More stroke, more displacement. Where to begin?

[Hearsesrock427]

I've had this idea bouncing around. Screw aftermarket cylinder heads and aftermarket camshafts. Why deal with a can of worms if you don't have to? Why not just raise displacement, throw on some higher rate injectors, and get a tune to optimize these gains. You skirt all the mixing and matching issues (ie: getting your cam, heads, and valvetrain working together), and gain as much, if not more power!

Ergo, I'd like to learn more about bumping up the displacement of my lopo from 4.9 to 5.8 liters. I want more stroke, lots more stroke. More power + more usable power is always a good thing. Especially for these big boats.

Questions:
-How much would it cost?
-Specific supporting mods? (ie: which rate fuel injectors should I buy?)
-Any places you reccomend I go to, both for the machining work and for the mandatory EEC-IV tune? (I know of a local speed shop that might be able to do both parts of the job, but I'll have to see.)

[turbo2256b]

You mean from a 302 to a 351W or stroking a 302

[pantera77]

I'm assuming he means 302 -> 347 but if I'm reading this right he want's to do all this work and put the stock e6's and lopo cam back in. Congrats, you'll have a $3k+ bottom end that runs 16s.
More engine = more air. A lopo is already choked to shit, increasing displacement doesn't magically make it get more air.

[turbo2256b]

I might stroke a 302 to 331 but would rather go with a 351W than a 341 stroker.

[Hearsesrock427]

Thanks for the tips and insights so far.

@Turbo2256b: Stroking a 302. So why not stroke the 302 to 5.8 liters and beyond? I'm guessing it's the issue of the lopo's inherent choking (restrictive heads, restrictive cam, etc.) that pantera mentioned?

@pantera77: You read it right. I actually forgot about the restrictive stock heads. Ported E7s or ported GT-40s come to mind. You mentioned people dump E7s for cheap on SBFtech and Corral a lot. Perhaps I could score some unported E7s there, and get them ported. Might even be able to find some GT-40s.

Will also either get the stock intake ported, or rock a ported Exploder intake. I almost forgot about this part of the equation; thank you for jogging my memory!

I keep coming back to the Exploder cam, but even that might choke the motor. (It's a stock cam; it can only be so good.). Still a slight improvement over stock, just probably not a big one.

I really don't want to get into aftermarket cams and heads if I can avoid it. Because with those, you have valvetrain, pushrod, and lifter compatibility issues to sort out. All of which cost time and money. I want to progress through Ebyt's build faster than I did last summer. I'll be more than happy to cross that bridge to aftermarket a couple years down the road, and go all-out on it.

[turbo2256b]

Beyond 347 you would need an aftermarket block for a 302. RPMs are a bit limited to a 347 due to limitations. A bit pricy too for the ricipricating mass.
My book better and possibly cheaper to go with a 351. 347 or 351W is a lot better off with some aluminum heads in the 165 to 175 cc port size. So money spent on a stroker kit could be used for better heads. Intake set up would be pricy for either as the stoker intake off a 302 would be too restrictive for a stroker 302 and the 351W would most likely have to be aftermarket also Using EFI.
A 331 might do well with a set of ported GT40s even then best off with aftermarket intake for EFI
Any of these builds would require tuning the factory ECM. Dosent take all that much to go beyond the factory ECM programing.

[Bobcat]

I'd start off with a 351, maybe bore it .30 over to 351? Use flat top Pistons and some decent rods. Don't waste your money on stroking a motor and planning to use factory heads, as all of the engine gurus have said above me. Get some sort of aluminum heads, any aluminum head from any company is better than any stock Lopo head. Then choose a good intake, In order for it to get air and you'd want a good cam. Just an HO can is a waste.

Then there's those 302 guys who will die by their stroked 302s when the 351 already has the stroke and displacement. Just has shitty rods and Pistons. DO NOT USE E7s. IIRC thumper E7s are the best ones you can get. If you're goingn to use iron heads. Use GT40s or GT40Ps.

[turbo2256b]

Thumper E7s are crap they dont flow as much as DOOE, GT40S OR Ps as cast.
These heads were realy designed for a smaller engine than 351.
I used to think Thumper heads were not to bad but flow tested a set and they didnt flow but about 30 CFM total over stock E7s. My E7 ported heads flow like 160 CFM over stock 220 ish CFM @.500 lift compaired to 140CFM stock. Old 289 heads flowed 160 CFM as cast.
E7 heads as cast are one of the worst flowing factory heads.

