18HP Vanguard need more power!!

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Thread: 18HP Vanguard need more power!!

  1. #1
    Join Date
    Nov 2007
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    Tallahassee, Florida
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    196

    18HP Vanguard need more power!!

    Hey Guys,

    If you've been reading the ASX tire thread, then you know that I am looking for some more torque/HP for the 18 Vanguard.

    What are your thoughts?

    Here is what I have done so far. Installed double valve springs and billet spring retainers from EC Dist. Also installed thin head gaskets. Have the stock flywheel key. I have a cutaway, but didnt see much difference so I went back to the stock.

    I would prefer to add on some easy bolt on's without doing the cam right now. If that is not possible, then I might as well do the long billet rods, cam and shaved pistons.

    What are the thoughts about a lightweight flywheel, different carb or carbs, modifing the stock carb, modifing the exhaust.

    If you have links for suppliers, that would be great. I have been researching a little about cams, and would prefer one from new stock materials that have not been welded on.

    Thanks in advance for your help,
    Rut
    Last edited by fulleraviation; 04-05-2009 at 07:43 PM.

  2. #2

    Thumbs down MORE HP

    FULLER, Pull the 18 briggs sell it, and install a 25 or 30hp kohler with big clutch. You'll be glad you did, there is nothing better than having enough power at hand when you need it I had a max iv with 18briggs 70% of the time it was ok 30% I was unhappy

  3. #3
    Join Date
    Jun 2007
    Location
    Tulsa, OK
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    That might be the best path. The 18 will make 30-35 hp but not at 3500 rpm. It might do 25 at 3500.

    There are a few things to do that are more time than materials.. a header with good primary tubes and collector(but I have no idea what your IV's muffler looks like anyway). EC for flanges and heymow for tubing supplier links.

    Head port work. Send to George for basic job. Would love to try a lightweight flywheel. The engine revs quickly like a two stroke. No good for our heavy vehicles, I fear. Would be fun to see the throttle response in a 500? lb ATTEX though. The ARC flywheel doesn't have magnets for the stator, so there is no charging system under the flywheel possible. Pretty much makes you say, nevermind. EXECPT certain ATTEX owners It is a safety flywheel, expensive peace of mind. Uses a "real" starter.

    The carb, drill the main jet to .040 after the header. Mine made plenty of power on that 1 bbl. Other option is a 20 hp intake and 2bbl. Sounds cool, but the barrels are separated to different cylinders. Helps but not the best bang for buck upgrade.

    Cams.. Precision Cams. Enough said. George stocks some of them. In 2006, Precision was regriding cams, mine was done in a "265" profile. Easy on the valve train(stock rockers). They now use new blanks and have more agressive profiles. The welded cams are do it yourselfers or that Don Geiner guy who cobbles up flathead opposed goodies.

    Cam, compression, and fuel is where real power will come from. It's a slippery $ slope, mainly because the starter system will be borderline after losing the compression release of the stock cam. A real starter and matching flywheels is $400? I don't have them.

    George would take your engine and put 16 hp small chamber heads, cut them .040, use a thin gasket. Along with long rods/flat top pistons. 100 octane, a Precision cam and an advance key.

    I did long rods/shaved to flat tops, didn't cut the 18 heads, and used the thick stock gasket. A little port work. Header and drilled jets. Those racer guys are never below 4 grand, while our engines have to labor at lower rpm's. So I didn't go crazy on compression OR ign timing. That means your key might be cut a little too much. It might be 34, where I run 27 degrees. The timing is static, so it has full advance at idle.. not great on high compression engine @ low rpm/full throttle. I like to bring the rpm up off an idle before I cram it. Otherwise you can get spark knock.

    Tuning the drive clutch helped a lot because it was limiting the engine's rpm.
    Last edited by Roger S; 04-05-2009 at 10:20 PM.

  4. #4
    Join Date
    Nov 2007
    Location
    Tallahassee, Florida
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    196
    Roger,

    Are you still running the 18 Vanguard, and do you find it reliable with the mods that you performed?

    What are you running for fuel?

    I could spring for the new engine, but thought it would be fun to mod the 18 some more. I would like to know that If I went to the expense of moding the 18 that I would be happy.

    I am happy with it now, and don't run into the boggin down of the engine during my normal riding. This only occurs under extremes like the suction mud in the bog this weekend.

    That's for the advice. I will call EC Dist. today.

  5. #5
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    Nov 2007
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    Tallahassee, Florida
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    Here is a link to a thread where we discussed similar information a year ago. Good Stuff.



    http://www.6x6world.com/forums/engin...-question.html

  6. #6
    Join Date
    Jun 2007
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    Am still running the 18 I built 2 years ago.

    Have used 100 low lead AV gas.. now I carry quarts of tetra ethyl lead additive and add to pump gas. The AV gas is probably safer for humans, while the additive is more convenient, esp on long road trips. Kemco Octane Supreme 130, ordered online.

    Whether to build or buy a bigger stock engine.. hard to say. I'm a mechanic who built my first small block chevy 40 years ago.. and my vanguard reminds me of the good ole days. A big, stock engine running on low octane is what most guys would upgrade to. But if you're going to turn 5 grand for top speed, that's a stretch for any stock engine.

    A 23 vanguard w/50 amp alt would be nice, sell the 18.. use your existing clutch. Pretty cheap route.. still a stretch to run it 5 grand w/o billet rods. If I was looking for a 23 vanny, I'd try to buy it with the real starter/steel ring geared flywheel, for future mods. What would a 25 or bigger kohler cost.. with clutch and everything

    If you build your engine, put an oil pressure gauge on it before you tear it down, some are low from the factory and I did a couple things to get it up.

  7. #7
    Join Date
    May 2007
    Location
    Kings Mountain, NC
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    For the money, it's hard to beat the bandolero motor. I finally got mine complete in time for Busco and it had tons of power. Check out 600 racing for more info: 600 Racing | Home

    Just a thought if you go the new-motor route.

  8. #8

    max

    I agree with mike ,I have the Bandolero in Max IV and my Max 2 and never seem to run out of power and it will keep up with the superchief off the line until about 35-40 mph. You can find the motors refreshed from a racer that is stepping up to a newer car for under a grand, it's the best bang for the buck, PM me if you want more info .

  9. #9
    Join Date
    Nov 2007
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    Thanks for the info on the motor, but I like to work on stuff so I am going to do a little work on the 18.

    I would also hate to have an almost new motor lying arround.

    Talked to John at EC Distributing. He recommended COMPRESSION. I am going with a long rod setup and thin head gaskets. He did not recommend a cam unless I wanted to turn more rpm's. His opinion is that I would loose some bottom end that way.

    I will run it this way, then probably play with the stock carb. EC can rework it for $300.

    Not sure how fast I will get the parts, but I will keep you posted.

    Rut

  10. #10
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    I like that plan and forgot to mention it. The stock cam will not cause you the cranking problems. I've wanted to see how compression and the stock cam worked out.

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