Reply With QuoteJust get a 20' cruiser and be done with it. My cruiser has 425 HP and goes 68 all day long spinning an "A" IMP. @5k
Get with Paul (lakes only) and he can help you on the set up on your ford.
Tim
if you turn more rpm in a lighter boat then there was something amiss in the current setup. you should spin the same rpm in a lighter boat and it should go faster and will be quicker. i would say that you have a 25' boat wit a mild 460 and thats about all you going to get out of it. good luck and have fun most important!
i'm not looking for neck breaking launches,i bought the boat second hand (cheap-real cheap),with a trashed pump,overhauled the pump,put a new intake and carb,all gaskets and bearings in engine,running a weind stealth,barry grant 975cfm carb,ford ms aluminum super cobrajet heads,
crane roller rockers w/girdle(not sure why),.60 over block,comp cam #34-311-4,.542 lift, 286 duration, with hardin logs and msd 6al, shouldn't the motor set up turn more rpm's?? with an a impeller (bronze)???
Just get a 20' cruiser and be done with it. My cruiser has 425 HP and goes 68 all day long spinning an "A" IMP. @5k
Get with Paul (lakes only) and he can help you on the set up on your ford.
Tim
Gregr , only turning 4400 with an "A" , describing your specs ,that engine must be tired.A healty 460 should turn a min 5000 with an A imp. You're also over carbed . An 850 would suffice .There are some bugs to be worked out :idea:
Gregr , only turning 4400 with an "A" , describing your specs ,that engine must be tired.A healty 460 should turn a min 5000 with an A imp. You're also over carbed . An 850 would suffice .There are some bugs to be worked out :idea:
iam with spectras i would say your a bit over carbed , my stock spectra when i had it would pull 4800 rpm on a berk a impellor and would go 53. that is with the stock 460 with d3ve heads and a 850 carb with the super cobra jet manifold. are you sure its a "a" impellor and not a "aa" impellor you said it might be a bronze so it is possible that you have a "aa" in there. ( i guess it would be possible with the aluminum as well) plus the aa would move the bigger boat better. i would look at the impellor and your carb. if you dont mind who built your pump? also one more thing what chip is in you msd 6al i would put 6000 in it.
iam with spectras i would say your a bit over carbed , my stock spectra when i had it would pull 4800 rpm on a berk a impellor and would go 53. that is with the stock 460 with d3ve heads and a 850 carb with the super cobra jet manifold. are you sure its a "a" impellor and not a "aa" impellor you said it might be a bronze so it is possible that you have a "aa" in there. ( i guess it would be possible with the aluminum as well) plus the aa would move the bigger boat better. i would look at the impellor and your carb. if you dont mind who built your pump? also one more thing what chip is in you msd 6al i would put 6000 in it.
mikes pump and speed out of houston overhauled and it does have a legend (a) bronze impeller, i have a holley 750hp double pumper,would that help? I cant throw out another 900.00 on a carb anytime soon,As for the engine,it is tight,i did use the same pistons(new rings).....bad????
Like i said earlier, Im no ford guy but with specs, it looks to be way off on the carb, cam and exhaust issues, Get with lakes only he will steer you right on the set up.
ok the impellor is a :a: so thats not your prob i would try the the 750 and see what happens . good luck and contact lakes only he is the ford guy and knows his stuff. what modual do you have in your msd? 4500, 4600, 5500.... i have had a modual that said it was 6k and it was more like 5700 so that is a simple one . and as for 900 on a new carb i would go with the mighty demon and that is about 500 for th 850 dp. sell your carb if the 750 helps. good luck
whats up fellas? I got got another speed question for you all--i have a 1977
sleekcraft 25' day cruiser,healthy 466 bbf, berkley pump with a legend "a" impeller,jg split bowl,4 degree wedge,ss loader,place diverter, (pump has about 45 min on it),my question is ...how fast should i go? i feel that the motor WILL turn up more rpm ,but does the big ass boat have something to do with it? If i were to put the same exact motor & pump in a lighter boat what would i gain?, more holeshot,more rpm,more speed? OR will my motor still only turn 4400 rpm in a lighter boat? I am in the process (slowly) of totally restoring a 1978 sleekcraft aristrocat 20',dual tunnel design, would i go any faster with that hull? HELP PLEASE!
i'm not looking for neck breaking launches,i bought the boat second hand (cheap-real cheap),with a trashed pump,overhauled the pump,put a new intake and carb,all gaskets and bearings in engine,running a weind stealth,barry grant 975cfm carb,ford ms aluminum super cobrajet heads,
crane roller rockers w/girdle(not sure why),.60 over block,comp cam #34-311-4,.542 lift, 286 duration, with hardin logs and msd 6al, shouldn't the motor set up turn more rpm's?? with an a impeller (bronze)???
Every one says that the engine should spin the same rpm no matter what boat it is in. Is that a special cut cam ??? That particular part number, #34-311-4, does not show up in the Comp Cams catalog. It sounds like the cam should be around a 2000-6000 rpm range, but without knowing all the info on the cam it is hard to speculate. But with the heads that you are running I would expect to see 5600-5800 out of that motor with a AB impeller. Now are you running race gas - 110 oct ??? Being those heads are 74cc if you have flat top pistons at 60 over you will be somewhere around 13 to 1. Also if your cam timing is not correct along with the ignition timing you will run into that plus the fuel. Give me a call, you need help.
Jim
ok the impellor is a :a: so thats not your prob i would try the the 750 and see what happens . good luck and contact lakes only he is the ford guy and knows his stuff. what modual do you have in your msd? 4500, 4600, 5500.... i have had a modual that said it was 6k and it was more like 5700 so that is a simple one . and as for 900 on a new carb i would go with the mighty demon and that is about 500 for th 850 dp. sell your carb if the 750 helps. good luck
Mighty Marine Demon 850 cfm part number 5563020GM at Jegs is $574.99.
Every one says that the engine should spin the same rpm no matter what boat it is in. Is that a special cut cam ??? That particular part number, #34-311-4, does not show up in the Comp Cams catalog. It sounds like the cam should be around a 2000-6000 rpm range, but without knowing all the info on the cam it is hard to speculate. But with the heads that you are running I would expect to see 5600-5800 out of that motor with a AB impeller. Now are you running race gas - 110 oct ??? Being those heads are 74cc if you have flat top pistons at 60 over you will be somewhere around 13 to 1. Also if your cam timing is not correct along with the ignition timing you will run into that plus the fuel. Give me a call, you need help.
Jim
the pistons are a dish type,the grind # on the cam is (ff 312ah-10)
jet boat with a/b impeller,rough idle, 108 lobe seperation,try p/n 311-4,msd has a selectable rev limit set @6400
Posting Permissions