this really sucks?
 

on 35 1998 lightning iam very unhappy with the performance after my engine upgrade this is why.

before the upgrade with 1998 tired motors one motor had 90 compression on 2 cylinders the boat ran 72.1 gps full fuel,2 people, spinning 26 hydromotives @5000 rpm wot.

the upgrade was asm, new upgraded crane cam, dart heads, msd ignition, roller rockers, cmi exhaust and a computer reflashing. cost of parts was approx 18,000.00.


heres what the performance is now(it sucks)
between 1/2 and 3/4 fuel,2 people, 26 hydromotives compression is back to 150+ on all cylinders. boat ran 74.4 gps @5000 rpm
water and wind were the same before and after.

the only thing i did not do was change the intake to get more air into the motor. do you guys think this is hindering the new heads and cam from working properly ie creating more hp?

Re: this really sucks?
 

Who did the work? What did they say about it? That seems like alot of $ for no gain.

Re: this really sucks?
 

Briana

I don't se your suprise, you are spinning the same props at the same RPM ???????? and you actually gained 2mph I find that pretty impressive. Are your rev limiters set at 5000rpm?? I would first try some bigger props, more HP doesn't help if you don't push more water either by more RPMs or higher pitch prop.

Good luck either way

WILL :drink:

Re: this really sucks?
 

What engines are we talking about? 502 mags or HP 500's?

Re: this really sucks?
 

If he's running 26 hydro's from the factory then my guess is the boat came with hp 500's. That was the standard prop/engine combo from the factory for the 35 ex's. He should be able to push those to around 5300 and 80ish mph.

Re: this really sucks?
 

they are 502 mags and the rev limiters are set at 5700 as per az speed.

Re: this really sucks?
 

Have the motors been given a chance to "run in"? May need to run them a bit to see how they do. Also, how old was the gas and if it was new, is it the "winter formulation"?

Re: this really sucks?
 

So what's the story on this boat. What did the boat run before you lost compression - rpm and speed?

I'm surprised it was propped with 26 hydro's if the boat only had 502 mags. My 35 with hp 500's came with the same props.

How much HP are these motors pushing - or suppose to be pushing? What were you expecting out of them?

Re: this really sucks?
 

this was an upgrade package from arizona speed marine my mechanic did the work.

doesn't higher pitch ie 28 or 30 mean less rpm, i was told basic rule is 1-2 degree is approx 400 rpm loss or gain depending on the way you go.

ex 26deg 4bl @5000

28deg 4bl@4600

24deg 4bl@5400

Re: this really sucks?
 

I take hp # gains with a grain of salt

az speed claims my set up should have brought these motors to 515 to 520 at the crank.

i was hoping to get similar performance to 35 with 500hp's which is 80ish.

what type of prop would you guys recommend?

Re: this really sucks?
 

fuel is fresh i live in sw florida 12 month boating season

Re: this really sucks?
 

Did you dyno the engines? Have you done any testing? How do you know that the engines are making any more power? There are a lot of issues that may be going on if you do not know what the engines are doing. Everything has to work together! If i were to guess, the power is not there.

Re: this really sucks?
 

I don't think your problem is with the prop pitch. You just aren't generating enough HP to turn the props you have. I guess there is an outside shot that your rev limiters are set to 5000. One way to check that would be to throw a different size set of props and see if they maxx out at 5000 as well.

Re: this really sucks?
 

no dyno was performed, the set up should produce more power brings me back to the air issue, the standard intakes are really small on 502's, if i hone out intake will this complete the upgrade and give me the hp iam looking for.

Re: this really sucks?
 

rev limiters are not set a 5000 as the ddt shows throttle @100% @4950 rpm

ran a set of 30 b1 and only turned 4600rpm

this is a motor not producing the horsepower it should be.

Re: this really sucks?
 

So what did ASM have to say about their upgrade? Do they have any suggestions?

Just curious, did you compare the cost of buying some low hour takeout 500efi's or 525's over upgrading your 502 mags?

Re: this really sucks?
 

I am not an engine expert by any means but i think it stems from no hp gain and / or airflow to get the hp. Your 2mph gain could have been from the new exhaust alone. You have all new parts and good reliability, try getting more air into the engine to create that hp, remember the engines are still tight too so maybe get some run time on them first.

Good luck, i am sure it will all work out.

Jay

Re: this really sucks?
 

Did you change the stock arrestor?

I know you are in FL but even here in GA the fuel is oxygenated this time of year and that can make a difference. With all of the games with fuel these days, you never know what you have. What grade are you using?

Most engine builders will tell you not to run the motors wide open until they are broken in. How much time do you have on these motors since the rebuild/upgrade?

Re: this really sucks?
 

My .02 cents. I would try a set of smaller props to get your RPM's up. With Hydromotives each inch of prop change is equal to about 200 RPM. I would think that with the new heads and cam in your engines it moved your horsepower and torque up in range, and you need more RPM's to realize the gains.
I would think you would want to turn your engines around 5400 to 5600 rpm.