By total CFM i MEAN ADDING .1,.2, .3 and so on flow numbers togeather.

[gadget73]

If you're really looking to make a serious engine, the first thing that needs to go is any Ford cylinder head casting. None of them breathe effectively enough to support a motor making serious power. You can make a bunch more power with stock displacement and good heads than you will with big displacement and crap heads. Engines are nothing more than an air pump. The more efficiently air can move through it, the more power it makes.


Agreed with starting on a 351 if you really want displacement. One does weigh a bit more than a 347, but a stock 351 block will cost a lot less than making a 347, and it will not have the horsepower limitations a 302 block does. The Mustang guys with 347's are prone to blowing head gaskets and stuff. The block actually will twist under the heads at high rpm, causing the gaskets to squirt out. Wind them too much and it will twist enough to split from the crank journals right up through the lifter galley. The 351 is a much stronger block and will take a hell of a lot more abuse before it splits like that. To be fair, you're probably in the 450-500 hp range before a 302 cracks up but a 351 will do somewhere closer to 800hp before it gives out. It is a physically bigger engine, but look how big your engine bay is. There is plenty enough room for a 351 in there.

[Hearsesrock427]

Alright, looks like Ebyt's build is going to become a can of worms whether I like it or not. Doesn't make any sense to stroke the holy hell out of the lopo and then run the restrictive stock parts or off-the-shelf parts. I'm not going to half-ass a build. Not now, not ever. So effective today, we're going all in. Thank you all, for taking the plunge with me.

Beyond 347 you would need an aftermarket block for a 302. RPMs are a bit limited to a 347 due to limitations. A bit pricy too for the ricipricating mass.
My book better and possibly cheaper to go with a 351. 347 or 351W is a lot better off with some aluminum heads in the 165 to 175 cc port size. So money spent on a stroker kit could be used for better heads. Intake set up would be pricy for either as the stoker intake off a 302 would be too restrictive for a stroker 302 and the 351W would most likely have to be aftermarket also Using EFI.
A 331 might do well with a set of ported GT40s even then best off with aftermarket intake for EFI
Any of these builds would require tuning the factory ECM. Dosent take all that much to go beyond the factory ECM programing.

Ah, gotcha. I don't mind sticking to lower RPMs. In fact, I prefer the proverbial low RPM torque monster. Reliability > singing sound of high RPMs. 331 stroker it is. Little less expensive than the 347, and not so close to the proverbial cieling, while still being a welcome improvement over stock.

I actually considered the 351 very early on. Before I even bought Ebyt. My biggest issue with just dropping in a 351 and building it is the SEFI fitment. I looked and looked for a 100%, hard-and-fast guide to EFI 351s in the box panther. There are combinations that should work, as per expert testimony. But I have yet to see a 351 Windsor with SEFI. If it was so easy, why don't people do it, like people do the carb to SEFI or CFI to SEFI swaps? I can definitely see the merits though, make no mistake.

Aftermarket aluminum heads make sense, for a lot of good reasons. As we know, anything beats the stock E6 heads. But more than that, they're lighter. Best place to save weight is down low in the front of the vehicle. THOSE are the gains I'm looking for. You can simultaneously go faster and get lighter. I got a small taste of it with my long tube headers, and now I want more. Thanks for the port size specs too- I'll start browsing Trick Flow and AFR later tonight after I reply to everybody.

Intake is also going to be aftermarket. I kinda figured that with the stroking and the aftermarket heads that ported stock/off the shelf parts simply wouldn't cut it. Any good brands of intakes to buy? I'm thinking of TrickFlow, AFR, and BBK, but I'm sure there are others.

Oh yeah; I knew that coming in. Read up a good amount on Speed Density EFI before I bought Ebyt. SD EFI tends to be easily disturbed. Even just swapping in a cam can make it run like crap. No way it will work with the stroking, aftermarket heads, etc.

I'd start off with a 351, maybe bore it .30 over to 351? Use flat top Pistons and some decent rods. Don't waste your money on stroking a motor and planning to use factory heads, as all of the engine gurus have said above me. Get some sort of aluminum heads, any aluminum head from any company is better than any stock Lopo head. Then choose a good intake, In order for it to get air and you'd want a good cam. Just an HO can is a waste.

Then there's those 302 guys who will die by their stroked 302s when the 351 already has the stroke and displacement. Just has shitty rods and Pistons. DO NOT USE E7s. IIRC thumper E7s are the best ones you can get. If you're goingn to use iron heads. Use GT40s or GT40Ps.

