427 Stroker kits, Which?

[BenBaron]

Hi guys,

decided to go with a 427 stroker for my 351w (74 block), just cant resist!!!. Ive found 2 kit suppliers CHP and stage 3 motorsports (I believe its probe stuff they supply).

Im looking for any other suppliers and really ease of installation and purchase as Im over in the UK it needs to be correct on the first order.

First of all which supplier would you lot go for?

Secondly Im planning on using a retro fit hydraulic roller cam (the one with the spider in the valley) and Ive seen some mention of kits that say they need a small base circle cam, now call me stupid but Im not too sure what that is and if its compatible with a retro fit cam?

any help/comment greatfully received..

ben

[Streetwize]

I had one of the first CHP 427 kits, in fact you can say I did some early R&D for them, they hadn't got all the bugs out at the time. But as a fairly experienced engine builder, I was able to give them some decent input (especially with regard to the possible need for the smaller base circle cam) that they incorporated int otheir later kits.

A small base circle cam means the lobes are cut off of a smaller base diameter core, this allows for the clearence required for the long 4.17" stroke crank's connecting rod shoulders to have adequate running clearance around the cam lobes. The first kits used shoulder bolt connecting rods that would actually extend into the cam tunnel; they can be close but IMO you need at least .060" clearence at the closest points with the cam degreed in. I ran a gear drive for added insurance. It's fine but I told them the early kits would have been disasterous if built by a novice builder who might not have thought to check. I suggested they go to H beam rods with cap screws which is what they used in later kits.

My 427 (really 'only' 426, just like the "real" 427fe actually was) is a real screamer, IMO don't buy all the bunk about short rods, side loading, it's very overblown. If a motor goes slow and won't rev high with short rods it's usually because you don't have enough head, induction or cam for the motor! Don't take my word for it, ask Jon Kaase, the 30+ IHRA mountain motor pro stock engine builder (815" w/1.35:1 rod ratio) as well as the PHR Enginemasters Challenge winner who won with a 470" short rod FE. True short rods motors don't make good sustained high RPM endurance type motors but for street cars (that run at part throttle 85-90% of the time) and occasional week-end acceleration (drag and road race) motors they are tough to beat with the right heads and cam.

As far as builders, you may be money ahead to buy a very reasonably priced short block from an experienced veteran Ford builder like Keith Craft. If you build it yourself, I reccommend using only the best, most reputable Experienced Ford machinist in your area, get your block, square decked, line honed and bored with deck plates and the bellhousing (and preferably a blowproof scattershield in a Cobra...remember your right calf is alongside with the clutch!!) torqued in place.

I'd run a head with intake flows of at least 250 @.400 lift and ~280 @.500 lift, at 10:1 and a ~236-240 @.050 cam with ~.540 lift. Along with a Ported Victor Jr and an 800cfm carb and min 1 7/8" primaries you can make right at or slightly over 500hp/500lb-ft and have an extremely broad powerband with perfect street manners, Jeckyl and Hyde, a torquey *****cat for cruising and a tire shredding monster when you put your foot into it. Guys put bigger cams in these cars but really wind up making lower average torque and power, the simple reason is that with typical Cobra style sidepipes the primary tubes wind up around ~36" long, that's really too long to allow a bigger cam motor to really raise the peak torque RPM high enough to really wring out the extra big end HP a bigger cam would provide, so instead the big cam costs more upper bottom and mid range torque (especially part and roll on throttle) than is gained in top end power. Unless you want to run a shorter 28-30" primary and a 3 1/2' by ~10-12" collector before the muffler, there's really no good effective way to make the cobra sidepipe system produce the kind of hp a bigger cam motor might make on a dyno with drag race style headers, might as well make the most out of the torque curve you have.

Just my .02 cents.


www.streetwizeperformance.com

[LMH]

You might contact AD Performance and see what they can put together. I talked to them a while ago when I was thinking of doing the same thing you are. They told me at the time they can put together a kit like your looking for. www.adperformance.com
Larry

[BenBaron]

Wow, cheers guys for loads of info, Im a bit closer now, much appriciate it..

