1973 130 HP... More power?

[Zaairman]

Like the title says, I've got a 1973 Chrysler 130 HP. Runs sweeeeeeeeet, but I'm wanting more power. I saw that they made a 140 HP those years. What would it take to upgrade to that power? New carbs? Also, is there anything else I can do to add power?

 

[Nate3172]

Re: 1973 130 HP... More power?

To be perfectly honest, if it's not broke don't mess with it. These things are not Japanese tuner cars. One possiblity would be to put some aftermarket reeds in it. I have never done this with an outboard engine so I can't tell you if it is a viable way to increase power from it. I have done it alot to 2-stroke dirt bikes and other off-road toys and it works really well. I have only seen one company that makes aftermarket reeds for the Force/Chrysler and that is Boyesen. There could be others though. Never researched it enough. So, short of that or figuring out a way to force induct it inexpensively, it would probably cost you more money to squeeze more power out of it than to purchase a higher horse power engine.

 

[Zaairman]

Re: 1973 130 HP... More power?

So here's the thing... Is this worth $130?

http://www.boyesen.com/cwo.php?stor...category_id=26&category_id=25&product_id=1081

 

[Nate3172]

Re: 1973 130 HP... More power?

Don't take this the wrong way Zaairman, but if you are wanting to try to find some kind of hidden power out of your engine it may be one of those things that only YOU can decide whether or not a bolt on "performance" part will be worth the investment. I've been told, (so this means I have no true knowledge of this myself), that the Boyesen reeds are not made of metal so if they disintegrate they are less likely to damage your engine. Whereas the stock reeds are all metal. If that is true than I guess it could have it's benefits. Although I have not seen or heard of stock reeds ever failing in this fashion, I suppose anything is possible. Here's a thought, have you tried doing some research for a differen't pitch prop to possibly utilize your engines power differently?

 

[Zaairman]

Re: 1973 130 HP... More power?

The Boyesen reeds are fiberglass. And as for my motor, they make two props. A 17p and a 19p. I own both of them.

 

[Frank Acampora]

Re: 1973 130 HP... More power?

I don't remember exactly, but I don't think the 130 was a stroker engine. The 140 and 125 were 3.375 bore and 3.312 bore by 2.86 stroke for 104 and 102 cubic inches respectively. I think the 130 was the regular 2.80 crank with either 99 or 101 cubic inches displacement. HOWEVER, you can not just replace the crank. You must also raise up the ports by about .060 to put the timing where it belongs.

Now, if you want to wake up your 130 a little: If it does not have the big bore TC carbs, get the big bore manifold covers and two TC-4A or TC-5A carbs(1 5/8 venturis.). That will give you a few extra HP. If it has the 1.78 to 1 lower unit, get a 2 to 1 lower unit or gear pack--lets the engine rev up a little more and you gain a few HP. But you still will need to go up 2 pitches on prop size. If you want to open up the engine, port the bypass side only. If you port the exhaust in a non racing application, you lose what you gain from porting the bypass. To see porting, go to Chrysler Crew, join, and then go to pictures--Franks boats. I have a couple of 3 cylinder port jobs in the album. You can also drill 4 or 5 evenly spaced vent holes about 3/8 inch diameter in each side of the lower unit case about 3/4 inch above the cav plate for less back pressure. (Behind the gearcase oil chamber please. Roughly above the prop.) Counter-sink them with an 82 deg. countersink to roughly 3/4 diameter. This gives a trumpet shaped port that passes more exhaust than an equivalent sized straight hole.-- However, this is not strictly legal--it is a cut-out and quite a bit noisier. Oh yeah-- If you have a points distributor. (one wire coming out the side) get an electronic electric eye distributor (two wires coming out the side). It has a little better contol over timing. That two piece lower unit and midleg is about 1 inch longer than the newer 1 piece lower unit. depending on your hull, you may need to raise the engine 1 inch to get the cav plate even with the bottom of the hull.

But don't expect miracles--even with all the mods, you are still running an engine designed over 50 years ago. You might get 140-150 --maybe even 160 if you are real good and real lucky but that's about it. And prop selection is very limited. You are really going to need to hunt for what you need. and the extra HP will only translate into 4-5 MPH more speed on your existing hull. Maybe a little more if you are lucky.

 

[Zaairman]

Re: 1973 130 HP... More power?

Frank, thanks!
A few extra HP and a few extra MPH is all I'm looking for...right now. I'd like a newer motor, but this one runs too good and I don't have enough cash. I sent in an application to join the Chrysler Crew.
Now, what are big bore manifold covers? And where can I find them, along with the carbs and 2:1 gears?

