Budget 454 Build
12-16-2014, 05:56 PM
#11
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That truck LE8 smog engine, in stock form circa 1985, used a 800CFM quadrajet if memory serves me right.
Rated at 230HP at 3600RPM. 385ft lbs at 1600RPM. Dead at about 3800RPM cam.
The "marine" version of that engine, simply got a larger camshaft, no real changes to the long block.. The cam, Which was simply the old GM LS5 camshaft. Used in the 350HP 396ci, and the LS5 454 engines from thlate 60's early 70's. 214/218* with .461/.480 lift, 115lsa. That cam is about dead at 4800RPM.
Like I said, that stock RV cam would need to be the first thing to go in the trash.
Rated at 230HP at 3600RPM. 385ft lbs at 1600RPM. Dead at about 3800RPM cam.
The "marine" version of that engine, simply got a larger camshaft, no real changes to the long block.. The cam, Which was simply the old GM LS5 camshaft. Used in the 350HP 396ci, and the LS5 454 engines from thlate 60's early 70's. 214/218* with .461/.480 lift, 115lsa. That cam is about dead at 4800RPM.
Like I said, that stock RV cam would need to be the first thing to go in the trash.
12-22-2014, 08:47 AM
#12
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My plan is to re-ring, replace the bearings, swap to a double roller timing chain, and swap the cam and valve springs. Its a very low hour motor so im hoping to reuse the stock rotating assembly. I have an oval port Weiand Stealth intake that im considering port matching the heads to. What do you guys think about this practice? Im really shooting for maybe 400hp and do not intend on spinning it past 5000rpm. Also would anyone like to recomend a cam?
My boat had one of these rebuilt truck blocks in it. Guess what happened one day? Boom. A little extra heat on a cylinder and it went.
Also, if you do re-use the hypereutectic pistons, make sure your ring gaps are on the high side. If the ring ends even lightly touch each other, those pistons are gone.
12-22-2014, 08:58 AM
#13
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Be very careful, especially if it's not a completely stock rotating assembly. The cheap rebuilds people use for trucks /rvs use hypereutectic pistons instead of the cast used in Mark IV Mercs and Chebbies. They will not take much punishment like a cast piston, and not at all like a forged piston.
My boat had one of these rebuilt truck blocks in it. Guess what happened one day? Boom. A little extra heat on a cylinder and it went.
Also, if you do re-use the hypereutectic pistons, make sure your ring gaps are on the high side. If the ring ends even lightly touch each other, those pistons are gone.
My boat had one of these rebuilt truck blocks in it. Guess what happened one day? Boom. A little extra heat on a cylinder and it went.
Also, if you do re-use the hypereutectic pistons, make sure your ring gaps are on the high side. If the ring ends even lightly touch each other, those pistons are gone.
12-22-2014, 09:18 AM
#14
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12-22-2014, 09:29 AM
#16
Hey guys i'm looking to squeeze a little more power out of my 454 for next summer. Im looking to put together a reliable set up without breaking the bank.
I have a 24' Banana 454 TRS set up currently running 54mph gps in the chop. I'm spinning a 23p Mirage at 4500rpm.
My current motor is a 1991 454 4-bolt main truck motor out of a Winnebago. It is all stock, smog cam and everything except for a Marine DUI distributor, a couple carb spacers and a 850cfm marine double pumper. I'm also running a Stainless Marine exhaust. The long block is very similar to a Merc 330. It has penut port heads, cast crank, and i belive 7.8:1 compression.
First let me say that im thrilled that the boat even made it past 50mph with this motor! It has been super reliable for the past two seasons but i would like more for next season. I would be happy with a solid 60mph.
My plan is to re-ring, replace the bearings, swap to a double roller timing chain, and swap the cam and valve springs. Its a very low hour motor so im hoping to reuse the stock rotating assembly. I have an oval port Weiand Stealth intake that im considering port matching the heads to. What do you guys think about this practice? Im really shooting for maybe 400hp and do not intend on spinning it past 5000rpm. Also would anyone like to recomend a cam?
I'm really looking to just get some respectable, reliable speed for next season without killing my TRS. Im finishing up my degree and paying tuition in cash so my funding is a little tied up at the moment! Next year is a different story, this is a one season motor and after that its just a spare. So what do you guys think???
I have a 24' Banana 454 TRS set up currently running 54mph gps in the chop. I'm spinning a 23p Mirage at 4500rpm.
My current motor is a 1991 454 4-bolt main truck motor out of a Winnebago. It is all stock, smog cam and everything except for a Marine DUI distributor, a couple carb spacers and a 850cfm marine double pumper. I'm also running a Stainless Marine exhaust. The long block is very similar to a Merc 330. It has penut port heads, cast crank, and i belive 7.8:1 compression.
First let me say that im thrilled that the boat even made it past 50mph with this motor! It has been super reliable for the past two seasons but i would like more for next season. I would be happy with a solid 60mph.
My plan is to re-ring, replace the bearings, swap to a double roller timing chain, and swap the cam and valve springs. Its a very low hour motor so im hoping to reuse the stock rotating assembly. I have an oval port Weiand Stealth intake that im considering port matching the heads to. What do you guys think about this practice? Im really shooting for maybe 400hp and do not intend on spinning it past 5000rpm. Also would anyone like to recomend a cam?
I'm really looking to just get some respectable, reliable speed for next season without killing my TRS. Im finishing up my degree and paying tuition in cash so my funding is a little tied up at the moment! Next year is a different story, this is a one season motor and after that its just a spare. So what do you guys think???
12-22-2014, 09:36 AM
#17
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12-23-2014, 05:22 PM
#18
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that short block runs good leave it together. once you push pistons out of a bore you can't justify reinstalling dished pistons. mebbe replace the bearings without removing crank. scare up a set of alum heads with 113 cc chambers and you will be in high 8's CR.
01-01-2015, 11:49 PM
#19
Registered
vortec heads. l29 engine. 100cc chambers large oval ports with ski jump in the intakes. cheap easy to find in boneyard. a little port work and they do 440 or so hp. 500 ft/lbs torque.
01-02-2015, 08:51 AM
#20
Charter Member #927
Charter Member
I may have what you need. 1991 454 mag parts that will all be coming off. Heads, pistons, rods, Crane 242 cam and lifters. I also have a
Wieand Stealth intake manifold. /then you may still be able to use your carb.
Wieand Stealth intake manifold. /then you may still be able to use your carb.
