Setback Pumps

[Bense468]

All you guys out there that are set back in in southern cali, who cut your setbacks. I mean who plugged the bottom? Is this generally a guy that does bottoms like IE Jeff Bennet or more a pump guy like Jack from MPD? I know Jack does not like to cut where the transome meets the bottom and has the half set back. Which is nice. I like the transom adapters but you can't run a pop off whith those right? Also do any of you know where you can purchase a pop off valve and some cable steering?

[RiverDave]

Bense 468, is this a lake boat? If so you don't want to run a "pop off." Most of them have to be manually reset after they release. Have you looked into a "jet-a-away?"
RD <-- Not to shabby for a prop guy eh? LOL http://free.***boat.net/ubb/biggrin.gif

[HBjet]

Not too shabby at all RD!
Bense, buy a Jet-A-Way from HI TECH performance before a pop-off valve. Also, before you go to a setback, have some shoe work done, like a back cut to give the tail of the boat a little more lift. What are you trying to do with a setback and a pop off, just curious.
HBjet

[Hallett19]

what the hell is a pop off and a jet a way ?

[HBjet]

Originally posted by Hallett19:
what the hell is a pop off and a jet a way ?
http://free.***boat.net/gallery/Raceboat_Arenas/Drag_Boats/tomp5.JPG
The black cyclinder looking thing on top of the hand hole cover = Pop Off Valve. It releases the pressure from the bowl when your at high RPM's. (Like drag boat racing)
http://www.hi-techperformance.com/images/IMAGE12.JPG
http://www.hi-techperformance.com/images/JETAWA~1.JPG
Here is the Jet-A-Way, Read Up!
HBjet

[Bense468]

Yeah I already know about the Jet a way. I plan on running one. I am going to build a NJBA boat and was just wondering where to get the pop off. Yeah they have to be manually reset but I also think they have to be manually set off. Meaning you flip a switch to release the pressure. They might run pressure solonoids that do it without a switch. Anyway I can get by without the pop off but I was just curious where you buy one. The most important question is the plug for the intake where do you usually get these done at? I am trying to find more info on the Banderlog data system is this just like the edelbrock quick data? I know what the quick data does but what exactly does the banderlog thing do? How much is it? JUst getting prepared thats all

[Bense468]

Oh and randy I am sure you know this already but the jet-a-way does not take the place of a pop off. They are two different things completly. The jet-a-way is not going to release the pressure in the intake so that you don't marble. If you were to let off. You are right though the jet-a-way is a more important object at first and I plan on getting one. But I would have to plan my setback on how fast I want to go because once you get to a point you need to run a pop off and with the MPD transom adapter I believe you can't.

[572Daytona]

Bense, as I understand it the Banderlog system is a launch controller which aids your starts by gradually ramping up your RPM's at the start to avoid the cavitation that you would get if you were to just smash the pedal off of the line. It is programmable in that you can pick what RPM to limit your motor to at various time increments. For more info go to http://www.banderlog.com There is also a message board over there that caters to jetters and there are several members there that participate in NJBA and should be able to answer whatever questions that you have.

[Oldsquirt]

Bense, the Banderlog device is NOT a data acquisition unit. It is a programable rev limiter designed only to be used during the launch phase of a run. Where a lot of guys run a single- or dual-stage rev limiter, the Banderlog allows you to build a rev limit CURVE to suit your engine/hull/pump combo. Your confusion about it being a data acquisition unit probably stems from the fact that the guys use a laptop to program it.
Go to the races in May and talk to the guys in the jet boat pits. Lots are using them this year. Last year Keith Zellmer was using the prototype in his Risky Business boat. Jim Lee was on his crew and is responsible for designing it.
Here is the direct link for more info: http://www.banderlog.com/launchController/launchController.html
[This message has been edited by OLDSQUIRT (edited April 19, 2002).]

[Bense468]

Thanks guys thats what I thought. I talked to the Andersons in April at ming. I thought it did launch control but I was not sure. I thought maybe it was like the quick data with a launch control built in. I was not sure. I will be up there in May and I will talk to more people about this. Are any of you guys going up there May 4th?

[HBjet]

Originally posted by Bense468:
But I would have to plan my setback on how fast I want to go because once you get to a point you need to run a pop off and with the MPD transom adapter I believe you can't.
BTW, MPD makes there stuff custom to the boat. There isn't a set adapter used on every boat. If your hand hole on the pump is half way in and half way out of the transom, you could cut out the top of the transom and install the pop off.
http://free.***boat.net/gallery/Gearhead_Garage/Other_Equipment/popoff.JPG
See the above photo, and how the hull is cut for the pop off.
BTW, what hull are you going to run for racing? What class are you going to run in?
HBjet

[RR1/ 001]

From what I under stand the Jet-A-Way does the same thing by letting the impeller free wheel ( release the pressure) in the in take, if you have lost power to the motor (it`s stoped turning) you shouldnt marble.

