Winter project choice.

[kachina_labala]

Decisions?
I have 2 choices to go with for my winter project. First off the specs
1995 Kachina 22Â’
MPD prepped A1.5 dominator pump
BBC Gen V 4 bolt stock bottom
Edelbrock dual quads with Edelbrock manifold
Rectangle port heads
Lightning headers.
Comp cams extreme marine cam 11-232-3 lift .505 .515 dur 262 268
According to desktop dyno 414hp at 5000 tq 502 at 3500
Im getting 54 MPH at 4600rpm. 402 HP according to JPC (pretty close)
Option 1: I already own a Nitrous works dual quad plate system. I also have an offenhauser dual quad manifold. On The Edelbrock manifold the carbs are too close together to put on the NOS plates so I would have to change the manifold. 125hp shot is the minimum for the kit. This cost me less as I already own all of the parts.
Option 2: Sell the Nitro, sell the manifold and put in a different cam. I kind of like the comp cams extreme marine hyd roller 11-451-8 lift .547 .547 dur 284 290 (but im open to suggestions).This would put my hp at 521 @ 5500 tq 537 @ 4500 according to desk top dyno The kit and extras to do it right would $1000+ and Im supposed to be conservative with my money right now. But Â…..I am a jet boater.
I donÂ’t think it would be a good idea to do both on a stock lower half. Would be fun ..wile it lasted. :cry:
Any thoughts appreciated.
Matthew

[SmokinLowriderSS]

That engine is fairly young, and the stock bottom of a BBC is pretty darned strong. Weakest spot IMO is the knurled 3/8" rod bolts.
Put the nitrous on it. Then, next year, rebuild it, replace the rod bolts with ARP,s, stud the mains & heads with ARP's, and cam it. The 414 HP Chevy ought to survive the occasional trip to 540 on it's bottom end IMO with no issues this coming year.
If the current rod bolts are bigger than 3/8"ers, I wouldn't even replace them. If they are 7/16", those are solid, damn solid.

[kachina_labala]

Thanks for the reply. Ive done a mock up of the nitro in the boat and it looks good. I even have a great place to hide the bottle. Funny button here I come.
Matthew

[kachina_labala]

Im now looking for a nitrous activation switch. I thought I at one time saw one in the end of a fwd/reverse clamshell control handle. Any other cool ideas/ links to switches for sale.

[Squirtcha?]

Option 1: I already own a Nitrous works dual quad plate system. I also have an offenhauser dual quad manifold. On The Edelbrock manifold the carbs are too close together to put on the NOS plates so I would have to change the manifold.
Matthew
Have you considered mounting the nitrous plates sideways? I had to do it with mine for clearance sake and they work fine that way.
Mine are setup so that the spraybars go side to side instead of front to back. I've sprayed a bunch of nitrous on this setup and haven't had any problems with it.
Edelbrock's tech support cautioned me that they hadn't tried one that way and they couldn't tell me whether or not it would work. I figured that since it was spraying into a bigass'd plenum before getting drawn into the carbs.........what possible difference it could make. In addition, if you remove the plenum section and look into the runners, they're so symetrical that it doesn't appear there would be any difference even without the plenum (front to back vs. side to side).
Apparently it doesn't make a whole lot of difference, since it's worked fine this way for two seasons and lots of bottles.
Just trying to offer some options.
http://www.homestead.com/jetboat/tunnelplumb.jpg

[kachina_labala]

did you have to modify the plates? I didnt think that the mounting holes were a true square pattern? even with the new manifold I would have to stagger the plates with carb spacers to get the hoses to clear. Im not sure what the manufatrurer was thinking when they made this kit. Im concerned about the 2" difference in the height if the plates from the intake causing the nitro to get to 1/2 the cylinders first. I wll either have to get some elbows that go right at the plate or try and mount them sideways. Here is the new manifold and carbs on the top. notice the blue hose fittings are staggered.
http://www.hotboatpics.com/pics/showphoto.php?photo=36859&papass=&sort=1&thecat=http://www.hotboatpics.com/pics/data/500/4896Nitro1.jpg

[IMPATIENT 1]

Have you considered mounting the nitrous plates sideways? I had to do it with mine for clearance sake and they work fine that way.
Mine are setup so that the spraybars go side to side instead of front to back. I've sprayed a bunch of nitrous on this setup and haven't had any problems with it.
Edelbrock's tech support cautioned me that they hadn't tried one that way and they couldn't tell me whether or not it would work. I figured that since it was spraying into a bigass'd plenum before getting drawn into the carbs.........what possible difference it could make. In addition, if you remove the plenum section and look into the runners, they're so symetrical that it doesn't appear there would be any difference even without the plenum (front to back vs. side to side).
Apparently it doesn't make a whole lot of difference, since it's worked fine this way for two seasons and lots of bottles.
Just trying to offer some options.
http://www.homestead.com/jetboat/tunnelplumb.jpg
that's a sick set-up squircha, how much hp are you runnin on the nitrous alone.

