140 cross -flo.

[terry taylor]

Anyone know how to run a 140 cross-flo. 7,400-7,500 RPM. with out useing the [strangler[ v4 8 barrel carb. system thanks?:)-----------------------------------The set up is a viper.

[evilrude 1]

Maybe a diff. "tuner" -L-O-L-
(remember me)

[racer]

We used to run the stranglers with the standard 4 barrel intake in order to run a second class it would loose from the 8 barrel but could still get them well into the 7k range.

[terry taylor]

Does this mean you ran strangler moded power head, as opposed to production 140 v4 thanks ?:)

[Superstocker]

I've been running a 115/140 conversion on my viper for 2 years now and have turned it up to 7600 rpm for a while. The engine has factory porting & pistons(non-scalloped) and that was as far as I wanted to push it on a lake motor. Now besides sounding great at that rpm(nothing sounds like a v4 crossflow IMHO), I have since propped it to turn ~6700 hopeing to make it live a little longer.

There is nothing special about the engine either; 140 heads, '77 tuner, cut can, 1 5/16" carbs, boyesen, etc. The cylinder porting has not been raised but, everything has been radiused. Including the bubble-back & block where the exhaust re-enters. I have upgraded the wrist pin bearings though. A simple build on a really simple engine that runs great and makes awesome fuel mileage.

I have been thinking about building another powerhead with the 2.6 v6 mods( a la Racer) but this thing is running so well I'm undecided... Good luck with your build and if a v4 crossflow makes you smile at 6000 rpm, you should try 7600, lol!

[racer]

Upgraded rod bearings?

[Superstocker]

Sorry, my bad. Not rod bearings. I meant wrist pin bearings. I went with an "uncaged" wrist pin bearing.

[Riverman]

What do you use as a grease and/or method to assemble the needles?

[perfmarine1]

Sorry, my bad. Not rod bearings. I meant wrist pin bearings. I went with an "uncaged" wrist pin bearing.

You should have stuck with the caged version,the uncaged verson the washer breaks at hi RPM!

[JWTjr.]

You should have stuck with the caged version,the uncaged verson the washer breaks at hi RPM!

I have built many of these with the full floating wristpin bearings and have had no failures. My current 140 turns a 27" OMC cleaver at 7400 rpm with no issues. I'd be interested to see one with this condition.

John

[930turbo]

What do you use as a grease and/or method to assemble the needles?
Take a little wheel bearing grease and put it in the freezer. It thickens up long enough to provide great staying power for assembly.

[200venom]

I use vaseline petroleum jelly.

[Forkin' Crazy]

I have built many of these with the full floating wristpin bearings and have had no failures. My current 140 turns a 27" OMC cleaver at 7400 rpm with no issues. I'd be interested to see one with this condition.

John

Caged bearings are a bit lighter too aren't they? Never weighed them, just assuming. I can't see having no cages being an upgrade.

[powerabout]

hard to believe 7600 is a good rpm to run with stock ports??

[930turbo]

I'm with powerabout, there can't be too much power left at that engine speed. Mine seems to run out of steam at about 6000. I could prop it smaller but I'm certain the boat would slow down. I guess if you are drag racing and need the acceleration more than top end it is justifiable.

[powerabout]

I never ran the original 140's over about 63/400 on light boat as no power after that and crossflows suck a lot of fuel when over reved

[Riverman]

Take a little wheel bearing grease and put it in the freezer. It thickens up long enough to provide great staying power for assembly.Thanks for the tip I can see that working. Or I'll leave it outside, -10 C tonight!

[JWTjr.]

Thanks for the tip I can see that working. Or I'll leave it outside, -10 C tonight!

What's wrong with BRP/OMC Needle Bearing Assembly Grease?

[JWTjr.]

I never ran the original 140's over about 63/400 on light boat as no power after that and crossflows suck a lot of fuel when over reved

True...but the only prop I have that keeps the engine at 6500 is a 30" cleaver, and it doesn't accelerate well with that much pitch.

John

[Riverman]

What's wrong with BRP/OMC Needle Bearing Assembly Grease?

I'm sure I could order it. Just wondering what every else uses as I probably already have it.

