It's a waste of time unless you already have a great deal of mod's and you are pushing some serious horsepower. You won't feel it otherwise. If you have only done intake, from what I have heard (I have not done the swap), it isn't going to do anything worthwhile for you.
What you are doing, from my understanding, is you are allowing more gas to flow through because you have a wider throttle body then that of the 300zx. Wider throttle body, more gas gets through when your foot is on the pedal. The 240sx is close to that of the 300zx but it is wider.
Are you joking? Have you looked at where your TB is and how a car works? It also won't help becuase the rest of the intake pipes are a smaller diameter because they were made to match up with the stock TB. Kind of like having a 3" Cat with a 2" exhuast system. It's really doing nothing.
Well if you think about it a 240sx motor is a 2.4 Liter so why wouldnt it help on a 3 liter, me myself I gained a couple tenths in the 1/4 and went from 80mph to 82mph when my car was non-turbo so not unless youve tried this you really cant believe what you read.
Well I remember about 2-3 years ago there was a guy on zcar.com that did a dyno and track test on both the non turbo and turbo. Both showed no respectable gains. By that I mean 1 or less hp and less than .1 sec in the 1/4 mile. Remember that just becuase one week you run a certain time at the track doesn't mean that the next week will be the same. In order to really nail down what your car runs in the 1/4 mile several track tests at different times need to be done to see what your best consistent time is. Your best time must be repeated several times and then can you say that the addition of a mod actually helped drop it. For instance your first time or second time to the track you run a 16.5 with a stock non turbo 300zx. Then you add the 60mm tb and go back a couple months later and run a 16.3. Does that mean the 60mm tb acutally made your faster? NO!! Your driving could have been better, track prep could be better, weather, etc. Back to back tests like the one done by that guy on zcar.com is really the best way to test a mod. The only other way is to know what your car runs consistently. For example my 280z has run the exact same times at the track the last 9 times I've gone. At this point any addition of a mod and drop of time could be used as a measurement of how much that mod helped. However it took me serveral times in the beginning to actually be consistent with my car. If you knew the specs on the VG engine you would know that the head and intake manifold are way more constricted than the throttle body. So having a larger tb wouldn't allow any more air to flow into the engine. Domdogg123 gave a good example; "Kind of like having a 3" Cat with a 2" exhuast system. It's really doing nothing." Whats the point of opening up the tb if the rest of the breathing system in smaller. Basicly if there was a race between a stock 300zx vs one with a 60mm tb with everything else being equal I believe the race would be a tie as the larger tb would give no advantage.
Yeah - 280z/300zx said it best. I was interested to here some actual facts.
"If you knew the specs on the VG engine you would know that the head and intake manifold are way more constricted than the throttle body. So having a larger tb wouldn't allow any more air to flow into the engine."
Not just heresy for once!
85 n/a - K&N Air filter w/resonator removed - Maxima Alternator swap
wow folks shows that no one really knows enough about this mod lol..the stanza and 240sx TB are the same both are a 60mm TB so ya no difference either one will work the 300zx is 55mm so you have to grind away the plenum to get it to fit z31.com gives better details but thats the just of it
What??? Most of the people that responded to this have done the mod or researched it enough. I personaly know enough about it not to waste my time and money on it. It's common knowledge that the stanza and 240sx tb are similar and both 60mm. Also I believe you are wrong about the 55m stock unit. I'm pretty sure it's either 52mm or 54mm. Grind away the plenum all you want but unless you extrude hone it like Engloid it won't matter.