FE Power Forums
FE Power Forums => FE Technical Forum => Topic started by: blykins on January 26, 2020, 08:32:05 AM
-
I’m putting some feelers out for some potential product interest and feedback.
I’m thinking of having some rods made that would help out the guys who run 352’s, 390’s, 427’s, and 428’s by allowing them to use a shorter, lighter piston.
At first glance I would be looking at something like a 6.625-6.630 length so that the 352/360 guys could run a shelf 390 piston or even a custom 390 piston.
For the 390/427 guys, this would mean a 1.630” piston, and the 428 guys would get a 1.530” piston.
I would also be interested in looking at a 6.700-6.800 length rod with an FE journal. I’ve done some 390’s and 427’s with BBC journal cranks and 6.800 rods, which makes for a nice combo.
I would be targeting a $400-$500 price for a set, 4340, I-beam, rated for 700 hp with a 8740 bolt.
Feedback?
-
I just bought another 428 engine for a future build.
I would be interested in a 428 set.
Greg
-
Would be nice to have that choice
Any thoughts on size of small end and weight ??
Ricky.
-
Interested, Yes but if i ever get to the point using a set i dont know
-
The 6.7 would have been cool to have before my 482 was put together, then I wouldn't have botched the upper and lower positions of the rod bearings. Otherwise, I'm not sure of the applications.
-
I like the idea although not something I'll ever need. Price point seems more than reasonable and I'd think it could be a nice route to go for many.
-
Yes for me I have a standard bore 352 I would love to build.
-
At that price I think it would be a good idea. Shoot plenty of 360's still out there with the only answer "make it a 390". Some times its harder to find the 390 crank and rods than you think (for some people). Plus the cost of recon.
What would the weight comparison be, would a balance be needed for low budget/rpm stuff?
-
I have approached Scat and Molnar so far. Scat said minimum custom order is 100 sets. So that means I'm out with Scat....LOL
Molnar has replied but the pricing would be quite a bit higher than $500. However, they are primo rods and would be lighter than about anything out there. Still exploring options, but judging by the responses, the interest just may not be there.
-
If the option had been there when i asembled my 390
i had bought them
-
I have approached Scat and Molnar so far. Scat said minimum custom order is 100 sets. So that means I'm out with Scat....LOL
Molnar has replied but the pricing would be quite a bit higher than $500. However, they are primo rods and would be lighter than about anything out there. Still exploring options, but judging by the responses, the interest just may not be there.
I know Blair had Molnar make some up similar to what your talking about but for a custom piston in mind. He is putting one together for me now w/360 crank. He can fill in the specifics if he wishes.
But I think It's a win, win with one part, that doesn't happen very often. Something a hobbyist or small local machine shop can order up ready to go and and utilize the good parts they already have without adding extra cost all the way to pro engine builders.
Just a guess but with Molnar reputation for light(er) rods I would wager the weight in the added length it would still keep the balance as close as anything produced as when it was new. If this where to actually be the case the price difference between Scat and Molnar would be offset by the cost to re balance.
I think most on this forum are more max performance orientated, and the benefits aren't as prevalent when you already have a 445 stroker. So the positive feedback may not be much from that type of crowd. (Absolutely nothing negative should be derived from that statement.) Just more Mustangs w/428's and Galaxies w/427's than guys with 360 trucks.
Shoot, a stock 360 with a quench of 0.135 and 7.6:1 compression ratio to 0.041 quench and 9:1 compression ratio is a big jump for say $600 bucks. (assuming 10cc piston and 72cc head) It would be a cheap way to make a runner out of a 360. Without adding reciprocating weight while adding a margin of safety. Plus all the other combinations it could be used in!
Got my vote Brent, but my opinion doesn't carry much weight compared to smarter more experienced guys this forum.
-
I've got clearance from Molnar for 6.630", 6.700", and 6.800". I think Blair had some 352 rod length rods made up, 6.540" or so if I remember right. The 6.630" rods would let a 352 guy run any shelf 390 piston, lose some reciprocating end weight, and go that route....or would let a 427 or 428 guy end up with a shorter, lighter piston. The 6.7/6.8 stuff would be an option for any stock rod journal FE and would let the 352 guys end up with a reasonable short piston for a custom application.
This is one of those things where there are some guys out there doing it, but maybe just not enough to justify a batch order. The Molnar stuff is super nice though: super light, and come with nice fasteners.
I'd be willing to do the first 10 sets for $699 just to get them out there and test the waters. If I can get 10 takers (I'm one of them), we can proceed.
-
Would Molnar be able to do a 6.7/6.8 rod with BBC journal diameter, but FE width? If so, I’d be in for a set.
-
They're willing to do anything, as long as I have enough orders to make it worthwhile.
The only thing about the FE width and BBC diameter is narrowing the bearings.
-
The only thing about the FE width and BBC diameter is narrowing the bearings.
