I paid $700Us for my Marine intake that came with: upper, lower, injectors,(28#) IAT, MAP, fuel rails(stainless), fuel pressure regulator, marine t-body.
It came with everything that is on the intake in this picture
http://store.summitracing.com/defaul...h.asp&x=27&y=5
This intake was designed for both 350 and 383 cube engines. Its intake ports are slightly larger than the stock L31 truck intake, I personally measured them. The intake runners are only 8" long.
The Marine Intake is over $3000US if you buy it new.
http://www.mercruiserparts.com/Show_...+and+Fuel+Rail
Here is the Marine Intake right next to an L31 truck intake.(scroll down, 2nd last picture) thereare also some excellent comparitive poppet spider and multec spider pics.
The Marine Intake looks very similar to the stock truck intake, but I tell you that there perfromance is quite difference. Mytruck has never pulled as hard as it does form 3200 to 5800 rpm as it does with this intake.
With the vertical facing Marine Intake the air is allready heading in a downward fashion and spirals around in the intake then heads down into the intake port runners. With the Ramjet, the airflow is travelling in a hrizontal direction thru it horizontal t-body, then it has to make a 90 degree turn down to enter the intake ports.
The Ramjet does have shorter intake runners though.
P/N 12489371 350 RamJet Manifold is teh pn for the bare intake alone. This costs $800CAN.
The 12498032 is the Ramjet fuel injection kit, comes with, coil, intake, distributer, knock sensor,fuel rails, t-body,injectors, map sensor and FPR.
The stuff that would be needed for the truck swap totals $2230CAN. This price doesnt include ALL the above listed stuff, just the stuff that is need for a truck app.
In my opinion, the Ramjet, MArine swap is very usefull for those who will be using a super charger turbo or dry nitrous system or larger stroker engines swap is to ube able to use larger replaceable fuel injectoirs and to get away from the stock 19 lb/hr poppet and MPFI spiders.
Simply swapping on these intakes for power gains from a stock L31 is a very expensive dollar per hp proposition.
The folks involved in out MArineIntake project will have some dyno numbers and track times soon. The supercharged guys are reporting nice SOTP gains., and I am getting good results onlystock longblock NA setup. There are now only 3 of us with teh MArine Intakes installed, mine on a Vortec 350 and 2 of them on Whippled 350's. The guy with a Vortec 383 took his off as he is selling the truck
Finding a used MArine or Ramjet intake is the key tokeeping costs down for both projects. I completed my marine swap for under $1000US including PCM tuning. You need to change the injector fuel flow tables to correct for whatever sized injectors you are using. As long as the injectors are high impedance, the PCM will drive them.
the guy who is selling the MArine intake kits is selling them for $750US. All you need to buy to install it is fuel feed lines and intake gaskets. This guy even machines in the front hole and thread to allow the stock Vortec cooling hoses to be used. He is a very straight up guy. he even sends you colour coded wires that matches teh stock GM injectors harness, weatherpack injectors connectors, a wiring diagram for thevortec injection harness, t-body gaskets, various fittings.
He has just received 2 or 3 more marine intakes. If anyone wnats 1 or more info directly from him. please PM me and I will put you in touch with him through the proper channels. I believehe has sold 10 or 12 of them.
the marine intake is much better than the stock L31 setup, the plenum volume is increased and flow improved simply from removing all of the L31 Vortec fuel popets, feed lines and fule pressure regulator from the plenum. the inside floor of the plenum is flat compare dto the horribly contoured floor of the L31 truck piece.
if you need an adjustable fuel pressure regulator, an AFPR from an LS1 Vette with the return style fuel system will work, but noone so far has used 1, or needed 1.
98bagsilverado has a killer setup with his Ramjet intake on an L31 engine, finally the L31 can post some good numbers.
peace
Pauly