Want more sound(Holman Moody 302)

I can't answer your questions Ryan...but welcome....you are my kinda guy.

john

HM302 add a set of GT-40 heads and a set of Hi-Tek Stainles Steel Exhaust manifolds.These two mods will possibly get you a citation from the Water Cops.
The heads will raise your compression ratio the manifolds will increase flow.Your little 302 will pick up a few HP and loose some weight to boot. Both are a win win in a boat..........Boat dr

John, I think that you and I are right on with the 80s. No mufflers needed. Keeps the mosquitoes away.

I asked Reid to take my boat out at GL to help me with a vibration. His 1st comment was that there were no mufflers.. then he nailed the vibration to the Prop. So I guess the noise did not distract him.

HM302/Ryan; You're the first guy I've ever heard say that his 302 HM wasn't loud enough, as they typically seem to be the loudest. Now while I hardly EVER disagree with the BoatDr, I'm not sure of two things: I'm big on the GT-40 heads, but your vintage 302 came with 351 small chamber heads which result in about the same comp ratio as the regular GT-40's. Boatdr is thinking about the more commom later model 302/351 heads which had small valves and large (low compression)chambers. As for the manifolds, JoeinNY and a few others feel that the aluminum HM's might be louder than the stainless Hi-Teks. So unless someone had installed mufflers in your boat over the years, there's little you can do to make it louder without internal mods to raise your compression and changing a cam, but that's quite a bit of work. I can certainly testify that my HM302 is now VERY loud, so since you're not too far from me we should plan to meet up sometime and you can hear it run and see if that's what you're really after. Give me a call sometime if you like. 704-451-5080.

Ryan,
At 21 you shouldn't be needing hearing aids yet so hopefully that's not it. I agree with Reid on this one. I too have never heard of anyone wanting to increase the H/M's sound level. I can here one start up from the other side of the lake and know it's a H/M from the distinctive bark they make. The only louder boats are V drives or I/O's with rear mounted engines and short through the transom exhausts. (H/M rear engines especially!!)

Have you had this boat for awhile or just get it? Does it have the original H/M manifolds or has someone put on generic cast irons? Like Reid mentioned, maybe a PO put mufflers on it! Get a flashlight and look up the exhaust pipes for signs of mufflers.

I agree with Joe and Reid. The '73 with the H-M manifolds is the loudest CC Ive ever heard. Definitely louder than my '90, which I think is comparable to the stock H-M Mustangs Ive heard.

We shouldnt forget that Ryan doesnt have a CC, though- so the exhaust set up is a bit of a question mark. Like Joe said, whether or not the boat still has the original manifolds is still a question mark. Who knows if there are any mufflers. I also cannot tell if the exhaust outlets are 3" like CC would have used... If not, then enlarging those would probably be the easiest way to gain sound.

JoeinNY wrote: I almost suspect shananigans here

Interesting!! I didn't connect the Dixie boat with H/M302 ether. I'd like to see some pictures too. Joe, the only H/M I/O's I've ever seen are in the Donzi's.

Who on site has extra "powered by H/M" decals??

Well sorry for the slow response but here are some more pictures.

Ive had the boat and been running it the past two summers over here on W. Kerr Scott. Next year I really want to go up to Lake Norman as much as I can. She sounds real good and is loud but I guess I am just looking for a little more, haha. Thanks for all the good info and responses so far fellas...
oh and as for those stickers I just went to the holman moody website and then called them and ordered them

8122pbrainard wrote: Ryan, At 21 you shouldn't be needing hearing aids yet so hopefully that's not it. The only louder boats are V drives or I/O's with rear mounted engines and short through the transom exhausts. (H/M rear engines especially!!)

Ryan,
Well, now I may have spoke too soon regarding the hearing aids!! Thanks for the pictures. A rear H/M with above the waterline through the transom exhaust - you can't get much louder! How about over the top straight pipes???

Haha maybe I do need hearin aids, everything I drive is straight piped, I love lots of sound

thanks critter

JoeinNY wrote: Whats the diameter on them there thruhulls, I almost want to say they are not 3 inches...

Good eye Joe!! A 3" or 3-1/2" O.D. on those thru hulls would certainly make it talk out loud. Ryan, you'd need a spacer of some sort around the end of the manifold (thin strip of 3" hose), but then you could go with the 3-1/2" thru-hulls for extra noise. I bought a set of these (3") and they are NICE!! http://www.buckalgonquin.com/pages/ProductPages/exhaust/tran_exh_stra_page.html
I know converting a Correct Craft from the smaller 2-1/2" thru-hulls found on many pre-70's boats to a 3" system definitely adds to the sound. FYI, most CC's with small block Interceptors, Grays, and pre '67-'68 Chryslers (poly 318's) used the smaller exhaust pipes. The HM's and later small block Chryslers all had 3" exh manifolds which dictated the hose and thru-hull size and that became the norm. Most big blocks were 3" I believe.   

Oh, and Ryan, I love those valve covers. But you've got to clean them up!

Yall know your stuff, I just measured my exhaust outlets and they are only 2 3/8". Those thru-hulls are nice reid. I think I want me some 3.5" ones. What would I need spacer wise like you were talking about? I kinda would like to get new rubber hoses on both ends that are more smoother instead of the ones with ridges.

Yea I plan on cleaning them up and doing some other odds and ends to her over the winter, I guess I have been to caught up with having so much fun driving her around on the lake all the time.

Crusader engines from the very early 70's like TRBenj (Tim's)with log manifolds used a 2-1/2" outlet on the exh's but used a short "sleeve?" of 2-1/2" hose around the exh outlet and then put the 3" full-length hose over that. That was the simple spacer type deal I was refering to above. It would be best to see if you can't find some pre-bent rubber hoses in the 3-1/2" dia as the exh hose will be hard to bend that tight. You may have to find some tight radias pipe in stainless, fiberglass or some other material and just use some very short pieces of rubber hose to make the connections, as you don't appear to have much horizontal distance to work with.

Tim, sorry we missed your initial revelation.    

If I use some 3.5" pre bent house then I can probably use smaller pieces of hose to put around my manifold and then just put my 3.5" piece over those and then tighten her down? I think thats what you were saying right
Do you remember how much those thru hulls were?..polished stainless

In terms of the smaller pieces, that's exactly what I was talking about.

As for Tim's set-up I should have been more specific as he has a plethora of CC's here.
http://correctcraftfan.com/forum/forum_posts.asp?TID=6888