[powerabout]

plane old vaseline
it dissolves fast
if you use serious grease you run the risk of rollers skidding

[terry taylor]

-
I've been running a 115/140 conversion on my viper for 2 years now and have turned it up to 7600 rpm for a while. The engine has factory porting & pistons(non-scalloped) and that was as far as I wanted to push it on a lake motor. Now besides sounding great at that rpm(nothing sounds like a v4 crossflow IMHO), I have since propped it to turn ~6700 hopeing to make it live a little longer.

There is nothing special about the engine either; 140 heads, '77 tuner, cut can, 1 5/16" carbs, boyesen, etc. The cylinder porting has not been raised but, everything has been radiused. Including the bubble-back & block where the exhaust re-enters. I have upgraded the wrist pin bearings though. A simple build on a really simple engine that runs great and makes awesome fuel mileage.

I have been thinking about building another powerhead with the 2.6 v6 mods( a la Racer) but this thing is running so well I'm undecided... Good luck with your build and if a v4 crossflow makes you smile at 6000 rpm, you should try 7600, lol!-----------------------I have the same carbs but cannot feed enough fuel air mixture to reach past 62 00 . Is there a secret to this input thanks.

[MattGreen]

What's wrong with BRP/OMC Needle Bearing Assembly Grease?
As John pointed out, the factory bearing grease works fine and melts/dissolves as soon as it sees a bit of oil/heat. FYIW, I haven't put a crossflow together with new wrist pin needles in a few years, but the current looper uncaged wrist pin bearings come packed in a very stiff wax strip that works fantastic to hold the needles together. You just wrap the strip into a circle and slide it into the rod. A dab of the OMC/BOMB grease then holds the washers in place and away you go. They have always been packed this way as far as I know but this wax seemed stiffer than in the past. I assume the CF needles are also packed this way ?

Matt

[Superstocker]

------------------------I have the same carbs but cannot feed enough fuel air mixture to reach past 62 00 . Is there a secret to this input thanks.

I have no secrets to hide. I'd help anyone if I can. I don't think your rpm limit problem is the carb size. What's the sparkplugs look like?

[930turbo]

I've been running a 115/140 conversion on my viper for 2 years now and have turned it up to 7600 rpm for a while. The engine has factory porting & pistons(non-scalloped) and that was as far as I wanted to push it on a lake motor. Now besides sounding great at that rpm(nothing sounds like a v4 crossflow IMHO), I have since propped it to turn ~6700 hopeing to make it live a little longer.

There is nothing special about the engine either; 140 heads, '77 tuner, cut can, 1 5/16" carbs, boyesen, etc. The cylinder porting has not been raised but, everything has been radiused. Including the bubble-back & block where the exhaust re-enters. I have upgraded the wrist pin bearings though. A simple build on a really simple engine that runs great and makes awesome fuel mileage.

I have been thinking about building another powerhead with the 2.6 v6 mods( a la Racer) but this thing is running so well I'm undecided... Good luck with your build and if a v4 crossflow makes you smile at 6000 rpm, you should try 7600, lol!
I applied the "nine pages" to a 140. It is insanely fast. It was however short lived. We stuck it in eight hours. I'm fixing it now as well as building a second motor with the same mods. You would swear it was a v6 when you stabbed it at about 4000 RPMs. It pulled like a tractor.

[Riverman]

------------------------I have the same carbs but cannot feed enough fuel air mixture to reach past 62 00 . Is there a secret to this input thanks.

Pull off a transfer cover and take a picture of the ports. I can pull a 30 past 6200.

[terry taylor]

Pull off a transfer cover and take a picture of the ports. I can pull a 30 past 6200.-----------------------First superstocker, I wasn,t implying that you were thanks. ------------Jeff engines not available at this time, I have ground the radius but not square or height . When the piston is at the bottom of it,s travel , and if I remember the top of same does not completely clear the intake port at the bottom. Is this correct thanks.

[terry taylor]

I have no secrets to hide. I'd help anyone if I can. I don't think your rpm limit problem is the carb size. What's the sparkplugs look like?---------------No such implication intended I use surface gap for high rpm safety and when useing gapped the color is very good for comfort [ with in context] thanks.

[200venom]

Just a thought but could you possibly have a 6200 limit power pack on it? I didn't think any of the V4 crossflows ever had a 6200 pack, but guess it could be possible. The 2.6 GT had one.

