200 to 225 conversion

[garycorbett]

I picked up a set of 225 carbs off a 1994 OMC and I want to convert my 1996 200 to a 225. The carbs have 64D main jets in them. I was told to get a set of 72Ds to put in them. My question - why are the 64s not suitable - too lean??? Why did they put 64s in the 1994 225s??? Any advise you have in making this conversion would be great. I have been procastinating on this conversion; the 200 was working good until last weekend it is leaking gas out of one of the carbs and won't keep running and runs rough when you get going. Maybe it's time????? Also the 200 is very cold blooded and you have to really warm it up prior to a tournamentstart especially in cold weather.

[lkhartwl]

one of the guru's will be on shortly but if I am not mistaken( and I usually am wrong) 1) you need more than just a set of carbs, 2) they may or may not consider it a hop up and well they will tell you they only do factory setting type things. one may IM you but if you are looking for a hop up you need to go to scream and fly, as they will be more helpful in that department. Steve

[garycorbett]

Not a hop up - just 200 t0 225 and I believe on the OMCs the carbs in that year range are the only difference.

[Neveredge]

It is in fact a hop up and I doubt you are going to get anyone to tell you what jets to use.

The reason is that the loopers are very sensitive to carb and jetting changes and the possibility that you will blow it up after the carb swap (very likely) is just to much of a chance for someone to tell you what to run.

You will have to do high speed jetting in order to be sure you are running the correct jets. If you don't have experience with this procedure then you would be best to take it to a high performance shop that knows how to do this.

You also didn't state which 200 you have, if it is the high performance series (vidicater, venom) then it may already have the 225 carbs.

There is a lot of hidden power in these motors but it is hard to get it out and every change you make will require a jetting change.

I understand that you think you are exchanging stock parts for stock parts but with these loopers it is never that simple.

Good luck with unlocking the power. Just do it right and you will be very happy

[lkhartwl]

Thank you Neveredge........ Fred See I did learn something hanging around being a pita

[garycorbett]

It is called a 200 venom but I measured the carb throat diameters and they are 200 carbs. Other than the venom sticker it is a stock 200. Some venoms had 225 carbs I was not so lucky. The 225 carbs I got are 225 as I measured them and they are to spec.

[THE WITCHDOCTOR]

The 72d jets came stock in the 225 ho motors from the 98-2000 period..... I think the bodies where a little different as well....

[Neveredge]

I looked thru the parts catalog and your motor does not have the same heads as a 94 225. That would by itself call for a jet test.

The 96 carbs are the same as the 94 225 carbs so it would seem that it would be an easy bolt-on but I myself wouldn't do it without high speed jetting being done.

Also, those carbs do have 72Ds in them. If the ones you are looking at have different jets then thats something else to worry and wonder about.

Just take it to someone who knows how to jet it and be done with it, then its off to faster land.LOL

[Neveredge]

Also, if your motor is running really cold then it might be time for some new T-stats.

[garycorbett]

My compression is 105 on 5 cyls and 100 on the other. Yes, I think that someone took the 72s out of them before they sold them. I am going to look at every jet in them. The seller said that the the motor had seized a piston or 2 - no doubt if it had 64s jets in it. I was told to go : 72D mains, 36 idles and 30s mids.

[Neveredge]

You can pick up alot of ooomphhh for not a lot of cash by just switching heads. Of course you will need to re-jet afterwards. A set of 86 GT200 heads will boost your power a good bit. Or you could get a set from Madefi for about $500 in any chamber size you need. 48CC should get you about 140 psi.

You will need to run 93 octane with those heads.

[garycorbett]

I can get parts for wholesale - could I get the factory GT200 heads - or are the mad efi modified heads (no doubt) - what psi would the factory parts be???? My brother is not a fan of high compression - says the reliability of the motor really goes down? True??