As for the lower unit, I'm looking into getting a jack plate... The motor will be needed to be lifted much more than 1" to get the cav plate even with the bottom... DOH!

Here's a link to some boat and a few motor shots...

http://s140.photobucket.com/albums/r18/Zaairman/1973 Tahiti/

 

[MikDee]

Re: 1973 130 HP... More power?

Nice lookin boat! It must hual arse pretty good? lots of luck with it.

 

[Frank Acampora]

Re: 1973 130 HP... More power?

Look at your engine. If you have the big carbs, there will be stamped the letters TC---on the mounting flange. The manifold cover is what the carb mounts to. WB carbs have a 1 5/16 venturi and about a 1 1/2 butterfly and hole in the manifold cover. The nuts that hold them on are 1/2 inch. TC carbs have 1 5/8 venturi with about 2 inch butterflies and matching holes in the manifold covers. The nuts that hold on TC carbs are 9/16 inch. Buying these parts new (if they were available) would be prohibitive. Even used is expensive. You need to hunt up blown engines --Chrysler 125 and 140, and Force 125 will interchange for carbs manifolds and reeds. Early Force engines were nothing but re-badged Chrysler engines. Unless I miss my guess, the 90 Chrysler was the only Chrysler with 2-1 gears. You can still get new gears, but they are expensive--about 600 for the gears alone. Force lower units will not interchange and neither will the Chrysler 1 piece lower unit. Gears are completely different. Electronic distributor? 78-79 for sure, maybe other years--you need to look or ask. Must come off 4 cylinder engine.It will be expensive even used. You need to hunt for these parts, ask around in the classified section of Chrysler Crew, Look around ebay, try to find junkers in marinas near you. I know where I can find a 2-1 lower unit but It aint gunna be cheap. That's why I don't have it in my collection yet.

 

[Zaairman]

Re: 1973 130 HP... More power?

Nice lookin boat! It must hual arse pretty good? lots of luck with it.

Thanks... It'll do about 45-50 with the motor trimmed all the way down. But, my power trim is being rebuilt and resealed as we speak...

And Frank, I'm currently 110 miles away from my boat and motor, so I couldn't tell you what carbs, ignition, etc it has on it.

 

[Zaairman]

Re: 1973 130 HP... More power?

Hey Frank, on that pic of your port job, what size did you make the ports?

Also, on that Outside Transom Repair pic, are those the holes you were talking about?

 

[Frank Acampora]

Re: 1973 130 HP... More power?

The ports are actually the same height as the diameter of the original ports but slightly wider. In other words, I did NOT change the port timing, but they are a lot larger--25 -35 percent and look even bigger. On that particular engine, I gained about 10 hp per cylinder and about 8 MPH. But that's a 3 cylinder and on them you can port the exhaust. (120 deg crank throw and about 120 deg port opening---no overlap. 4 cylinder has about 120 deg port timing and 90 deg crank throw for a 30 deg overlap--thus exhaust blows back into the cylinders --especially #2 and #3 and especially when ported.) You do realize that it is not possible to port with the engine assembled. It must be completely taken apart so it is accessable, and can be readily cleaned. This is the type of modification that you do if you melt a piston and need to rebuild the engine. Unless you are a die hard glutton for punishment. And you should also realize that there is a slightly greater chance of a ring catching in a port. Porting takes about two hours per cylinder--you need to work slowly and accurately--unless you know someone with a Bridgeport mill.

All I did was to take a Dremel with a flex shaft and a carbide bit. Used a 1/4 inch tapered HSS bit for the aluminum and a 1/8 straight carbide bit for the cylinder liner. I squared the ports and streamlined the webs between the ports into an airfoil shape. I also tapered the aluminum on the bypass below the ports. The piston does not expose the whole port, (does not go down far enough on the bypass side) but because the aluminum is tapered inward, it "sees" or thinks it "sees" a bigger port. Use the Dremel at a fairly low speed--about 1/2 and keep dipping the bits into cutting oil. Otherwise the aluminum will gall and clog the bits. I also slightly chamfered the inside of the ports to help reduce the possibility of ring catching.

Yes--if you are talking about the 4 holes visible in the lower unit, that's them. That is a one piece lower unit. Your two piece is slightly different but similar. Look at it while off the engine to determine where the holes can go without interfering with anything. One thing I am going to try is to drill holes straight downward from the inside of a two piece lower unit right through the ledge where the mounting bolts pass up through it. I won't be able to countersink them but, that way, they can't be easily seen.