Engine questions

[robertnol91]

So I am looking at buying either a Tahoe or Yukon. My question is what are the different motors and what years or what should I look at when buying? I see a lot about obs, ls, vortec. Also the trans I read that all the ls motors will bolt to ls trannies?

 

[SunlitComet]

for 91-99 obs ,in which forum you posted in: the is 4 or 2 dr 4x2 or 4x4 units with 5.7l gas with 4l60e trannies and some 2 dr 4x4 with 6.5 l turbo diesel with 4l80e trannies. roughly speaking. the 1996-1999 mpfi vortec units have 50 more hp then earlier tbi's and are obd2 compliant.

 

[retorq]

The difference between the "LS trannies" and non LS are the input shaft size, convertor bolt pattern and the bell housing. The LS have a 300mm input shaft, use a 13 vane pump and have a removable 360 degree bell housing. Older transmissions used a 298mm shaft/convertor, 10 vane pumps (4L60es were, 700/4L60 non e used 7 or 10 vane setups) and had a "std" bellhousing that was not a full 360 bell housing as they call it.

New:

Old:

If you know what you are doing a TBI can run just as hard/fast as a Vortec.