302/351 Ford OE blocks - how to make them live even at 1000 hp 

The guy knows what he’s talking about. My little turbo 306 inch SBF has been at he 540+ RWHP for over 14 years with hundreds of trans brake launches at the drag strip. The block crankshaft and connecting rods are 100% OEM FOMOCO. The devil is in the details.

I’ve enjoyed reading his books through the years and really enjoy getting to actually listen to him.

You can spend years going to college/Uni to learn these things. DV is the teacher using his decades of experience. Experience, practical, LISTENING and talking to those who have been down that road far outstrips any other method of learning.

Several things I'd like to add (if I may!), at the 600+ power level, it's a good idea to convert from external balance, to internal balance. This reduces the harmonic forces considerably! With external balance, you have the weights at each end of the crank. At high RPMs and high loads (nitrous and forced induction) those weights tend to "whip" the crank lengthwise which causes more stress on the already thin main webbing. So not only does the crank have the vibration and torsional twist that it normally has, then it's got that whipping effect along its length also. Converting it to internal balance eliminates those weights and brings everything much closer to center....like very close to the main cap bolts, which is the strongest place in all of the block! By eliminating the whipping effect, you're eliminating the very force that is trying to wiggle the main caps back and forth. Along with the block mods that Mr. Vizard is showing, one could have a 1000 hp stock block that could live all day.

Your secrets are safe with me!!!! Priceless knowledge and I thank you

Thanks David, I've been a fan of your content since the 90's when I purchased your "How to Build Horsepower" book, that's when I started to understand how things work. Thanks for a lifetime of knowledge, Steve

There is always so much to be learned from this channel. Thank you, David.

Thankyou David 😊 your are a wealth of valuable knowledge, sharing your life's experiences should keep the knowledge of you and everyone you've learnt with alive for ever, true gentleman

Awesome tips & tricks not to mention the Supliers / Builders / and or modifiers. Thanks.

Very good at sharing your connections with other professionals.

Thanks again for your knowledge, hope you had a great Christmas and wishing you and your loved ones a great and prosperous New Year

Great information, it would be cool to see the revised block perform 👍

Interesting in your videos how you take something that best describe above my pay grade and break it down and explain from start to finish. Thank you

Fascinating! Thank you Mr. Vizard!

Very informative video David. Thanks for sharing the information. I have used the steel girdles with no issues. Important to line Hone when changing to studs and girdles, IMO. I like the looks of the aluminum girdle. Thanks again. Take care, Ed.

I always had a thought that the girdle design should not only tie the main caps together but mount to the oil pan surface all the way around the block as one large piece

Thanks for all things SBF 👍

Amazing info, as always!

It’s all about proper machine work when prepping a block.

Not Déjà vu this time.. excellent 👍

Excellent video sir

Thanks DV for another excellent SBF video! When planning the engine build for my '85 Foxbody, I looked at all the mods that can be done to my stock 5.0 roller block for strengthening and longevity. I also considered the cost to do it AND also the cost of all the parts that I was putting into the block. (Callies crank & rods, Mahle pistons, coated bearings, custom grind roller cam) After considering all the pros/cons of using my OEM 5.0 roller block, I decided to 'bite the bullet' and buy a Dart 8.2" SHP block with a 4.125" bore. (helps unshroud the AFR 195 valves and gives me 6.0 liters!) It did cost more to build it with the Dart block, but I was already putting a LOT of money into the engine. Now I can sleep at night with a truly bulletproof 363cid SBF.

Thank you David!

Great information! I hope to see and learn any info on .460 ford

I had a 69 boss 429 block & the main caps would still walk even though it was for bolt maine 546 ci with 300 hp N.O.S shot Still had chatter and main cap walking problems Then I was lucky enough to find a new S.V.O 460 block $1200 Problem solved I sold that engine to a friend of mine who in turn sold that block for $ 8000 Somebody was looking for a numbers matching block. And they were willing to pay that much just for the block. The block had been bored out to the max. And they still bought it

Great video thank you

Hopefully this isnt the cam vid 🤣😅 just kidding DV😁👍 Cant wait to see this vid.

