SBC oil pan questions
 

I am putting together a 383 for my 94 Sylvan 209 Barritz to replace the tired 305. The block is a 1970's two piece rear main seal with drivers (port) side dipstick through the block. I have an old deep sump circle track pan I was planning to use with baffling. I have plenty of depth to fit this pan in the bilge. I plan to add a milodon louvered windage tray also. Exhaust will be OEM mercruiser cast manifolds. My take out 305 is a one piece rear main seal engine so oil pan, oil pump pickup, dipstick set up etc. will not transfer.

Question: Should I use header flanges and gaskets to space out the manifolds and use the factory GM style dipstick hole and dipstick? Or weld a pipe on the oil pan and make an entirely new dipstick and plug the engine tube port? Or are there off the shelf components to use a Mercruiser style pumpable dipstick tube with this style engine? I've found several old threads but most come up with obsolete Mercruiser part numbers and never really state a solution. Using a GM style dipstick will still require plumbing hose or tubing to the drain plug for oil change access, but hydraulic hose and fittings would accomplish this part if need be. What have others done in this situation?

I have new Dart Small blocks with which had similar problems. My solution was to fit a Tee fitting to the oil pan drain on the side with an elbow at the end to which I fitted an aftermarket dip stick, The centre of the Tee was fitted with a length of Hydraulic hose with a screw plug end as a blank so that I can fit an oil extraction pump at any time remotely. It works very well and is simple.
I also turned blanking plugs to fit into the original Dart dip stick holes in the block.
Kalaazar

K.I.S.S., dont use the manifold spacers. It just adds unneeded complexity to your system. Like Kalaazar said, put a T in the pan, one side for the oil drain hose and the other for where the dipstick goes in.

I modified the after market dip stick with a tube bender. Gentle bends just to get it past the manifold.

Do you remember what you started with for an aftermarket dipstick assy.? This is what I want to try and then fab. a separate hose assy. to the pan plug just for oil changes.

If bending the tube doesn't help, maybe look into one of the Lockar flexible set ups:
http://www.summitracing.com/search/b...-Included/Yes/

I bought my dipsticks from Summit Racing, both simple and very flexible.
Yes a separate hose just for oil changes because you can make it as long as you want for easy access and it provides a larger bore and can be connected to at any time without trying to find the drain plug down in the bilge.
I have a twin installation which is very tight to the point that I have had to fit AFR sensors rather that try to remove a hot spark plug to check the colour.
So being able to reach the lowest part of the sump from the cockpit is great.
Kalaazar

It was just a standard chrome Trans Dapt dip stick. For the remote oil drain hose. I measured the thread on the oil pan mine was 1/2-20. I ordered this kit of Amazon http://www.amazon.com/gp/product/B00...ilpage_o01_s00

This is the same one that is on my Donzi. It fits through the bilge drain hole. Another good option.

Jeff

Awesome, thank you everyone for the help.

My build is a little different but I'll throw it in there too, I used a Canton road race oil pan on my 383 build and the dipstick is starboard side. I reused the original 260 dipstick, but my problem was the tube wouldn't go through the windage tray in the pan and would kick it to the side. So I had to cut the length which rendered the evacuating capabilities useless, not a game breaker for me. Then when I was checking oil in the pan VS. the dipstick reading it wasn't reading right so I had to cut off the threads at the top of the tube, there again it wouldn't evacuate anyways so no big deal.
Bottom line I was able to massage the tube and it fit the outside of the SM exhaust and still used the existing mount on the tube and it looks factory, see pic below, sorry it doesn't show very well.

CC230,

Where did you find those anodized pulleys? They look sweet! What did you go with for cam, carb, intake combo on your 383 build?

most of the oil changers include the small tube that will go down the tube to bottom of pan and work fine for oil changes

94Sylvan, the pulleys are painted same color as the block, they just look anodized. As far as the build, I used Vortec heads ported, polished and flowed, the stud bosses were cut down and I used 7/16 screw in studs with beehive springs and Scorpion Endurance rocker arms.
Once they were done we CC'd the chambers down to 60cc per Bob Madera. Cut the deck and used Cometic gaskets to get 9.4:1 compression and he designed the cam from there. Used a RPM Air gap intake and still need to get a good carb among other things. I fired it up on the cradle stand, sounds great, very stout and idles at 700 rpm. Sad part is I've been too busy to finish the boat!
ezstriper , that's what I used in the past and had in the back of my mind also, thanks.

It may be a good idea to paint your oil pan. I've had corrosion form on the zinc wash. You'll notice that the Canton marine pan is painted.

Jeff

The canton pan had the zinc irridite coating, stripped it down primed with PPG DP 40 and painted aluminum Concept 2000.

CC230, Was it Bob's recommendation to go with the RPM air gap vs. the regular air gap? With my build I don't anticipate going over 5k rpm, but I see a lot of marine builds with the RPM version. According to Edelbrock the regular air gap is a better fit to the power curve in a boat. I just wonder what I'm missing that so many are built with the RPM version. It would soften up the low-end torque curve which would help preserve the outdrive.

Screw the outdrive, it can take most any small block build up...and remember, power under 3k does not really matter.

If you are worried about intake differences and slight loss of low end torque, still get as tall of dual plane as you can, but make sure the plenum divider is fully divided. The regular RPM is fully divided. Just close off the exh crossover thru intake. Felpro #1204 has this blocked.