My only issue with the 351 is the lack of SEFI support, as I noted earlier. I agree with everything else you said. No plans on using E7s, or any iron heads either..... I'm going aluminum now. Lighter AND more power? That's a no-brainer.

If you're really looking to make a serious engine, the first thing that needs to go is any Ford cylinder head casting. None of them breathe effectively enough to support a motor making serious power. You can make a bunch more power with stock displacement and good heads than you will with big displacement and crap heads. Engines are nothing more than an air pump. The more efficiently air can move through it, the more power it makes.


Agreed with starting on a 351 if you really want displacement. One does weigh a bit more than a 347, but a stock 351 block will cost a lot less than making a 347, and it will not have the horsepower limitations a 302 block does. The Mustang guys with 347's are prone to blowing head gaskets and stuff. The block actually will twist under the heads at high rpm, causing the gaskets to squirt out. Wind them too much and it will twist enough to split from the crank journals right up through the lifter galley. The 351 is a much stronger block and will take a hell of a lot more abuse before it splits like that. To be fair, you're probably in the 450-500 hp range before a 302 cracks up but a 351 will do somewhere closer to 800hp before it gives out. It is a physically bigger engine, but look how big your engine bay is. There is plenty enough room for a 351 in there.

Amen to that. I'll get to looking for aluminum heads as soon as I'm done replying here. I'm going with a 331 stroker, with good heads. Why settle for one or the other when you can have both? Embracing excess FTW.

I would, but I just see it as a hassle to get SEFI working on a 351, as I've mentioned to others here. And no worries, I'm "only" rocking a 331. It's like the goldilocks between the stock displacement and the big honker 347. Blowing head gaskets is next to impossible on these cars, or so I've heard. Am I really gonna gain THAT much power from this stuff, to the point where I risk blowing head gaskets and cracking the block? I've only got 150 HP/270 TQ at the crank to start with!

[gadget73]

Its not that difficult, you just need the right lower intake. It exists, and they aren't even super spendy. The issue is many are tall, and between the extra deck height of the motor and a tall intake you might need a hood scoop for clearance. As for the wiring and such, you use stock wiring, probably a stock fuel rail modified for more width, and a Mustang mass air ECM tuned as needed. Honestly its not a lot more trouble than doing it with a 302 based engine. Widening the fuel rail is just a matter of extending the pieces of flexible line between the hard pipe parts.

[LithiumCobalt]

Unless I'm missing something, why are you having such a difficult time finding support for fuel injected 351s? They could be had in F-150s up through 1996. I don't think they were all that rare.

[pantera77]

Unless I'm missing something, why are you having such a difficult time finding support for fuel injected 351s? They could be had in F-150s up through 1996. I don't think they were all that rare.

I don't think the truck intakes fit.

But a 351 with a lighting lower and Explorer upper should be fine if not damn close.
But ya, a SEFI 351 isn't hard at all....

[Bobcat]

Ironically enough, the kid I was going to buy my trans from, had a 351 SEFI motor in his fox. He had the whole edlebrock top end kit, heads, upper and lower intake and I believe he was running a letter cam.
He's currently trying to sell his entire SEFI setup so that he can get a carb (yes it astounds me too) and he was looking to get 300$ for both. Which I thought was a steal.

Honestly. The money you'll spend on a stroker kit, you can cut in half with a 351 rebuild. I just put a 351 in my coupe and it fits with NO issues. They came with em. I plan to goto SEFI in the future, after I have my carb experience and learn all about them. It seems foolish to me, to stroke a 302, when you can just get more stroke and cubes with a motor equally the size and will cost less..
All you'd need to find, is a 351 lower. The deck height isn't much more than a 302, it's only that the heads are farther apart. I don't see how you'd have any clearance problems, if you take that money from a stroker kit and buy a lower, used even. Not like they 'go bad'.

Sorry for rambling, trying to save yah some money and get you the best outcome.

[Hearsesrock427]

Figured I'd post the parts list before I start looking through the replies.

Cam: http://www.compcams.com/Company/CC/c...csid=1602&sb=2
Heads: http://www.trickflow.com/partdetail....1&autoview=sku OR http://www.airflowresearch.com/index.php?cPath=21_106
Intake: http://www.americanmuscle.com/edelbr...ldii-8695.html
Stroking Kit: http://www.americanmuscle.com/scatst...cast-7995.html

How are we so far?