Thanks DV

Thank you David!! Again you have provided comprehensive and undeniably reliable positive expert information!

The Mexican block 351ws in my experience are much better than the American ones. A few years ago a friend had a 427w stroker on his '89 fox mustang, PRW main belt, H cranks etc, he was running 11 lows, upon reaching 10.70, if anything 2 passes, the block snapped in half, never I use nitro. Curiously, they had just given me a block 351 (Made in Mexico) year 89, I conditioned it and put it together, the car ran constant at 10.70 at the beginning, then we improved the suspension and removed the c6 trans and put a powerglide with transnbrake. The car improved and was running steady at 10 lows, many passes and finally we decided to use a 175hp sohot nitro. The car ran 9.40 many times...finally after 4 years of banging on the street and track a metal from a conrod failed causing one of the conrods to break and destroy the main mount and hit the block. . When I took it apart to see the damage, I was surprised that if the block had not been hit by the broken connecting rod, everything else was in place. the block did not fail at all.

Can’t wait for the 3000hp turbo big block!

Nice to know 🤙🏼

525 bbc... 2500-3000 hp....woooooooooooah nelly i wanna hear more!

I’ve got a 1989 mustang with the stock block that came in the car and it’s been running 600 wheel horsepower for the last 15 years and 30,000 miles using a Paxton blower with a TKO 600 transmission behind it the motor is fully built but that stock block is there and hanging in just great Edit: yes she’s main girdled and been through the machine shop for a stage two race prep

Having built a couple of 5.0 versions of a 302 to 3.4" stroke the Ford machining is quite good and the black and crank seems to better metalurgy than the early 70s engines which in the distant past I have also built. The oiling needs for the oil out and oil in need to be modified, and radius the corners in the top of the block, Screw in plugs too are nice. And fix the oil returns to the pan. Inadequate factory. The stud girdles are essential on stock blocks and caps. Alloy ones are not ideal as they expand differnt than a 1/4" steel one. ARP studs are a given. Having had issues with Clevo lumps pulling the block out of shape with 1/2 studs it seems the 7/16 is probably superior. Always enough on a Chev!! Grouting to the welch plugs is essential. I do like the idea of reinforcing the vally as you have done. My current engine is using a forged 3.4"Scat crank, the iron ones flex too much on a big power engine. Though perfectly ok for a nice street engine. And ofcourse Scat 5.4" rods. AND I am using CHI 208CC Windsor modded Clevo heads. So the best part of 600 hp is expected. N.A ofcourse,, hair dryers are for girls!! Road race engine. Which must be a production block. Though it seems a Supercar SVO block is ok!!. Though not by the rules. And there is none available anyway!! Solid roller cam, agressive but not super agressive. And the block is bored only .010 with custom pistons for the heads.Nothing is top dollar stuff but everything should be fine for half hour max races. And 7500rpm. Though for all the Ford tragics, yes you can get good power out of a baby 8.2 deck engine. But it will never be a Chev. Though is smaller and lighter. But the Chev is smaller and lighter than a 9.2 or 9.5" block Interestingly I know of a Boss 302 style engine [3" stroke'] that turned over 8000 in a speedway sedan for many years. Power was adequate and the car was fairly light. [Pantera] The other thing too,, 302W firing order breaks engines, 5 litre uses Clevo firing order that saves engines

This sounds a lot like the issue Cosworth had with their 4cyl before they went to v6. With windsors i've always run a girdle.

In diesel engine world like Cummins ISX engine caps will wear into the block. They have ring dowel that fix fit block and cap but they still vibrate under load. The fix using gasket eliminator to keep oil out of mating surfaces. Reason oil help caps to move which wears the block. Paccar engine main and rod caps are fractured there's no movement with them

9:50 I remember someone reinforcing the lifter valley on a Buick 455 with metal and epoxy for the Engine Masters challenge. It made good power too.

Im interested in hearing more about this concrete in the water jackets..🤔

If I were doing a stock block. Half the water jacket filled with hard block, screw in freeze/soft plugs, and stud girdle.

David is certainly one of the best in the business. Having said that there is NO OEM block that will take 1000hp ever and that includes the original boss block. This is with every possible strengthening mod done to them. When exceeding the 450-500hp mark, move to an aftermarket block.

