Cam questions, converting to roller

[eddielugnutz]

I'm converting a non H.O. motor to roller, and to the H.O. firing order, I was going to go with the roller conversion kit in Texasmustang.com, the one that screws in the lifter valley with the the spider pan to hold the roller lifters in place, question is, can i use the stock roller lifters in a older non roller block, or does the block have to be machined for roller lifters?

Second question is about cams, can I use a roller cam with the hydraulic flat tappet cam bearings that are in the motor? are the journal diameters the same, or do I have to get new cam bearings for a roller H.O. motor to fit the roller cam?

If the block needs to be machined for roller lifters and new cam bearings, then i will choose to stay hydraulic, but are there any companies that make hydraulic flat tappet cams with the H.O. firing order, i'm using the fuel injection so I know I need to keep the same firing order, but the older non roller non H.O. 302's have the different firing order,

thank you for your time and advice!

[82 GT]

Not sure about question #1 but I know you need to do something to use roller lifter on a non-roller block....I forget......
Second, you can use the same cam bearings you have.
Third, the cam grind dictates the firing order.

It might be easier to find a roller block at the junkyard instead of buying extra part to retro-fit the roller cam/lifters.

[Gearhead999]

I have used several of the retro-fit Crane kits. The lifters came with the cam and the pushrods were a special length. Other then that it went right in without any problems. One of my kits had the spider, the other had tie bars links attaching two lifters.

[Ieatcamaros]

The lifter bores are the same. No machining required to do the swap. Except for drilling and tapping the lifter valley for the lifter spider. If you want to stay with the hydraulic flat tappet cams, just get one for a 351W. Your motor will never know the difference. The H.O. firing order is the same as the 351W. When looking at comp cams, the ones with the "35" prefix are 351W and H.O. firing order and the ones with "31" have the old 302 firing order.

[bmxmon]

Check out the new "Mustang and fords" magazine, (January 2006) There is an article where they build a 289 for a sunbeam tiger and instal a roller cam with spiders and whatnot. I would also check through Hotrod.com's tech articles, there is alot of information there.....

[~The Jester~]

I'm building an engine for a friend, and am doing this same exact thing. ONLY thing we ran into when doing the swap, is you need a small base circle cam. Ford's "alphabet" cams won't work.

Stick with one of the "kits" as mentioned, and you should be fine.

[Unit 5302]

The kits come with special length lifters because the lifter bosses are deeper in the HO roller block. The cam bearings are also different.

Classic Trucks article on small block Ford

221/260/ Early 289

Although the 221 served duty as a reliable grocery-getter and was never known as a performance engine, the 260 and 289 engines changed how small-block Fords were viewed, first in the Falcon Sprint and later in Hi-Po Mustangs. These early engines can be identified by their unique five-bolt bellhousing pattern.

Late 289/302

The small-block that solidified Ford's reputation for performance was the Hi-Performance 289 4V. Produced from 1963-67, its distinctive idle, and the cacophony of its mechanical valvetrain coupled with ferocious rear tire shredding potential, made its presence known. However, of all the small-block engines Ford has produced, the most popular and frequently modified are the 302, or the 5.0L, small-blocks.

Introduced in 1968, the most desirable of these for street rod use are the hydraulic roller tappet engines. First seen in the '85 GT Mustangs, roller blocks have taller lifter bosses, and the cam bearing bores are bigger to accommodate the shaft's larger diameter bearing journals and base circle. But the real icing on the cake came the following year when electronic fuel injection was added. Unquestionably, for street rod applications, these are the most desirable of the Ford small-blocks.

[eddielugnutz]

Ok, screw it, i'm going hydraulic flat tappet, why? because I really don't care, I'm only interested in making around 350hp, it's a freshly rebuilt 302 .30 over with TRW 9:1, forged rods, I wanted to run Trick Flow twisted wedge heads, Trick flow reccomended the stage 1 cam for my application, i was using the above motor with manual,4.10 gears, they also said that the trick flow heads on a stock shortblock could only run a maximum of .540" lift and with 9:1 compression only use up to 225degrees of duration @ .05", I was going to stick hydraulic flat tappet and use a cam of equivelant specs, i was looking at COMP CAMS Magnum series cams, part # 35-414-3, specs: 270degree duration, 224degrees at .05"lift, .500/.500" lift 110degree LSA, it seems that this cam is of almost identical specs as the Trick flow stage 1, I understand that it's comparing apples to oranges from roller to non roller, but am I correct do you think in my cam choice, does this look like a sufficient cam for my application, I think it's pretty conservative, but I'm not greedy,

If I am sticking flat tappet, i guess i have to order matching non roller pushrods that are a bit longer than the roller ones right? I have to run hardened for the Trick flow heads with guideplates. I guess the choice for lifters will be easy now.

Let me know what you guys think, I apreciate all your time and advice!

[82 GT]

I think the cam is a little on the conservative side, like you said.
Honestly, if you like the Comp Cams, I would look at the 280* Magnum or their XE series like the 284XE. I have the 274XE in my engine and I think that's not enough for my setup. I should have have 284XE also or maybe the 294XE.
A tech guy from Comp Cams told me the 274XE cam is more aggressive than the 280 Magnum because it has more aggressive ramp rates than the 280. I was also told that Ford engines like duel pattern profiles that favor the exhaust side.
Since you're going to have adjustable valvetrain, why not consider a solid flat tappet cam? You'll make a little bit more power with properly matched solid cam than with hydraulic.
I made the mistake of porting and polishing my stock heads without spending the extra money on converting to adjustable rockers so that I could run solid cams. I guess if I did that though, I would be better off buying a set of aftermarket heads.......