Offshoreonly.com

Offshoreonly.com (https://www.offshoreonly.com/forums/)
-   General Q & A (https://www.offshoreonly.com/forums/general-q-20/)
-   -   525 Edelbrock head (https://www.offshoreonly.com/forums/general-q/341390-525-edelbrock-head.html)

F-2 Speedy 09-21-2016 10:11 AM

525 Edelbrock head
 
Does anyone have the specs on these, valve, combustion chamber, runner size, how well do they flow. Could you compare them to an AFR ??

Baja Rooster 09-21-2016 11:19 AM

I have no idea which head that is, but my Performer RPMs flowed at .700 lift in335 and ex244

mike tkach 09-21-2016 10:20 PM


Originally Posted by 33outlawsst (Post 4483584)
Does anyone have the specs on these, valve, combustion chamber, runner size, how well do they flow. Could you compare them to an AFR ??

pretty much aluminum version of a gm rect port head,not remotely close to a good afr head.

getrdunn 09-21-2016 10:24 PM


Originally Posted by 33outlawsst (Post 4483584)
Does anyone have the specs on these, valve, combustion chamber, runner size, how well do they flow. Could you compare them to an AFR ??

Read up on them months ago. Conclusion was there were designed to merc specs and nothing special. Thought they were 310 runner. I was gonna use them on some long blocks to sell but decided not to.

mike tkach 09-21-2016 10:34 PM


Originally Posted by getrdunn (Post 4483859)
Read up on them months ago. Conclusion was there were designed to merc specs and nothing special. Thought they were 310 runner. I was gonna use them on some long blocks to sell but decided not to.

pretty sure the only thing different from the non merc head is the exhaust bolt location on two bolts holes,that way merc thinks they can sell replacement heads.

SB 09-21-2016 10:44 PM


Originally Posted by mike tkach (Post 4483862)
pretty sure the only thing different from the non merc head is the exhaust bolt location on two bolts holes,that way merc thinks they can sell replacement heads.

Yup. that makes it proprietary. And thus mega money. LOL.

F-2 Speedy 09-22-2016 06:08 AM

I bought a pair of 525 long blocks assembled, Im wanting to make 600 ++ hp from these with a Vic jr. intake and a 850 carb is that reasonable ?

Would a different off the shelf cam be better the same springs ?

SB 09-22-2016 06:50 AM

I think a good estimate will be near 570 -580hp. From what I've seen the AFR's should put in another 30hp or so.

Here is some flow data on the 315 Edelbrock Performer RPM heads.
http://www.airflowresearch.com/bbc-shootout/

PS: if you get fixated on the hp/tq #'s on this article, remember it's got a solid roller and just use the power #'s to compare the heads.

sutphen 30 09-22-2016 08:25 PM

dart now has a cnc'd head for the 525 I believe.

MILD THUNDER 09-22-2016 09:21 PM


Originally Posted by sutphen 30 (Post 4484213)
dart now has a cnc'd head for the 525 I believe.

http://dartheads.com/dart-product/pro1-24-525-mmr/

SB 09-22-2016 09:56 PM

33outlaw, if you don'thave the 525exhaust, then you can use any head and use and performance bbc exhaust.

If you keep the 525 heads, you can get the Stainless Marine 525 conversion exhaust to keep it cheaper than being stuck buying the 525 CMI's.

sutphen 30 09-22-2016 10:09 PM


Originally Posted by SB (Post 4484243)
33outlaw, if you don'thave the 525exhaust, then you can use any head and use and performance bbc exhaust.

If you keep the 525 heads, you can get the Stainless Marine 525 conversion exhaust to keep it cheaper than being stuck buying the 525 CMI's.

or drill and tap a few holes.

F-2 Speedy 09-23-2016 07:21 AM


Originally Posted by SB (Post 4484243)
33outlaw, if you don'thave the 525exhaust, then you can use any head and use and performance bbc exhaust.

If you keep the 525 heads, you can get the Stainless Marine 525 conversion exhaust to keep it cheaper than being stuck buying the 525 CMI's.

I got the exhaust with the boat, CMI big tube sweepers, tails and mufflers, cool collar and drilled for both bolt patterns

F-2 Speedy 09-23-2016 07:48 AM

I got a great deal on these long blocks, I was just wondering if the Edelbrock head would support 600 ponies, I don't need big power to make this boat run, its documented with 500hp a side @ 87mph,


All times are GMT -5. The time now is 06:29 AM.


Copyright © 2026 MH Sub I, LLC dba Internet Brands. All rights reserved. Use of this site indicates your consent to the Terms of Use.