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For the 305 Crowd: Engine Power Channel

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Old Apr 11, 2026 | 11:04 AM
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For the 305 Crowd: Engine Power Channel

Spoiler:
460 HP!

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Old Apr 11, 2026 | 06:37 PM
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Re: For the 305 Crowd: Engine Power Channel

I guess I'm the 305 crowd. The large increase in compression with the domed pistons in the previous video produced a big gain in HP. Now this video's addition of the solid roller cam and Trick Flow 175 heads added another 100 HP, up to 460, from 350+. It's a huge cam, larger than most people would consider putting in their 350s, so the result is a testimonial to those heads.

Unfortunately, searching Summit and Trick Flow websites, it looks like those heads aren't available anymore for a 305. They appear to only be available with 350 valve sizes (2.02/1.6) and combustion chambers. I searched sometime last year for them too, and they weren't available then either, so EP/PN must've gotten those 1.94/1.6 heads a while ago, which takes the airflow out of the sails of 305 owners today.
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Old Apr 12, 2026 | 09:47 AM
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Re: For the 305 Crowd: Engine Power Channel

There's you and a few others around here. I've been part of the 305 discussions and once you get past the detractors, there's some decent information exchanged.
That said, yeah, I'm a little surprised that the Trick Flow offering has disappeared. I poked around a little this morning and about the only (but not the only) manufacturer that came up was World Products S/R 58 cc head. Directed at the circle track crowd (which explains it's iron casting), at 225 CFM, it looks to have some potential.

https://billmitchellproducts.com/pro...3fXJUmuoA0oNSW

I think that CFM is comparable to the L30 Vortec head. Speaking of which, they are still out there too.

Edelbrock has their Performer RPM series but there's a caveat to using them on a small bore engine.

https://www.edelbrock.com/performer-...YniGDx2nkixwAT

As for the cam, it's the linchpin in any build. For any small displacement engine to make top shelf HP, RPM is involved though. 7000 isn't that much really although Engine Power going there with a stock bottom end is a recipe for disaster. Even they acknowledged that.
But it shows what can be done. 400 HP out of 305 is a simple formula. An L30 head with a .500" cam, along with the requisite induction and exhaust would do it. And I found 400 HP to be plenty of fun, and 12 second capable as well.
FWIW, my former stock bottom end 350 (albeit with ARP rod bolts), went tens of thousands of miles and saw 6500 regularly.
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Old Apr 12, 2026 | 09:28 PM
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Re: For the 305 Crowd: Engine Power Channel

Originally Posted by skinny z
7000 isn't that much really although Engine Power going there with a stock bottom end is a recipe for disaster. Even they acknowledged that.
But it shows what can be done.
I couldn't believe it. I think they went to 7200 RPM on the 305....I was CRINGING! I thought it was going to blow. When engine masters did "how much boost can a stock bottom end take", on an L31 Vortec, I believe, I was cringing when it got above 500hp....I think it went all the way to 700. But THIS...this was high RPM for stock parts and especially stock rod bolts. Man....I can't believe the thing held.
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Old Apr 12, 2026 | 09:38 PM
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Re: For the 305 Crowd: Engine Power Channel

Originally Posted by Tom 400 CFI
I couldn't believe it. I think they went to 7200 RPM on the 305....I was CRINGING! I thought it was going to blow. When engine masters did "how much boost can a stock bottom end take", on an L31 Vortec, I believe, I was cringing when it got above 500hp....I think it went all the way to 700. But THIS...this was high RPM for stock parts and especially stock rod bolts. Man....I can't believe the thing held.
I can kind of hoping for a rapid escape of those stock bits...It would make for great YT content.
Fully agreed on the 7k and stock parts. No thanks.
That said, throw in some relatively cheap Eagle rotating components and if the circle track guys have any input here, the SIR rods I have in the 357 with the less than premium ARP fasteners are proven to be higher HP and higher RPM stalwarts. I'm betting on that being true because my lump is going to see 6500 at least twice on every pass. Maybe three times if I have to step up the gearing!

Last edited by skinny z; Apr 12, 2026 at 09:43 PM.
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Old Yesterday | 02:13 PM
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Re: For the 305 Crowd: Engine Power Channel

That whole series has been interesting to watch, I think. By series, I mean all the 302 Vs. 305 videos they have done.
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Old Yesterday | 04:12 PM
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Re: For the 305 Crowd: Engine Power Channel

7200 RPM on the 305
:shrug:

Same crank as a 350. Why not?

My money says the EXACT SAME $$$$$, whatever they were, would have made 528 HP in a 350; or over 600 in a 400. Meaning, spending that whole SHIPLOAD on a 305, is a WASTE OF MONEY, unless you're in some sanctioned racing class that has a 5.1 liter hard upper limit. If all you want is to go fast, that's not how to do it the best way.
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Old Yesterday | 04:27 PM
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Re: For the 305 Crowd: Engine Power Channel

Originally Posted by sofakingdom
:shrug:

Same crank as a 350. Why not?
Because there is NO WAY in hell I'd go 7200 RPM on a 350, either! Not one that I wanted to drive home, with.


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Old Yesterday | 04:33 PM
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Re: For the 305 Crowd: Engine Power Channel

Well, yeah, butt if all you were doing was looking for 460 HP on a dyno so you could write a magazine article that would please all the 305 nut huggers and leg humpers, and tempt them into impulse-purchasing a copy at the AZ counter, why not?

