Please help how to rig my AE21

[lowlifeAE21]

I have a 1990 AE21 with a 1999 mercury 200 merc carb with low pick up gear case with a 4" set back attached to a 10" setback hydrolift and a tempest 26pitch prop. I have a 28pitch chopper but dont have the power to spin it. I know I need more hp for this boat but its what I have to work with for now. I was just woundering what I can do to get more hp out of my motor and if there is anything I can do to make my set up better.

[Jimbo]

The good news is that you have a newer 2.5 liter Merc.

The bad news is that hull needs 240+ prop shaft horsepower to make it fly.

But, you can help yourself with a simple mod that can get you 8 to 10 horsepower improvement through most of the power band. Just cut the heads to give you 35cc volume and use a 1mm head gasket.

Get a reliable guy to do the work like Jay Smith or Randy at GPI. You will also need to start using premium gas if you do this mod.

There are other things you can do like Boysen reeds, velocity stacks on the carbs, and some exhaust relief work. However, to get some serious horsepower you need to go inside the engine and do some work with the ports.

Start with cutting the heads, this gives the biggest bang for the money.

Jim

[hsbob]

jimbo basicly right, but give us some numbers. there maybe something that we can suggest???? need info

[lowlifeAE21]

What kind of numbers do you want? I have GPS and ran with it this morning and the best I could get was 77.4 mph.

Jimbo where is jay smith or Randy located? Because I live in montreal, canada. Do you know of any good places in with in 400miles of here?

[Jimbo]

Hello Again AE21,

First let me say you are doing good with a 77+ MPH with just a stock 200.
Probably, the best you can hope for with that power is aother 2 to 3 MPH.
You stated that you had a low water pickup. I would try to experiment with your motor height ( raise it up and down to find your best speed ). Be sure to look at your water pressure gage when you are doing this, don't let the pressure get below 12 PSI at WOT. That Tempest prop you have is a good prop --- it has a 14 5/8" diameter, this will allow you to take full advantage of that low water pickup. The next setup thing you could think about would be your setback. Most people with that hull find they need at least 10" of setback ( distance from transom to motor mounting brackets ) with many finding they need 14" to really air the boat out.

Good luck with all of this!!!

Here is some contact info; I don't know anyone in Canada:


Randy Pierson
GPI
Gran Prix International
213 1st Street NW
PO box 146
Avon, MN 56310

Office: (320) 356-9068
Cell: (320) 267-0440

_____________________


JSRE
Jay Smith Racing Engines
12807 Erin Lane
Dayton, Texas 77535

WWW.jaysmithracing.com

[lowlifeAE21]

Thanks again for the info jimbo.
I just came back from a dealer not far from here and they have a 2005 merc 225x for sale. My question is, sould I bother moding my motor now or just sell and pick up the 225x. Will there be a big dfference or in the 2 motors?

[Balzy]

on the 225X. It isn't gonna be close to what you need for HP to get the hull to start to work for you. I agree with Jimbo except my feeling is you need more like 265 HP to get the hull to really work to the point and air out so it will lift the hull far enough to get the thing to ride the gearcase. That's the way the AE's and HST's finally get going fast. The best my HST did with a 200 EFI modded to about 235 HP was 87.?. To get near or break 100 you will need a horn motor. Even a stock 260 will just get you to 102 or so on a perfect day. A 260 is pretty easy to get more HP out of and you will be able to get near 110 then.

Jimbo is right again. You need a ton of setback. Randy P will tell you different but he and I never agreed on that. LOL. I run 16". I shortened it to 14" once and the boat hated it. I started with 8" and that was a waste of time. If I read your post right you are at 14" now. You aren't far off then. You need to get as much weight in the tail as you can. Move your battery right up against the transom behind the fuel cell and the short wall that runs across the boat. You will need to make a holder of some sort for it and strap it to it. Move your fuel cell, pumps, and whatever else you can back as far as you can also.

