The Classic "Best"

[Z24O]

i have a "fake" boss 302 in my 240.....in other words a 302 windsor bottom end with cleveland 302 heads and suitable aftermarket manifold.(and custom headers)......it is a fast revving motor that suits a light car,not as much torque as a SB chev though.

in australia it is a cheap performance option as we had the 302 cleveland over here both with 2V and 4V ports that allow the windsor bottom end to really breathe

paul

[Gollum]

351 and 302 use different pans. Stock 5.0 roller block splits at around 550-600hp. That would be with an excellent tune. If it is detonating it will die sooner.

 

 

You can ruin a 5.0 block at 500HP, but I've also seen plenty of 700+HP 5.0 motors. There's just alot more work to be done.

 

If you're looking for HUGE power, then the 5.0 motor isn't the greatest idea. But from what you've said you want I think the 5.0 is the way to go. Personally, I'd say go with a brand new block because the GT40 parts are much better and much more reliable. Plus the efi won't give you so much grief. And the best part about these motors is that power adders are widely prduced and well priced, so if the stock power isn't enough there's plenty of routes to go until you hit the 450HP range. Then you start looking at some serious costs, weather to get the 5.0 higher, or to put a different motor in entirelly.

[Guest c21brian]

I bought a 320 HP long block from Central Coast and it was the best $1995 I ever spent on my Z. I tried to beat the performance and cost and built a spare motor out of junkyard parts...after machine shop costs and replacement of worn out parts I still had an engine with a mish mash of used and new parts vs. the all new engine from Central Coast. Their crate motors are hard to beat.

[rudypoochris]

Also note, i think this is correct, the 351 is about 80lbs heavier then the 302. So basically the 302 is more common and lighter. Vs the less common heavier but stronger 351W. For me the 302 is perfect, I think if i were you i would buy the 3k 370hp central coast block you will be impressed.

[MusPuppis]

Pretty much agree with what all has been posted.

 

A 302 will be easier to find and cheaper to build though, so if your on a more restricted budget this motor would be the better choice IMO. Alot more is offered for it as well. Modding a 302 is.. well, cake.

 

Also, if you go the 302 route MAKE SURE you get it from an 88-92 Mustang. Ford whored the 302 out to a plethora of other vehicles but these are *not* the same motor. They are not roller blocks, many have different heads and intakes and they - in general - suck. Ford F-series available with the 5.0 have the same heads as the Mustang (Ford actually "lost" the castings they had planned to use for the Mustangs so they just jacked the F-series heads..) but the block and intake are different. The EFI system is also less than desirable.

 

I would avoid going with a Cobra motor unless you already have one as well. They can be a pain in the *** to get ahold of and often times the price asked makes it cheaper to buy a normal 5.0HO and just mod it yourself.

 

You will want to look in to upgrading the alternator as well. The alt used on Mustangs is a complete joke and extremely worthless. Major weakspot.

 

Depending on the route your looking to go, you can get various H/C/I kits through Summit and Jegs for the 302 that will, for around 2k, kick a stock 302 into the 300-350HP range with a mild cam. Very streetable, very mean. Trick Flow and Holley both have nice kits. I kinda like the TF better myself.

[Guest levelhead86]

I think it's pretty obvious the 302 is cheaper initally, and may possibly be overall... considering the real costs of transporting and machining that much more worth of engine *i.e. the 351w*. I've been doing american engines for a little while, and I'm by no means as experienced at ridiculous HP like most of you guys are, but I am VERY experienced with building speed on a budget, and from what I've seen, as high end as you go, I've never seen anything that told me there's anything cheaper than 302 parts... *while still staying Ford*...even high end 302 parts.

 

Nobody's addressed yet what the rest of the drivetrain is going to be like at "500HP+". Considering, if you're expecting 700HP or whatever, that stock rearend will turn the back of your Z into a helicopter in no time... If a Z with the major horses is like, your dream car, than go for it... but don't be surprised if you go well over the down payment on a new house, or a used lotus by the time you're done.

 

It's just my 2 cents I guess, but overall... unless you're planning on blowing a ton of money on a non-profit drag car, just stick with the 302 to start, and work your way up, because I know a few people who run that on the street with great results; and spent less than 2k on over 400HP.