I don't have what it takes to get a block machined like that, but if I did I would save and buy a better one to begin with.

On any engine build you need to watch for core shift

David got a question. Just how beneficial is it using 351 Cleveland heads on a small block 289/302 ? Back in my day I always played with small block fords. Sm Chevy had a hard time with my mustang. I ported my own early cast heads and built eng.loose.. rev like a sowing machine. Best key to Ford it must breathe.

David I have several of your books and recently discovered your videos. I'm curious if you ever done any work with Pontiac engines ?

I've seen loads of guys with broken small blocks from nos turbos etc. I don't trust any stock sb past about 500 to 600 hp.

Morning David . I have just bought your book “ Port and flow test “ ive not read it cover to cover but what I have read is very interesting . I have a question ,I have a race car ( Formula Vee 1300 ) we Have to use a restrictor plate ( 36mm hole ) on the induction side . We are using Weber 40s ( IDF ) and everyone bolts the carb directly onto the restrictor plate . I have watched many of your videos on RU-vid, based on that I think the restrictor plate should be nearer the intake port ! valve seat is 31mm in diam with a valve head diam 33.1 . Standard port is cast 28ish diam although the inlet port ( Siamese ) is a mess . I seem to recall you saying there is no point in having a bigger inlet port than the valve ? ( hope I remember correctly ) if this is the case would it be more efficient to taper the inlet manifold from “40mm”at the carb down to 31mm where it bolts to the inlet port ? Is there an optimum taper / length for best port velocity ? Motors run about 100BHP cam comes in about 4500RPM and tops out at 7500RPM however there are guys on the grid that rev to a little over 8000 and have significantly more power so I know there is more to be had . Great videos , very informative I only wish I was in the states so I could attend one of your seminars . Regards Andy ( UK )

Engine plate will help on splitting the block for a fact

lots of amusing comments here criticising anyone who builds a hot 322, like why bother. Maybe because they want to see how far they can go? Anyway it's cool to get an old school engine performing, particularly in it's original car. And not everyone races straight line or has to win.

Do you ship your block to them or buy one of theirs to get the bessel main caps

When we built engines to take this kind of power id say keep it at a lower rpm. Fill the block part way with filler. Run a plate mount, run splayed main caps. Use a stud girdle, and keep rpms under 7000.

How about a 3 valve F head engine? Should get the best breathing, and high RPM?

Have you noticed less head gasket issues with the girdle? I've been told that the head gasket issues with higher power 302 builds is caused by the block itself flexing under the heads, and that was getting near the point of block failure.

I was wondering your opinion on main girdles. Would a good steel girdle work on a 2 bolt main Chevy? My theory is that locking the main caps together significantly reduces cap walk and controls vibration better than going to 4 bolt mains. Plus a girdle is a lot less than a 4 bolt main conversion. Am I close? Thanks for sharing!

Dave what are your thoughts on 1965 289 HP. ? Are they any good? My Tbucket has one in it now.

Blocks split in the valley often david

How about a 351 worked to 366 with comp ratio 9.83:1 stroke 3.600" bore 4.030" what do think

So how does the wind age tray fit in all these mods?

,,,,,,,,,,,David , you need to put all your SBF building knowledge into a book.......The books out there were published decades ago .....and no better than a service manual.......Imagine a Dart block with Jay's cap mods and the rest................three stage nitrous capability.........mega money !!!!!!!!!.

Was the 2 bolt converted to a 4 bolt at the end of the video? Cementing isn't a new thing . The valley try is also not new . Seen both of those before

The 302 and 351w blocks really aren't comparable in terms of strength though, as the 351w blocks can already handle much more power than any 302 block.

Does sustained high-revs do these in, like 7+ thousand for extended periods??

David never works with cadillac 500 blocks and engines. Why. It has great advantages over other blocks. Bloodviking

Can't wait to see how vizard makes this possible! A 302 roller making 1000hp reliably? Mabe a modern 5.0, I've split a 93 302 completely in half making less than 600

That's alot of work to step that block.

