225 HP 3.0 vs. 225 HP 3.0 HO block

[action20]

has anyone put these things on the dyno to see what the actual differnce in HP is ???

considering an HO block. I'm not sure if it is worth it.

Thank in adavance,

Scott

[spanky2002]

i think the HO puts out about 247hp.

[Instigator]

242 @ the prop, 254 @ the crank

Very stought motors for a JohnRude.
Differnces are minimal though. H.O. exhaust ports are about .250 - .300" wider and the exhaust bleed holes are smaller equalling about 10 more psi compression.
Plug your bleed holes and open the exhaust ports (jetting of course) and you will be able to out run most of them.

[Instigator]

I got a p.m. from Action20 asking for some help on Johnnie's and instead of keeping it private I thought I'd give him a few tips in case there might ba a few more of us rare/stupid birds out there;)

On numbers, any of you Guru's reading this feel free to correct me.
I think his Venom is around 220-225 @ the prop. His question to me was wether I thought it would be worth trading up to a 225 H.O.
Stock to stock I think you're only looking at approx. 20 HP's improvement @ the same RPM.
He also asked me about removing the air box and jetting. Trust me on this one, DON'T DO IT!!
On a stock motor it will only make more noise.

As far as the OMC Guru's, there are three that are the best of the best and here they are in no paticular order.

Acie Stringfield of Acie's O/B's in Texas 281-339-3871
Gordon Montague of Monty Racing in Fla. 561-336-9508
Al Stoker of John's Custom Marine. in Ca. 714-827-7920
(I have used the bottom two on my proojects with 110% satisfaction, Acie I've never done biz with)

Acie and Gordon (both past cahmps at the drags) are deep into drag racing O/B's, and also build killer lake motors.
Stoker is an X multi Natl. Champion in endurance O/B racing.

To answer your question, it depends on what you want, your budget and your abilities as a mechanic/assembler/tuner.
If you are confident in your mechanical abilities (can assemble the power head) I'd find a clean '93 and newer (already has finger ports) blaock and case and send it to either of the 3 above with instructions to grind you a "hot" lake motor. All three of these guys will ask you specific questions to decide how far you want/afford to go.
If you don't/can't do the assembly your self, send them the whole power head and tell them the same thing!!
Many, many people have tried to do it all them selves and failed/ruined a good block. It's all in the porting and w/o 20 yrs experience behind you, it's impossible to know where to cut.

Al Stoker did an article for Hot Boat magazine a few months back about hot rodding a Johnny and is an excellent article. While it does'nt tell you exact specs/deminsions it does tell you the correct parts to use and what to look for/at.
It was in the March '03 issue and I learn something more and more every time I read it.
For instance, I already knew that it cracked the 300 target he was after, I knew he reatined the stock 6700 rev limiter, I knew he did it on pump gas and I knew other than Boysen reeds, it was all OMC factory fishin mohtar parts, but on second glance, the dyno sheet that he printed realy got my attention.
How bout this for torque?
271 @ 4100, a peak of 288 @ 5500, and never dropped below 238 until after 6600 (remember the 6700 limiter)
Or H.P.'s?
240 @ 4600, a peak of 309 @ 6K, and didn't drop bellow 300 until 6600 where it made 299.4!
That means at almost any cruising speed you'll be making well over 200 HP's upto it bumps the limiter @ 6700.
That puts you into the low 90's w/a 29" SRX which those boats love!!
I got the chance to tun two different Actions on one of my trips down to Fla.
One was owned by my buddy Lloydster and his is I belive an 18" and was powered by a box stock '89 GT 200 (non finger port) motor and was running 84/85 w/both of us in the boat and I think Lloyd has since gotten to 90??
The other was Monty's boat and was I believe a 19' with one of his lake/sleeper motors on it. This motor had an air box on it, stock cowl, everything. (Gordon has a **** pile of experience/knowledge of/with the Actions including sveral V-8 powered versions that were way over the 100 barrier)
That boat ran 94.5 GPS with 2 of us in the boat @ I believe 7400!!
Hope this helps Scott, and let me know if you need anything else.
Glad to help.
P.S. I have a H.O. sleeve that I can make a port template from if you are wanting to do your own work. Personally, I'd go beyond that for your boat.

[action20]

Thanks for all the info and time Gary !!

My motor is a figer port motor.(1997) I'm assuming i can tear down the block or leave it assembled and send to one of these guys and have them make it an HO ??? They would just be posting the exhaust t h HO specs ??

I was thinking HO becuse i'm trying to keep as close to the stock platform as possibe. 20 HP is a really good HP gain in my book. I think with the boat dialed in with an SRX (was told by others that that prop runs good on actions) should see 90 on GPS and i would be very happy !!

Thanks again Gary !

Scott

[mikej]

Scott, here is a pic of a 3.0 Acie built for me. He is a staight up honest guy. He will treat you right

[mikej]

one more

[mikej]

last one

[lilabner]

here's my 2 cents worth....did some business with Acie..he's a stand up guy..very smart guy on engines...I also know Monty pretty well...he's an OMC Guru if there ever was one...don't know Stoker but have watched him for years....he has to be considered super with his background.....

[Instigator]

Home brewed?:p

[GO FAST BOATS]

mikej
what kind of numbers are you see with the johnrude?

[action20]

You guys rock !

This board is invaluable for the exchange of information.

I will contact them and ask them what they think.

I also want to know how fasf that HO is on the STV !