[Kwicherbichen]

Bense468 the pump set up in this picture belongs to Tom Papp (it's his race boat). I would call him and ask him what you need to do to make all those things you want happen.
His address is:
Tom Papp Racing
1640 Industrial Avenue
Norco, CA 92860
(909)734-4606
http://www.tompappracing.com
Tom is in the shop by 7am and usually stays past 6pm.
http://free.***boat.net/gallery/Raceboat_Arenas/Drag_Boats/tomp5.JPG

[flat broke]

Bense,
First and foremost know how fast you are going to want to ultimately run. Odds are that most of us wouldn't see speeds required for a pop off. The Jetaway however, anybody could use that, and safety concerns aside, its damn handy to have when you need to run the motor in the pits. Just disengage and fire her up.
Now as far as the saftey concerns between the two, yes if you have a jet a way installed your impeller will freewheel, but if you are running up in the 130s or so, or just depending on how much bite you have dialed into your shoe, and the characteristics of your hull, even though the impller freewheels, you could still build intake pressure and jack the back of the boat up; this is when you want to look at a pop off. My guess is is this is less of an issue by quite a bit if you are running a v vs an air entrapment hull.
On your setback, call Jack when you're ready to do the work, but know in advance that if you are going to get the hand hole totally clear of the transom, you are almost garanteed to have to cut the hull on the bottom at the transom and leave no support back there.
My advice, find the guys that are running in the bracket or class you plan on shooting for at the May races, then talk to them (99% would tell you more than you need to know) and check out their setups. Focus on the guys that are running the same hull you plan to campaign.
Good luck,
Chris www.liquidaddiction.net (http://www.liquidaddiction.net)

[Bense468]

I am in no big hurry. I am just thinking right now. Randy if I did this I would probably run a 10 second class with a CP gullwing. I know I really don't need the pop off and more then likly am not going to run one. I will run the jet a way though. I was just trying to get ideas becasue if I did a set back without cutting where the transom meets the bottom you have more strength. I like that setup but I was thinking if for some reason I ever decided to drop to the 9's which I doubt I will because I want this to be a river boat also then I did not want to screw myself by having to re-cut everything if I wanted to add the pop off. Thanks for clearing things up guys. Any of you going to be at Ming on May 4th?

[Johnwithjm]

Originally posted by HBjet:
BTW, MPD makes there stuff custom to the boat. There isn't a set adapter used on every boat. If your hand hole on the pump is half way in and half way out of the transom, you could cut out the top of the transom and install the pop off.
http://free.***boat.net/gallery/Gearhead_Garage/Other_Equipment/popoff.JPG
See the above photo, and how the hull is cut for the pop off.
BTW, what hull are you going to run for racing? What class are you going to run in?
HBjet Bense468 The picture of this boat is mine. I did all the cutting and mounting myself. It is very easy to do. A blow off valve work better than a Jet-A-Way in my opinion I have had good luck with mine. We will be at the next race so come by and say hello. Good luck John Boat #516

[Duane HTP]

I thought by some of the posts here, I might need to shed a little light on how the JETAWAY works. I don't want to start a pissing match here, so let me say up front, pop-offs are a good device. So is the JETAWAY. They work in different ways to achieve the same goal; Less intake pressure during deacceleration. The pop off valve lets the pressure out of the top of the intake when it reaches a preset pressure. The JETAWAY lets the pressure out by allowing the impeller to keep turning, which in some cases still maintanes some degree of steering. When the intake has built up enough pressure from a dead engine or whatever, to set the pop off valve off, the upward thrust has already been applied to the boat bottom to some extent. But when the same thing happens with a JETAWAY, it works instantly, before there is any pressure exerting an upward force on the boat. Probably most important, is the fact that the JETAWAY works EVERY time. In many cases over the years, we have had customers who have run both the JETAWAY and the POP-OFF at the same time. I suppose this is the safest. But when the two are run together, many times the POP-OFF will not ever see enough pressure to pop it off. They both have their advantages and disadvantages, and both do a good job, just wanted to clear up how they work a little. If you have questions, Ask them. I'll try to answer them. Duane HTP

[HBjet]

Duane, thanks for posting. I really like the Jet-A-Way device. I was wondering, when would you recommend someone to run one on a lake boat? You said there are some disadvantages, what would those be? Having to move the motor forward to allow the space? Oh, when using the Jet-A-Way, and you have it disengaged, is there anyway it can accidently re-engage when the motor is running? Thanks
HBjet

[Duane HTP]

Yes, the 4 1/4" is a problem in some boats. Sometimes we install them with only one u-joint and they work just fine. In that case you only move the engine forward 1 1/2". No, it's physically impossible for it to jump back in gear. Duane HTP

[Duane HTP]

Sorry, I didn't answer all of your question. I would recomend a JETAWAY at about 65 mph in a V-Bottom, and at about 80 mph in a tunnel hull, or when ever you might want to run your engine with the boat out of the water. They're handy for testing, tuning, and warming your engine.

[Taylorman]

Is it bad to run boat out of the water with a garden hose. Why would you need a jet away?

[Johnwithjm]

Duane HTP I did not mean to bag on the jetaway set up in my case I have had good luck with my valve. The jetaway works well also

[HBjet]

Duane, last question, how much are you selling the Jet-A-Way?
HBjet

[Duane HTP]

List Price on the JETAWAY is $1,440.00. The current Racer Net Price is $1132.00. I think I still have about 12 of them left at this price. I have started the process of making 50 more, but the price is going to go up considerably on this batch. How much? I don't know yet, but just about everything is higher so far. I've held the price on the last three runs of them, but this time it's more than I can absorb. There's really no mark up in them. Daune HTP

[jeff-in-ky]

My boat has the ratchet release (I think that is the corect term) from Don's pump service. It seems to work well also, you just can't disconnect it from the driveline like you can the jet-a-way. Does the jet-a-way make the same annoying noise when you shut the motor off like Don's does.
JB

[Duane HTP]

The JETAWAY has four clutch teeth instead of three, so the gap between the teeth is not as far, and the case is thicker. This dampens the noise somewhat. However, it does make some noise of the same type. That let's you know it is working properly. Duane HTP