Do I Need A 70mm Tb

[skiwesser11]

At what horsepower level do I need to swap from 65 mm to 70 mm? It dynoed 300 to the wheels with a 65 mm on a 306
H/C/I combo with long tubes and a 73mm C&L.
I've been told to go with 77 mm pro m and a 70mm throttle body but I do not want to sacrifice throttle response or drivability.
I've been told I would make significantly more power with no sacrifice, agree??
Of course I will have it retuned, I may go with bigger cam in which case I will most probably go with the larger TB and air meter.

 

[2000xp8]

Not worth the trouble. There is coupe of hp there, literally, like two.
Since i know you are already working on the pro m meter, next i'd think about a better intake if you are really using a typhoon.

If you were to get a really good intake like an RPM II, if anything jump straight to a 75, regardless the tb on a 306 isn't going to make a huge difference.

 

[skiwesser11]

Not worth the trouble. There is coupe of hp there, literally, like two.
Since i know you are already working on the pro m meter, next i'd think about a better intake if you are really using a typhoon.

If you were to get a really good intake like an RPM II, if anything jump straight to a 75, regardless the tb on a 306 isn't going to make a huge difference.

Is the typhoon really that bad? What intake would be best suited to a 90% street car? I'm still hung up on swapping cam but the tfs #1 is great on the street and it pulls hard.
Are you talking bout a pro m 75?
How about the BBK 76mm?
I need more somthing

 

[2000xp8]

Is the typhoon really that bad? What intake would be best suited to a 90% street car? I'm still hung up on swapping cam but the tfs #1 is great on the street and it pulls hard.
Are you talking bout a pro m 75?
How about the BBK 76mm?
I need more somthing

I was speaking of a 75mm tb. Far from a requirement though.
IMO, yes the typhoon is that bad, it's a knock off and not a good one. It's crude to compared to other ones out there.


I don't think bbk makes a 76 anything, but if they did, i wouldn't buy it anyway.

Me personally, i wouldn't be happy with any afr setup that made less than 330rwhp.

Custom cam, better intake, a real mass air meter should easily put you at that number.

 

[mikestang63]

typhoon intakes are knock offs of edelbrocks and are known to have lots of casting flash and infererior quality control on tolerances. If you replace your existing TB, save up and get an Accufab.

 

[skiwesser11]

I'm sure it's inferior seeing as it's a Chinese knock off but it's port matched and looks ok so I used it cause my buddy had it. 75mm is way too big on t body for a 306 isn't it?
So is it the electronics that make the pro m better than the C&L? The difference in flow between 73-76mm couldn't be that much, besides either will flow more air than the throttle body, correct?

 

[2000xp8]

For the most part on a 306, anywhere from a 65-75 TB is fine depending on your setup.
Yes it's the electronics that do the work. The C&L sampling tube setup is just inaccurate.

If you like the intake, keep it. But it appears by your posts that you are interested in more power.
But you really aren't going too much more coupling great heads with a bunch of generic supporting parts like that intake.

 

[skiwesser11]

For the most part on a 306, anywhere from a 65-75 TB is fine depending on your setup.
Yes it's the electronics that do the work. The C&L sampling tube setup is just inaccurate.

If you like the intake, keep it. But it appears by your posts that you are interested in more power.
But you really aren't going too much more coupling great heads with a bunch of generic supporting parts like that intake.

You got me there and I agree, so which intake? while I want to make the most of the head I do want to maintain street ability. So there's where I wonder if more cam would do more harm than good. Maybe I will shell out the $ for a custom cam, I dunno, if I'm gonna "re"do it, do it right I guess.

 

[2000xp8]

If it were me? I'd use an rpmII intake. Little bit big, but i've seen it perform great on 302's and 347's with afr's. I'm willing to give up a little down low for alot up top. Just don't go nuts with the cam and you will be fine.

 

[skiwesser11]

If it were me? I'd use an rpmII intake. Little bit big, but i've seen it perform great on 302's and 347's with afr's. I'm willing to give up a little down low for alot up top. Just don't go nuts with the cam and you will be fine.

Ok thanks that's what I was wondering, maybe a shorter runner intake, I guess I'll start with pricing a custom cam and perhaps pick intake based on cam and advise from cam co. again most of what I know is all theory so I figured prob best to stay away from short runner intake as it's mostly street driven and I don't wanna lose too much low-mid range torque/hp.
I agree that 300 rwhp isn't enough with afr's, and they are 58cc combustion chambers: AFR part #1402