About what hp should I have with this set up???

jrturbo

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Just got my engine built and wanted to know if any one can tell me what hp I should have I got a 1988 350 with flat top piston, bore .030 over, flat tappet cam 291 int 287 ex. .050 DUR 224 int 224 exh with upgrade springs. heads valve are 1.94/1.50 stainless steal. quadrajet 600.
 

Bondo

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Re: About what hp should I have with this set up???

Ayuh,... Probably 'bout 280hp, or so...
 

180shabah

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Re: About what hp should I have with this set up???

agree-ish

A little snappier than "stock" but not at risk of tearing anything up.

Just make sure to break it in properly and prop it correctly..
 

jrturbo

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New reman engine 350, what to know about what hp I will be getting out of this with

New reman engine 350, what to know about what hp I will be getting out of this with

I just got my motor rebuild and ask them for an upgrade cam and springs. Here is what my engine has it has 193 heads w/ ss valves, flat top pistons, cam spec This is a boat engine ===Cam specs Cam lift 300 int .307 exh., valve lift .450 int .460 exh. Lobe CTRS int 114 exh 114, SAE DUR 291 int. 287 exh , .050 DUR 224 int 224 exh. Oh and it is bored 30. It is bored 30. Thanks guys..
 

jrturbo

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Re: About what hp should I have with this set up???

what prop should I use i have stainless 17 right now.. I was hoping to be around 300hp. do you think i will be?
 

HT32BSX115

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Re: About what hp should I have with this set up???

what prop should I use i have stainless 17 right now.. I was hoping to be around 300hp. do you think i will be?

There's really no way to know unless you put it on a dyno and measure it.... If you used a 17p prop before, you'll have to run it and see if it exceeds your previous WOT RPM. If it does, you can probably go to a 19p

I wouldn't expect it to exhibit a HUGE difference. It's still just a 350
 

AZSenza

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Re: New reman engine 350, what to know about what hp I will be getting out of this wi

Re: New reman engine 350, what to know about what hp I will be getting out of this wi

Without knowing what kind of intake and fuel system you've got, I'd guess around 320hp at the crank. That exhaust duration is getting pretty close to water ingression! What kind of boat and exhaust are you running? Your compression might require premium fuel too, with flat tops on a 350 and 64cc chambers it will put you close to 10:1 CR.
 

Incorrigible

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Re: New reman engine 350, what to know about what hp I will be getting out of this wi

Re: New reman engine 350, what to know about what hp I will be getting out of this wi

Who did the work? They should be able to provide you a rough estimate of power output based on their work.
 

haulnazz15

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Re: New reman engine 350, what to know about what hp I will be getting out of this wi

Re: New reman engine 350, what to know about what hp I will be getting out of this wi

I'd say between 265-280HP or so. What is more important is where the power peaks at in the rpm-band. If your cam is too aggressive then it won't peak until higher in the RPM range, possibly outside of the max-RPM for your outdrive.
 

jrturbo

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Re: New reman engine 350, what to know about what hp I will be getting out of this wi

Re: New reman engine 350, what to know about what hp I will be getting out of this wi

I dont want to say who did it, I just want to know what others are going to say to see if he did what he was supose to. it is a stock intake, quadrajet 600 carb, with electronic fuel pump , exhaust will be an glm alumium exhaust and risers. Boat is a 19 foot 1987 celebrity open bow with and alpha 1.
 

jrturbo

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Re: New reman engine 350, what to know about what hp I will be getting out of this wi

Re: New reman engine 350, what to know about what hp I will be getting out of this wi

I thought these head were 76cc..
 

jrturbo

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Re: New reman engine 350, what to know about what hp I will be getting out of this wi

Re: New reman engine 350, what to know about what hp I will be getting out of this wi

bump
 

John_S

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Re: New reman engine 350, what to know about what hp I will be getting out of this wi

Re: New reman engine 350, what to know about what hp I will be getting out of this wi

I thought these head were 76cc..

You're in transition year range. If it had flat top pistons, you have 76cc heads. If recessed pistons, then 64cc heads.
 

Bondo

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Re: New reman engine 350, what to know about what hp I will be getting out of this wi

Re: New reman engine 350, what to know about what hp I will be getting out of this wi

You're in transition year range. If it had flat top pistons, you have 76cc heads. If recessed pistons, then 64cc heads.

Ayuh,... Shouldn't the head casting numbers clear up that question,..??
 

John_S

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Re: New reman engine 350, what to know about what hp I will be getting out of this wi

Re: New reman engine 350, what to know about what hp I will be getting out of this wi

Ayuh,... Shouldn't the head casting numbers clear up that question,..??

Should, if he wants to take the time and get them and look them up. ;)
 

jrturbo

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Re: New reman engine 350, what to know about what hp I will be getting out of this wi

Re: New reman engine 350, what to know about what hp I will be getting out of this wi

I would just like to thank everyone for there input. The original pistons were dish, I asked for flat top. I wanted to be around 300 to 320 hp, and am wondering if with all the spec I have gave to you guy is it there. Like he told me. I want to make sure the cam will get me up there. but it is sounding like he did not do what I ask if people are saying 265 to 280hp..
 

jrturbo

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Re: New reman engine 350, what to know about what hp I will be getting out of this wi

Re: New reman engine 350, what to know about what hp I will be getting out of this wi

Now I feel ripped off..
 

90stingray

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Re: New reman engine 350, what to know about what hp I will be getting out of this wi

Re: New reman engine 350, what to know about what hp I will be getting out of this wi

Its hard to make tons of power in a boat if you don't want to spin it over the original max rpm's... Unless you go with more compression. Which you have done with the flat tops. But like people are saying... you start camming it up, then your rpm range moves up and you have to spin the motor faster. Marine engines are such a different animal than an auto. If the builder is quoting you 320... see if he wants to strap it to a dyno and see what she does :)
 

RZR2007

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Re: New reman engine 350, what to know about what hp I will be getting out of this wi

Re: New reman engine 350, what to know about what hp I will be getting out of this wi

A stock 600cfm carb will not feed a 300hp + motor, too big of a cam will kill a basically stock motor throughout the lower to mid RPM range, low compression motors don't make alot of HP unless super charged or blown, high compression, big cammed engines have to be able to breath (port work in the heads, bigger valves, etc) Point being, there is alot more to making HP then installing a big cam, this is a common mistake and more often than not, a smaller cam in the same set up motor will be faster....
I would use a mechanical fuel pump with the quadrajet, they don't respond well to alot of fuel pressure...
 

jrturbo

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Re: New reman engine 350, what to know about what hp I will be getting out of this wi

Re: New reman engine 350, what to know about what hp I will be getting out of this wi

what is water ingression and why would I have it.
 
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