Cam Question
 

Spoke to a couple dyno guys and realized I wish I never would have put my blowers back on for my style of boating. So, If I wanted to pull my blowers off (177's) and just go NA could I get by with this cam that I already have in it?

Specs: .235int and 241exh - .646int lift and .629exh

Gen 6 -502's with GM heads, cmi's.

Any thoughts? Not trying to make any power, just want simple and low hassle for a couple years.....

Personally I'd say they look pretty good NA or SC. You'll. Be fine. Assume they're 114 lsa
Either way you'll have good cams. No worries. Use them. You won't be sorry.

You will probably loose 75-100 hp by removing them and going NA. What is the comp ratio???
You will probably need to drop down in prop pitch as well.

177's should be simple and hassle free. there will be some expense to buy different intakes and carbs if you ditch them. I would be more worried about compression ratio than I would the camshaft

what compr ratio do you have?

Merc motors were all generallylow compression anyhow. Mostly in the 8.75:1 or so range. I don't think it would be that big of a deal.

Ya designed to run 87 octane. The "SC" series with blowers were what? 7.5:1? Way low...

Comp Ratio is 9.1.

I don't mind losing the power. My problem is with my constant idling, and delicate way I cruise around I am always running rich. The discussion was that with those small blowers and the heat they make you have to really run rich - Hard to find a balance between leaving enough jet in it to protect it at WOT, but allowing me to cruise around at 3,200 like I do 99% of the time I'm on plane.

Just some tuning... you already verified power valve size and PVCR size correct? A common mistake made, is that guys have great AFR cruising/idling then worry about lean up top... To correct this issue they enrichen mixture screws (Which has very little affect at WOT or cruise), and they put larger jets in (Which affects everywhere from off plane driving, cruise, and WOT). They overlook to tuning where they specifically need the fuel at WOT (PVCR).

You need to dial in a clean idle with the mixture screws. Then leave them. Then dial in clean cruise with the main jets Verify vacuum so you make sure the power valves are shut... Then leave them. Then dial in PVCR and power valve for WOT. Now if you find it terribly lean at WOT you don't want a crazy amount of PVCR and small main. Reason being is when the power valves open you have a huge change in fueling. But its not uncommon to require high flow power valves to support enlarged pvcr's. Now at the end of the day, you have a clean running boat idle and cruise. Then proper enrichment for WOT..

with the right carb and proper tuning a good air fuel ratio from idle to wot can be had with the blower.

What carbs do you have? It is not to hard to clean up the idle circuit . And cheaper too.

Single Holley 850....

You getting some advice regardless. Back to your original question and moving forward I wouldn't hesitate to strap a hp 950 on top of a Vic jr or dart and go enjoy your boat. I know what your talking about and been down that road. I'm assuming your 1050 is 3 circuit. Those carbs were originally designed for pretty much one thing and it was drag racing. Allowing to translock and not lean out. If you call pro systems and had them build you a carb for your app I'd almost bet on them going 4150. Not a 100% on 502 but they do on 454/177.

1050 dom obviously works also but just saying... Call and ask them. Two minute call. Also if you know who ground the cam and have the cam card just call them to make sure your valve timing etc is acceptable running at 9:1 static. I'm pretty sure you'll be safe but call. It's all about you and enjoying your boat with the way you run it. Many on here have completely different boating characteristics myself included. I have very little idle time and run relatively hard.

Again to be certain call who ground the cam or spec'd it. It doesn't sound like a shelf cam.

At the risk of derailing the thread, I'll give you one guess who spec'd the cam. I have the Cam card down in the garage.

I am laughing harped at your "cross threading is better than locatite".

If I wanted to shelve the blowers for a couple years which intake would you guys recommend? Just trying to do some research....

IMO, carb is too small for a SC'd 502, but the 177's are too small also.
Probably jetted the carb rich to compensate being on the small side.

If you go NA, the carb should work fine for that. I would prob go with a Dart intake manifold.

Have a look at the RPM Airgap manifold. In my googling they've been consistently better for the power range that you live in. For folks that spend a lot of time wide open the single planes are great.