Last edited by sofakingdom; Yesterday at 05:17 PM.
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Old Yesterday | 06:10 PM
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Re: For the 305 Crowd: Engine Power Channel

Originally Posted by sofakingdom
:shrug:

Same crank as a 350. Why not?

My money says the EXACT SAME $$$$$, whatever they were, would have made 528 HP in a 350; or over 600 in a 400. Meaning, spending that whole SHIPLOAD on a 305, is a WASTE OF MONEY, unless you're in some sanctioned racing class that has a 5.1 liter hard upper limit. If all you want is to go fast, that's not how to do it the best way.
It's not the crank that concerned so much as it was the stock rod bolts. I'd be willing to wager that after a few of those passes there would be obvious signs of distress upon a teardown inspection.
As for the waste of money. Yeah. Sure. Kinda. But the racing classes aside (I'm suuuuure you're aware how fast a 305 3rd gen Stock class drag racer can go). Yes, FAR more to it than engine, but still. Those guys buzz those things to the moon. Not entirely sure of the reinforcements allowed though. But stock does mean something.
But yes, if all you want to do is go fast, as I did in my late 1970's tech college years, I followed my engine course professor's advice. "If you want to go fast on the street, then put the largest engine you can between the fenders!" So I built a 400. Pretty quick too for the day.
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Old Yesterday | 06:21 PM
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Re: For the 305 Crowd: Engine Power Channel

I just want to take my 305 and run down my buddy with the 1990 5.0 Mustang GT. We are playing the 90s OBD1 HP games. LOL
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Old Yesterday | 06:26 PM
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Re: For the 305 Crowd: Engine Power Channel

Originally Posted by Tom 400 CFI
Because there is NO WAY in hell I'd go 7200 RPM on a 350, either! Not one that I wanted to drive home, with.
Waaay back in the day, (before I had that aforementioned 400 SBC), a racer once told me that they'd have their junkyard 350, race and rev the living **** out of it. When, not if, it blew up, back to the junkyard for round 2. Or round 3, 4. Nothing new I guess.
But that's not my deal. Blowing stuff up is hard on the wallet! The 400 eventually let go. That though was the result of a sustained 6000+ RPM open road blast that, judging by the result (a persistent misfire that I couldn't diagnose) floated a valve, bent it then that valve head eventually snapped off. I was left with one cylinder head, an intake manifold/carb and that was it. Everything else was totalled. That's what happens with stock parts (as in valve springs) and the valve head makes the piston disintegrate and the rod enters the block at an acute angle. That was the end of hot rodding for the better part of twenty years.
Yes, I like to drive home.
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Old Yesterday | 06:29 PM
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Re: For the 305 Crowd: Engine Power Channel

Originally Posted by sleeper84
I just want to take my 305 and run down my buddy with the 1990 5.0 Mustang GT. We are playing the 90s OBD1 HP games. LOL
I think the key there is not to be afraid of RPM!
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Old Yesterday | 06:38 PM
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Re: For the 305 Crowd: Engine Power Channel

Originally Posted by sleeper84
I just want to take my 305 and run down my buddy with the 1990 5.0 Mustang GT. We are playing the 90s OBD1 HP games. LOL
Those games are fun. Back in the day, I had my '83 LG4...it went low 15's w/a cam. Meh.
My bud had an '86 Z28, LG4/5 speed. He had a mild compu-cam, Edelbrock headers and Performer intake, it went pretty damn good. He and I were driving home one night from somewhere, going south on 495 (A couple of Mass-holes) and a late '80's/early '90's 5.0 comes up on us, I knew immediately, that I was "out". But my bud down shifted his Z28 and he and the 5.0 went for it. I tried to keep up as best I could to watch/see, and it was a dead heat. Totally cool! Everyone slowed and the Mustang guy hollers out his wondow to my bud, "305 or 350?!" My bud replies, "305!". He got the nod of respect and we all parted ways. Fun times. Fun cars.

Last edited by Tom 400 CFI; Yesterday at 06:43 PM.
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Old Yesterday | 07:28 PM
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Re: For the 305 Crowd: Engine Power Channel

Originally Posted by skinny z
I think the key there is not to be afraid of RPM!
With the factory LO3 heads and cam, I'm not afraid of 4500 RPM. LOL. I'm trying to find A set of LB9 heads (still not amazing I know) and a L31/LT4 cam. I have a L98 on the engine stand that I've considered swapping in but I kinda wanna stick with the 305 just because....

Originally Posted by Tom 400 CFI
Those games are fun. Back in the day, I had my '83 LG4...it went low 15's w/a cam. Meh.
My bud had an '86 Z28, LG4/5 speed. He had a mild compu-cam, Edelbrock headers and Performer intake, it went pretty damn good. He and I were driving home one night from somewhere, going south on 495 (A couple of Mass-holes) and a late '80's/early '90's 5.0 comes up on us, I knew immediately, that I was "out". But my bud down shifted his Z28 and he and the 5.0 went for it. I tried to keep up as best I could to watch/see, and it was a dead heat. Totally cool! Everyone slowed and the Mustang guy hollers out his wondow to my bud, "305 or 350?!" My bud replies, "305!". He got the nod of respect and we all parted ways. Fun times. Fun cars.
We've been to the track a couple times screwing around. We were playing with his and put on a belt just turning the water pump, pulled the air filter (his engine is already pretty hashed), pumped the front tires WAY up and even iced the intake down in the staging lanes for 15min before his last pass of the night. We'd have smashed his fuel pressure regulator a little with a hammer if we could have found a socket the right size for a little extra fuel on top end during WOT Open Loop.

It was a really fun night and I'm sure everyone else thought we were nuts.
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