NM I replayed it and it was fine

The four bolt mains are a good idea. Is there enough meat in the block to splay the outer bolts? I've heard that the splayed caps on Chevy small blocks are stronger than the factory four bolt items.

Harmonics are an issue, even the 4 cylinder BDT that they tried to use in F1 had a similar thing going on....

I'm wondering if the beloved Chevy small block can suffer these cracking issues with a big power increase? , or Chrysler small blocks? Also , I remember after I'd re painted my Hemi 6 cyl (Australian) motor it was noticeably quieter , I suppose because the extra thickness of paint dampened vibration.

If it is a mains issue I have a solution, I've been designing a system that can be used on any engine that will strengthen the mains using only two bolts per cap. It has been used before in some very high end super cars but I'm sort of retro fitting the idea to other engine designs.

Cadillac blocks can take loads of boost , or nitrous

Most racers know all the tricks. Block fill Steel caps Stud girdle Valley brace Arp studs

How did he get 525ci from a stock 454 production block? I thought 498ci was about max out

No production casting 302 block after 1975 is going to live at 4 digit power levels. Dart, World Products, Ford Motorsport block, OK. *Maybe* a C9 "Hecho en Mexico" casting, *maybe* . No way is an E casting block living at even 800 hp.

We don't use stk caps. Lol. Bloodviking

Problem with this idea guys is. You put all the money and effort into what he's saying and you should have started with a thicker stronger aftermarket block. Bloodviking, master engine builder

Prw griddle for my sbc didn't fit without cutting and welding and the hardware was apparently a lead alloy nut, straight garbage in my opinion.

Missing alot of audio

Try 1000 hp on a stock 4 bolt sbc

Core shift is also a concern. Sonic check the block and don't over bore it.

The amount of money converting a factory block to 4 bolt, upper "girdle", main girdle etc.. you might as well just get a nice dart and go 4.125 without issue....

302 caps walk

Steel beats aluminum

Bulls***!!!!! I've seen him with 550-600 at the end of the quarter mile you stopped to get your ticket and your oil pressure drops to zero rev it up a little bit comes back you're on your way to breaking the block in half.

This idea is really not wise to begin with. David admitted he destroyed loads of factory blocks. It's just better to go with a stronger 429 or 460 block. A 302 factory block is not worth the effort as you will want to get more hp out of the engine later on and will be at the limit of the block. Why set yourself up for failure. And the work involved and the disappointment from an engine that you are waiting for it to let go after every high hp run.

Why would you even consider building a stock OEM Windsor block to some ridiculous power? That block is a thin wall component and just will NOT handle that power level. Or at least not for long. Cast crank ??, main caps too light duty ?? By the time you get done with machine work and high buck specialty parts (steel crank, cross bolting, and so on) you have surpassed the cost as well as the reliability of a Dart or similar after market item. Limit to 400 or so Hp with few good parts and machining and you have a good street and occasional strip engine.

What's a buck car. He wrote it.

These builds are making an engine survive on the ragged edge of failure. Why waste time money effort into something that is going to fail after a few runs, or you are waiting on failure. You can't enjoy it then. Bloodviking

Cap walk.....

I think the word you were looking for was "earmarks". Also, in the video side note @3:52, you state: "our super low buck car" - "beat the previous years champ's pro-built car" - Now come on DV, you don't really think anyone watching this doesn't already see you as a "Pro" in this area, do you? Your car may very well be a "low buck" car, but it was built by a pro, none the less (or at lease had guidance from a pro). I'm not insulting you, just an observation from the outside (actual non-pro) World!

Hencho en mehico, junk

Some Forgotten History... Ford cast a new 351w 9.2" deck sbf xe race block in 1966 (XE 93532) which got to just over 400CI in 1969 for Can-Am racing. This is were the later "351C" got most its spec's from when B knudsen pushed his own "Oldsland" inspired version through screwing up the 351W blocks development... goo gle "351w xe block" for more info.

Mexican blocks were never said to be stronger

Why go through all this work when you can just get a 351 Windsor and be done. Once I had my first 351 Windsor I will never go back to a 302 ever again. I buy as many 351 Windsor and Cleveland blocks I can find and 429 and 460 blocks also