525sc's Rebuild
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I am doing a complete rebuild on 96' 525sc's. All new internals, Dartcast iron heads, cam, etc. Need suggestions. What size heads and cam? Looking for aprox 75-100hp. Can not do intercoolers. Anybody have any success putting reliable power into these motors?? Motors r being done locally on Long Island.
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There are people on here who are a lot more expert than me but, from what I have read on OSO: Don't increase the boost with that blower without adding an intercooler. It is a Weiand 177 and will cause to much intake heat. You may want to sell that one and move up to a 250 or even a 420 mega blower.
The AFR 305 heads seem to be the way to go. With a good porting job, you won't need to raise the boost any. With a good roller cam, that combo should give you what you are looking for.
The AFR 305 heads seem to be the way to go. With a good porting job, you won't need to raise the boost any. With a good roller cam, that combo should give you what you are looking for.
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JC, i do have somebody to do the assembly. basically buying all new, sending out the block, etc for bore, balance. Also plan on having them dyno tuned. i am sure you have experience with these motors. Any suggestions would b appreciated.
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Install Crane 741 hyd roller, upgrade to B&M 250's, dual Nickerson/Holley 750's and add 5 1/2 psi boost = 600+ TRQ & 600+ HP. Baby the bravo's and it will be reliable. Idles at 750rpm with max hp around 5400 rpm. B&M 250's have the same height as the Weiand 177's.
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Here's an old thread about cam choice. Cam choice will also depend on the flow numbers of the heads you get.
http://www.offshoreonly.com/forums/s...w%2Fwieand+177
I put the Crane 731 cam in my 525SC last Spring. It was the only performance upgrade I made. I picked up 50 -100rpms on the top end over the stock cam. I am/was running 7lbs of boost with no cooler. I did a top end refresh last Spring and everything looked fine.
If you are not boating in salt, I would go with aluminum heads.
http://www.offshoreonly.com/forums/s...w%2Fwieand+177
I put the Crane 731 cam in my 525SC last Spring. It was the only performance upgrade I made. I picked up 50 -100rpms on the top end over the stock cam. I am/was running 7lbs of boost with no cooler. I did a top end refresh last Spring and everything looked fine.
If you are not boating in salt, I would go with aluminum heads.
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thanks Griff, .. Heads, carb jetting, cam. I ill be keeping the stock 525sc carb, intake mani, 177 blowers and crank. Block will most likely be 30 over. My head is spinning...nite nite
Last edited by iamfaster; 11-15-2004 at 06:40 PM. Reason: add info
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I have used the 741 in a blown 454 with 420 mega blower with great results..690hp on dyno @ 5psi. A good friend used a similar comp version with 174 B&M and dominator carb on a 454 @ 7psi , dynoed 675hp. Both these engines had 8.5-8.75 compression and ported square GM heads with larger valves. I like the added static comp especially with the smaller blowers. The first engine mentioned going on 6yrs and over 250hrs, lots of oil changes and timing never over 30deg total also now at 7psi boost. Just my .02, good luck.