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Caribbean19'
01-30-2001, 08:44 PM
I need more holeshot! I have a 1991 19' Caribbean with a Berkely pump, place diverter, A impeller, and stock 333 HP 454, and thru transom exhaust. The carb is a 650 Holley with vacuum secondaries (and I have experimented with the spring kit--not much difference). I have a low profile, single plane, spread bore pattern intake manifold matched to a standard pattern carb with an adapter. The timing is advanced slightly to improve throttle response. The jet pump has never been blue-printed; it has no leaks and no slippage. I presently top out at around 55-60 mph (not GPS) at around 4700 rpm. I do not mind losing some top speed for an improvement in holeshot. My mechanic says I should be able to pull up two single-ski skiers with not too much problem--but the boat has a tough time popping out one skier. I don't want to spend very much money--I want to stay away from a cam change etc. Would a dual plane spread bore intake manifold matched up to a 650-700 Holley double pumper (with matching spread bore pattern) do the trick? Or do I need a different impeller? Or both? Help!

SPECTRABRENT
01-31-2001, 10:14 AM
I would do the following 3 things to your pump.
1) Blueprint your pump
2) For hloie shot got to bigger impeller AA
3) Install DPS impeller loader
If you do the above things to your pump you will have a hole shot.
Call Jim Brock @ (818) 890-1687 he will steer you in right direction.
SpectraBrent

Caribbean19'
01-31-2001, 04:53 PM
Thanks SpetraBrent--I'll give him a call.

Squirtcha?
01-31-2001, 08:04 PM
I think I'd check your setup over carefully first. You should be able to pop 3 skiers out of the water with your current setup. Check you carb and make sure that when you hit the throttle you're getting a good healthy shot of gas in the primary bores. You don't even have to start the boat for this one. If you're primary squirters aren't working check the accelerator pump diaphragm and make sure it isn't ripped. Check to make sure the squirters themselves aren't plugged. You may want to consider changing them for a larger size but the stock size is usually fine for a stock motor such as yours. I've got an 18.5 footer with a stock 460 Ford and it'll rip your arms off on a ski take off (if you've a mind to). I wouldn't change a thing without checking everything you currently have to make sure it's working properly!

ChetC
02-01-2001, 10:03 AM
You didnt say in your boat description if you have any kind of intake grate the boat. Well worth the 65 or so bucks and will help your holeshot for sure. Good luck.

Squirtcha?
02-01-2001, 02:17 PM
Carribean
You didn't say what your motor is doing when you punch it. Is it missing? Is it dogging out? Running smooth and just no power? With all due respect, I wouldn't start rebuilding pumps that don't need it, and I quote you "it has no leaks and no slippage". I'd hate to see you throw your money away on shotgun repairs. Hell when I first got my boat the pump was shot and it still pulled a 225 lb skiier (me) up with no problems. If you want and excuse to modify just do what everyone else does (cause they wanna) If you just wanna be able to get a skier out of the hole, check your current setup. Nobody is going say that my stock Ford BB has more power than a stock Chevy BB are they?

MoJetBoPar
02-01-2001, 06:27 PM
I'm with ya Squirtcha?. Rule out the lowbuck stuff first. Process of elimination. Do you have a healthy accelerator pump squirt? Hook up your timing light and make sure the mechanical advance weights are working and haven't rusted themselves in place. It happened to me on a HEI Chevy. Maybe get a fuel pressure gauge too.

MoJetBoPar
02-01-2001, 06:30 PM
Originally posted by MoJetBoPar:
I'm with ya Squirtcha?. Rule out the lowbuck stuff first. Process of elimination. Do you have a healthy accelerator pump squirt? Hook up your timing light and make sure the mechanical advance weights are working and haven't rusted themselves in place. It happened to me on a HEI Chevy. Maybe get a fuel pressure gauge too.
I don't care for single-planes much on a heavy boat. They require more pump shot to fill the hole. Too easy to create a big sag at low-end

Caribbean19'
02-01-2001, 07:09 PM
Squirtcha,
Thanks for the help. I'd love to pull two or three skiers up! I'll check into what you suggested--it makes sense. When I punch the motor it goes--but with hesitation under a load like it is hungry for air.
Thanks,
Caribbean 19'
[This message has been edited by Caribbean19' (edited February 01, 2001).]

Caribbean19'
02-01-2001, 07:14 PM
ChetC-I just have the stock grate--nothing special. I will look into something better. Thanks!

Caribbean19'
02-01-2001, 07:16 PM
MoJetBoPar:
Your advice sounds good--I'll check into it. Thanks!

