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kc0000
08-22-2002, 09:13 PM
I've decided..... After many weeks of research and agony over bidding on motors on EBay.... it is time to upgrade my motor.

Measuring the engine bay this weekend, if clearances allow I'll order the new motor project on Monday!

KC

The recipe is simple; one part attitude, one part driving perfection, one part leading factory technology, and five hundred and two parts hungry rat motor. Ram Jet 502, you either have one or you want one !

When the idea of an all new big-block fuel injection system first came up, we all thought it was a good one. When it was proposed that it be integrated with our 502 crate engine, we thought somebody clearly lost their mind. Who could possibly need the awesome, flat, broad torque curve only available with a long runner dry manifold ? And who would want the neck-snapping throttle response of MEFI 3 controlled port fuel injectors ? And what would be the need for aggressive tunnel ram styling ? But then we remembered we're not building 100 mile per gallon, 0 to 60 in a week, econo-scooters. We're in the hot rod business ! So we called together engine management system experts from GM Powertrain, our own GMPP engineers, and fuel injected race engine builder and GMPP Pro Mod racer Harold Martin. After some great discussions, a little debate, a lot of late nights and 50 gallons of coffee we had an intake manifold design like no other. By leveraging leading fuel management technology, numerous production developed components, the industry standard MEFI 3 controller and the great Ram Jet name from the 1950's, the Ram Jet 502 is a reality.

The new undisputed heavy weight champion, the Ram Jet 502, makes 510 horsepower at 5500 RPM and 550 Ft/Lbs of torque at 4500 RPM. But the real story is the torque curve, the Ram Jet 502 makes more torque throughout its operating range. This is possible because Ram Jet has a larger plenum and runners than would ever be possible in a carbureted application. This means greater intake efficiency and greater torque without sacrificing driveability. The Ram Jet manifold is so efficient that we're able to make all of this horsepower and torque with a production L98 throttle body assembly, you know, the one that Firebird and Camaro owners always replace when trying to make more power in their 350ci engines. It's all about airflow quality, velocity, and fuel and spark management. You'll just have to drive one to appreciate it. If the one-second cold starts, no stalling, instant throttle response, and the solid pull from idle to red line don't convince you that a Ram Jet 502 is for you, then maybe we could interest you in a 100 mile per gallon, 0 to 60 in a week econo-scooter !

The Ram Jet 502 is not intended for marine use, and should only be used in 1973 and earlier pre-emissions street vehicles or any year off road vehicles.

Technical Notes: Do not use bolt sealer on the cylinder head bolts, the holes are blind tapped. The long block kit includes partial engine, cylinder heads, valve covers, valvetrain, and fasteners and gaskets for the parts included. The complete engine kit includes the long block kit plus intake manifold, carburetor, distributor, water pump, spark plugs, spark plug wires with looms and additional fasteners and gaskets.



Ram Jet 502 Technical Information

Horsepower .......................................510 @ 5500 RPM

Torque .................................................5 50 Ft Lbs @ 4500 RPM

Maximum Recommended RPM .....5800

Compression Ratio ............................9.6:1

Block .................................................. ..10237292 - Cast Iron 4-Bolt Mains

Crankshaft ..........................................10183723 - Forged Steel

Connecting Rods ..............................10198922 - Forged Steel

Shot Peened, 7/16" Bolts

Pistons .................................................. 12533507 - Forged Aluminum

Piston Rings ........................................12524293

Camshaft .............................................12336 543 - Hydraulic Roller

Lift: .527" Intake, .544" Exhaust

Camshaft Duration @ .050" .............224° Intake, 234° Exhaust

Timing Chain .......................................3891519 - Single Roller

Cylinder Heads ...................................12363390 - Aluminum Oval Port

110cc Combustion Chambers

Intake Valves ......................................12366987 - 2.25" Stainless Steel

Exhaust Valves ...................................12366988 - 1.88" Stainless Steel

Valve Springs ......................................12462970

Rocker Arms ........................................12523976 - 1.7:1 Ratio

Distributor....................................... ...... HEI

Valve Lash ............................................Zero

Fuel .................................................. ......92 Octane

Spark Plug ........................................... 25164642 Rapid Fire

Ignition Timing ....................................8° @ 800 RPM

36° Total @ 5000 RPM



Tech Tip
"Oil Filter & Oil Cooler Bypass Valves"

