1974-351 windsor intake

TRBenj wrote:    Didnt you try a 12x13 OJ, Gary? That prop should have pushed the boat well. I like the Acme 1210 better on my Skier, but both are good wheels. The one detractor to installing the P heads on the earlier 289/302 is the drop in compression you'll see.

I tried one before the head change Tim. Reid let me try an OJ 12x13 and a Federal 12x14.The Federal was better up to the high 30's and 4k then neck and neck with the OJ.The OJ did give me an extra 100 rpm's at wot. I'm still using the Federal. The head chamber volume is really close to my originals,my old heads,D20E-BA were 58.3 and the P's are 58.8
In my haste to put the heads on,I forgot to cc my block,but my flat top pistons are .030 over.So I don't know what my compression ratio really is.

Okay I screwed the pooch on this one. Next time I won't buy anything until I make a thread and let it get kicked around for atleast two weeks. But for real with the specs. I left earlier on the cam and going with the RPM intake. What do you guys think I will run? If someone would like to cutt me a check for the GT40P heads fell free. LOL

Thanks for letting me know I screwed up on the Intake and cam purchase.
When were young we can't win them all. Especially since my boat has 11 years on me.

Thanks Clark Slaten

Clark, that cam doesnt look too bad, actually- if you were upgrading the heads, that is. Usually the cam is the final piece of the puzzle- a good cam builder will take all the other components and specs (heads, intake, compression ratio, etc) into consideration, talk to you about the application and your goals, and them come up with a recommendation that will work best. That being said, that Comp Cam isnt too far off what I have in my '90 (351w with GT40p/Stealth/etc). I would highly recommend you make a decision on the heads first, then pick an intake, and then call Cam Research instead. They only do Fords and they do ski boats- many of us here have been very pleased with their products.

Gary, Ive noticed about a 200rpm difference between the OJ 12x13 and Federal 12x14 (the OJ running higher). I thought the holeshot with the OJ was better though. Top end was close. The Acme 1210 Im running now turns 100 more rpm than the OJ. The engine seems to like more RPM... of course my Skier is only turning 4200, 4400, and 4500 with the 3 props, respectively... its an underperformer. Do you still have your cam specs?

Hey thanks for all the great advise.

That's why it took me so long to get this posted Tim. The numbers don't add up and I wanted to check everything. Although the lift on that comp cam is close to what you're running the valve timing events are not so that must be the difference. I guess Cam research specializing in Fords plus the fact that he's run ski boats for years must be worth something.

Also don't overlook the stock exhaust manifolds and mufflers.

Cslaten33 wrote: I don't know if this makes a differnce but I'm running stock mannifolds with straight pipes.

Biggest problem with this program is that it really doesn't allow for marine exhaust so there are some assumptions I have to make get reasonable results. The stock manifolds and mufflers option is about as close as I can come to what we have on our boats for exhaust. The next option is headers with mufflers and the number jump nice and high but it's not practical for us unfortunately.

Tim getting back to the cam, there's a module of desktop dyno called Pro Iterator and what it does is take the engine you enter in the system and run test simulations on it based on user input. For instance, I ran a sim of Clarks engine as it sits now with the stock heads, his comp cam and a basic dual plane intake. The program takes his cam lift and then runs simualtions using differentcam event timing and tries to define better specs for torque, HP, torque or HP under the curve.

When I ran Clarks motor the program came up with 11,300 different interations and it found him 29.5 hp using teh same lift on his comp cam but spec'ing new timing events. Only problem I have with it is it's an advanced feature that I have to buy and add on so it lets me use it and shows what I could achieve but won't give me the specs to get there without buying the upgrade.

I also ran yours and it only found 3.2 HP so again cam research is pretty darn close on these things. I'll buy the upgrade soon because it could be interesting and you know if I wasn't working on teh Hurricane the "other" tool box would be out.

With my heads, I find I am really under cammed. Came up with about 16 hp (396 at 5600rpm)and stretched the torque out further to the right. I know this is all speculating but it is fun.

Here's one I found with a little more speed,but still looks to me, bow down.

Gary, those numbers are underperforming for sure. If I didnt know that you had removed all your foam, Id say you were carrying some extra weight! Something is definitely going on there...

Marshall's boat definitely rides bow high. I dont believe its ever been ground- if it has, it was minimal. I believe Reid's baby blue ran more bow-low initially, and it took a lot of grinding to even them up.

TRBenj wrote: I believe Reid's baby blue ran more bow-low initially, and it took a lot of grinding to even them up.

Tim - Just curious - what do they grind on the hull? Do they take the hook out?

How do you guys know about all of this???
The company that I bought my cam from, do you guys think they will take it back for exchange since it is still in the plastic wrap and box??

Clark, If I am assuming correctly,you have purchased a LH 351 long block and your original engine was a RH reverse rotation engine. If this is the case you would need to change the starter to a LH standard rotation starter. You would have to change the prop to a LH prop. You would need to reindex your transmission pump 180 degrees to flow properly and also turn your RWP around to flow the opposite way.The distributor would also have to be changed to a LH. Off the top of my head I can't think of anything else but there might be more to do. This can all be done easily but are you sure you want to do it.

and pistons backards

I'm sure someone else will chime in about the fuel injection, but what is your purpose for switching from a carb?

Cslaten33 wrote: better throtle responce in colder weather.

Clark,
You've never mentioned you were building a ice breaker!! I thought you were going to restore the boat??