Re: this really sucks?
 

changed to k&n filters, and yes the motors had 3 hours ON them before wot was tested for a sustained period of time(MAX SPEED, UPTIMUM DRIVE HEIGHT)

Re: this really sucks?
 

with stock 502efi's 415HP the boat new ran 75 to 77mph

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The Report From The Factory Says 76 Mph Found This In The Owners Manual With My Hull # And Wind Condition, Time Of Year, Air Temp And Humidity.

Re: this really sucks?
 

My report said 75 mph. Our drive heights must be about the same.

Re: this really sucks?
 

I second the idea of putting less prop on and turning higher rpms!!!! Until you spin over 5000rpm I think the rev limiters are stuck, just my 2 cents,

WILL :drink:

Re: this really sucks?
 

rebel heart, what is your drive height, I dont have that info on mine.

Re: this really sucks?
 

have you run a straight edge on the bottom? check with JC performance he can tell you whats wrong if you give him the build specs.

Re: this really sucks?
 

PS also allways dyno you spent a lot of bread another grand at most you could have played with them on the dyno. we found another 50 hp on a 900hp playing with jets, plugs and timing

Re: this really sucks?
 

hmmmm, I'll throw out a thought from experience. Did your mechanic actually do the work he said??? Lots of unsavory mechanics out there. Trust me, I think I found them all!!!

Re: this really sucks?
 

I would verify timing first and then take a careful look at the fuel system.

Re: this really sucks?
 

THROW IT IN THE WOODS......then you wont have so much stress :D

Re: this really sucks?
 

Without knowing exactly what's in your engines, it's really hard to pinpoint the hp you SHOULD be making. But, nevertheless, you should be running faster even with a stock setup. You're just not making any more power than you were before.

Time to start doublechecking EVERYTHING. Your manifold is'nt helping your situation, but I'm sure that's not your main problem.
What does your engine builder say? He should be making some changes to improve your speeds. He's the one that knows what he put in the engines and how everything was installed.
Did you take any plug readings?
Where's your total advance at?
Take the chip out of your revlimiters and try it that way.
I doubt both chips are bad, but that'll eliminate that idea.
Where were the cams installed at? Possibly maybe too much advance, or retard.
What roller lifters are you using? Some styles are designed to be set at 0 plus a half a turn, some are designed to be set at 0 to -.004 If you don't have the lifters set properly, you could be not letting the valves close all the way, and therefore you'll be losing a considerable amout of power at the top end.

I'm sure it's just something real simple that might've been overlooked during assembly, but it's something that's been done to both engines unknowingly.

Re: this really sucks?
 

Briana - talked to Chris at Fountain this week. They didn't have my hull number with the x dimension, however, he said the boat made right after mine had 16 3/4. So he thinks mine shoul be the same. No wonder these new executioneers are running near 80 with the x-dim. at 19. This is why I think that i would benefit from a 2" shortie.

Re: this really sucks?
 

If you are spinning the same 26" props at the same 5000rpm at both before and after the change, you should have the exact same speed to the 1/1000th. Doesn't matter if you have 5 HP or 2000HP. The design of all the parts you put in, heads, exhaust, whatever...was not the cause of your 2mpg gain. You gained the speed from either a loss of weight from the new parts, or the temp/water conditions were different between the 2 runs.

I suggest trying a set of smaller props to check that you can spin the motors faster. If you can, then you don't have the HP to spin 30" props, try 28".

Re: this really sucks?
 

briana - were you over @ Rumrunners on Thursday? I was down on vacation in Ft Myers Beach this past week.

Re: this really sucks?
 

no, was at snug harbour, on fort myers beach last sunday, was over at rumrunners today saturday.

Re: this really sucks?
 

us1 fountain, i always thaught more horsepower, more prop,
now that the motors are set up to run more rpm 5700 rev limiter. do you thing my missing speed increase is somewhere between 5000rpm and 5500 rpms, maybe run 24 bravos, or 22 hydros.

Re: this really sucks?
 

Yes, more HP means you should be able to turn a larger pitched prop. A larger prop will move further forward for each revolution than a smaller prop. BUT, you have to have the HP to turn it. Since you were able to turn the 26" before @5000rpm, you should be able to go up, such as a 28" now that you have more HP. But you have acheived ZERO rpm gains. Are you sure your rev limiters have been increased? The reason we all suggest trying smaller props, 22,24" is to make sure your motors can and will indeed spin more than the 5000rpm you are currently getting. This is the quickest/easiest check if you have access to a couple smaller props. If you can then spin say up to 5400, then we know A) that your rev limiters are not holding you back, B) you need to look at your motor work. I'm just surprised that both motors are on the same playing feild.

Re: this really sucks?
 

well, enough of this crap, just talked to the guys at innovation marine in sarasota, and they are getting me on the dyno schedule within the month and well then see what is going on.

Re: this really sucks?
 

what is the lift and duration on the cam?

Re: this really sucks?
 

i hate tio admit this!!!
dont spend money on old technology!!!
i had early 90's 35 i spent a mint on it,, STUPID!!
Just buy a bout that runs what you want it will be cheaper..
to get my old boat to go what my new boat does i would have had to insert it into the space shuttle.. : )
no but really it makes no sense throwing good money after bad i lost my azz.. just upgrade your program and you will have reale and more fun,, my 02