The elusive 224/3.7 MerCruiser banger

I was a little concerned about the downward pull of those two bolts to but decided to leave them and use them. The Boss head has 3 different angles on the bolts to deal with. I believe that MerCruiser did not use a bolt there. I still have my stock intake, I will have to look.

 

To some extent, a V-belt driven alternator will act as a vibration damper.

 

You are correct. I just looked at my stock intake manifold. No bolt there. I'm using an A460 head so it has raised runners which increases the gap between bolts in that area. I also want to use the holes in the head for my coolant return to the radiator., so I used them in my intake manifold.

 

That was a good change. Being for a v8 head those useless angled holes would only make trouble. When you filled the holes, what did you use?

I knew (he died) a friend who would have abrasive pumped through his manifold to improve the flow. He said it was expensive but that it was effective. He won races.

 

I am using the rear water port for my fan switch and the front port for my temp gage. On my old manifold, I left out one of the bolts to get the temp and fan ports there. My new intake uses all the bolts, but at the front with a dist I don't know what I am going to do at the front water port to get a temp gage in. I bring water out of the front of the head with a thermostat housing.

 

When one makes a group of changes, it is impossible to isolate the effect of a single bad change in the group. I tried a lower compression ratio and was happy with it as operating problems (detonation and excessive engine heat) went away. When coupled with increased advance in ignition timing, it was a good change for my kind of use of the car.

 

Beautiful casting. It is quite tight near the distributor and its wires, you could cut a concave relief for clearance in the casting. Cutting into the interior is possible as it could be closed up with .065 sheet.
I watched a video in which an exhaust manifold was dented in and it made no difference on a dyno run. Being on the intake side may not be the same and it is on the outside of the bend where al of the flow is. I usually put water temp sensors in the upper hose near the head.

How did leaving out a bolt for sensors or for fan work? (I'm having trouble understanding that).

 

We talked about putting a bump in the port to clear the dist, but then I went of on a off-set dist set up, so it didn't happen. Besides we couldn't agree on where to put it. But the good news is a stock dist will fit if clocked carefully. My VW MSD's will need a bump in the port. And that still may happen!
The Boss head has 7 bolts, at 3 different angles, my set up only used 5 bolts at 2 angles. In this picture you can see where I have the temp sensor. He didn't want to angle it up like that because there is a bolt that goes in the area between it and the manifold adaptor I made, so that bolt was left out when I made my adaptor. Fan sensor is at the rear port.

 

When Beck said he filled and drilled straight in, I though he was saying he put his water outlet in the front of the head. That gave me a idea to move the sensor to the front. So now I will look at that to see if I can drill and put my water temp sensor in the front sorta hiden behind the water hose in that last picture.

 

I drilled my head in the back to access the water port for my water temp sensor. I just drilled and tapped it for the NPT that my sensor was. 1/8" I think??
If you look at the enlarged computer image of my manifold on the previous page you can see a flat bolt head next to the water outlet hose on the left side. This bolt was originally at an angle like those between the ports. I got some aluminum bolts. I don't remember if I cut a slot down the threaded area, or if I drilled a small hole in the bolt. Using an epoxy similar to JB Weld I coated the threaded head hole and coated the bolt threads. I then screwed in the bolts until snug. The slot/hole allowed the excess epoxy to escape and not hydraulic the hole. I wiped off what I could before curing. After curing I cut off the bolt and carefully surfaced the face of the head. I then redrilled and tapped a new hole there at a 90 deg angle to the head face. I install these 2 bolts and the 3 bottom bolts before torquing the angled bolts near the ports. Hopefully this keeps the intake and head ports aligned when tightened.

 

Flatrod17, I contacted the builder of your inline 4bbl manifold. He does really nice work. If I wouldn't have had a connection doing the 3D printing, I would have probably had him build my manifold.

I don't have an issue with my distributor since my EFI system also supplies ignition. I have a GM truck LS coil pack mounted on top of my valve cover. I still have the internal oil pump, so I needed the distributor housing, but the rotor and cap has been removed and plated over.

I am going to have to make wiring changes since my previous single throttle body was drive by wire. My ITBs will be drive by cable. That requires a different IAC and TPS wiring. I also have to completely change my throttle setup which I have mounted on a hand lever, not the typical foot location.

 

Thank you for the explanation, Beck. I really did not think of filling and changing the bolt holes, but I did want to modify them, But Kelly (the builder of my inline intake) really wanted to be able to build a intake for a Boss 429 engine, and I supplied him with dimensions to do so. He did ask me awhile back if I had a wedge head to get dimensions off of, I did not. Must of been when you talked to him.

