alrighty, I got my 351w roller back from the machine shop. I have decided that I want to do a 393 stroker motor. Won't be 393, more like 389 since I didn't have the block bored .030 over since it didn't need it. (very low mileage)
Alrighty I have been looking at cranks on ebay from diffirent distributors. I cannot decide on weather I want forged or cast. I WANT forged, but I am only using it on a bronco, with mild lift. either way I cannot decide If I want it machined to have ford rod journals, so I can use the stock rods, or have it machined to use sbc journals, so I can use cheap 6.2 chevy rods. The chevy rods are longer, so I would think I would get more performace right?

Does anyone know how to notch cylinders? I need to know how to do this!!!
I have picures of the finished product, but I need to know where to do the grinding. Also, after I grind it, will I need to chamfer the cylinder around the notch?

Also it says to use 302 pistions with the kit. Well what 302 pistons? There are tons of em. I assume I want em dished to keep compresion low. I am looking into aftermarked heads with 2.02 intake and 1.6 exhaust valves, so It hasta clear em.

Long tube headers, ceramic coated. Must me street legal, so I guess there is a cat in my future.


I am also curious about a roller cam. I would like one that will take advantage of the crank. Any recommendations?

Thanks

 

My advise is to keep it simple (the KISS principle), since this is your first stroker build. The simplest is to buy a complete kit from Scat, Coast High Performance, or one of the many companies offering stroker kits for the Windsor now. If the block wasn't bored, exactly what was done- honed? decked? align honed mains? etc.

1> No reason to buy a forged crank unless you're building a race engine, and winding it to the moon- money better spent elsewhere.
2> If you spend the money to grind the crank for "cheaper" SBC rods, where did you save any money? The "longer rod, more performance" thing is a whole 'nother discussion. Then there's the expense of balancing the assembly that comes balanced in most kits ($$$).
3> There are templates available for cylinder notching, and are even included in some kits. I have notched blocks without a template before, but it's time consuming and was done before any machine work was done to the block. Yes to chamfering the bores.
4>Piston choices can get very complicated- you have to know a lot of specifics about the rest of your engine to determine what's right for you- desired compression ratio (fuel to be run, forced induction or naturally aspirated, etc.) piston-to-deck clearance, combustion chamber size and design, valve layout, camshaft lift and valve events (which also determines dynamic c.r.), rod length,and more.
5>Again, camshaft specs are subjective and determined by the entire engine and vehicle. Go to any cam website and find their cam recommendation card, that you can send them, and you will see what I mean. The time and money spent putting together a bunch of pieces that may not work together would be better spent purchsing a kit with all the guesswork taken out already. Call a reputable company that deals with strokers (I highly recommend Coast High Performance-check out their website) and you'll be glad you did. It's what they do, and they're great to work with.


Pete

 

the cost for the crank is the same, regardless of which journals I get, that is why I ask.
I am interested in the rod legnth discussion. I've read that longer rods=longer dwell time=more performance. Is there a problem with this?

 

From what my mentors in engine building taught me, the longer rods were used as a crutch to over come the crappy heads they had to deal with at the time. They could use the dwell time at tdc and bdc to help cheat the charging time of the cylinders.
A longer rod does not dwell the same amount of time at both points nor does a "short rod"
The longer will spend less time around BDC, more at TDC
The opposite is also true.

A longer rod/stroke ratio puts more load on the mains and block webbing ... a shorter rod/stroke puts more load on the cylinder walls.

A longer rod/stroke ratio is more forgiving to a small or "not the best flowing" intake port ... a shorter rod/stroke ratio makes a large or better flowing intake port less lazy.

However, there is only MIMIMUM differences in most cases.

A link, and a quote:

Rod Ratio Effects - Page 1

Quote:"The total distance that the piston moves down the bore is solely determined by the stroke of the crank. But both the speed, and the acceleration of the piston are dictated by the rod ratio. The piston speed and acceleration can have numerous effects on the performance of an engine. The velocity of the piston (it's speed) can be important in determining how the intake charge is pulled through the ports and past the valves. A fast moving piston will pull harder on the ports, creating a larger Delta-P to "suck" air into the cylinder on the intake stroke. Here one might think of correlating the point of maximum piston speed to the point of maximum valve lift for example." Unquote.

