Omc 300 v8 on 21 action?

[Instigator]

The V-8s were produced from 1985 to 1997.

A twelve year production run.
Yeah they must have been turds.

EVERY hot rod V-6 I’ve ever built has been 100% OMC ignition.
Several of them turned 8300+.
I did that intentionally, to prove that a solid OMC ignition would work.
I had a good buddy w/a bad asss V-6 looper that he drag raced and converted to Yammi ignition.
He asked my opinion before he spent the $1500 to do it and I told him what I thought.

He did it anyhow, and I didn’t blame him as he was running 200+ lbs of compression and turning 9k which is where the experts say the OMC ignition gets weak.
He called me a wk later to say he picked up nothing and it was a waste of time/money.
People replace a 20 yr old OMC ign w/a Yammi and say how great it is
Duh.

I used to get calls for help all the time from people that couldn’t get their looper to run like mine.
Always start by asking about the ignition.
They always replied, “it’s all orig/stock but I know it’s not that”.

I bought a ‘95 STV River Rocket w/a ‘94 225 OMC in about ‘2000.
I experimented w/the motor to see what it would survive in bolt ones w/o going inside.
In drag trim, it turned a 22” drag 8500 w/box stock internals.
15 yr old junk.

Remember too, when Yammi started building/selling OBs, OMC sued them for patent infringement.
The heads of their first V-6 would bolt on an OMC!

Everyone thinks the Japs are great engineers but their true skill is in reverse engineering.
So they stole a design from OMC and installed an updated Japanese ignition.
Wow. I’m impressed.

I don’t give a crap if the guy wants to run a Chrysler.
We let him know the pros/cons, let’s let him decide and then support his effort.
Thats who we are.

[Riverratt]

That is your opinion. If I would have listened to your bad advice I would not have had over 10 great years of owning my V8. It was one of the best motors I had.

I am being helpful. I am trying to help someone not to go into the trap of getting an OMC V8 because they think it is cool to have a V8. Too many people have done that and come to regret it.

We know that:
1. Ignition components were not good even when they were new. V4 and V6 ignitions were not good either - that's why people replace them with Yamaha ignitions - and there are fewer parts that need to work at the same time on those engines than on a V8
2. OMC warranty costs for the V8 were huge back in the day - far higher than the 3.4 liter Mercury V6 that was its key competitor. And nobody thinks that it is a good idea to get a 3.4 liter Mercury
3. They had to sell the engines at a huge discount through the backdoor (Second Effort) to get rid of them
4. They stopped making them due to lack of demand and scrapped the tooling
5. The company went out of business due to poor quality

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[V-bottom]

I ran twin1987 V8's for 18 years - 1 standard rotation and 1 counter rotation. The way some of you are talking and behaving like this on a person's thread is pathetic.

I'm afraid to comment anything on this post in fear of offending someone.

21 Action if you have any questions pm me. I have the service manual for your motor and my brother still has 4 or 5 V8's sitting in storage awaiting the right time to put them back into action.

Best of luck with your project.

Doug

[MattGreen]

21 Action: there is useful information on both sides of the “V8 equation” in these posts. No motor is perfect, V8s included, but they are “old school cool”. Ultimately if somebody is an OB fan they will appreciate a well set up V8. If built and rigged right they can be as reliable as anything else OMC. It will be the cheapest torque you can get. Like Gary and Doug said, there are folks here that are happy to help if you want to go down this road. I’m on team V8 too - both my Scarab and Checkmate are being built to be able to accommodate the dirt cheap V8s I’ve been accumulating

Good luck !

Matt

[wideglide55]

If you like working on motors and gearcases and wasting lots of money,by all means get a V8,I had one and no thanks.Not to mention good luck getting parts. My Eliminator was 16 MPH faster with the ProMax that it was with the V8 and I never had a single problem with it.

[Instigator]

16 MPH?

Wow.
Gotta get me one of those Promax things.

If you like working on motors and gearcases and wasting lots of money,by all means get a V8,I had one and no thanks.Not to mention good luck getting parts. My Eliminator was 16 MPH faster with the ProMax that it was with the V8 and I never had a single problem with it.

[Riverratt]

I guess I must have had luck with mine and dodged a huge bullet cause mine worked great, I think it is funny how people bash the V8 but are perfectly fine re ringing a 260 or 280 every 100 hours and sending out the injectors to be cleaned once a year but turning a wrench for minor maintenance on a cheaper motor is not.

If you like working on motors and gearcases and wasting lots of money,by all means get a V8,I had one and no thanks.Not to mention good luck getting parts. My Eliminator was 16 MPH faster with the ProMax that it was with the V8 and I never had a single problem with it.

[FUJIMO]

...does SEI make a gearcase that would work on a v-8?

[MattGreen]

Hi Fuji, unfortunately no direct SEI V8 case replacement. They do make a Magnum equivalent that can be adapted to a V8 relatively easily.
_______________________

I agree with River-Rat - V8s can be reliable if rigged and maintained right. The 260's appetite for pistons, rings, and re-Nik jobs is an interesting discussion point......but I digress....

Here's a real-world example of a reliable V8 based on first-hand experience at the OMC/BRP dealership I used to work at:

Factory rigged 22 Stoker SST with 300 V8. Owner did have an issue with the original early 1990s powerhead. The powerhead was replaced under warranty and double-checked by the shop Master-techs. It was still running the last time I visited the shop (October 2019) ! That is around 25 years - saltwater use ! It has never been rebuilt. This boat was sometimes towed as tender behind the owner's motoryacht. It has gone through a set of VRO pumps, 1 powerpack, and gearcase wear items. The motor has outlasted the original electrical and fuel systems in the boat. The owner loves it and refuses to replace it until BRP came out with a 400 ETEC (so he's SOL now). It has been maintained 100% by OMC Mastertechs and the owner understands that boats needs $100 bills.

I think as mentioned above a lot of V8s issues are due to improper rigging (they do like fuel) and inadequate/inexperienced maintenance.

Your results may vary.

Matt

[Instigator]

I will be mounting a 3 liter Sporty to my V-8 project.

[21action]

Sorry guys Ive been super busy and haven't been getting notifications to this thread. Thank you guys for all of the help. I ended up selling my 200 and picking up the v8 for half of what I sold my Merc for. It is a super clean 4.0 with light weight cowl. It has a couple of small issues and is going to monty next week to go over everything and get it running good. If I end up loving the motor I will send it back to him for some upgrades. It's going to be a little while before I can get to rigging it but when I do I will definately post some pictures and performance numbers. Thanks.

[Instigator]

Good for you.

Congrats!

[FUJIMO]

...I ended up selling my 200 and picking up the v8 for half of what I sold my Merc for. It is a super clean 4.0 with light weight cowl...

...what year was the 200? it was an older one, wasn't it?

[mrichartz]

Start saving now! You will be sending it back to Monty.
You are just having him get it in shape etc for now..
As soon as you run it for a bit you will be ready to have him do the work.. just keep watching the videos of motors he's done you'll be ready in no time.

[dgscroggs]

Start saving now! You will be sending it back to Monty.
You are just having him get it in shape etc for now..
As soon as you run it for a bit you will be ready to have him do the work.. just keep watching the videos of motors he's done you'll be ready in no time.

Those motors in the video’s sound incredible, I plan on getting a back up power head and letting him put his magic on it , someday