I am about to put this on the 383 in my 97 Express van. At just over 11" off the china wall it will barely fit under the engine tunnel, but it will fit. Not overly concerned about low-speed torque loss because I am about to put a 6L90E in the van with a 4.03:1 1st gear and the current converter stalls 2,900 rpm in the 4L85E. I bet the 383 gains 50-60 hp with no other changes. It is currently strangled above 5,000 rpm with the L31 marine manifold and vortec air hat and pulls 2.5 in/hg intake vacuum at 5,500 rpm. For reference, the 383 made 412 hp and 430 tq at the wheels through a 4L85E in 2nd gear and a GM 10.5" corporate full floating 14 bolt spinning a massive clutch fan.

 

I have had this manifold for a while and finally getting around to installing it. Turned into a bit of a Medusa since I added a set of Proform LS coil relocation brackets that bolted right to the the 2 bolts holding the fuel rail on each side. The 4.5" to 4" coupler looks like it will have to be trimmed a bit so it will be a little less Snuffleupagas of an intake air duct when finished

 

Interesting. How tall is that above the carb pad?

 

Holley states 5.12". With the MSD throttle body sits a bit taller the way it is made where as my Fitech 92mm has a lower profile.

https://www.holley.com/products/ls_p...IaAgrlEALw_wcB

 

That manifold itself has been discontinued but I bought it during a Holley clearence sale. Along with the rails, elbow and MSD 103mm throttle body. The manifold ports are ~0.100" smaller than my head ports in each dimension but I am not going to modify the manifold in the event I want to run it on a stock vortec head dimension like the Etec170s I own at some point. Even stock port dimension the single plane will easily support the RPM I will spin the 383.

https://www.summitracing.com/parts/h...qO0Qj7P2Wndthz

 

How are you doing the coil on plug conversion?

it reminds me of the setup on my LT1 headed 305

 

Mine has been running with 24x and drive by wire for months now.