Ben

[RACER X #99]

Ben,
Most knowledgable small block builders seem the think that the sb 427 does not have a good rod ratio. Most of the big cube"racing" small blocks are around 408-410 cubes. You can build an engine of this size and still tell everybody it's a 427 if that number is important to you.As far as performance, any of the big cube small blocks will usually beat up on the FE's.
If you are building just for show and cruising why not build an FE.

RD

[BenBaron]

Hi RD,

I would have loved to build an FE but I over in the uk and cost for parts and the block itsself is an issue. I already have a 351w block and toploader (for SB for to now go with an FE Id be looking at replacing the lot..too many pennies for me that one, missues would skin me.

I see where your comming from with the dodgy rod ratio but there seem to be lots of people running the kits and lots of opinion both ways. The way I see it at the moment is that Im not gunna be running it to death and if I put say a 408 in then I would always feel like I should have just gone with the bigger stroker. Anyway Its just too late, Ive made up my mind.

Thanx for the opinions all

[Streetwize]

http://popularhotrodding.com/enginem...racing_engine/

Here's a good read for many of those who think or led to believe that short rod motors don't work well...they cite things like "excessive side loading" and friction losses...well that's true...they will be higher proportional to RPM, but under 6500 or so not enough to worry about and with the right (reead: BIGGER) heads and valve timing, for moderate rpm motors (below 6800 or so) desiring a wide (not peaky) powerband, they make for formidable engines not to be taken lightly.

Excessive Side loading and friction....I would only take 'Excessive' to mean beyond the physical lubrication and thermal properties of the oil....haven't seen that yet in any of my stroker motors.

Jon Kaase has 2 of the last 3 Enginemasters contests, motors that produce the highest average torque and horsepower across a 2500-6500 RPM powerband on 93 octane pump gas.

He won at 470" cube limit with an FE ford, the 410 limit with a Windsor and the 510" limit with a Pontiac....the one common denominator of all three winning motors???? Big strokes with Short rod ratios, killer heads and camshafts. He could have built them with bigger bores, longer rods and shorter strokes and got to those cubes any number of ways...yet he chose the "less popular" way.

For those of you not familiar with Jon Kasse, he has been the premiere IHRA Mountain Motor Pro Stock engine builder (815 cubes, 1700+ hp normally aspirated) for about 30 years now.

opinions vary....but I've been in the Kaase camp for over 10 years now..I've heard all the "expert arguments" but I just keep building them big stroke, big heads and whatever rod will still keep the pin within the ring pack.

[ERA Chas]

Not to pick nits but Jon did not win last year with the Pontiac-Lennert Bergquist did with BBC.

[Streetwize]

Originally Posted by ERA Chas

Not to pick nits but Jon did not win last year with the Pontiac-Lennert Bergquist did with BBC.

Chas,

No doubt, but Kaase is well respected in Ford Circles...just pointing out that short rod motors can and do make some serious power

[LMH]

When I was thinking of building a production block 427W, I talked to a number of owners of them. I couldn't find one person who had a failure with the engine. I'm sure it happens but I couldn't find one.
All told me they would build one again and thought it was a great engine.
Larry

[Tony Radford]

I've got 15K miles on a 427W built in a production block. My car is very street friendly and has 400 ft/lbs to the back wheels. I replaced a stock stroke Windsor with this one and I've been smiling ever since. Southern Automotive built it with a Scat forged rotating assembly, KB pistons, Erson roller rockers and an Elgin mechanical flat tappet cam. I drive the PP out of it and it does great. I think it's a great way to go.

[ERA Chas]

Wize,

I'm a huge fan of Jon's work and he's a classy gentleman and well liked by the other competitors. They all gather to watch his pulls. I agree fully your point on short rods. Ben may not be able to heed your advice.

