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JRPM/e-PerformanceMarine
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Discussion Starter #1 (Edited)
I am looking for a solid roller cam similar to the Comp Cams XM288H

Adv. 288 304 @ .050 244 254 .580 .585

With all my input into Cam Quest it is the #1 choice so I would like to try one and see if it gets me where I need to be.

Here is what I got;

BBF 429

.030 (4.390), 3.59 crank, TRW 2366 Flat Tops, Mildly ported ex and cj entry C9 heads with 2.25 in, 1.75ex, the pistons are .007 in the hole and .038 head gaskets. I have a Victor 460 ported to cj specs and it is a Dom flang with a 2" 4150 adapter, with a 850dp sittin on top.

I need this engine to spin a MPD Heritage A impeller to a min of 5600rpms.

I have run the Comp XM 298, it was OK but not enough RPM. I installed the Comp 292H and it was better but not enough rpm eather. I barrowed a XR274R-10 and the mid range pull was real nice but it is not the ticked eather. So I want to try something else. I know this engine will turn the rpm desired. I want to stay with a solid roller.

Thanks
Jim
 

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I am looking for a solid roller cam similar to the Comp Cams XM288H

Adv. 288 304 @ .050 244 254 .580 .585

With all my input into Cam Quest it is the #1 choice so I would like to try one and see if it gets me where I need to be.

Here is what I got;

BBF 429

.030 (4.390), 3.59 crank, TRW 2366 Flat Tops, Mildly ported ex and cj entry C9 heads with 2.25 in, 1.75ex, the pistons are .007 in the hole and .038 head gaskets. I have a Victor 460 ported to cj specs and it is a Dom flang with a 2" 4150 adapter, with a 850dp sittin on top.

I need this engine to spin a MPD Heritage A impeller to a min of 5600rpms.

I have run the Comp XM 298, it was OK but not enough RPM. I installed the Comp 292H and it was better but not enough rpm eather. I barrowed a XR274R-10 and the mid range pull was real nice but it is not the ticked eather. So I want to try something else. I know this engine will turn the rpm desired. I want to stay with a solid roller.

Thanks
Jim
Hey squirt, Call chet Herbert racing cams in chino ca. They will grind what you want or recommend maybe something better. Chet has been racing longer than most have been alive. You might recognize his son Doug. The guy that races top feul. I have used his and only his cams for about thirty years and ALWAYS got what I expected. They do ship. 1-909-393-4597.
 

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Resident Ford Nut
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You are more than likely looking at a custom cam. A roller with those specs will be hard to come by because it is a relatively small cam for a roller. Might want to look for a Hyd. roller.

Here is a Crane Cam you might want to look at, you didn't list your compression ratio:
http://www.cranecams.com/?show=browseParts&lvl=2&prt=5&Vehicle_Type=Auto&Cylinders=8&Engine_Make=FORD-MERCURY&Year=1970&Engine_Size=370-460 C.I.&partNumber=358501&partType=camshaft

I'd look for a cam with a lobe sep of 108* for the impeller rpm range you are looking at.

Just my .02 .......it might not be worth crap. Depends on the day and what time it is ;)

Sleeper CP
Big Inch Ford Lover :)
 

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Hey squirt, on a side note!!! I raced a 429 ford in my Southwind 19ft t/d back in 1980 thru 1982 and spun my ol 429 5800 rpm and went thru the clocks at 92 mph. Not to bad for a boat built almost 30 years ago with a boat that I bought from southwind direct and did ALL the work myself. The boat was picked up bare hull on a trailer. Man do ever miss the ol NJBA races at Bluewater in parker. M
 

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Jim how hard were you turning that Heritage A before? Takes about 775hp(corrected) to turn that impeller to 5800, I dont have my Dyno sheet Handy or I'd tell you what power is for 5600...
 

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Hey guys! I don't want to start a pissing match or ruffle any feathers by pissing in someones cheerios but jet boats are not only about the numbers on a dyno as much as the underwater hardware and how efficient the hull works with what you have. A single carb 500 H/P motor can push a 400 pound hull into the 80s if all is set up right. You may (and probably will) call bullshlitz and that is fine but I have done it and I know it and thats all that matters. IMLOA Mark
 

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OH and by the way I think I should change my avitar. When I told myself I was done with hot boats I think the wrong head was listening. I'll get it up soon- The avatar!!! Mark
 

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JRPM/e-PerformanceMarine
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Discussion Starter #10
Jim how hard were you turning that Heritage A before? Takes about 775hp(corrected) to turn that impeller to 5800, I dont have my Dyno sheet Handy or I'd tell you what power is for 5600...
The best I have turned with this 429 is 5300 -5400 with a constant 5250rpms.
 

