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Anybody have experiance with either 408 or 377ci stroker motors based on a cleveland block.Im looking for both pros and cons.Im leaning towards the 408 kit from Speed-O- Motive.Ill be using closed chamber 4bbl heads,a 4 bolt block and i think i want to run around 9.5 compression.A mild cam around 550 lift,230-235 @ .50 duration with a 110 lobe center so i have decent vacumn for my brakes.Im guesing about 425 hp,450lbs tq?
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A few years back I purchased a '71 Pantera with no oil pressure. To make a long story short, the engine had a broken push rod and two bent rods. Rather than a stright rebuild, I build the engine using a Coast High Performance stroker kit, reworked heads, a split duration cam, Victor highrise intake and a 750 double pumper. The thing riped!! Gobs of low end and it would windup to about 6500 rpm. A business turnaround forced me to sell the car but if I ever need to rebuild the engine in my current Pantera I would not think twice about taking the same route.

[This message has been edited by b4_thndr (edited 06-12-2003).]

[This message has been edited by b4_thndr (edited 06-12-2003).]
I went with the 377 inch kit. In general I have found that the big stroke changes create several problems such as the one you mentioned. In addition the sever rod angle that most of them create leads to reduced engine life. At my age, I'll live with a few less "ponies" for the sake of street ability and longevity. On the street, a properly built 377 will give you more than enough power to attract unwanted attention from the law.
I put together a 391 stroker using SCAT's 3.850" crank and 6.125" rods. This keeps the stroke/rod ratio good but does put the pin in the oil ring. I can't say anything about longevity yet (I only have 450 miles on the engine so far) and I know I'll probably have to replace the rings every 30k miles or so but it'll take me several years to put 30k on the engine and it's got HUGE amounts of power.
Severely rearranging the innards of an engine with a stroker crank can be done various ways. First, the crank counterweights must be cut down to miss the sides of the crankcases and the oil pump castings. This is counter to what the engine needs to balence the engine, so most shops cut the crank & grind the cases the absolute minimum, then use slugs of Mallory-metal (a tungsten alloy) to get things balenced again, at more expense. The drilled holes for the heavy metal slugs must be drilled parallel to the crank, not the "easy way" down into the counterweights, as centrifugal force WILL sling verticle slugs, even if welded in, out through the pan (or block) like missles at higher rpms. The wristpin rises up into the ring stack unless you have custom pistons built. If you choose to use some sort of "stock" piston for economics, the oil control ring can be supported by two aluminum plugs in the wristpin hole, with a section of ring groove machined in each, or a steel support ring under the oil control ring. Both work for short periods; it depends on whose pistons you use as to how they do it. Both are drag-race mods which implies very frequent rebuilds. Note the plugs do not take the place of pin locks like Spirolox or E-rings, as 99% of strokers use floating wristpins for more convenient rebuilds. Finally, unless you use ultra-premium parts and clearance the bearings for it, the redline on a stroker motor will be lower than what you had stock, so a rev-limiter is a good idea Some cheaper commercial stroker cranks are cast-steel made in Taiwan, rather than much stronger forged steel units. The ads often only say 'steel'.... There are other problems with some combinations, involving the rods and the cam lobes interfering with each other, too. I suggest you contact an engine builder who has actually put one or two of these things together successfully, rather than trying to accumulate a bunch of parts yourself, and learning expensively what doesn't work. This is really Advanced Engine Building 101, not just a quick overhaul.
Originally posted by jack deryke:
I suggest you contact an engine builder who has actually put one or two of these things together successfully, rather than trying to accumulate a bunch of parts yourself, and learning expensively what doesn't work. This is really Advanced Engine Building 101, not just a quick overhaul.

My 351 Cleveland was stroked to 383 by Kuntz & Craft (I believe maybe Kuntz & Company now?? Website below). It is real fast (no, it does not do 200 that I know of) and reliable at 7,000 mi so far. I am real happy with the build and would suggest checking with them. It also has Ported and Polished SVO A-3 Aluminum Heads, 10.5 to 1 Compression, Crane Roller Rockers, 3.75" Stroker Crank, Solid Lifter Competition Cam, Crower 3/8" Push Rods, Stainless Steel Valves, Jack Rousch Aluminum Intake Manifold, MSD Ignition, 6300 Rev Limiter, Holly 870 cfm Carb, Child & Alberts 6' Rods and Venolia Pistons.
I concur with Jack. If you want to do it yourself buy a kit from a reputable and experienced Ford high performance vendor. If you want a turnkey engine, stay with shop that specializes in Ford high performance builds and take their recommendations. A friend of mine had a local performance shop (I won�t name them) build him a 347 for is resto-mod �65 Mustang. After spending 5+ grand with a predominately Chevy shop, the engine has never been right. He has taken the engine back several times, each time the �fix� has introduced additional problems. The last time, we got a dyno sheet that was for a date that they did not have the engine.
The CHP 377 I used was balance, had a steel crank and required minimal bloc clearance work. As I recall there were only two places and the material removed was less than a quarter inch.
Good Luck
Have you considered the Stroker Motor PI sells ?

What is everyone feelings about the motor they have put together for 10 grand ?

Originally posted by Mark:
I just got off the phone with Kuntz & Company. These guys are great. I would strongly suggest giving them a call. I hope to be putting my order in soon for my stroker kit with them.

[This message has been edited by Cozman (edited 07-03-2003).]
yup, I'll build my own.
Maybe I'll hit $6,000.00 but it will be Detroit Iron and the best parts I can find, split the cost with my favorite machine shop & I provide labor and parts, all 351C. Hot Rodders have alway's curtailed costs by doing there own work.
I've notice folks upset with the cost of a shop doing the work and this is probably a case in point.
Also when you repair and modify your Pantera's on your own they seem to have a bit more worth!
Just my 2 cents.
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