[racer]

John I have seen several loopers break the washer on the wrist pin, never ran them in a high rpm flow but I would use the caged ones if I had a choice.

[Forkin' Crazy]

John I have seen several loopers break the washer on the wrist pin, never ran them in a high rpm flow but I would use the caged ones if I had a choice.

Just curious, have you ever checked the difference in weight?

[terry taylor]

Just a thought but could you possibly have a 6200 limit power pack on it? I didn't think any of the V4 crossflows ever had a 6200 pack, but guess it could be possible. The 2.6 GT had one.------------------------Thanks for the input no limiter,

[terry taylor]

Maybe a diff. "tuner" -L-O-L-
(remember me)----------------Yes,and maybe I will try a BOBS , thanks.:leaving:

[evilrude 1]

I was just kidding !
I don't think there is an aftermarket tuner available.
From what I've read (soon to be tried by my self) the orig. tuner/pipe gets cut to 7" in length. This gives a greater area for the exhaust to dump into.(the mid section)
From what I remember my KC13R had a 5 or 6 inch tuner that dumped into the mid (but had exh. snout)
You could also try to find a adaptor/tuner from a 77 140.
I am also going to port my 140 to Al's v6 specs and add finger ports as well as 1 3/8 carbs.

[930turbo]

I was just kidding !
I don't think there is an aftermarket tuner available.
From what I've read (soon to be tried by my self) the orig. tuner/pipe gets cut to 7" in length. This gives a greater area for the exhaust to dump into.(the mid section)
From what I remember my KC13R had a 5 or 6 inch tuner that dumped into the mid (but had exh. snout)
You could also try to find a adaptor/tuner from a 77 140.
I am also going to port my 140 to Al's v6 specs and add finger ports as well as 1 3/8 carbs.
The key to higher revs may be in the exhaust. I made a very minor change to my fishing motor stock 140 and picked up 100-200. I gained another MPH. I'll saw some holes and try again.

[powerabout]

IMHO I think the area to look at is where it goes from the bubble back, then back in to the block

[Superstocker]

I too think the exhaust is a key factor in running these engines at a higher rpm. My thoughts are that the short tuner has the single most effect but, attention to every piece of the exhaust system has the greatest effect. Because I decided not to change the factory cylinder porting, I decided to "clean-up" the exhaust passage way making sure to place emphasis on velocity, not volume. I had photos of everything in my phone but the darn phone went out and lost everything. Whenever I go through the powerhead again or build another, I'll be sure to share.

Because I grew up around & compete in NHRA/IHRA stock/super stock drag racing, I feel at home doing port work, figuring velocity, & improving flow. But I realize that changing port timing is a different animal and has a whole different effect. I still have lots to learn in that area.

[Riverman]

I was told that removing the "bridge" in the exhaust area where it re-enters the block helps a lot. Trouble is, one of the main block drains is in that bridge and it would have to be plugged meaning that the powerhead has to be kept inside in the winter.

[930turbo]

I always thought it was amazing that the factory figured out how to stuff the exhaust back into the same hole in the back of the block. There's not much room there but they got it done. The KR-15 had an additional passage outside the block to route down the leg.

[evilrude 1]

IMHO I think the area to look at is where it goes from the bubble back, then back in to the block


There is a lot of grinding to be done in the lower exhaust chest. the cooling port(bridge) can be ground on quite a bit to increase flow. I've seen it removed and the port welded up. Then an external line was added to the base of the block and to the lower cooling jacket on the exhaust bubble.

All sharp edges can be cleaned up to improve flow but I think this is the bottle neck that hinders making some good power. (IMHO)

[Superstocker]

The bridge in the exhaust chest in my engine is almost completely gone except for the water port at the bottom and it is really thin. The thought did cross my mind to completely remove it but, didn't want to get into having to route external drains. I wanted to keep the build pretty simple and look factory stock externally.

I would really like to see some detailed pics of a KR-15 and what was done different from a production v4 block...

[terry taylor]

I was just kidding !
I don't think there is an aftermarket tuner available.
From what I've read (soon to be tried by my self) the orig. tuner/pipe gets cut to 7" in length. This gives a greater area for the exhaust to dump into.(the mid section)
From what I remember my KC13R had a 5 or 6 inch tuner that dumped into the mid (but had exh. snout)
You could also try to find a adaptor/tuner from a 77 140.
I am also going to port my 140 to Al's v6 specs and add finger ports as well as 1 3/8 carbs.----------------KIDDING--your kidding:)

[200venom]

Here's a pic of the 77 tuner, adapter, cut can, & water tube.254696254697254698

[evilrude 1]

def. more taper in that pipe than my chopped stocker.
Thanks for the pics.
Now if I can only find one !