Then do like Jimbo said. Start working your motor higher. Run it up until you are where you need to be with water pressure. Also a torque tab welded on your skeg helps keep the motor straight and helps the handling and speed a bunch as you jack the motor higher. Keep us informed on your progress.

Go to http://www.hydrostream.org/Specific%20Models/Models.htm and click on HST and read the article I did years ago. There is also a good pic of my setback. I built the bracket myself.

[freddieorr]

not sure if my experience will help or not - but about ten years ago I was running an 89 hst with an 89 2.4 efi and had the boat consistently running 98-99 mph - best run was 102. I don't remember my setback - but it was at least 12"s, biggest two changes for me were getting rid of the gear case - I am not much of a tech, but I believe it was a mod vp? it had cresecent shaped pickups above the nose of the cone... I could not get the motor high enough with this case without huge blow out - so I Switched it just for kicks one day with a stock lower unit that had a bobs nose cone and pickups below the cone...instantly went from about 85-92 then switched from a chopper to an out of the box OMC srx 29" and that was it. My motor was competely stock - never gps'd my boat but was running a liquid filled Gaffrig... so had to be pretty close. I couldn't believe how much difference those two things made - and they were not expensive. As well - I have known guys to play with AE21's as I am from Canada too... and actually had some dealings with the builder of these boats... nice guy...but I have never heard of anyone getting as good speeds as the American HST got... never heard of one doing much better than 90...even with the 2.4 EFI motor

[Balzy]

I would have had this kind of wealth of information when I started working with mine back in 1997 !!!!!!!!!!! Wow, could I have saved some time and money !!!!!!!!!! S&F rocks !!!!!!!!!!!

freddieorr - The resaon your speeds climbed so much is because you finally got the gearcase high enough. The 27 and 29 SRX's do run good on these boats also. Good choppers, ET's, Hoss, all run good on them with the right set up though.

BTW, I have tried just about every gearcase out there. A Bob's coned CLE is the best case I have run. That's what I still run today and that's what I keep here for a spare. Until you get closer to mid to upper 80's a coned case will slow you down over a stock CLE though.

What are you running for a gearcase now?

[freddieorr]

I am running hot air right now... no boat. Sold my HST years ago to a guy who flipped it and nearly killed himself in it in the thousand islands on big waves... Thinking about what to buy - hard to beat the rush I got out of my HST, but want some more space now... and maybe even something that can handle a little more water... so surfing scream and fly to see what I can find out about 22-25" tunnels... or I am just gonna buy a Vegas or Voyageur XT hull... they are way cheaper than bigger tunnels!!

[Jimbo]

Hi again AE21,

Balzy and Fred gave a lot of good info in the posts above.

Balzy has several years experience with the HST which is the American version ( Hydrostream ) of your Canadian AE21.

The question is --- how fast do you want to go?

If money is not a problem, the easiest solution would be to buy the 225X the dealer has. You would need to do a lot of work on your 200 to equal the power the 225X has, which is around 240 HP at the prop shaft. This 225X depending on props and setup should get between 84 and 88 MPH. Also, you would have the new motor guarntee that you would not have if you modified your 200. Also, the 225X has been reliable and dependable based on the guys I've talked with that have them.

If you are thinking that you want to go 90 MPH and beyond, then you will need a 260 or 280. The 260 you will have to find used. The 280's are no longer in production but you may find a dealer that has one they would sell you.

Anyway you need to answer the question how fast do I want to go and what am I willing to pay for it.

Good luck!!!

Jim

[lowlifeAE21]

Thanks for all the info! To be honest I would be happy in the 80's for now, is that possible with minor mods to my motor now? This weekend im going to replace my gas tank and battery. Also what would the best motor be for my boat?

[Jimbo]

Hello again AE21,

Are you satisfied that your motor height is the best height for top end speed?
If the answer is yes and the 77+ MPH is your top speed, then you need to modify your 200 or buy the 225X if you want to get into the 80's.

This is just my opinion, buy the 225X and save yourself the trouble of modifying the 200. The 225X with a sportmaster lower unit with a good prop and setup will get you into the 80's.