Squirtcha?
02-01-2001, 09:09 PM
MoJetBoPar
I'm running a single plane intake on my 460. Edelbrock Torker I. It's not my preference but it was on the boat when I bought it and seems to work o.k. at least for now. Even with a less than perfect intake I still get an awesome holeshot, especially with the diverter pointed to hell. BAM I'm on plane!

jim lee
02-01-2001, 10:45 PM
Wait, I'm missing a bit here. Is the motor not running well? Or, is it running fine and the pump just isn't doing its job?
-jim lee

MoJetBoPar
02-02-2001, 10:34 AM
Originally posted by Squirtcha?:
MoJetBoPar
I'm running a single plane intake on my 460. Edelbrock Torker I. It's not my preference but it was on the boat when I bought it and seems to work o.k. at least for now. Even with a less than perfect intake I still get an awesome holeshot, especially with the diverter pointed to hell. BAM I'm on plane!
Sorry Squirtcha?!
That single-plane comment was a generalization and towards smallblocks more in particularly. Big blocks, being torque monsters, aren't usually as vulnerable to sensitive volume flow but I had no idea of how much his hull weighs.

Squirtcha?
02-02-2001, 01:51 PM
No problemo MoJetBoPar. In fact I'm going to be ordering my Weiand Stealth here in the next couple days. Like I said the Torker isn't my choice, it was on there. Especially the old Torker I. I hear the II is bettter but I'll never know.

Caribbean19'
02-02-2001, 03:50 PM
Originally posted by jim lee:
Wait, I'm missing a bit here. Is the motor not running well? Or, is it running fine and the pump just isn't doing its job?
-jim lee
Jim Lee- the engine "seems" fine and the pump "seems" fine; in other words there is no obvious problem with either not running properly. The engine/pump combo just do not seem to perform like they should, as if the boat is underpowered and unable to pop up skiers easily. Other jet boaters with my similar set-up have a much better/easier time pulling skiers up. What do you think? Thanks for your input!

jim lee
02-02-2001, 04:22 PM
If the engine is spinning Max RPM (Runing fine) and the boat ain't pullin'. The first thing I'd do would be to look at the leading edge of your impeller. Get a flashlight, crawl under and give it a good look over. The leading edges should be sharp with no nicks and stuff. From what I've picked up from those that actually know what heir talking about. (I'm just a parrot) The leading edge is what gives you your hole shot. If its dull and niked up, your not going to get a very interesing hole shot.
Now, if the engine isn't hitting max RPM out of the hole, you have other troubles.
A) The engine isn't running right.
B) The impeller is too large of a cut to let the engine REV where it likes it.
P.S. You must remove the trailer from the bottom of the boat before resuming definitive testing. :-)
I hope this helps,
Good luck!
-jim lee
[This message has been edited by jim lee (edited February 02, 2001).]

DougB
02-02-2001, 05:20 PM
Awright you guys! Back home to RealJetBoats where ya belong!!!!!

GlastronGuy
02-02-2001, 05:48 PM
Originally posted by DougB:
Awright you guys! Back home to RealJetBoats where ya belong!!!!!
LOL http://free.***boat.net/ubb/wink.gif

spectras only
02-02-2001, 06:09 PM
Back in 1976, my Spectra 20 [3000 pound]came with the 460 Ford [Harman Marinized], they put the 429 SCJ cast iron dual plane manifolds on all their engines.These manifolds were depleted by the 460 OMC KING COBRA applications.All of the BBF came with either Hoolley 780 or 830 cfm carbs.Big Fords like big carbs.A marine cam with 502 lift and around 220 duration at 0.50 lift will give you the bottom and you need to pull multiple skiers.I had no problem pulling 3 skiers on two skis with this setup and two slalom skier on single skis.You can go to the Ford Motorsport 443 cam, about 566 lift and 230 duration ,that will give you even more power.My friends 19 Spectra has this combination ,we clocked the speed at 72MPH at sealevel w/GPS.With the placediverter turned down we just snap 3 skier up no time at all.I suspect carburation setup problem here.Check your power valve, make sure it's open up fast enough.your primary jets should be min 72, secondaries should be 85 with a 780 Holley.Primaries should be 76,secondaries should be 94 with a 830 Holley.Dont bother with double pumpers.Let us know how you progress.

Caribbean19'
02-04-2001, 08:20 PM
Spectras Only--Thanks for the advice--I'll check it out.

powrboat
03-19-2001, 03:49 AM
Originally posted by Caribbean19':
[B]I need more holeshot! I have a 1991 19' Caribbean with a Berkely pump, place diverter, A impeller, and stock 333 HP 454, and thru transom exhaust. The carb is a 650 Holley with vacuum secondaries (and I have experimented with the spring kit--not much difference). I have a low profile, single plane, spread bore pattern intake manifold matched to a standard pattern carb with an adapter. The timing is advanced slightly to improve throttle response. The jet pump has never been blue-printed; it has no leaks and no slippage. I presently top out at around 55-60 mph (not GPS) at around 4700 rpm. I do not mind losing some top speed for an improvement in holeshot. My mechanic says I should be able to pull up two single-ski skiers with not too much problem--but the boat has a tough time popping out one skier. I don't want to spend very much money--I want to stay away from a cam change etc. Would a dual plane spread bore intake manifold matched up to a 650-700 Holley double pumper (with matching spread bore pattern) do the trick? Or do I need a ]different impeller? Or both? Help![/B

powrboat
03-19-2001, 03:53 AM
It looks like you have a lot of differing opinions here. I wouldn't know which way to go if I were you I would contact Don's Pump Service at Donspumpservice.com snd give him all the specs. He'll know what you need to do. Good luck!]