[terry taylor]

I think given the input which I appreciate thanks, I,m going to settle for what I,ve achieved all things considerd, that is 71.1 gps. 6,000 rpm. although I changed set back from 5 1/2 to 3"via vance plate with lower intake installed[bobs] but run the same 28" cleaver and see what it has to say thanks:leaving:

[Paul Vaillancourt]

Here's a 1978 style cut down
http://i36.photobucket.com/albums/e18/LittleSnakey/IMG_24101.jpg

[930turbo]

Looks very similar to the '77 like that. What do you think about closing up the relief holes? Those seem like they would negate any extraction energies the megaphone could generate.

[terry taylor]

Looks very similar to the '77 like that. What do you think about closing up the relief holes? Those seem like they would negate any extraction energies the megaphone could generate.---------------------I think much past idle they would be non instrumental in the content of negation thanks.:)

[930turbo]

Could be. My past experience with expansion chambers tells me you can have zero leaks or loose the benefits. Of course there's no convergance cone in this application so maybe it's moot

[racer]

Weld up the relief it helps power but does hurt idle if the boat floats low.

[evilrude 1]

you could also just thread in a 3/8 pipe plug in the relief holes and blend it inside the "tuner" (if you cant weld-like me)

[930turbo]

Weld up the relief it helps power but does hurt idle if the boat floats low.
Thanks, I just read this under item VI of the Nine Pages. My motor is so high the cavitation plate is only about three inches under water at rest.

[BajaSvr]

Do the Crossflow 140s like to be ran at those high RPMs rather than the 5500-5800 that omc says to run it at.. I'm running mine at 6200 and am trying to find a bigger wheel to get it down in the operating range.. Should i just let her scream.

[930turbo]

I'm going to try the same thing. I currently run a 28, I just bought a 30 to see if I gain any speed. I'm thinking I'm beyond the powerband @ 6000.

[terry taylor]

Do the Crossflow 140s like to be ran at those high RPMs rather than the 5500-5800 that omc says to run it at.. I'm running mine at 6200 and am trying to find a bigger wheel to get it down in the operating range.. Should i just let her scream.------------------------------------Absolutly not, You are very wise to stay in this area thanks:)

[BajaSvr]

Thanks for the info

[200venom]

ttt for gonefishin485

[akaV153]

Reckon he missed it. Gone fishin I spose.

Anyway, may I offer instead my thanks for the bump.

Do you know if this works:

[flabum1017]

put this on it :eek:

301296

[Umassot50]

put this on it.

[Umassot50]

takes honda reed cages

[gonefishin485]

nah i saw it, just dont have a can and dont have my power head off to cut my downpipe short. BUT if i were to cut my down pipe, how long are those pipes yall are running?

[akaV153]

how long are those pipes yall are running?I'd like to know about this too?

Currently building one. Scalloped block, squared off ports, etc. Boat is a 15' Baja. Hole shot & mid range aren't a problem but I'd like to get a lil more out of it up top. Will cutting the can help?

[6Killer]

Um50, how did the intake work out?

[Umassot50]

Um50, how did the intake work out?

its coming along. the carb arrangement is tricky and im designing some intakes for the carbs. one side the carbs (mikuni super bn) are going to be upside down. this puts the the fuel inlets all in the middle. so the carb fuel inlets will be T'ed together. also allows better access to fuel adjustment screws on all carbs. chokes wont be used. primers instead.

[6Killer]

How proficient are you at tuning pumpers!

[Umassot50]

How proficient are you at tuning pumpers!

unfortunately i have not tuned these carbs(super bn) before. I figured since they are widely used maybe not on boat engines but other areas there should be plently of tuning advice available. any tips?

[6Killer]

Always wanted to tune something with pumpers on it, never had the chance. I suspect that they can be set up to respond just as well as FI if the guy doing the tuning is good at gathering telemetry and making the appropriate changes.

[bruzercomp81]

takes honda reed cages

where do I get one of these?