[ScatStroker]

Ben,

Stage 3 is a reseller of Probe/CHP. Your components would be dropshipped from CHP/Probe if that's the route that you decided to go. To the best of my knowledge there is only one source for a 4.17" crank and companies then private label the crankshaft to whatever they want (CHP, DSS, ect - all resellers, none of which manufacture crankshafts.) We're also a dealer for Probe/CHP, as are a number of other sources. If you're interested we can blueprint the crank before its shipped to you - a step most others aren't willing to take (because it's being dropshipped or they're not capable of the service.)


Wize,

John's use of a short connecting rod really didn't have anything to do with the reasons you cite - It had to do with detonation and limited octane fuel. John's motor was running over 13:1 on 92 octane spec gasoline, a short rod pulls the piston away at TDC faster than a long rod and is less prone to detonation. As an EMC competitor we're pretty familiar with the builds. His Big Block was also a 460 based entry, not an FE. But the arguement is correct, IMO, the examples are just a bit flawed.


Think about it this was as well... (devils advocate)

IF the "poor" rod ratio caused the engine to prematurely wear out - What would it get 50%? Figuring a "long lasting" performance engine at 100k, the "poor rod" ratio combination would get 50k miles. We have customers that have ran motors past that with the "infamous" pin intersecting 347's and other combo's with lower rod ratios than the 427 kits. Most of these cars are driven 2-3k/year - If the engine lasted 20 years would you be dissapointed?


If it's the magic 427 number you're looking for then build the kit, it'll be fine.

$.02

Brian
www.ADperformance.com

PS: Thank you LMH.

[Streetwize]

Brian

Point taken on the 460, I could have sworn it was an FE. Thanks.


Yes the fast pull away from TDC is less detonation prone but as a result it also draws a little harder on "too big ports and cams", allowing him to make the big power up high and still have decent torque down low in the 2500-4000 range. In other words the pumping eficiency given up by the shorter stroke at higher piston speeds is offset by the surplus of valve timing and headflow.

I'm primarily a mopar guy but I've built strokers of all makes, I'm building a 517" version of my buddy Steve Dulcich's third place 470 from the '03 contest, using a 4.30 stroke and 6.535 rods with the same Chapman 380 cfm heads that Steve ran. The only other difference is, I'm running a roller (268/274 @.050, ~700./680 lift). I'm going for the same 2500-6500 EM style powerband.

[ScatStroker]

Wize,

The contest is a good example of possibilities but people need to understand that they are PURPOSE built engines... replicating them can achieve similar results but there is a lot of details in the motors that aren't covered and make a big difference in the overall build. The compression and camshafts are also unrealistic, they're just nowhere close to streetable.

You'll see different rod lengths and bore sizes this year, our motors have a compression restriction. I personally generally prefer a longer rod but the proof will be in the pudding when it's all sorted out...

Mopars are a little different, we do quite a few strokers for them but they're far from my expertise.

The bottom line on a build like the 427 is that it doesn't matter. A 6" rod or a 6.250" really isn't going to make a noticable difference, you can go either way. Go with the rod that clears the counterweight and has a shelf piston to match, that's the correct rod length in this equation.

Brian

[BenBaron]

Brian, Ive pmed you


Thanx for the info to the rest of you guys, very helpful


cheers
Ben

[pmfranke]

i did a 74 351 stroker with a roller cam retro fit and it did take a fair amount of work that i was not aware of , ie. grinding a flat place for the dog bones to rest .If they are not flat they will wear and get caught on the lifter.also it takes a special size push rod. drill and tap the bolts for the spider and do the grinding before you boil out the block to avoid chips of metal in the wrong places .so far mine sounds and runs great ,less than 1000 miles. Good luck.

[BenBaron]

Pmfranke, I presume your talking 427 stroker? If so then can I ask what cam you went for as Im in the process of sourcing that and dont want any problems with the cam to rod clearance..

Cheers guys

Ben