Reply With Quoteif you decide to sell it send me a e-mail
thanks pat(slotracer)
ok motor builders. i need some info. i pulled a 454 out of my 91 GMC 4x4 duelly to replace it with a 502 crate motor. i dropped the pan on the 454 and noticed it is a four bolt main. are these engines workable in a mild form for a jet boat? i may be able to pick up a set of marine edelbrock heads cheap, but really wouldnt want to spend all the money for a new rotating assembly. (crank, rods, forged pistons) as it is i would need a cam, lifters, the edelbrock heads, and intake. new pistons i can understand as im sure id want to bore it once. but is it worth all the expense to get this block useable? i know of someone who took a stock bottom end ford 460 and put nice heads and cam and its running fine at 5000 RPM. what sort of RPM can the stock BBC bottom end handle? keep in mind this is to replace the 455 olds so i would also need all the other item for the swap. is this engine worth the off season project? the olds is still running hard so its not a must do at this point.
if you decide to sell it send me a e-mail
thanks pat(slotracer)
You have a good start with that block "the 4 bolt is a plus" to build a good solid and mild 500 HP motor pretty cheap not countng the heads.
Which Edlebrock marine heads are they, Oval or Rect. Port? Hal...
actually i have a choice on the heads. friend of a friend hook up sort of thing. if i could get 500 HP cheap from it id be a very very happy boater. the motor had the 2 barrel fuel injected valve body on it and im pretty sure the heads are very small valve and small port. so i would think the edelbrocks are a must. my main concern is the short block. will the crank, rods, and stock pistons handle 5000 (or close to) RPM ? a roller cam would be nice, but expensive. though im not sure a roller cam fits in the block without machining. the 454 had about 150K miles on it. ran good, just needed more pulling power so i switched to the 502. i would imagine the pistons are cast. are forged a must in a marine motor?
I'd have a mind to build the 4 bolt a little better and leave it in the truck.
Strengthen up the 502 and put it in the boat.
Since that probably doesn't sound appealing, you can put the whole Edelbrock package (heads, cam, lifters, springs, intake, on the 454 short block and get over 500hp. The low end rotating assembly is said to be good to about 600hp so you should be safe.
The only thing is I'd definitely get it all magged before putting it all back together.
I'm going thru the same thing right now with the 4 bolt main. The machine shop doing all the work said he'd trust the stock stuff for about 550hp but that's about his limit.
Thing is, it's not like the boat is being driven at 5500 rpms for any real extended length of time
with that block, crank and rods you have a good start. I ran a stock LS6 at 6500 rmp for a while then geared the boat and ran for 2 seasons at 6200 rpm. with that many miles, pull it apart, see if it will hone without getting to much clearance or bore and put in some hypereutectics pistons. the pistons are only $36.00 ea in jegs.
make sure the machine shop checks the rods and they are still usable as well. I have had realy good luck w/ the BBC my self. By the way I have a set of GM square port heads and a tunnelram w/ 660 center squirters for ya.
well thats all ecouraging news, thanks. i am doing some serious thinking on the swap, but it will definatly be a winter project. ( now how am i gunna get the boat and engine to glamis and find time to work on it?)
im sure id bore and get new pistons so that wasnt much concern. more so was the rods and crank. but i think it will be just fine. and yes of course getting it all checked before hand is a must.
ill have to do some research on the heads. i do like the idea of wieght savings with the aluminium, but im not sure if that would be the best way to go. i also like the idea of the edelbrock package ( heads, cam, lifters, springs, ind intake) since i do get a deal. but im not sure if the cams they offer are suitable for jet boat applications. again, more research.
now that the possibity of the swap is there i have so many other items i am going to need. mounts, coupler (H-bar), jet boat oil pan, and for the exaust id like to try the lightning headers. would like to stay with thru transom.
what are you asking for the heads, tunnel ram and carbs? a tunnel ram isnt a must for me, but it sure would look cool.
"what are you asking for the heads, tunnel ram and carbs? a tunnel ram isnt a must for me, but it sure would look cool."
Your right, the tunnelram is all show in your aplication. I would take $650 plus shipping if it was purchased as a package. the heads are not put together right now, they need new valve guides and springs. OR $900 for both and you can have my other 990 square ports (only 5 hours since fresh my the shop). each head is 35lbs more than aluminum for your info, also you create more power w/ cast. (they stay hotter in the combustion chamber making a bigger boom). the biggest advantage to aluminum, other than weight, is you can run a little more compresion on pump gas. I run 10:1 on pump w/ these heads and have run 11:1 on pump w/ octane boos w/ these heads without ever detonating anything.
Hope this info helps and if it can save you some $$$$$$$. let me know. I may have other BBC stuff as well that may help on the conversion..
at this point i am still doing the research. dont want to jump into it too quikly. though the heads and tunnel ram would be nice. and im sure they are a good deal. and if you still got em when i know i can afford em ill hit ya up. thanks for the info too. now its time to add the stuff up that im gunna need.
Dennis Moore wrote a very informative book called (BIG-BLOCK CHEVY MARINE PERFORMANCE)HP Books.
You can get or order it at any good book store. It is really good. It just might be the best $16.95 you've spent lately.
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