351 OE Cam / 302 H.O. Cam

Topic: 351 OE Cam / 302 H.O. Cam (Read 2256 times) previous topic - next topic

351 OE Cam / 302 H.O. Cam

January 25, 2014, 08:59:00 AM

Has anyone used a 351 cam in a 302? I looked at the journal specs in my Haynes manual;

302 Number 1 journal diameter is listed as 2.0805 to 2.815 inches (journals 2 - 5 are similar)
351 Number 1 journal diameter is listed as 2.0815 inches (journals 2 - 5 are listed the same way with only the high limit listed.

I have a 1980 reconditioned short block with H654P pistons. The block is bored .040 over.
I plan to drill and tap for the roller lifter hold down.
I have a complete H.O. upper and a set of E7 heads I had built for the H.O. cam.

The 351 cam is out of the 1995 Truck 5.8 I rebuilt for my F-150. Machine shop checked it and said it is good.

The real question is... what is the difference between the OE 5.0 H.O. Cam and the OE 5.8 Cam? And are they interchangeable?

351 OE Cam / 302 H.O. Cam

Reply #1 – January 25, 2014, 09:50:03 AM

Quote from: Utahan;427877

The 351 cam is out of the 1995 Truck 5.8 I rebuilt for my F-150. Machine shop checked it and said it is good.

The real question is... what is the difference between the OE 5.0 H.O. Cam and the OE 5.8 Cam? And are they interchangeable?

The truck cam is a wimp compared to a HO...

302 & 351 cams are interchangeable, but I don't think it possible to use the OEM roller cam & lifters in a pre '85 5.0 block as the lifter bores are too short...

351 OE Cam / 302 H.O. Cam

Reply #2 – January 25, 2014, 10:15:35 AM

Yup. Only way is with a retrofit style kit. Those have reduced base circle cams. Either that or a link bar style setup. Still Have to machine the block for the hold down.

351 OE Cam / 302 H.O. Cam

Reply #3 – January 25, 2014, 12:15:01 PM

Abd some GT40 heads will make more power than E7's. Even ported E7 heads will barely flow more than a stock GT40 or 40P set.

Change the springs on the '40s and use them, along with an HO cam.

I'm curious what lower you're going to use in a 351w that an HO upper will bolt to...? I want to see that.

351 OE Cam / 302 H.O. Cam

Reply #4 – January 25, 2014, 02:32:51 PM

I am building a 5.0 not a 5.8. Was just curious about using the 5.8 cam.

351 OE Cam / 302 H.O. Cam

Reply #5 – January 25, 2014, 02:48:25 PM

V8Demon, By machining the block, you mean drilling and tapping for the spider hold down right? I do have an HO cam and a set of dog bones with the computer (A3M) out of a 92 Mustang. I just cant find the dog bones and planned to install the spider out of my Tbird 5.0.

351 OE Cam / 302 H.O. Cam

Reply #6 – January 25, 2014, 04:47:30 PM

I fixed the previous post. My typing skills have been atrocious as of late. I left out a part of 2 sentences and combined them. I do it quite often on this laptop, but I normally catch myself. Anyway, click the article link: http://www.mustangandfords.com/techarticles/engine/1307_roller_camshaft_conversions_engine_upgrade/

351 OE Cam / 302 H.O. Cam

Reply #7 – January 25, 2014, 05:57:25 PM

Quote from: Utahan;427908

V8Demon, By machining the block, you mean drilling and tapping for the spider hold down right? I do have an HO cam and a set of dog bones with the computer (A3M) out of a 92 Mustang. I just cant find the dog bones and planned to install the spider out of my Tbird 5.0.

With the short lifter bores of a std block, the dog bones will set so far down they will bottom on the lifter flats... Instead of resting flat on the block, they will be rocking back and forth on the lifters...

You're either going to have to go high $$$ small base circle cam, or stick a flat tappet in it...

351 OE Cam / 302 H.O. Cam

Reply #8 – January 25, 2014, 08:41:31 PM

My suggestions; roller block ('86 up Tbird/Mustang etc-trucks were NOT roller block until around 94 or so)

HO cam will have more power than a 351w cam, unless it's an aftermarket speed part. And I still stand by my GT40 head suggestion over the E7's. Better flow, and probably even more common in the junkyards these days.

351 OE Cam / 302 H.O. Cam

Reply #9 – January 25, 2014, 09:52:06 PM

Quote from: ThunderbirdSport302;427935

My suggestions; roller block ('86 up Tbird/Mustang etc-trucks were NOT roller block until around 94 or so)

HO cam will have more power than a 351w cam, unless it's an aftermarket speed part. And I still stand by my GT40 head suggestion over the E7's. Better flow, and probably even more common in the junkyards these days.

BUT most truck blocks from '85 were roller, only needed the hold down bosses to use the roller cam... I had one of these '85 E5TE blocks, it's been passed around among three friends and myself...

351 OE Cam / 302 H.O. Cam

Reply #10 – January 25, 2014, 11:03:37 PM

I'm confused. I'm pretty sure all 5.0 blocks are roller capable after 86... my 85 block is.

I'm guessing you ment 351 blocks?

351 OE Cam / 302 H.O. Cam

Reply #11 – January 26, 2014, 09:52:25 AM

Excellent article. Thanks!

I have a complete HO Tbird built 08/90 that I was planning to keep original and rebuild the engine... BAD KNOCK in the engine. Anyway I think it will become a donor for my 87. Just can't let go of the 87, it has the sequential tail light kit that I don't think is available anymore.