 

I'm thinking of getting out of this project and focusing on others.

The progress I made is documented many pages ago but if anyone wants to buy a freshened stock engine with an aluminum head I'd be interested in selling for far less than the cost to purchase just the new parts on the build.

 

I have the engine plus three cores worth of parts listed locally for $500 and have interest from some boat people. I would much rather sell it to someone here than slap all the marine stuff back on.

 

It seems like if you want one you can't find them and if you have you can't sell them .

Was staring at the one I drug home supposedly runnable and all that thinking it's a lot of work to get about half a good SBC if that with out major mods. Thought about posting it to gain shop space .
Hearing you can't sell one with a aluminum head cheap is discouraging.

I'm not sure I have the time to do what I wanted .

 

I forget after reading all this .
What was the situation with cutting the back of the block to the correct length to bolt action GM trans right on?

 

Some here have cut 5/8 off the bell housing flange of the block. I did not. I used a 621 Chevy car bell housing, steel flywheel that is identical to the stock merc one. I have had 3 different transmissions bolted up to it and the only thing I had to do was machine the crank for a polit bearing. I will say I used a Mustang T5 Z trans but put all the guts into a Chevy case. So no adaptors but still have the Ford input shaft but Chevy bearing retainer. It was all a simple bolt together with stock parts.

 

Thank you for the explanation on the Ford T5 guts in a chevy case .

I was wondering if one could cut or mill a steel Lakewood or other belly housing face off and reposition it in 5/8 of a inch and weld it or a new face back on . So say a Muncie or Saganaw trans would bolt in like normal .

I can get a bell housing in the milling machine

 

You would be time and effort ahead to just make an insert to hold your preferred pilot bearing in the flywheel like many medium duty trucks do (though they use a bigger bearing and pilot). There is plenty of spline on a standard Ford/Chevy 6.whatever input to allow the disc to ride 5/8 further forward. It would be a very simply lathe project since the holes don't provide alignment.

Edit: Use the flywheel center bore for location and the bolts for attachment.

 

One of the transmissions I had bolted up was a Muncie M21, the other a T56. All of them only needed the crank machined for a bearing. I did make up a piece to hold the bearing in the flywheel, but realized I needed to be in deeper. I will have to say the Ford input in my T5 was the short one, very close to the same length as the Muncie. I think the key to making it work is in the bell housing. I have collected several Chevy housings and can say I have 4 different depths for them.

 

That's where not trimming the 5/8 would help.

There's one common stickout that most Chevies and Fords use. 6.25, 6.125, 6.5, something like that. The exception being 5spd Mustang stuff.

 

After 94 the Mustang got out to 7 something for the input. When I started my project, it was said that 5/8 off the block was needed, that's why I made that piece. Turns out I did not need it and had to go in farther.

 

If you have everything apart and will be sending the block and crank out for machining anyway then 5/8 off and drill for pilot is absolutely the easy button.

I couldn't do that as there isn't the space in the crank to accommodate the pilot bearing that goes with the trans I wanted to use without getting into the flange so I had to move it all back.

 

I am on my 3rd engine now. (none of them have blowen up yet) All have the crank machined for a bearing, none so far have needed to have the block cut. I do see how it can be needed, but the parts I have gathered, it's not needed.

 

Isn't he one of the Administrators of The Home Foundry forum. He has a video of that intake. He has several other videos and threads of other intakes he's done. He does awesome work...!

 

I do believe he is. He did mention that to me when we were talking about making a manifold.

 

Wanna buy three more?

 

I have 4 right now and 2 more I can pick up. I did think about yours, you have a great price on them, but it's the shipping that stopped that. I am surprised you are not able to sell them!

 

It's looking like my 3D printed manifold is a bust. It has been 2 months since I was at that shop and they did the scanning and programing work on it. No trial parts have been printed yet, so I'm thinking they won't.

I saw an interesting post online (Oct 13 date) about a 3.7 with a turbo. It stated his motor had a T3 turbo making 10 psi. No big mods to the block, no intercooler, blow through 2 bbl carb, Edelbrock head, and Joe Hunt mag. It said he was making 400 hp at 3500 rpm. That seems high to me. I messaged the author and emailed his machine shop with no response. If anyone knows this Jeep TJ motor please give us some info!


I would like to try a turbo but in the5000 - 5500 rpm range. 400 hp would make me very happy.
Edelbrock makes their Performer RPM heads in 75cc and 95cc sizes. Any thoughts on which would work best for this?
There are so many turbo compressor sizes. I don't even know what "trim" means in turbo lingo. Getting the right turbo would be the key and I don't have a clue. Anyone else know how to size one?