Excerpt from Speed Reading, written by Wade Hajek of GM Performance Parts

Gen V and Gen VI big-block crate engines come with two oil pressure bypass valves installed in the engine blocks. Both of these valves are rated at 11 psi pressure differential. One valve is for the oil filter and the other is for the production oil cooler. If you install an aftermarket oil cooler or remote oil filter that attaches to the oil filter pad on the engine block, you should be aware that you need to change the oil filter bypass valve in the engine block. The aftermarket oil lines add resistance which will cause the bypass valve to bypass the aftermarket oil cooler and/or oil filter all the time. Obviously, if the cooler and filter are bypassed the oil will be dirty and hot. Your engine could run hotter and could be damaged by dirt in the oil. If you choose to use an aftermarket cooler or remote oil filter that attaches to the pad, you should change the bypass valve to one with a higher differential pressure rating. A good choice would be GM# 25161284 which is rated at 30 psi. Remove the valve that is closest to the crankshaft and replace it with the new valve. Press the new valve into the engine block and stake it in three places. You should note that the bypass valves don't need to be changed if you use a production oil cooler which uses the production holes in the engine block and you don't use a remote oil filter. Also, if you use an adapter that just angles the filter for clearance you don't need to change the bypass valves.

BADFISH II
08-23-2002, 12:14 AM
WTF?http://www.lasvegashotboats.com/iB_html/non-cgi/emoticons/confused.gif?http://www.lasvegashotboats.com/iB_html/non-cgi/emoticons/confused.gif?? whatever he said, wish I had a clue http://www.lasvegashotboats.com/iB_html/non-cgi/emoticons/confused.gif

THOR
08-23-2002, 06:23 AM
KC,
If I remember correctly, you have the 7.4 right?

If so, my buddy put a procharger on his, and it is running at 3 lbs of boost making roughly 450 HP. In your boat (23' right?) you should be able to run a 25-28P prop spinning around 4700 rpm. That equates to about 75 mph. SWEEEEEEEEEEEEEEEEEEEEEEEEEET.

For roughly 5-6K installed!!!! Ever thought of that?

Essex502
08-23-2002, 07:17 AM
KC - sweet motor! Go for it!

kc0000
08-23-2002, 07:24 AM
Essex502....
How large of a boat are you looking for?
KC

kevnmcd
08-23-2002, 10:19 AM
I am soooooooo damn jealous! Â*I want one, too! Â* http://www.lasvegashotboats.com/iB_html/non-cgi/emoticons/sad.gif

KC - Did you see the part about 92 octane? Oh well, I guess if you can afford and motor like that you can afford 91 octane and octane boost! Good luck! Can't wait to hear about the project, take lots of pictures to share. http://www.lasvegashotboats.com/iB_html/non-cgi/emoticons/smile.gif

kc0000
08-23-2002, 11:39 AM
I did see the 92 octane... I am hoping that the hot dry air of Havasu gives me an edge so that it remains at 92 octane, or less... Another option, if I decide to take down the heads to upgrade the valves, at that time I might "soften" the combustion chamber of the head based upon some reading I have done, that would lower the compression a bit and improve the flow and burn of the chamber.....

project, project, project..... http://www.lasvegashotboats.com/iB_html/non-cgi/emoticons/cool.gif

Essex502
08-28-2002, 07:17 AM
kc - see the offer below on RRX:HP500 (http://www.riverracerx.com/cgi-bin/mb/ikonboard.cgi?act=ST;f=6;t=44;hl=new)

dave
08-28-2002, 11:36 AM
That sounds like a monster!

kc0000
08-28-2002, 03:20 PM
SHOOT ! That monster will not fit inside my engine bay without cutting a scoop into the sun deck... I am liking the sleepy look of my ride and don't want to spoil it.

So last night I picked up a 454 MAG MPI 385hp on EBay, a long block with only 20 hours on the motor, less the intake and the MPI. Once delivered it is getting a Whipple top mounted EFI system and I will swap all of my accessories from my 310hp to the 385hp - after that it should produce about 610hp.

might need a bigger prop....
KC

duckbutter
08-28-2002, 03:22 PM
Sounds pretty sweet http://www.lasvegashotboats.com/iB_html/non-cgi/emoticons/biggrin.gif