Stroker 351W .060” over?

[rocknhorse76]

Hey guys, I ended up tearing my 351W down due to excessive oil consumption. I built the engine in 1995, and it’s already .030” over. Machinist checked the bores and says it will have to go to .060” since there is quite a bit of a ridge and one cylinder has a small scratch in it. It’s a ‘74 block so he’s not worried at all about boring it that big. It’ll be a 4.00” stroke, so that would make it a 414W. I plan to use dished pistons with a CR around 9.5-10:1. Anybody have any REAL WORLD experience with a .060” over 351 block as far as reliability or overheating? I’m not interested in what anyone has HEARD or READ! Actual experience only please. And go….

 

[bronco italiano]

I refuse to rebuild any lock that would be .060" over. The risk, especially HP parts, and the costs of machine work/parts period, is not worth it. I would get a Dart block and be done with it. I am possibly in the same boat as you with my FE block, I told the machinist if it needs to me machine to .060 I will pay the 5,000 for a new block from Pond or BBM. And even then they still require some machine work.

 

[rocknhorse76]

The Dart block isn’t in my budget. Sorry, but not every Bronco owner out there is rolling in dough. Not looking to build a race engine or anything bigger than a 408 so a stock block works for me. I’ll look for an untouched stock early block. Might have a line on one.

 

[Timmy390]

Find a roller bock from an F150 or van. Lots of them in yards for cheap and they may only need honing to clean them up.

Tim

 

[rocknhorse76]

Thanks but I already have link bar lifters and a roller cam.

 

[Broncobowsher]

I would look for an '83 and newer block just for the 1-piece rear main seal. I look for EFI engines for the reason that the cylinder walls are typically in really great shape even with high miles, better fuel control over a carb drooling fuel down the intake.

These blocks are part of Ford's thin wall casting process. Not a lot of meat left on the bone. Some engines a .060 is no big deal, even .100 wouldn't be any concern. But this isn't one of those engines.

 

[Timmy390]

Thanks but I already have link bar lifters and a roller cam.

Take a step back to make a huge leap forward sell them both.

The cam that you get in the roller block post 94 will be the explorer cam and it does a really fine job in the Bronco. I've run it so I know. I reused the cam and lifters. The block was super clean and had very little wear in the boars. I did punch it 0.020 over just because. The E7 heads are arguably the third best factory head out there behind the gt40 and gt40p.

Van cost me $850. After parting it out and scrapping the rest I got the whole motor for $65.

Tim

 

[rocknhorse76]

Take a step back to make a huge leap forward sell them both.

The cam that you get in the roller block post 94 will be the explorer cam and it does a really fine job in the Bronco. I've run it so I know. I reused the cam and lifters. The block was super clean and had very little wear in the boars. I did punch it 0.020 over just because. The E7 heads are arguably the third best factory head out there behind the gt40 and gt40p.

Van cost me $850. After parting it out and scrapping the rest I got the whole motor for $65.

Tim

Apparently you guys assumed that I’m still running a carb and bone stock engine lol. Using those parts isn’t a step forward for me. I have a Lunati Voodoo hydraulic roller EFI cam, and ported D0OE heads with 1.94/1.60 valves. My EFI system is A9P-based with 36# injectors, 70mm BBK TB, ported and extrude-honed Lightning upper and lower plenums, 80mm slot style MAF housing, and 255lph fuel pump. Far from a stock engine with a fuel-drooling conventional or electronic carburetor.

When I converted to EFI several years ago, I had smaller injectors, Exploder intake/TB, and a crap eBay tune that ran super fat and very likely washed my cylinders down. Hence the oil consumption that just got worse as the years went by. Lesson learned. Since then, I progressed to a Moates QH, had Garry (EFI Guy) build me a good tune, and I burned a chip. Pretty sure the nail in the coffin for this engine was a relay that recently failed and didn’t allow spark. Injectors still worked and filled the cylinders with fuel since the EFI works on bank fire until the engine starts.

I was planning on freshening up the heads I have and using them for now, with plans to upgrade to AFR heads in a year or so. I’d prefer to use my block since it is an early (heavier) casting , but would consider using a later block for the 1-piece rear main. Also might be getting another early block for free.

Long story short, I’m looking for real-world experience with an early block that has been bored .060” over. Thanks.

 

[Timmy390]

Get it sonic checked and go for it. Lots of threads on this topic on Stang and Truck boards. Some say do it others say sleeve it. Really come down to the block. If the sonic says it's good then I would do it.

Had my 390FE sonic checked because it had to go .040 over. It runs good and don't overheat but it will need sleeves or junked if i build it again. Does run warm on hot summer days in stop and go but it's an air flow issue. Cools right down when rolling.

Tim

 

[Broncobowsher]

It's going to be hard to find anyone who has done the 0.060 over since very few people will even try it, being it is well known that small block fords don't like it and are well known for running host doing so.

Now add in you are after a performance build and not just grandma going to the grocery store, church, and bingo. A little thicker cylinder walls for some cylinder stability will be a good thing.

