I recently bought an ofna LX-1 nitro ready to run buggy. Even the manufacturers manual recommends upgrading the steering servo, other wise an excellent all around fun car. After browsing pages opon pages of them, I am still none the wiser. I know i want 90 oz or more, but how do i know it will fit and respond more quickly?

Servos size is standard and won't be a prob. It will fit.

Look at the spec on the servo, usually what you see quoted is servo torque at 2 voltages, 4.8 and 6v and a servo transit time. The torque is obvious, bigger numbers mean a stronger servo, transit time - smaller number means a servo that reacts faster to your input. Price generally increases as torque increases and transit time gets smaller.

duster is correct. another thing to keep in mind as a referance is .20 sec is usually rtr servo transit time. 90 oz in is absolute bare min for 1.8 off road. If you want great corner holding ability and positive steering go at least 135 oz in. I use a min 145 on all my 1/8 buggies and 190 on my truggy. A good servo Id recomend, besides any hitec would be a bluebird bms 660mg hs it has 190 oz in torque and a transit of .17 for like 23.00 at hk. I use these in my ofna and soon my sportwerks Or, a nice titanium gear digital hitec would be the best but set you back about 114.00.

I’m not familiar with the Ofna servo mounting, but in my experience 'standard' servos are not all the same size and configuration. There are differences, which may impact how well various models fit in various cars & how well the linkages line up, the offset of the mounting ears, depth and such. Possibly less of an issue with a 1/8 scale than smaller models, and especially 4wd offroad and touring cars that frequently require a low profile servo. Some 'standard' size models do not fit into some 2wd buggies & trucks, or at least don't without some modifications.

Also be aware the different brands use a variety of spline designs for the servo horn attachment, you may need a different horn for a particular servo.