If you want an Airgap style, but fully divided, the Weiand Air Strike is built this way.

All this aside, the Edelbrock RPM Airgap always makes more power on 383's and larger. Not a ton more, but enough.

SB I've read that as well. Hotrod magazine did a comparison of all dual planes with a 350 and the RPM air gap is better than the Air Gap and the EPS (about 5-10 hp), but the curve is shifted up in the RPM obviously. The RPM performer and the RPM airgap both have the crossover cut-out slot under the carb. I thought the air strike does too, but I'll check again. The regular air gap and the EPS do not have the cutout. I am leaning toward the regular air gap over the EPS solely for reducing intake charge temperature even though the EPS slightly outperforms it. My 383 build is a little higher compression than I wanted (9.9:1) so I'm trying to get everything in my favor to help with preventing detonation. (flat tops with -5 cc reliefs, 73 cc polished chamber heads, 160 deg. thermostat, ideal quench height at .042") My cruising and tube pulling RPM will be right around 2800-3200 so that is my real question does the RPM model catch up by that point to the std. and then continue to outperform on the top end?

You will have no issue skiing and tubing, unless you put too much prop on it. You could put a 500hp 502 in your boat and overprop it and be a pig planing.

Listen, the 383 with any of those intakes will plane 5 million times faster than your old motor.

Nice thing when people in my area ask same question - sometimes they ask about intake, or carb , or cam, or etc but based off same planing speed/tubing/etc - I just take'm for a quick ride in a 5.7 that's been hopped up. The response when gunning from idle is - "wholly schit ! That answers that !" Followed by some laughing.

The notch in dividers help more when the engine doesn't have enough carb. If you have enough carb, you are going to use a 750 right ? The notch is not needed for top hp.

Again, notch or not, the 383 as I mentioned above, will be worlds better than what you have.

Btw, my memory says the RPM non airgap have fully divided plenums pre Vortec and Vortec. Some of the BBC's have the cut out.

Double check on this. but I truly think the cut out was part of the Air Gap rpm difference.

You are correct on the RPM performer, I looked it up again yesterday. Just the air gap has the cutout. I haven't bought a carb yet, was leaning toward 1409 edelbrock 600 cfm. Volumetrically its' plenty of carb under 5000 rpm and would idle / shift better than 750, plus help economy a little. This might be a case where the AirGap cutout helps extend the top end for me then with the small carb. The 305 has the quadrajet and I've rebuilt it twice already in the last year and just like in the past working with cars, I would like to throw it off a cliff. I didn't go real aggresive with cam as I stuck in the XM262 hydraulic flat tappet from Comp.

Sylvan, Bob did not spec the air gap, I told him that's what I thought I wanted to use, he didn't disagree. I had the thought the lines of what SB said, it may soften the low end blow to the outdrive (if even measurable), but I don't plan on hammering it out of the hole either. The cars I've used the air gap on I really liked the response also, so didn't really think to much about it.
Was it a good choice or not? Not sure. Carburetor I think I may go with a QF 750.

94 Sylvan,Take it from my experience with SB's in boats.

If you are not using a mechanical secondary carb, you want one that you can adjust the opening of the scondaries.

This rules out the Edelbrock Carbs.

Against theory and myth, a boat likes the secondaries to open soon. If you get a Holley VAc secondary, make sure to get one with quick change spring set up.

You will crap your pants with the performance gain as you try each step down softer spring. Don't be surprised if you end up at or near the softest spring.

A mechanical secondary carb will use more fuel because of the two accelerator pumps, but it is actually a better system since you have direct control over airflow.

SB that's what I'm shooting for is a mechanical secondary, and also with that, should be able to control the secondary's for some kind of cruising speed economy LOL!

I'm running a Performer duel plane Vortec and a single plane 1" thermal spacer with a mechanical 750 Ebelbrock I didn't fully understand why SB ruled them out. . It looks like your DCR is around 7.4 :1 It should be fine on pump gas. I used a lighter circle track flywheel also. It makes a huge difference in throttle response. Especially for those out of water experiences :D here's a couple videos of my setup at WOT
https://www.youtube.com/watch?v=pB_xViJUs0E

https://www.youtube.com/watch?v=fZ9g6vPaml8

Good running Donzi. Congrats.

The Edelbrock carbs use an 'air valve' for the air flow thru the secondaries. The AVS series feature an adjustable air valve. The Performer series don't have an adjustable system.

The air valve is located over the throttle blades (yes, the blades are connected by 'mechanical linkage) and under the boosters.

I have a nice Q-Jet the was built by JET that ran real well on my old 383 build. Started out redone for a hopped up 5.7 then the 425hp 383. That's about the most I would use it with, but it ran real nice and no Q-Jet bog. I really have no use for it anymore and it's no good for a car. If you'd be interested, I can dig it out.

Oh by the way, I tried a couple edelbrocks on those motors and they never ran as good as the Q-Jet.

Acrooks. I am a Qjet person, and building up a marine 383 now. Tried to send you a pm. I'd be interested in your configured Rochester.

Sorry, I did get it yesterday on my phone, but didn't want to go through the hassle of typing on my phone. I have the carb up at the cabin. If you aren't in a hurry, PM me your contact info and I'll get in tough with you when I grab it in a few weeks.

yup, not a rush...all the water is hard as a rock this time of year