Again, if your best speed is 77+ MPH, then minor mods may not get you to the 80's; or what do you mean by minor mods to your 200?

Jim

[lowlifeAE21]

Hi Jimbo,
I mean if I were to put 2k or a bit more on the motor what could I get from that? I would love to get the 225x but the guy wants 15k can for it and I dont know what I could get for my 200?

[JWTjr.]

Weigh your boat first. Most fast HSTs and AE-21s will weigh under 900 lbs. (hull weight). You'll have to do some math; weight the trailer seperately and subtract it. Most 200 Mercs weigh a shade over 400 lbs.; 50 lb/s for battery, and average another 200 lbs for rigging with empty fuel cell. If the hull is heavy of course you have a tougher road ahead of you. As Balzy said, get all the weight possible toward the stern either way. If it's really heavy (over 1000 lbs.) you may want to remove serious things like floors--and do a quality rebuild on the inner structural components. Hate to sound negative but the core/stringers are probably saturated anyway. Most are.

Also check the bottom. Most of these had hooks, taking these out (all three sponsons) and sharpening the edges will help more than horsepower.

Setback is more crucial if the boat is heavier. The MOD-VP hulls (HSTs) were lighter (600-700 lbs). so they needed less setback. The "interior" hulls need all the help they can get. I've rigged and set up dozens of these. With a good stout 2.4 carb engine, lots of setback (15"), a good long gearcase and a good lifting propeller you can easily get into the 90s with one aboard. With two you'll be lucky to hit 85+. To overcome that requires--you guessed it--more horsepower and torque. You can, with the combination of weight removal, bottom tuning, a long gearcase, good propeller (these guys mentioning OMC SRXs are right on, BTW; that prop or a good Mazco RE is what you want) and some mild mods to your existing engine, get 90+ mph speeds from that boat.

JWTjr.

[PhastBoat]

Throw cubic inches into it and it will fly!!!!!!!!!!!!


http://hydrostream.org/SpotlightArchive/Johnson1.jpg

[lowlifeAE21]

Thanks for the info JWTjr.,
what kindof mild mods can I do or mods in general? I really dont want to spend more then 2k. I know I keep bugging you guys but can you make me a list of mods please.

[GPI Racing]

LowlifeAE21,

After reading all these posts most of the guys have you in the right direction. Like Balzy said, we didn't always agree on the set back etc., but for the most part the guys are right. With limited power the "lever arm" will be more important than if you had more power avalible. The only AE21 I've had experience with was quite heavy. I made the guy take all the seats (rear seat too) out on a bet, betting him it would pick up lots of speed. It did, with him sitting on the floor he was 8 mph faster. This proves the need for lift, like the guys say. Try to find a nice 26 chopper 2 and experiment a little with height and weight placement ( ie: moving everything not tied down rearward) Finding a nice set back that isn't made from multiple plates can be your next project.

Randy

[Jimbo]

Hi Ae21,

JWTjr is giving you some good info. We have not talked about the hull because I made the assumption you had checked out your hull and made sure you had no hooks in the bottom and you did not have any water soaked stringers or transom. Clean up the hull and reduce the weight were you can if you have not done so.

It seems you are heading in the direction of modifying your 200 carb. OK here is a start:

1. Cut your heads to 35cc or if you know you can get quality 93 octane cut them to 34 cc with a 1mm head gasket.

2. Open up your engine and let it breathe ---- take the stock air box off the carbs and put on some velocity stacks, remove the inner exhaust can from the tower housing and drill exhaust relief holes just above the cavatation plate (five 1/4" holes on each side), install Boysen reeds, and rejet the carbs to compensate for these mods, ( start with two jet sizes larger).

This is just a start but it will help. For some really big improvements you will need to recut your ports.

Also, make sure your switch boxes do not have rev limiters in them. Merc started this but I'm not sure which year they started. Check your part numbers!!!!

You need to have hard ( solid ) motor mounts. If you don't, be sure to take care of this when you do your exhaust relief work.

Good luck.

Jim