428 Rotating Assy.?

[lovehamr]

Well, BDR 687's block ('66 428) and heads Edelbrock 427 w/2.19" intake and 1.71" ex) are at the only machine shop in this area that I trust. The next step is the rotating assy. The block will have to go .030 over and I don't want the machinist to have to clearance the block. That being said, the displacement is an open subject as is the makeup and vender for the assy. I'll be going with a hyd. roller cam and probably won't spin it over 5.5K so I don't think a forged steel crank and H beam rods are needed. I do have to admit that both of those score high on the CDI scale though (Chicks Dig It.) I do want some reliability and would like to read some members experiences that would be germane to my quest for snake power.

Thanks, Steve

[blykins]

FE's don't require block clearancing. My advice is go big on the cubes, match the hydraulic roller cam to the displacement, heads, and intake...and you'll have a very stout, streetable engine.

A forged crank is not necessary. The Scat 9000 cranks will handle more power than you'll ever need. There are many 600-700hp FE's running around with those crankshafts.

My advice is to go with a 4.25" Scat crankshaft and pair it up with a nice set of Scat 6.700" BBC rods. The rods will be inexpensive (Chebbie parts are cheap) and there are many piston choices for this combination.

This will net you about 462 cubes. Combined with a nice hydraulic roller, those Edelbrock heads and a nice Edelbrock Performer RPM or Blue Thunder intake, you'll be approaching 600hp with the torque to back it up.

[olddog]

Originally Posted by lovehamr

Well, BDR 687's block ('66 428) and heads Edelbrock 427 w/2.19" intake and 1.71" ex) are at the only machine shop in this area that I trust.

My memory (that I do not trust) is that the larger valves for the 427 will hit the cylinder wall on the smaller bore 428. It seems that the cylinder can be machined for the valve to clear, but it is argued that the shrouding of the valve makes it not worth the effort. I'm not sure if the 2.19" works OK with a 428 or not. Hopefully someone will let you know if I remember this correctly or if I'm full of crap.

[Woodz428]

Originally Posted by olddog

My memory (that I do not trust) is that the larger valves for the 427 will hit the cylinder wall on the smaller bore 428. It seems that the cylinder can be machined for the valve to clear, but it is argued that the shrouding of the valve makes it not worth the effort. I'm not sure if the 2.19" works OK with a 428 or not. Hopefully someone will let you know if I remember this correctly or if I'm full of crap.

I think you are correct. I am not sure regarding the Edelbrock heads, but stock 427 heads won't work without notching. I think a good argument could be made for the plus and minuses of doing that. The weakening of the cylinders for a flow advantage that is unlikely needed or to be used doesn't make sense on many levels. I'd use a set of the 2.09/1.66 heads( or their equivalent, those are factory CJ sizes)

[blykins]

I think on a 390 it would be tight, but a 428 bore should be fine.

[blykins]

Well, let me retract that. The intake valve should be roomy, but I think the larger exhaust valve (I thought you were running a 1.65") might be tight.

[Keithc8]

Scat or Eagle cast steel crank with a 4.250 stroke, Scat 6.700 I-beam rods, Diamond dish piston for 10 to 1 compression, Mahle rings, Clevite or Federal Mogul bearings all for 1499.00. We buy in volume and past the savings on to our cutomers. This will give you about 460C.I. and is by far the best bang for the buck that you can do. Thanks, Keith Craft

[lovehamr]

I did tell the machinist to check for valve shrouding and that notching may be necessary. I got the heads ported with the new valve train off of ebay un-run for $1500 and couldn't pass them up. The way I see it is I could've spent a lot more money and gotten a lot less head (is that a funny?) but if I ever go with a 427 bore block then I'm set as well.

My understanding (this is my first FE) is that with some stroker cranks and H beam rods that there could be interference with the cylinder skirts and/or cam. Am I missing something? Also, using the 4.250 stroke and resultant 462 ci, even with the larger 76cc head that I’m running I’d have to use a dished piston as I calculate my CR to be about 12.21 (assuming zero deck and a .038” gasket.) That sounds high to me. I already have one car that I have to mix race gas with and I’d like to drive the Cobra more.

From what I’ve found cruising this forum and others is that there are a few places to get the parts from in a matched kit form from; the most notables of which being our own Barry R and Keith C. Any one here use someone different with good results?

Another question (I know, will he ever shut up?) has anyone used the new type Holman Moody intake? It looks like a Blue thunder but with the HM on it. But I wouldn’t swear to that.

Steve

[lovehamr]

Keith, thanks for the post. You posted while I was trying to figure out what to write! What would you suggest for a flywheel and damper with that combo? Also, are those Diamond pistons forged?

Thanks, Steve

[Anthony]

Originally Posted by olddog

My memory (that I do not trust) is that the larger valves for the 427 will hit the cylinder wall on the smaller bore 428. It seems that the cylinder can be machined for the valve to clear, but it is argued that the shrouding of the valve makes it not worth the effort. I'm not sure if the 2.19" works OK with a 428 or not. Hopefully someone will let you know if I remember this correctly or if I'm full of crap.

