Cylinder Heads/Intake

[chautauquasun]

Looking to maybe try to get a little more out of my 351w performance wise but not sure if it is worth it. I have a 1984 Supra Rider with 351W engine that runs strong. Was thinking about upgrading my cylinder heads and intake to try and get a little more out of the old 351 but not sure I can get that more out of her with just redoing the top half of the motor. I don't want to do a full rebuild with new pistons etc.

Is it possible to get a few more ponies out of the engine by upgrading just the heads and intake or is really not worth the money. I have looked at oldl performance heads on Craigslist but not sure I want to go with something that may not work. Looked at packages on summit and Jegs but again, not sure there is enough bang for the buck with out changing the cam and pistons. I know if I am going with the stock pistons that I need a smaller value style head. I would probably contact the head mfg and see what size they would recommend.

Anyone on here gone this route before and sorted out the parts that work best? As always, performance parts for Ford are always more expensive than chevy and the added cost for only a few more HP may not be worth it. Let me know what you think.

thanks
Dan

[michael hunter]

IMO The more power you try to get out the more unreliable the engine will become. What are you looking to improve low end pull or top speed? Have you checked into a prop change?

[crystal waters]

We [QUOTE=chautauquasun;130966]Looking to maybe try to get a little more out of my 351w performance wise but not sure if it is worth it. I have a 1984 Supra Rider with 351W engine that runs strong. Was thinking about upgrading my cylinder heads and intake to try and get a little more out of the old 351 but not sure I can get that more out of her with just redoing the top half of the motor. I don't want to do a full rebuild with new pistons etc.

Is it possible to get a few more ponies out of the engine by upgrading just the heads and intake or is really not worth the money. I have looked at oldl performance heads on Craigslist but not sure I want to go with something that may not work. Looked at packages on summit and Jegs but again, not sure there is enough bang for the buck with out changing the cam and pistons. I know if I am going with the stock pistons that I need a smaller value style head. I would probably contact the head mfg and see what size they would recommend.

Anyone on here gone this route before and sorted out the parts that work best? As always, performance parts for Ford are always more expensive than chevy and the added cost for only a few more HP may not be worth it. Let me know what you think.

thanks
Dan[/QUOTE




You could go with a pair of GT-40 heads.
Some feel Dart heads would be even better.
That said , i agree with Michael. You are chasing an older engine with large dollar parts and the end result may not be all you are looking for.
Talk to Ski Dim as they sell the GT-40 heads and can best advise you.

[cadunkle]

I'd be looking at Trick Flows, ready to run in a mild engine for about $1300. need to check piston compression height and dish on the PCM 351w, maybe someone else knows, but I'd wager the end result is from the factory they are in the 8:1 - 8.5:1 compression range. Going to a ~60cc chamber should get that closer to 9.5:1 which opens doors for far more power and efficiency.

Roller rockers, not sure what's out there for small blocks these days though.

You'll need a modern cam to make any appreciable improvement. A cam change is not a big deal, particularly if you have the top end off the engine anyway. I might go with something like a Comp 35-235-3, which is a 254/262 on a 111* LSA. That should give a broad torque curve, smooth idle to avoid reversion, and modern more aggressive lobe profiles to maximize flow.

Edelbrock performer intake will be fine for lower RPM. It's basically an aluminum version of the factory 4v intake but that's all we really need for this application.

Holley 650 4150 would be the carb I'd go with, probably a vacuum secondary for this application.

[Salty87]

...Have you checked into a prop change?

Cost wise a new prop will be your best bang for the buck unless of course you've already upgraded from an old one.

[cadunkle]

OP said he wanted more power. A prop change is horrible bang for the buck if that is goal. prop change is a tradeoff and compromise. Granted going to a CNC prop with more surface area from an cast prop with less surface area is an improvement overall as it will reduce slip.

[cadunkle]

Anyone on here gone this route before and sorted out the parts that work best? As always, performance parts for Ford are always more expensive than chevy and the added cost for only a few more HP may not be worth it. Let me know what you think.

Not accurate. SBC and SBF are basically the same engine design. A few minor advantages for SBF in the early engines that Chevy improved upon in the newer SBC variants. Cost to build a comparable SBC and SBF is effectively the same.

As for Ford being more expensive to build or HP per dollar. I'm not even sure there is a significant difference in cost to build a BBC vs a 385 series anymore, but 385 series wins hands down in platform design and max effort applications. BBC is an inferior platform.

BBC vs FE though, there is more FE aftermarket support than there was but the platform is quite limited as compared to the 385 series both in max output and you won't get as much HP per dollar. I love the sound of an FE though, and they have a place in in restorations or among the Chris Craft crowd.

For what it's worth, whenver the 454 in my Saltare needs major work it will be replaced with a 385 series, probably a mild 545 stroker.