Offshoreonly.com - HP upgrades for 280TRS x2

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Quote:

Originally Posted by EDT (Post 4676300)

Thanks guys !!!!! Keep the info comming !!!!!!

Small blocks with TRS in a 30' boat. Change to bilg blocks or boost. You'll have a lot of money into getting SBC's enough hp gain to make a difference. Newer lighter step boat I'd say go ahead with bulding sbc's. Blowers if internals are forged.

Quote:

Originally Posted by Rookie (Post 4676469)

If you don't know what you are talking about please don't reply. You clearly don't know what a 280trs is let alone a LT1.

Rookie is right in that you are going to spend a lot of money to get those motors into the 350+ HP range.

I say do it, but know you are going to be into it for some $$$$

good exhaust for aggresive cam = 2500
good aluminum heads = 1200-1400
rockers arms = 200-300
roller cam upgrade = 1200
intake manifold = 200
carb = 500
timing chain
head bolts
head gaskets
exhaust gaskets
valve covers
plugs
wires

This isn't all inclusive and these prices are just off the top of my head, but it's in the ballpark.

Hot small blocks, are cool.

I'd do it, but I have a rich wife.

Russ

im sure I can add 70 hp per motor for a lot less then that.

Quote:

Originally Posted by EDT (Post 4675868)

280trs mercruises are 350 cid SBC based on a 1972 LT1

'72 LT1's where listed as having 9:1 compression,hydraulic cams, and gross 300hp, net 260hp. Not as powerful as the 'famous' 1970 solid cam 11:1 compression LT-1's but they still ran pretty good.

Quote:

Originally Posted by hotrodford (Post 4676391)

search amarillo customs and performance hit the #1 result scroll down boat video / sorry ol school have to post youtube , do not know how to post here / this cam is voodoo 270 - 280 hi lift , 1.6 roller rocker / we also have a 383 w 280-290 cam 1.6 rocker / anyway point on heads is these are port , port, port , 220 intake heads , intakes are hogged , bowls cleaned , exhaust hogged , so intake and exhaust need work to fit , as in port work / motor idles like a swiss watch , very slight lope , 600 rpm pulls to 6000 / exhaust is gil dry pipe 3 in pipe 3.5 od / point of story i do not for a minute believe port size to be end all , be all of a engine build / ls , mopar , bbc all get decent ports , when its a sbc the story is they are junk , need an ls , but you notice ls has a decent head , besides on aftermarket bbc , sbc aftermarket and magic # cough , cough chev heads ,valves , bowls , and exhaust ports are the restrictions , not the intake ports // chev has nice stuff but , some of the oem original chev heads is amazing you can even sell them

Quote:

Originally Posted by hotrodford (Post 4676281)

dart , afr , world heads ,/ way beyond over vortec or edelbrock , have dart steel iron , 350 sbc 220 intake , 64 chamber , ported to hell , off late model race car / voodoo cam / rpm air gap cleaned a lil / 750 dp carb no choke / 6000 rpm / all the net experts claim it will never run , will bog , etc / carb custom built still needed lots fuel added / built motor off junkyard motor / video at Amarillo Customs and Performance /

how much speed was added over the stock 260hp engine ? from what to what ?

Your going to do all that typing without breathing and make us find your video ? :lolhit:

Quote:

Originally Posted by SB (Post 4676706)

'72 LT1's where listed as having 9:1 compression,hydraulic cams, and gross 300hp, net 260hp. Not as powerful as the 'famous' 1970 solid cam 11:1 compression LT-1's but they still ran pretty good.

https://www.nastyz28.com/camaro/z28lt1.html im going with 64cc heads/190cc int. runners to get me to 10.25 : 1 and just bought COMP Cams Xtreme Marine Cam and Lifter Kits CL12-244-4 ( Advertised Duration 278/292, Lift .498/.500) and a air gap dual plane, and getting rid of the circulating pumps. the Boat ran 60 mph stock ( 76cc heads, and the same cams as the 300 tempest GM. Part # 12353918.
They rated:
214º / 224º @ .050”
.295” / .310” lobe
.442” / .465” Valve
112º Lobe Sep ) with closed exhaust

Quote:

Originally Posted by EDT (Post 4676714)

so, this cam ?
Grind Number:CS XM 278H-12

Intake Duration at 050 inch Lift:234

Exhaust Duration at 050 inch Lift:244

Duration at 050 inch Lift:234 int./244 exh.

Advertised Intake Duration:278

Advertised Exhaust Duration:292

Advertised Duration:278 int./292 exh.

Intake Valve Lift with Factory Rocker Arm Ratio:0.498 in.

Exhaust Valve Lift with Factory Rocker Arm Ratio:0.500 in.

Valve Lift with Factory Rocker Arm Ratio:0.498 int./0.500 exh.

Lobe Separation (degrees):112

Grind Number:CS XM 278H-12

Cool. what heads did you end up getting?

Are you going to do something with your exhaust?

She should be a runner for sure.

I found this video of a small block with that cam in it idling.......NICE!

I didn't know that the LT1 came from the factory with a forged bottom.....nice motors.

Post up a couple pictures of your boat when you get a chance.

Look forward to seeing how this comes out.

Thanks,
Russ

I went with the ProComp 190 / 64 heads. Yes I know I will have a lot of cleaning up to do on the ports and bowls but I have more time then money. Wish me luck !!!!As to the exhaust I will deal with that if needed Again wish me luck!!!!