Genuine ford 427 heads have a wider spacing of the valves than 390-428 heads, both the intake valve and exhaust valve from bore centerline. I think you can run 427 heads with 2.19 valves with 4.13 bores, but you can't run the 427 TP heads with 2.25 intake.

The edelbrock heads from what I remember, have the intake valve spaced from bore centerline like a 428 head, and the exhaust valve spaced like a 427 head, for both of their FE offerings, the 428 and the 427 head, mainly different in the combustion chamber size and exhaust bolt pattern, but again, no difference in valve spacing, so running an edelbrock 427 head on a 4.13 (4.160) bore block should be OK.

The other significant factor concerning this is proper rocker arm spacing on the shaft to get the rocker tip on the center of the valve stem, as again, the edelbrock head is neither an exact 428 or 427 head, but a mixture of both.

[blykins]

There is no interference with FE stroker parts. Now if it was a SBF, then you would have to do some clearancing.

There are dished pistons available, you do not have to run race gas. Probe has a dished piston for your application that would put you at exactly 10:1 with the pistons at zero deck.

[Barry_R]

The Edelbrock heads on a 428 will clear with a 2.200 intake valve and be OK with a 1.71 exhaust. It's cozy in there, but not a real problem. A 390 based engine will have issues with the exhaust valve before the intake - but I've done those with a bore notch.

If you choose the stroker kit - whether the 3.98 stroke, the 4.125, or the 4.250, I prefer to internal balance them. Means that the flywheel and damper are common 390/427 parts and are easy to find and service.

Dampers are kinda funny - the cheapest (but still seem OK) Professional Products Chinese ones are well thought out with FE pulley bolt spacing, an included single groove pulley, a universal FE timing pointer, and clear instructions. The definitely far superior quality ATI piece has Chevy pulley bolt spacing, cryptic instructions, no timing pointer, and is about 7 degrees off from a stock FE (You be making/modifying a pointer).

Flywheels are a match to your clutch manufacturer item for me. Although the bolt patterns are supposed to be a standard per clutch type, I still find problems from time to time when I mix them up...

[Chaplin]

Originally Posted by Barry_R

The Edelbrock heads on a 428 will clear with a 2.200 intake valve and be OK with a 1.71 exhaust. It's cozy in there, but not a real problem. A 390 based engine will have issues with the exhaust valve before the intake - but I've done those with a bore notch.

If you choose the stroker kit - whether the 3.98 stroke, the 4.125, or the 4.250, I prefer to internal balance them. Means that the flywheel and damper are common 390/427 parts and are easy to find and service.

Dampers are kinda funny - the cheapest (but still seem OK) Professional Products Chinese ones are well thought out with FE pulley bolt spacing, an included single groove pulley, a universal FE timing pointer, and clear instructions. The definitely far superior quality ATI piece has Chevy pulley bolt spacing, cryptic instructions, no timing pointer, and is about 7 degrees off from a stock FE (You be making/modifying a pointer).

Flywheels are a match to your clutch manufacturer item for me. Although the bolt patterns are supposed to be a standard per clutch type, I still find problems from time to time when I mix them up...

427 valves in Edelbrock heads with a standard 428 bore will hit the cylinder walls, trust me, I've seen it happen with a relatively mild cam- (.560 lift). If you take the bore to 30 over you might be o.k., but with a std bore, it will hit.

[blykins]

They will fit....tight, but they will fit.

[Chaplin]

They won't fit, they'll just hit a little bit, but they'll hit. Trust me, I'll post a pic later.

[McD00]

I just don't like FE.
IF bigger were better than wouldn't the Indy & Formula One cars have
Big Block motors ??? You see there is a rule of diminishing return that goes like this, the bigger the bore
the larger the rod and the larger the rod the slower it goes round and round but if we increase the bore we can force the rod
around until it breaks. It's called Forced Extraction later shortened to FE !!! It's one of the reasons that the 289 Cobras have
all of the race history and the 427 Cobras are know as rod breakers..........

McVette

[blykins]

If Indy and Formula 1 cars were racing on the street from 1500-5500 rpm, then they'd have big blocks.

Funny, I've never heard 427's being known as "rod breakers"

Your top fuel alcohol dragsters are not running small blocks, I can assure you.


BTW, bigger bores do not require longer rods.....longer strokes do.

Misinformation yields lots of confusion.

[patrickt]

Originally Posted by blykins

If Indy and Formula 1 cars were racing on the street from 1500-5500 rpm, then they'd have big blocks.

If memory serves, Indy is capped at 3.0L and F1 at 2.4L. Brent, moronic misinformation like that is best just ignored.

[blykins]

Yep, that's why they have to zing them up to 13000 rpm. I bet they have all of 5 lb-ft of torque below 10k.

I can't ignore a statement like that.

[patrickt]

Originally Posted by blykins

Yep, that's why they have to zing them up to 13000 rpm. I bet they have all of 5 lb-ft of torque below 10k.

I can't ignore a statement like that.

And every one of them has a solid, flat tappet cam with a 114 LSA.