Why bother?

hound dog · #1 (**permalink**) 03-05-2003, 08:16 AM

I've watched the posts here for some time about people going to the trouble to stroke a 302. If you're building a cobra, why go to the expense of stroking a 302 when you can just buy a 351? Fits in the same space, and you don't have the stress of the extra stroke on the block. I don't see an advantage even if you already have the block. Anybody?
h dog

wilf leek · #2 (**permalink**) 03-05-2003, 08:43 AM

Maybe, if you already have a 302 in your Cobra, and want some extra HP, you want to keep the existing headers etc?
Surely it is cheaper to rebuild (and stroke) an existing 302 than to go out and buy a 351, and renew all those parts that no longer fit/work?

Just a thought

Excaliber · #3 (**permalink**) 03-05-2003, 10:08 AM

One other reason might be weight, I think the 351 is about a 100 pounds more. Now myself, I understand your logic, I'd go with a 351 if starting from scratch. If not, I might stroke my 302 (or whatever while I wait for more h.p.......)

einrE

hound dog · #4 (**permalink**) 03-05-2003, 11:25 AM

I can see Wilf's point ref. already having a 302 in the cobra. I wouldn't want to change headers, motor mounts, etc. to change to a 351. I agree that would be a toss up. Especially in a mustang it might be almost impossible to make it fit. But to start from scratch on a new cobra, I just don't understand it. Just for looks maybe on a FIA?
h dog

Pete Munroe · #5 (**permalink**) 03-05-2003, 08:55 PM

I am using a 65' 289" block primarily because 5 years ago I thought I had to have a 65' or earlier block to squeeze through smog laws in California.

There is now a new bill in CA that allows 500 per year "kit cars", ie: you built it... vehicles to be registered as the year they were completed and meet the smog laws of the YEAR THEY REPRESENT!

Never in my life did I think anything good could come from Sacramento, the capitol of the left coast.

I am now a "built in 2002, smog exempt 1965 Cobra"...and the 65' block wasn't necessary. Arggggh!

That said, the 289/302 weighs a little less than a 351, and is about an inch lower profile.

I don't think the weight is 100 lbs less than a 351, more like 30?, but I may very well be wrong.

Can you guys check on real bare block weights....289-302 vs. 351 ?

So, with every bolt on item aluminum, I have a little lighter engine than the same in a 351, but probably not more than 50 pounds.

In a 289" car, I wanted handling over warp speed, so it will work for me untill I discover I am Ken Miles reincarnated...not likely!

The lower profile of the 289" lets me run a high rise and full 3 inch tall aircleaner without a hood scoop...I have a ERA 289 FIA, without the hood scoop, still room to spare, but a 351 high rise has to have the scoop I think..although with air horns shaved off a Holley maybe it would clear.

I am a little concerned about side loads on the block in theory, but I have a 6k chip in the MSD, and hope it's not a problem.

Time will tell!

If it blows in open track, I will try a 302 Sportsman block, or an unbored 302 if they are still available, whatever!!!

Have fun.

Pete

Excaliber · #6 (**permalink**) 03-05-2003, 09:44 PM

I heard that "rumor" about a full dress 351 weight compared to a full dress 302 being a 100 pounds difference. It does sound like a lot, but I wouldn't be surprised. I would think a lot of the weight difference would be in major areas like crank, flywheel and heads.

Hadn't thought about the lower profile! Good call, lower center of gravity also, and THATS good for handling! For me, handling FIRST, power second.

Ernie

JWheaton · #7 (**permalink**) 03-05-2003, 09:52 PM

Wilf,

For crying out load stay on your side of the pond and stop trying to create the next great debate on this forum.

The Small Block -- versus -- the Ever, But Just Slightly, Smaller Block

wilf leek · #8 (**permalink**) 03-06-2003, 03:12 AM

Hi there Jwheaton

I believe the appropriate phrase is, um, let me see....... ah yes:

BITE ME!

hound dog · #9 (**permalink**) 03-06-2003, 07:57 AM

Giggles and grins all around. Actually I got my 351 (393) into the Unique with a single plane Edelbrock intake and a dropped base Moroso 3" air filter. Not a hell of a lot of room to spare but works fine. Now the oil pan is just about as tight to the pavement as I want to see it (Milodon). Anyway, I'm pretty happy with the setup. I've seen all kinds of numbers quoted for engine weights and I don't know how many of them I trust. Checking in the Ford racing catalog I don't see anything but length, width and height dimensions given for the small blocks. You have a 1.3 inch difference in deck heights, maybe a little in crank weight and intake weight, but it doesn't seem like 100 pounds.
h dog

wilf leek · #10 (**permalink**) 03-06-2003, 08:21 AM

h dog - I am really restricted on my car for height under the bonnet (sorry, hood). Had to stick with a performer rpm for that reason, even though my engine spec would benefit from a Vic Jnr.
Have toyed with the idea of machining about 3/4" off the carb mounting platform on the Vic Jr, to make it fit, but since the dual plane rpm inlet gives me great street manners (well, not me exactly, I have very poor street manners, but the engine, if you see what I mean), I think I'll stick with it for now.

