89 Baja Force 235 "Used Parts" Mild Blower Motor Lake Boat Project
#41
IIRC, the Edelbrock oval ports were essentially the same heads used on some of the crate GM engines, which were more of a "roval" or rectangle / oval hybrid design. This means it actually has a bit larger port than your 781's, and not as much of a mismatch. Also, some rectangle intakes have a smaller cross section area than many GM rectangle heads. Just things to consider.
Like I said before, my interest in changing heads is really related to loosing weight. The port miss match, increased flow i.e. potential for more hp/torque, and reduced likely hood of detonation due to aluminum's heat transfer characteristics are all added bonuses.
Last edited by 89Force235; 12-22-2015 at 05:02 PM.
#42
Registered
The 781 heads aren't too bad weight wise. Pick up a Dart or Merlin cast iron BBC. Wholly schit !
You going to install the metal block off plate that came with the intake gaskets for the exhaust crossover port ?
How about a lifter valley tray ?
Both are cheap mods to keep some heat out of the intake.
You going to install the metal block off plate that came with the intake gaskets for the exhaust crossover port ?
How about a lifter valley tray ?
Both are cheap mods to keep some heat out of the intake.
#43
The 781 heads aren't too bad weight wise. Pick up a Dart or Merlin cast iron BBC. Wholly schit !
You going to install the metal block off plate that came with the intake gaskets for the exhaust crossover port ?
How about a lifter valley tray ?
Both are cheap mods to keep some heat out of the intake.
You going to install the metal block off plate that came with the intake gaskets for the exhaust crossover port ?
How about a lifter valley tray ?
Both are cheap mods to keep some heat out of the intake.
Concerning the heat in the in intake those are good comments.
There's no crossover port in a B&M 174 intake so it's "blocked" as is. Actually I don't think Ive ever see a blower intake with a cross over port but I could be dreaming....
I never thought of installing a lifter valley tray, that's a good idea.
Last edited by 89Force235; 12-22-2015 at 06:45 PM.
#44
Registered
Yes, the intake does not have the crossover port. Your 781 heads do. What's stopping the exhaust and it's heat going thru that port ? The intake ! The heat, the heat...repeat after me, the heat, the heat. LOL.
The steel plate will help block some from hitting the intake. If you wanna be trick, coat the steel block off.
Another cooling trick for the heads. Run coolant lines from rear of intake up to the t-stat housing.
Don't be a fraid to run a 120*F thermostat if you are running a t-stat.
The steel plate will help block some from hitting the intake. If you wanna be trick, coat the steel block off.
Another cooling trick for the heads. Run coolant lines from rear of intake up to the t-stat housing.
Don't be a fraid to run a 120*F thermostat if you are running a t-stat.
#45
Yes, the intake does not have the crossover port. Your 781 heads do. What's stopping the exhaust and it's heat going thru that port ? The intake ! The heat, the heat...repeat after me, the heat, the heat. LOL.
The steel plate will help block some from hitting the intake. If you wanna be trick, coat the steel block off.
Another cooling trick for the heads. Run coolant lines from rear of intake up to the t-stat housing.
Don't be a fraid to run a 120*F thermostat if you are running a t-stat.
The steel plate will help block some from hitting the intake. If you wanna be trick, coat the steel block off.
Another cooling trick for the heads. Run coolant lines from rear of intake up to the t-stat housing.
Don't be a fraid to run a 120*F thermostat if you are running a t-stat.
I'm not running a thermostat. Think I'll see much benefit from plumbing the rear of the intake to the thermostat housing?
Last edited by 89Force235; 12-22-2015 at 09:02 PM.
#46
Registered
You mentioned aluminum heads transfering heat better. I'm giving you ways of removing heat much better from intake and all heads on the BBC.
BTW: poor mans coating the exhaust heat block's off's is finger paint ultra black to intake manifold side of metal block off's. Remember to use the solid block off's, not the one's with holes in them.
BTW: poor mans coating the exhaust heat block's off's is finger paint ultra black to intake manifold side of metal block off's. Remember to use the solid block off's, not the one's with holes in them.
#47
Registered
7.5#`s of boost?!
174 blower?
ouch.
174 blower?
ouch.
#48
#49
That's a nice set up! As much as I'd like to see my turd of a boat get into the 80's, I'd honestly be thrilled at this point to break 60.
Care to share how much boost the 177 make on a 496?
Also, as long as you are sharing, cam specs and WOT rpm?
Thank you!
Care to share how much boost the 177 make on a 496?
Also, as long as you are sharing, cam specs and WOT rpm?
Thank you!
Last edited by 89Force235; 12-23-2015 at 08:58 AM.
#50
I know, I know, I know, the general consensus here is:
174 = junk,
177 = ok.
But please give me the benefit of a doubt, there is only whopping ~1.6% difference in overall displacement between the two blowers. If I'm seeing excess heat with the 7.5 pulley I'll dial back the boost. The pulley I have is what I got with the blower when I bought it.
174 = junk,
177 = ok.
But please give me the benefit of a doubt, there is only whopping ~1.6% difference in overall displacement between the two blowers. If I'm seeing excess heat with the 7.5 pulley I'll dial back the boost. The pulley I have is what I got with the blower when I bought it.