[kachina_labala]

Squirtcha,
I noticed that your carbs sit sideways and mine are inline. After a little research Ive been told my nitrous setup is for a tunnelram set up like yours where the carbs sit sideways.Thus the spray tubes would be exactally the way you have yours installed. I was told that I need to get different plates. Damn! :cry: I am having a hard time even finding plates that have the ports on the side like I need and they are $$. Any ideas anyone?
Help
Matthew

[Squirtcha?]

did you have to modify the plates? I didnt
think that the mounting holes were a true square pattern? even with
the new manifold I would have to stagger the plates with carb spacers
to get the hoses to clear. Im not sure what the manufatrurer was
thinking when they made this kit. Im concerned about the 2" difference
in the height if the plates from the intake causing the nitro to get to
1/2 the cylinders first. I wll either have to get some elbows that go
right at the plate or try and mount them sideways. Here is the new
manifold and carbs on the top. notice the blue hose fittings are staggered.
http://www.hotboatpics.com/pics/showphoto.php?photo=36859&papass=&sort=1&thecat=[/IMhttp://www.hotboatpics.com/pics/data/500/4896Nitro1.jpg
Did not have to modify the plates.
I'm thinking the holes are square and the plates will fit on
either way.
I am running 1" spacers so every thing will clear.
I checked mine by mocking it up every whichway before installing
the thing, and if I remember right it would've worked with the
nitrous plates sideways, even if my carbs were installed inline.
My kit was originally a single plate system good for 100 hp max.
I purchased and installed a second plate and jetted each one for
50 hp. Still a 100 hp kit the way I'm running it now.
I could take it up to 200 since each plate will pass up to 100 hp
each, but I'd have to get bigger solenoids and then start messing
with ignition boxes (which I hate by the way), retard boxes etc.
It's just a little 100 hp bump good for about 6-7 mph and 400 rpm.
Changes my boat from upper 70s to mid 80s.
Squirtcha,
I noticed that your carbs sit sideways and mine are inline. After a little research Ive been told my nitrous setup is for a tunnelram set up like yours where the carbs sit sideways.Thus the spray tubes would be exactally the way you have yours installed. I was told that I need to get different plates. Damn! :cry: I am having a hard time even finding plates that have the ports on the side like I need and they are $$. Any ideas anyone?
Help
Matthew
That doesn't sound right to me. I'm thinking the plates you have
would work o.k. turned sideways even with the carbs mounted
inline. Remember I said the nitrous techs at Edelbrock said mine
wouldn't work either? It's difficult to say without being able to see
it, but it doesn't seem like it would make all that much difference.
I do have a little more room for error due to the big plenum on my
tunnelram as opposed to your quad four intake (basically without
a plenum). In my mind (feeble little mind) its seems that as long as
the spray bars are positioned in such a way to spray evenly into all
eight runners of the intake, you should be good to go.
The other thing you could do is mount your carbs sideways like mine.
I only paid $100 for my linkage setup from Good Vibrations (http://www.goodvibesracing.com/Linkage%20Kits.htm).
I home fabbed everything else to make the change.

[jamessampica]

If my eyes aren't lying to me those are not holley carb's so that might be the difference Dan. I might be way off track here since i'm a blower man.But those are not HOLLEY carb's like your's SQUIRTCHA.Will this make a difference's?Just my .02 cent's!!!
Oh yes i have to ask you SQUIRTCHA. Is your boat fixed yet?
Well i've got to get back working on my HOT ROD!!!!!!!!!LATER!!!!!!
JIM S

[Squirtcha?]

If my eyes aren't lying to me those are not holley carb's so that might be the difference Dan. I might be way off track here since i'm a blower man.But those are not HOLLEY carb's like your's SQUIRTCHA.Will this make a difference's?Just my .02 cent's!!!
Oh yes i have to ask you SQUIRTCHA. Is your boat fixed yet?
Well i've got to get back working on my HOT ROD!!!!!!!!!LATER!!!!!!
JIM S
Most the nitrous companies out there make the same kits/plates.
They're either made for a Dominator, or a standard Holley pattern, or a
spreadbore flange. None of these companies stipulate what carbs
are used whether they're Carters, Holleys, Edelbrocks, Demons, or
even Predators. I guess as long as they have the proper flange,
you're good to go.
I guess you couldn't mount any kind of vacuum secondary carb,
or spreadbore sideways though eh? That would be a problem.
And no I haven't done anything with the boat. This weekend though
for sure.
Dan

[kachina_labala]

Dan,
Thank you for you help. The hole pattern in the NOS plate is 5.625 X 5.125. I was hoping to be able to turn the plate and redrill but with the plates shape I would end up with 1/2 holes. They are edelbrock carbs if it makes a difference. I was thinking of coming up with 1/2 inch spacers to stagger the plates for hose clearence. Maybe 1/2 inch is a small enough difference to not matter.

[Squirtcha?]

Dan,
Thank you for you help. The hole pattern in the NOS plate is 5.625 X 5.125. I was hoping to be able to turn the plate and redrill but with the plates shape I would end up with 1/2 holes. They are edelbrock carbs if it makes a difference. I was thinking of coming up with 1/2 inch spacers to stagger the plates for hose clearence. Maybe 1/2 inch is a small enough difference to not matter.
Hmmn guess they did it that way for a reason eh? I coulda swore that I had test fitted em that way. Must not have though.
Sorry that's not going to work out for ya.
What about plumbing the nitrous with hardline? It takes up a lot less room than the stainless flexible lines, and you can take tighter corners/bends with it.
Anyway. If you don't mind...........let me know what you end up doing and how it works out for ya?
Dan

[Taylorman]

Im now looking for a nitrous activation switch. I thought I at one time saw one in the end of a fwd/reverse clamshell control handle. Any other cool ideas/ links to switches for sale.
Check out http://www.jimmy-jams.com/. Click on the activation switches link.

[kachina_labala]

These guys have bunches of AN fittings in stock. They were very helpful
HP Hose (http://hphose.com/)