What I have seen from the 70's blocks has not been that good. The casting tolerances are pretty garbage. If you really think you can get away with it, I would start with sonic checking the walls to see what material is left, where the thick and more important the thin spots are at. As an old machinist once told me, you can't make the inside hole bigger than the outside material.

 

[JB Fab]

It's going to be hard to find anyone who has done the 0.060 over since very few people will even try it, being it is well known that small block fords don't like it and are well known for running host doing so.

Now add in you are after a performance build and not just grandma going to the grocery store, church, and bingo. A little thicker cylinder walls for some cylinder stability will be a good thing.

What I have seen from the 70's blocks has not been that good. The casting tolerances are pretty garbage. If you really think you can get away with it, I would start with sonic checking the walls to see what material is left, where the thick and more important the thin spots are at. As an old machinist once told me, you can't make the inside hole bigger than the outside material.

100% spot-on... I know two people right now that are kicking themselves for going .040 & .030 over on SBF performance builds. I would like to hear of how someone made .060 work (it's only the bad stuff that you hear).

 

[79INA69]

Apparently you guys assumed that I’m still running a carb and bone stock engine lol. Using those parts isn’t a step forward for me. I have a Lunati Voodoo hydraulic roller EFI cam, and ported D0OE heads with 1.94/1.60 valves. My EFI system is A9P-based with 36# injectors, 70mm BBK TB, ported and extrude-honed Lightning upper and lower plenums, 80mm slot style MAF housing, and 255lph fuel pump. Far from a stock engine with a fuel-drooling conventional or electronic carburetor.

When I converted to EFI several years ago, I had smaller injectors, Exploder intake/TB, and a crap eBay tune that ran super fat and very likely washed my cylinders down. Hence the oil consumption that just got worse as the years went by. Lesson learned. Since then, I progressed to a Moates QH, had Garry (EFI Guy) build me a good tune, and I burned a chip. Pretty sure the nail in the coffin for this engine was a relay that recently failed and didn’t allow spark. Injectors still worked and filled the cylinders with fuel since the EFI works on bank fire until the engine starts.

I was planning on freshening up the heads I have and using them for now, with plans to upgrade to AFR heads in a year or so. I’d prefer to use my block since it is an early (heavier) casting , but would consider using a later block for the 1-piece rear main. Also might be getting another early block for free.

Long story short, I’m looking for real-world experience with an early block that has been bored .060” over. Thanks.

I have a 69 351W block .040" over with a 4" stroker kit. One note on the early blocks is the deck height is 9.480" vs the later blocks 9.5". The kit I have in my 69 Mustang was from 06-07 year range, and when assembled I was .020" out of the hole...Not sure if this kit was ordered wrong or was too new to have a piston for the early deck. I had to disassemble all those spiral locks and have the pistons decked .020". Something to think about when choosing a block or kit.

 

[Broncobowsher]

I have a 69 351W block .040" over with a 4" stroker kit. One note on the early blocks is the deck height is 9.480" vs the later blocks 9.5". The kit I have in my 69 Mustang was from 06-07 year range, and when assembled I was .020" out of the hole...Not sure if this kit was ordered wrong or was too new to have a piston for the early deck. I had to disassemble all those spiral locks and have the pistons decked .020". Something to think about when choosing a block or kit.

I had the same issue with a '70 block. Wasn't a stroker kit, but it was a long rod conversion. At time I feel like the only one who has ever done a long rod / stock stroke 351. I left the piston poking up that .023". Turned into a really tight quench, but that thing ran great. 11:1 compression with a mild cam. In the winter I could run mid-grade fuel and in a pinch even a bit of regular. Summer still took premium. Had to do head gaskets a couple of times (known issue with the O-ringed Felpros on Trick flow heads). Nothing ever touched and the carbon traces all looked perfect on the heads and pistons. I really liked the detonation control of the tight quench height.

 

[broncozx]

I have one, and with a 427 kit, it should be 430 now. It has been used in some drifting. Still runs good

 

[bmc69]

Long story short, I’m looking for real-world experience with an early block that has been bored .060” over. Thanks.

I've bored many of those to .060 over. The key, as others mentioned, is the results of the sonic wall thickness tests. Core shift was always a problem "back then" and actually still is today..as a friend of mine who has spent a lot of time and treasure to develiop a new 351C block has found out.

 

[rocknhorse76]

My block is a ‘74 so it has the taller deck height. I was also given another ‘74 block that I’m having checked out at the machine shop. That one has never been rebuilt and has stock bore. I’m hoping it only has to go .030” over.

 

[Broncobowsher]

Sounds like a good plan. It's getting hard to find anything before the 90's that is still usable.

 

[bigmuddy]

I have a 74 block remanned, that was checked out locally and setup with a larger cam and GT40 heads, roller rockers. Its sitting on a stand to go in my bronco, hopefully its not an issue...

 

[DirtDonk]

Did the checkout include sonic checking cylinder wall thickness? If so I would think you're ok.
But are you saying you know it's been bored .060" over already?
Is it a 302 or a 351?

Paul

 

[BroncoJimbo]

I've got 75K miles on a .060 351W block. 1974 vintage IIRC. No problems. Runs cool.