My opinion? Unless you're building a race engine?-
The rod attaches the crank to the piston & the wheels on the bus go round & round....

A number of folks who know what they are doing building engines have said they don't subscribe to any magic r/s ratio. If you aren't designing an engine from scratch, including the block, and you have a given deck height and stroke, the design and mass of the piston are probably more important than rod length. Get the ring pack where you need it and a reasonable compression height, and the rod length will be what's left.

I'm enjoying this, but gotta get on the "honey-do" list. Be back later this evening-


Pete







My opinion, short version-
The rod attaches the crank to the piston & the wheels on the bus go round & round,,,,

 

I Have Just Completed A 393 Stroker, As For The Bottom End,i Used The 302 Coated Speed Pro Pistons(.030 Over) With The Stock Rods(make Sure They Are In Good Shape) And Got A Cast Eagle Crank 3.85 Stroke.this Combo Will Handle Up To About 500 Hp. If You Are Not Building A Race Motor This Will Get You Plenty Of Power And Will Not Hit You That Hard In The Wallet,and Use That Extra Cash To Get A Good Set Of Heads And Cam ,you Will Not Be Dissappionted When You're Finished

 

I was looking at the same eagle crank I think. Just my rods aren't in good shape, that is why I am wondering if It would help to get some sbc rods with the crank, since price is the same. I need a set of 351w rods or 6.2 sbc rods either way. I think the chevy ones would be cheaper. I am glad your combo did well. What cam did you get?

 

where can I get a template for notching the cylinders?

 

I Have The Comp Cams Xe274hr, 1.6 Roller Rockers & Roller Lifters,afr 185 Heads,edelbrock Rpm Air Gap Intake, 750 Aed Carb, Proform Dist. & I Refuse To Put Chevy Parts In My "ford"

 

A lot of questions, and I'll try and hit a few of them that haven't been adressed, as well as my 2 cents on a couple that have. I've gathered up most of the parts for my 399 stroker, but haven't put it together yet. I don't know about the chevy journal thing, (do the stock 302 pistons have the same pin size?) I chose the 393 type set-up for the stock rod and piston reason, even though I bought both new, and upgraded. Bought 302 Speed-pro hypereutic flat-tops(full float pins) for about $100. Stole my rods off ebay for $80.00, but you can buy them new for $150. all day long, ( I-beam forged, bushed for free floating pins, weight matched, and have ARP bolts.) They can't hardly give away stock reconditioned rods, so you could pick up a set for less than $60. Which pistons to use depends on which heads and what compression ratio you want to run. Since you are going with standard bore, CR shouldn't be that big an issue , even with flat-tops and small CC heads so I'd say go with them.As far as cams go, they won't really list any for strokers, so it's my contention to shop for the 351w that suits you, and then buy the next one up. Long rods give a teeny bit more low end torque, (more leverage), but this is not even noticeable, and not a reason to consider in the equation for a mild motor. To notch your block, use a Dremel or a die grinder, (it's not rocket science), and although I've seen templets advertised for 408 strokers, I haven't for 393's. The best way to clearance the block, (and everything else,you may need to grind a little off your oil pump as well), is to assemble the engine and carefully turn it over and see where you need to clearance everything. While you need bearings in place, I don't see the need for piston rings, or torquing anything down, at least untill you finish grinding and then do a final check when everything is ready. A good rule of thumb is .030 clearance everywhere. I'd ease the edge ot the notch with some fine emery, just for good measure.

 

HI, I built a 5.8 w/trick flow heads and ordered a piston notching tool to clear the valves.Basicly it replaces the intake valve then you use drill to cut the piston when it`s at tdc. It`s a slow process. I since stroked it to a 393 by calling Summit racing and ordered an Eagle cast crank kit that comes with forged trick flow pistons made by Probe that are made for the TF heads @10 to 1 comp