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JRPM/e-PerformanceMarine
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Discussion Starter #11
You are more than likely looking at a custom cam. A roller with those specs will be hard to come by because it is a relatively small cam for a roller. Might want to look for a Hyd. roller.

Here is a Crane Cam you might want to look at, you didn't list your compression ratio:
http://www.cranecams.com/?show=browseParts&lvl=2&prt=5&Vehicle_Type=Auto&Cylinders=8&Engine_Make=FORD-MERCURY&Year=1970&Engine_Size=370-460 C.I.&partNumber=358501&partType=camshaft

I'd look for a cam with a lobe sep of 108* for the impeller rpm range you are looking at.

Sleeper CP
Big Inch Ford Lover :)
That one is very similar to the xr274 I am barrowing from Brunt Racing.

Just my .02 .......it might not be worth crap. Depends on the day and what time it is ;)
.02 is worth .02 and any thoughts are always helpfull.
 

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JRPM/e-PerformanceMarine
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Discussion Starter #12
Hey guys! I don't want to start a pissing match or ruffle any feathers by pissing in someones cheerios but jet boats are not only about the numbers on a dyno as much as the underwater hardware and how efficient the hull works with what you have. A single carb 500 H/P motor can push a 400 pound hull into the 80s if all is set up right. You may (and probably will) call bullshlitz and that is fine but I have done it and I know it and thats all that matters. IMLOA Mark
Isn't that way they have them.
 

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It's what we do
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I agree that you will have a hard time turning that impeller 5600 with that combination. Cut the impeller to an AB... my .02:D
 

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cut the impeller to a b-cut,other than that good luck:)hand:)hand:D
exactly.

all the underwater hardware tuning in the world isn't going to get him the rpm he's after with that motor combo and that impeller.

he was targeting a specific rpm level and didnt mention speed.
 

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exactly.

all the underwater hardware tuning in the world isn't going to get him the rpm he's after with that motor combo and that impeller.

he was targeting a specific rpm level and didnt mention speed.
Cyclone, So what you are telling me is that a boat that plows thru the water and has a loader that is cutting really deep wont make a bit of difference as long as the motor has a BIG cam and 700 h/p numbers on a dyno. For what its worth an iron 429-460 ford will make 700 h/p as long as the person building it has more brains than money. If you think I'm wrong just go back to who clicked the first 7 second pass in a pro stock car and then look at the motor that did it and notice the lack of aluminum. M
 

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Cyclone, So what you are telling me is that a boat that plows thru the water and has a loader that is cutting really deep wont make a bit of difference as long as the motor has a BIG cam and 700 h/p numbers on a dyno. For what its worth an iron 429-460 ford will make 700 h/p as long as the person building it has more brains than money. If you think I'm wrong just go back to who clicked the first 7 second pass in a pro stock car and then look at the motor that did it and notice the lack of aluminum. M
you said it I didnt.

I'll say it again. No underwater hardware tuning is going to get his A impeller spinning the rpm he wants with his engine combo. I know what kind of power it takes to turn one of Jack's blueprinted impellers and Jim's got a pretty large impeller in his pump.
 

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you said it I didnt.

I'll say it again. No underwater hardware tuning is going to get his A impeller spinning the rpm he wants with his engine combo. I know what kind of power it takes to turn one of Jack's blueprinted impellers and Jim's got a pretty large impeller in his pump.
i WILL BET YOU EVERY THING I OWN I CAN MAKE THAT BOAT SEE 6K. Now before you say okay have you ever heard of closing up the intake from 11 inches to 9 inches. RPM go thru the roof but unless the boat gets proper lift and low drag it is all a waste of time.
 

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Spiral out
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i WILL BET YOU EVERY THING I OWN I CAN MAKE THAT BOAT SEE 6K. Now before you say okay have you ever heard of closing up the intake from 11 inches to 9 inches. RPM go thru the roof but unless the boat gets proper lift and low drag it is all a waste of time.
Fully loaded "A" impeller to 6000rpm........do that and he'll be out front the whole race.:)grn (not so sure about the turning though:p)
 

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Resident Ford Nut
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i WILL BET YOU EVERY THING I OWN I CAN MAKE THAT BOAT SEE 6K. Now before you say okay have you ever heard of closing up the intake from 11 inches to 9 inches. RPM go thru the roof but unless the boat gets proper lift and low drag it is all a waste of time.
So if the rpm goes way up the speed will always go up ? :)bulb

Sleeper CP :D
 
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