The crank in my cammer is a Ford $ steel shaft that has been offset ground to 4.00” stroke with a 2.200” rod journal. I’m currently running a BBC 6.385” rod that has been narrowed, along with the bearing. I’d prefer a longer rod with lighter pistons, no problems having the bearings narrowed again.
-
Just throwin' this out there;
It might be more attractive if this was offered as a piston/rod kit, and maybe a balanced crank/piston/rod kit. I understand that can create inventory and backorder issues. I have no idea if the kit concept outsells individual parts.
Many builds go hokey when you are building from individual parts. Valvetrain stuff seems to be the worst potential for mismatched parts.
If you are not an experienced builder...and sometime even when you are, using a kit removes some of the potential for mistakes. Yes, even if you can do math, you can still have issues.
I don't know, maybe I'm all messed up on this.
-
Just throwin' this out there;
It might be more attractive if this was offered as a piston/rod kit, and maybe a balanced crank/piston/rod kit. I understand that can create inventory and backorder issues. I have no idea if the kit concept outsells individual parts.
Many builds go hokey when you are building from individual parts. Valvetrain stuff seems to be the worst potential for mismatched parts.
If you are not an experienced builder...and sometime even when you are, using a kit removes some of the potential for mistakes. Yes, even if you can do math, you can still have issues.
I don't know, maybe I'm all messed up on this.
Gerry, I've never really been a fan of kits, unless the pistons were ordered on a custom-order basis. I sell a lot of custom pistons just because there are guys who don't want to bore .030, .040, .060, etc., or have different needs with the block's deck height, volume, etc. In all honesty, I don't keep shelf pistons, just because there's too big of a chance that they will sit for awhile.
I do agree on the valvetrain stuff. Ordering a cam and springs out of a catalog is a recipe for disaster as the catalog doesn't know how far your valves have been sunk, how heavy your valves are, etc. Even when guys call and order springs to match a camshaft, I have them measure their install height and give me all the info.
-
That makes sense. I suppose you would be willing to work with a customer to "build" a kit from the individual components, right?
-
That makes sense. I suppose you would be willing to work with a customer to "build" a kit from the individual components, right?
That's normally how I do it. The crank and rods are the easy parts normally. The pistons take a little figurin' and I try to get the customer to have the deck height laid out, heads cc'd, camshaft chosen, etc.
-
There is a lot that can be done, along these lines.
The stock FE rod bearing size (TRW CB 760) is .734 wide X 2.438 ID. The old dowel pinned 427 bearing is .746 X 2.438 (TRW CB 830).
For reference, the BBC (TRW CB 743) is .892 wide X 2.199 dia.
The old 390 Cadillac engine, also used 7/8" wide rods and there rod bearing width is .760, with a 2.250 dia journal. BTW, the Cad rod is 6.5 long, interesting, huh? Almost a direct replacement for a 390 Ford, with reground crank pins. Offset you get 3.96 stroke.
Guess how wide the 351C rod bearing is? It is only .008 narrower than the 390 bearing, at .726 wide and could be used in this application. With it, you could offset grind a 390 crank to 3.900 and a 428 crank, to 4.100 stroke.
But, since we started taking about using the BBC rod journal size, another option is the 292/312, 7/8" wide rod, it's bearing is .746 wide X 2.188 dia (TRW CB 461), only .011 smaller than the BBC. If you offset grind for that bearing, you can have 4.03 stoked 390 cranks and 4.23 stroke, 428 cranks.
Something that hasn't be brought up, is why do we need the .975 wrist pins? We are taking about SBF/SBC size pistons that do extremely well with 4 - 4 3/16 diameter pistons. You get additional piston weight reduction, with thesmaller pin, too. There are many, off the shelf pistons available for the .927 WP. They include, 1.54-1.56, 1.42, 1.30, 1.25-1.28, 1.165, 1.125-1.13, 1.09-1.10 and 1.06-1.025. Mix and match!
More crank pin options, include the following, TRW bearing #'s:
CB 676, .726 X 2.123, 289/302
CB 698, .755 X 2.001
CB 610, .742 X 2.000
-
Hey frnkeore :-)
Lots of cool info, I looked into all kinds of combos
What threw me off was $500.00 or more to offset grind a 390 or 428 crank by anyone I could find that could do it
Then custom pistons an such ..... was exploring something with a Ford 400 rod as well
Ricky.
-
Give Mario a call. I talked to him, about 2 months ago and he gave me a price of about $250 for a flathead crank but, said that that price goes for most cranks.
He is a old racer (Sprint Car, I think) and knows what he talks about.
Contact Information:
L & M Grinding
1301 E Cypress Ave
Redding, CA 96002
Contact: Mario Frugugliette
Title: Owner
Phone: (530) 221-7652
-
I was doing some cross referencing (TRW/Speedpro/Clevite) in the Clevite catalog and stumble on this rod bearing.
I think it's a good diameter for the FE and you can still get a .12R on the crank pin with it.
-
That is a good idea. It has always perplexed me how the engineers could go through the steps to produce a piston and miss the equations needed to come up with the correct piston height. At least within .030" of a common machined deck.