[Guest moaiz]

Cheapest HP...Everything MusPuppis said. I just saw a complete, (serp accessories, upper intake, computer, etc) 90' 5.0 engine in the local paper for 600.00. Stock 225hp. Throw some coin down for a nice rebuild and you can use the info on http://www.fordfuelinjection.com/ to splice or build your own harnass or even order one from them.

[Guest hotdodge440]

How about a Mild 302 with a Paxton supercharger efi ?

[rudypoochris]

How about a Mild 302 with a Paxton supercharger efi ?

 

All depends what your style is and how you want your power to come out. I think 400hp with a paxton will equate to about the same cost in N/A for 400hp worth of upgrades. From what I have seen so far this seems to be true any way.

 

The charger would most likely have more torque, but since you spent all your $$ on the charger your redline would still be around 5.5k. More streetable for sure. For the N/A the same amount of money would probably be spent on H/I/C which probably would set you in the 6k-7k range for redline and most likely would shift your powerband up the rpm scale a notch or two, all dependant on what cam you use of course.

 

I think the N/A route is better though. If you go with a completely new block, seeing as you can order it with those performance parts already, whereas it is hard to find someone that will sell you a stock block with a paxton on it, alot of money can be saved getting you to the 400hp ish mark in about 3k and some. One would have to get the stock block and then by the paxton. I am not sure how much a paxton or K&B costs but I will guess atleast 3k, which would make the upgrade kind of crazy to me, as you would still be stuck with a used engine or have to shell out alot of $$$ for a new one in addition to the super charger.

 

 

EDIT: Just noted you said a mild 302 with a charger on it. HP wise I don't know what your shooting for, so I can't really say much. But it will most likely cost more then the N/A route up to about the 400/450 mark, after that go with the supercharger, but beefed up internals should be come mandatory.

[Guest 5ohphil]

While I will not sit here and downplay other advice, much of which is good, I have noticed some bad information. Anyway, let's clear up some details about 351's. I have one in my Mustang, so that's how I found some of this stuff.

 

The oil pan from a 302 will not work. The timing chain cover is the same, but the rear main cap is larger, hence, the 302 pan will not fit. Also, the deck height is taller. A 302 has a 8.7" height from the crank to the deck, 351's have either 9.2's or the more common 9.5's. The NASCAR boys run 9.2's. Because the heads are spread out farther, a 302 intake will not work. The heads from a 302 will bolt on and work with a 351 intake, but the chambers in the heads are really small and will limit high end power. 351 blocks are reputed to be able to handle much more power than a 302, however, the sad truth is that most people will NEVER break a 302 block, so let's not get ahead of ourselves.

 

The 351's are about an inch higher when all is said and done, making things much more cozy between the valve covers and the strut towers. Hood clearance and workablilty become issues. The 351 is a great motor for torque, however. My dad and I have similar top ends on our motors, the difference being that his is a .030 over 289 and mine is a 351. He drove my car and crapped his pants over the pull from the torque. If you can find a later truck block, they should be roller cam compatible.

 

On the subject of 5.0 blocks, the LSC, Thunderbird and truck 5.0 motors are all roller blocks from the mid-eighties on forward. I pulled an original motor from an '86 Bronco and it was a roller block. The blocks are fine. It is in the fuel injection and the cams and related hardware that the differences lie. Many of the non-H.O. 302's were either flat tappet or had very mild roller cams. But take the motor and put in a roller cam, lifters, spider and dogbones out of an H.O. motor and voila, you have an H.O. shortblock. I am not sure about differences between the heads off top, but if you want to make horsepower, bury the stock heads in your garden and buy some real heads in the aftermarket.

 

Just my 2 cents...

[rudypoochris]

5ohphil I agree with all of what you have said. Especially on the normal 5.0 being okay part, a slong as it is roller. The cam and heads are going to get chnaged anyway if you are going beyond stock, so it simply does not matter if it is a HO or a non-HO, unless the bottom end or osme internals are beefed up in a way I don't know?

 

About the other information though, I think pretty much everyone was in agreement, since hat was corrected, that the 302 pan does not match up to a 351 block, and that the deck height is increased making the engine taller and wider.