitable for the TT.
I think you may be right There are different part numbers for the TT and NA pistons, but I can find only one listing for the cylinder head.
some answers... as fas as my investigating has revealed, TT and NA heads are the same. The auto TT's have slightly smaller CAMS, but the TT manual, NA manual and NA auto have the same heads. The pistons is different between TT and NA's and that is what determines the comp ratio. But as with evrything, please dont take my word for it, speak to a zed specialist who rebuilds zed engines for a living.
NA and TT heads are slightly different. The ports on the TT are slightly larger (according to the guys on TT.net) The volume of the compression chamber part of the head are the SAME. If you stick a TT head on a NA you will keep the CR of 10.5:1, and vice versa Auto TT cams are the only "soft" ones, Manual TT and all NA cams are the same. Valves are the same size, though the TT exhaust valves are Inconel. Valve springs are the same to the best of my knowledge. All this was in a thread from about 2 weeks ago when somone asked the same question. Try searching next time.
