75mm TB (split from For Sale thread)

[ryan.hess]

On an intake everybody is going to see, you need both. That's why I love the LT5 intake... it's hot.

[timg]

mmm... 85mm MAF and 75mm TB goodness. Yours look better and are cheaper than mine was though.

I'm hoping to run this on my boosted LQ1, but I'm not sure if I'll have space. The engine bay is pretty packed already and even the inlet on the MAF is 3 3/4". These parts are absolutely HUGE.

FYI- a LOT of SR20DET guys use the 85mm TB from the 4.5L DOHC Nissan V8.

Tim

NOTE: I have no experience with these on any GM engine and have no idea how it will work. I just figured that if the boosted L67 guys use them successfully, I could too.

[gpse3400]

Well yeah.. let me give some factors you were working with though... Balding summer tires, a quasi LSD... and a linkage that was inncorrect for the angle of the cable which made it snap open even faster that it should've, I learned to deal with it, and enjoy it, made the engine feel a lot bigger than it was by far. Something has to be said getting the jump on every one at a stop light, perfect for traffic. Granted the response would've still have been there but with full tread tires and no lsd but at least you wouldn't light them up all the time, or youd be able to steer in the snow better. Later on I refitted the 4.3 linkage with that from a minivan 3400 linkage, I also installed the ported lower intake. Though I crashed the car that night....I was able to say the the TB was subdued. Definately not touchy. Overall the engine felt very blah. Tuning issue, hence the reason I was going to see you again. But then again maybe thats what is going to happen with my setup once I get into porting, Which then I'll need the 70mm tb to keep the bottom end alive.I guess what I'm trying to say is that as always to each is ones own liking and yeah my setup is one many...My engine has alot of cam, quite honestly I could use the extra thrust. The 3500 manifold and the 4.3 TB moved my vehicle pretty well. It might be inhailing more air earlier so how it that bad? Think about it from a track standpoint. One TB 65mm and another 70mm, both slammed down at the same speed, which intake manifold is going to atm first? I mean with a set of drag radials I could've easily got a 1.8 or a 1.9 with all the low end I had. You saw that hole shot against that LT1 Z28, granted my car left earlier, it took the Camaro a bit to catch. I've obtained 2.0's so I think I know what I'm talking about. Yeah it's touchy. But if you fix it up you can at least make it operate correctly. Food for uta booda.

lets pit experience against experience. 70mm on a 3400 makes it near undrivable on snow and is extremely touchy on dry ground as well.

[sharkey]

the size of the tb has very little to do with 60' times. i have a stock fiero 52mm tb and i managed a 2.0 60', granted, i leave off a 2 step and the tthrotle blade is wide open when im staged.

i still dont see the point in a gian tb. i mean, a stock 4.6l ford uses a 65mm tb, a 4.3l, 5.0l, and 5.7l all use a 75mm tb. we are talking about engines with more than a liter less displacment, why do they need a tb the same size as a v8??? they dont. all it does is make the throttle unnessesarely touchy.

[gpse3400]

Yeah I used to powerbrake, but now I just mash it. I ran a 245 45 16 tire so fanagling the throttle or power braking it didnt make a difference. As long as I did a nice long burnout. Get to tree the stage and go on the yellow. So thats how I'm looking at it. The time it takes for the engine to run up to the converter and move the car. You also must understand your ins a 25-2700 lb Cavalier and i'm in a 35-3600 lbs W car. Does'nt matter that you have a smaller TB on your engine as your engine is pretty big for your car as it is. But like I indicated once I went to the ported lower intake the response dropped. It really depends on your setup as to whether or not you need somthing like this. I felt it was nessesary. And it didnt cost me much at all nor did I hurt the motor when it was said and done. And its not that bad, You learn to drive the vehicle differently. Like any different car not all are alike. Some cars you gotta mash the gas harder, or the brakes, or turn the steering wheel more. Some people like cranking the wheel alot. I dont. Me being a native northeasterner, we like our equipment to operate with dispatch. So this is a plus in my book. I figure once I start throwing on all the ported hardware the response will quite possibly drop some more. I got a good comparison right here. Some people like using the poly dogbones to gain engine response, I like the larger TB. It all depends on setup and how you want your vehicle to operate.

[SappySE107]

TB size is also a function of plenum volume. The smaller the plenum the bigger the TB for max power. The 3500 plenum is larger than the 3400 and it has a larger TB. I would love to see anyone here do a test between their 70 or 75mm on a 3100/3400/3500 vs a 65. There is still the fact that the 3400 can't go bigger than 65 at the port opening and the 3500 would have to be cut up and welded to make it bigger than 65 down through the neck. Hell, it gets smaller diameter as well but not by as much as you would going 70+ on either intake.

[mike b]

75mm tb

will a 75mm tb work on ly7 v6 3.6? And work with a Haltech e6x?

[Identity Crisis]

I will do the test with the 75mm TB and a stock one from a 3400. I need to purchase the adapter from sappy though.

[mike b]

RYAN do you still have the 75mm tb for sale and do they have tps on them?