The other side of an engine mounted that far up is great ground clearance - with a shallow but widened sump for oil capacity, I have nothing lower than the actual chassis tubes. Chassis on my car is a la Kirkham - twin tube jobby.
No idea what it does for CofG tho' - track handling is not a priority for me.

kdavies3 · #11 (**permalink**) 03-06-2003, 08:55 AM

HI Wilf, I've missed your wit and wisdom on the UKCRC site recently.
it's good to see you're still active in the forums though.

wilf leek · #12 (**permalink**) 03-06-2003, 09:11 AM

Kev - no-one said I had died, just gone away. LOL

Excaliber · #13 (**permalink**) 03-06-2003, 09:44 AM

Wilt,

Manners in your Cobra? Would that indicate your not driving around "naked" these days?

Ernie

pderouss · #14 (**permalink**) 03-06-2003, 10:45 AM

Wilf.

Another contribution from this side of the pond.

I had a Vic Jnr. in my previous Cob which caused significant problems in finding an air cleaner low enough to clear the bonnet (hood). It gave great performance at the top end but made the engine very lumpy and unresponsive until the revs hit 3500. Then a combination of the secondaries and the manifold made it feel like a turbo had kicked in.

I'm not sure if you got my e mail on Ralydot mountings as my home system is very erratic. Could you try me on pderouss@ford.com as this is very reliable. (lets not use this as an excuse for the Ford v Chevy battle that seems so prevalent on the CRC site!)

wilf leek · #15 (**permalink**) 03-06-2003, 11:04 AM

enrie - nope, it's too cold for bare-a$$ driving just now, but come the summer........

Pderouss - I have forwarded my original email to you to that new address. Don't fret about Ford vs Chevy here. It won't happen. Only poor misguided Brits get into that one, and I don't play anymore.
Now - big block vs small block - there's a topic!! Or maybe rivets.

Thanks for the comments about the Vic Jr - that was my suspicion anyway about driveability, glad I went the dual plane route.

pderouss · #16 (**permalink**) 03-06-2003, 11:19 AM

Wilf.

Look forward to seeing the shots when I get to work tommorrow. BB vs SB is an acceptable discussion in the US where most of the roads are straight (and wide) and gas is cheap. In Europe an SB is the only option. As for rivets, I must admit I went out to the gagage and counted mine when that one came up! By the way they were 14 each side plus a centre one.
Shal we try the "should the stripes be tapered" one or has that already been aired here?

Mr.Fixit · #17 (**permalink**) 03-06-2003, 11:26 AM

To me, if you have the money for a new: crank, rods and pistons to stroke the 302. than the extra money for a new block $150 +machining you would need to do anyway, intake manifold and distributor isn't all that great, you would probubly be buying them ayway. But if you really want it to look like a 289, then you need the short deck windsor block so no 351 for you. There is some fun in misrepresenting a big motor for a little one. sure, it's a 289 (347), any big block chevy I will ever own will wear 396 badges, even if it is 540+ inches.

Dan Stryffeler · #18 (**permalink**) 03-06-2003, 02:11 PM

Simple, I blew up my 289 and had a lot of pieces/parts left over to shave some of the cost off a new motor.

I actually wanted to have a 289 built, but on the builders reccomendation, went to the 302/347 build. His quote; "There's no substitute for cubic inches".

Also, the othe big driver in the decision was that I had the tri-power induction which I wanted to reuse.

All told, probably saved a pretty good buck on the build-up.

- Dan

Pete Munroe · #19 (**permalink**) 03-06-2003, 09:40 PM

Gang,

I looked up block weights in the Ford Motorsports catalogue, 1999. See the post "302 vs. 351".

The difference between a 302 and a 351 bare block is at least 75 lbs...add the weight of a 3.00 inch journal crank over a 2.24 inch journal crank, it should approach 85 pounds...???

Hey, does any one out there have good weight figures for full engines...please do apples to apples, aluminum whatever to the same. Hard to find the numbers.

So, the difference I think is over 75 lbs, approaching 90lbs...a bag of cement on your front end.

In a car for the street, ??? who cares...in a high power drag car the not a factor, in a track car, maybe a good thing, if you know how to use it.

Dollars? A stock 351 has got to be less expensive than a stroked 289/302, no contest there.

Have fun!!! Split hairs!!! If we didn't, we wouldn't be judging the pros and cons...and having fun. These forums are a kick in the pants, makes us think.

If you aren't a hard core racer, I doubt if much of this really matters, but it sure is fun!

Pete