Pros & cons of a 527" FE

[thorconstr]

I'm thinking of building a 527" aluminum FI 427 SO. Pros and cons?

[RICK LAKE]

thorcontr What's the problem?It will not look right unless you add a set of 58mm TWM 's on the top. KCR has built a few, He would be the one to ask. I know there is a close cam to rod or crank thrown that needs to be check. Who's block, crank and rods are you going with?? IMO the only thing I am carefull with on any stroker is real good oil pressure, like 60-75 psi at 2,500 rpm and limit the RPM's to 6,200 with max at 6,500rpm. That's alot of mass you are spinning. Barry R. sells a nice stroker kit for what you want. They will balance it for another couple hundred dollars. I installed a 482 kit in my Shelby block and everything worked out fine on clearances. You just have to stretch the rod bolts with a gauge and cut the ring for the pistons. What cam are you looking at. KCR sells some great custom hydro rollers. I have a small one in my 482 and will do the same in my 498 bigger motor with your TWM 58mm on it. I wouldn't over build the motor. There are other guys on the forum that will tell you that bigger and badder is not better in the long run. 10.5 compression and a good set of ported and polished heads will give you more power than you may want. My 482 torque motor is a handful. Your 527 is even more. Tell us about gears for the rearend,trans, and power you are looking for? This will help fill in the blanks. 600 HP and torque is a safe limit for any cobra, after this, if not very careful is like playing with a loaded gun. Hope to hear more on this build. What block are you going with? Rick Lake

[ERA Chas]

It will easily make upwards of 650-750lb-ft (depending on how aggressive you build and the maximum stroke) and be all done by 6000. Unless you make the car drag-specific it's an expensive academic exercise.
Also with no upper powerband, the EFI is wasted.

[thorconstr]

I will probably use a Shelby block with a billet crank, was the crank you spoke of billet Rick? I'm going to put it in a RCR MarkIV GT40 with a Ricardo 6 speed transaxel and 58MM TWM on top, for sure. T&D rockers and some really good roller hydraulics. I'll get together with Keith about the internals and head work. That's about as big as you can go with an FE. It is a big johnson contest after all! I want to get the same feeling I had the first time I jumped on my Kirkham. Sheer terror! And then look for some new ways to get more horsepower!

[wtm442]

Pros - tire shredding torque, permanent grin

Cons - bills shredding bank account.

If you got the $$, go for it!

[silverstreak]

Sounds like a great motor spec to me! I'm pretty sure K Kraft did a great 527 for his own Kirkham a couple years ago. I remember him writing he was real satisfied with the results. I think he went 4.5 inch throw on his Shelby block.
I built my 511'' at 4.25 stroke and 4.375 bore with a big bore Shelby block and just picked a cast Scat comp lightwieght stoker crank because I set my ems to govern at 6250 rpm. All the power's made by then, no need to overwork anything. I spent my extra pennies on great rods.
Initially, opening the 58 throttles with commitment was intimidating. Like anything else you get used to it and realize you actually could use and effectively control much more power at the all important 40 to 140 mph range!
Good luck with your next powerplant.

[Ronbo]

I have to admit the big bore block is a temptation but the cylinder sleeves are awfull thin between the bores and seems like head gasket blow-out could be a big problem. I remember the problems guys had running high compression on 400 SBC's even with reinforced gaskets.

If you want large cubes why not go with a Boss 429 setup? This engine doesn't have all the "bugs" the old FE had. There's a company that makes a full aluminum setup, just google Boss "429 blocks" and you'lll see them.

[Jac Mac]

If nothing else it will help decide if the Ricardo torque limits are fact or fiction assuming you have the tyres to load it up.

[thorconstr]

I didn't realize it at the time, but the journey (the build) was as much fun as arriving at the finish line. I'm really looking forward to this one!

[thorconstr]

Silverstreak, That engine really pulls in all gears, doesn't it? In my 496 with TWM 4th gear is awesome. I was getting into it on a 4 lane connector in CT. 4th gear at 100mph is 4600 rpm, peak torque, 680 ft lbs. I have 335/35/17s Pilot Sports on the rear, 13" of tire. At 100mph it felt a little greasy, it was breaking the tires loose! That was a scary/good feeling. Nothing beats big inches!

[Keithc8]

Pros: You build what you want, You have something that everybody does not have, You get all sorts of power at all rpms, heads breath better with the 4.375 bore, torque is better down low with the 4.375 stroke, you do not have to use full throttle very often, not a whole lot more than other stroker FE engines.
Cons: why did I not do this sooner
I have built several of these and have had zero problems with them. The blocks are dry between the cylinders anyway and the 4.375 block gets bigger sleeves so you have the same sleeve material as a 4.250 bore block. We have the Scat billet and KCR 4340 forging in stock, use a 6.700 rod and we have a Diamond piston for the application as well. Do stage three heads with the larger hydraulic roller, lighter valvetrain, T&D rockers and make a easy 700HP with the stack injection and maybe more. I did my with a solid street roller with about 200 seat pressure and 500 open pressure and it made power to 7000 rpms which was 750HP on premium pump gas.
Just let me know how I can help when you are ready and we will build you one bad FE for the new car. we have built one or two of them. Thanks, Keith