Nevermind

 

please delete thread

 

Alright
I am just looking for opinions before I dyno
I have stock throttle body and injectors

Will I need to upgrade the injectors in the stock TB when I dyno?

Would I benefit from the 58 mm Throttle body?

I am just looking for torque not a drag racer

Thanks

 

guess it all depends what size the intakes on your heads are . usually over 100 hp are the larger injectors. I think the 58mm is 1.7 inches but Im not positive. so if u have the same size intake into the heads the transiton fit would be very smooth., if you have the larger intake on the heads with the small stock intake the velocity will slow down a bit as it expands into the larger opening. guess u need to find out who ever did your heads and what opening size they have

 

My opinion is you should spend a little time looking at dyno charts to see the effect on the curve, ideally compare two builds that are the same except for the throttle body then you can get an idea of how it will affect the torque curve. The 777 is a pretty popular cam and there should be plenty of dyno charts out there, if I remember right there are quite a few on FM's website, or you could pick up the phone and call them since you are using their parts they should have a pretty good idea of what it will do. The internet myth that a bigger TB always reduces low end torque isn't true, just did an M8 cam change then added a TB it picked up all the way across the curve. Key is the right sized TB too small and it can choke it on the low end too too big and it will not flow well.

 

Probably a conversation with FM would be the best.
We, however, have dedicated recorded flow numbers on our Stage IV Heads, and Stage II CVO Wet Heads, pulling thru our 50mm, S/E 58, and S&S 66mm t/bodys, as tested on our Superflow 600 bench, at .100" thru .700" of valve lift.
Scott

 

I talked to FM and Zippers and both are in agreement that stock inj and TB are fine until you get up around 120/125 hp, and have ported heads, then the 58mm and hi-flow inj will benefit. I am going to do a stage 4 soon, and I sold off the 58 mm and hi-flows to get some of my money back. I got a package deal from someone and kept the cams/pistons/heads to install on my 103.

 

old thread

I believe that I made a mistake by not going to a 58mm TB
especially with the 777 cam which is awesome but not a lower RPM cam by any means
I did the bigger fuel injectors and all the other good stuff
I left some on the table

All that money and time just do it right i guess

Everyone Have a great Labor Day weekend

 

Why not at lower rpm? What compression are you running?