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-   -   Looking for 400hp small block for cat (https://www.offshoreonly.com/forums/general-boating-discussion/267089-looking-400hp-small-block-cat.html)

Originalronza 12-13-2011 07:46 PM


Originally Posted by HaxbySpeed (Post 3570578)
If you bump your budget up to about 12k per side I can hook you up with LS3's 450hp, all aluminum, closed cooled, turn key ready to go..

Are they fuel injected motors, do they have headers? If they do sounds very good, do you know the weight

Originalronza 12-13-2011 07:49 PM


Originally Posted by Philm (Post 3570060)
AMT made a twin small block powered 30' cat that ran right around 105mph with twin 390hp SBC. Set up on drivelines. From what i understand they only made one, but also based on the reviews of it, it ran pretty well for that power package. They were from PCM engines, originally the ZR6 package, now they are called the ZR409.

I know that Arnaldo at Predator will build you the same boat, since they have the AMT molds now. That is one of my ideas for a new boat.

That sounds like a hell of a package, that is smoking fast for that power. What drives were used? Was there an article on this boat.

HaxbySpeed 12-13-2011 07:51 PM

They are EFI and drive by wire, they can run analog or digital dash. They come with aluminum exh. manifolds. CMI's are available for a significant upcharge and not worth it in my opinion.

Philm 12-13-2011 08:00 PM


Originally Posted by Originalronza (Post 3570585)
That sounds like a hell of a package, that is smoking fast for that power. What drives were used? Was there an article on this boat.

There was an article in Powerboat, back in '08 i believe. You can buy the article from Powerboat magazine, $3.99

The boat had IMCO SC's with SC lowers. Sitting on IMCo extension boxes.

I already talked to Predator about building me one, Arnaldo said no problem, small blocks or big blocks, up to me.

http://i690.photobucket.com/albums/v...006sport02.jpg
http://i690.photobucket.com/albums/v...006sport09.jpg
http://i690.photobucket.com/albums/v...006sport05.jpg

Originalronza 12-13-2011 08:34 PM


Originally Posted by Philm (Post 3570591)
There was an article in Powerboat, back in '08 i believe. You can buy the article from Powerboat magazine, $3.99

The boat had IMCO SC's with SC lowers. Sitting on IMCo extension boxes.

I already talked to Predator about building me one, Arnaldo said no problem, small blocks or big blocks, up to me.

http://i690.photobucket.com/albums/v...006sport02.jpg
http://i690.photobucket.com/albums/v...006sport09.jpg
http://i690.photobucket.com/albums/v...006sport05.jpg

Cool looking boat, would love to put their 550hp motors with some arnesons, bet you would be in the 130-140mph range on modest reliable power. Or maybe ilmors new 550s what a package.what kind of price would you be looking at on this boat and motor package?

mike tkach 12-13-2011 09:35 PM


Originally Posted by Mad Mac (Post 3570097)
:lolhit: ignorant SOB arent you, seams to me I know quite a few 110+mph 30' and 28' cats with twin 300HP egg beaters that will run. I think you need to start reading a little about the subject HP to weight ratio. The Ls engines that the others have mentioned are putting up bigblock power without the weight.

NO I AM NOT AN IGNORANT SOB,the origional poster said,400 HP IN A 30 FT CAT WIL DO 120 MPH.he did not say outboards on a 30 ft cat,had he said,pair of 400 hp outboards on a 30 ft cat,i would have not questioned it.thanks for telling me about power to weight,or as you put it [HP TO WEIGHT RATIO].maybe you should look at the torque figures on those packages.i stand by what i said,if you think that makes me a ignorant sob,thats your problem.the fact is it makes me a informed person,who knows something about 30 ft cats with the engine IN IT.so who,s the ignorant one now?:lolhit::lolhit::lolhit:my post stated that a 30 ft cat with a pair of 400 hp engines IN IT,will not run 120,i did not say 400 hp cant be made with a small block engine,you can buy 400+ hp small block from gm,and thats with less than 10 to 1 compression ratio.

kilrbusa 12-14-2011 02:38 AM

Hax--what exhuast you using ?

Who makes best exhuast for LS3/LSx besides cmi for reasonable $$

the 406sbc is a killer motor for the $$ and HP...500hp all day long for cheap.

Philm 12-14-2011 07:17 AM


Originally Posted by Originalronza (Post 3570617)
Cool looking boat, would love to put their 550hp motors with some arnesons, bet you would be in the 130-140mph range on modest reliable power. Or maybe ilmors new 550s what a package.what kind of price would you be looking at on this boat and motor package?

We didnt get to hard numbers, but the hull and interior is just shy of $70k, add $20k for rigging and $60-75k for engines and drives (of course it can be ALOT more depending on the level of performance.)

I would figure that the lowest you could get out the door would be in the $160k range for a brand new custom 30' cat.:coolcowboy:

Someday.....:evilb:

IlmorGirl 12-14-2011 03:05 PM

Don't forget, Ilmor has two small block MV8 engines from our new line with over 400hp - the all aluminum 6.2L at 430hp and the performance-based 7.4L at 522hp. Check them out at: http://www.ilmor.com/en/marine/recreational/

teaguecustommarine 12-14-2011 06:12 PM

you are going to limit out those small blocks pretty quick and start to lose reliability.... Just the CMI on the LS engines start at 4k!

Stick with big blocks! Depending on the boat, the weight might actually help keep it settled at speed.. If you had Merc 454/502's you can rebuild them to 500HP+ for cheap and kill the small blocks and be super reliable! Then down the road.... convert you Big blocks you invested a little money into and add some blowers, now you are talking the speeds you are wanting to reach!

Twin 400hp in a 30 cat is likely to only go 85+? ....depending on the boat and the set up of course. Inboards and outboards are playing different games so you really can not compare...

Another thing to consider is, it depends on the boat how fast it wants to go.... Not all boats are created equal and there is no exact equation to HP vs Speed!

Eric

TEAGUE CUSTOM MARINE
661.295.7000
www.teaguecustommarine.com



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