Connecting Rods

[Rick Parker]

Calles Compstar or Scat H Beams. Both with 7/16 ARP 2000 Cap Screws. Anyone with experience with either of these. Going with 5.400 length .927 bushed floating pin and standard 2.123 Journal on Boss 302 Crank. Mixed reports on use of Girdle on 2 bolt Mexican 302 Block?

[blykins]

I've used almost every rod imaginable. You don't need either one of those for your application. Remember, an h-beam isn't always stronger and most are heavier. Any rod you choose is going to last much longer than your block....

Just stay away from cheap stuff...no eagle, procomp, etc.

I'd use a good scat I beam and not think twice. Of course, I've told you that every time you've asked this question in the past year... ;-)

I'd also use a .912" or smaller pin and a light custom piston and think super hard about cutting the rod journals down to a 2.100 or a 2.000 journal.

[ERA Chas]

^^^
Fits well with your big RPM plan Rick...

[Rick Parker]

Well I'm committed to a .927 pin. I got Mahle flat tops with pin height of 1.300. They were the only "Shelf Piston" that I could find with 1.300. They were actually for a 351/408 application. I guess not too many use a 5.400 rod with a 3.0 stroke, generally people jump to stroker applications, but right now thats not anything I'm wanting to do. I hope I don't regret it. I'm trying to avoid the word "Custom" but still do real nice build. They are a short skirt type with a short pin. I've got a real real nice .010/.010 Boss 302 steel crank. I guess I could sell it and buy an aftermarket one with 2.000 or 2.100 journals. Back in the day the Ford camp used a 5.315 rod length instead of the 5.155 that was the production 289/Boss 302 length.

[blykins]

Can you return the pistons?

Cup engines run a 1.880 journal with a .866" wrist pin or smaller.

If you don't want to cut on your boss crank, I'd get a scat crank, turn it down and go that way.

[ERA Chas]

Brent, why does Rick's standard journal size impede high 7k RPM? Didn't the Trans Am 302 Bosses run those numbers in the day? I get it about the pin and piston weight.
Those Cup sizes are crazy but yield almost 10K RPM...

[blykins]

Doesn't really impede it, but it's something that can add to performance and longevity. We have gained tons of info since the original cars ran in the 70's. A smaller journal cuts down bearing speed which is a big factor in running high rpms continually.

[blykins]

With a 2.123" rod journal, you don't have as many choices in a 5.400" rod. That's why it would be beneficial to use another crank or cut the journals down so that you can access the SBC 2.100" rods.

However, if you stay with the factory journal diameter, the Scats will work just fine.

[RICK LAKE]

Rick Parker Rick need an answer to this question. The rest will answer itself. As far as a girdle for the bottom end, I recommend it even with the small machine work that MAY need to be done, extra support is just that.
What is the budget we are looking at? If cost is not an issue, BME aluminum rods. Saves weight, any size rod bearing you want, same applies for the piston pin size. Gun drill the rod for extra oiling to the pin and forgetaboutit. Price about $1,500.00. Only thing you need to do is warn the motor before hard driving. Titanium is next to the tune of about $4,000.00. Custom price.
Now looking at a couple of other companies, Cat, Scat and Eagle, If you have a good machinist, get the rods and have them redone and shotpeened. I like the "I" rod over the "H" rod. Limit the prms to 6500. The motor should like a long and happy life. ARP the bottom end. A good balance job of the rotating assembly will add life to the motor also. Need the WHOLE thing done completely, this includes the pulley to the flywheel. All parts need to be part a line with marks when done. I ran eagle rods in my FE for 7 years and had no failures. I did use ARP 2000 rod bolts and follow the torque method of assembly. IMO 2 things that are very important to any motor, getting oil to the correct temp for max efficiently and plenty of oil pressure with 60-75 psi at 2,500 rpms. Adding a pre oiler like an accusump also stops dry cranking conditions. The oil pressure you raed at the gauge IS NOT what the farthest rod bearing is getting. Save this for another thread. Good luck Rick Ps couldn't find any info for Ford rods in Howard or Callies, guessing custom made. Don't get scaried of aluminum, they need added clearance and weight is about 70-100 grams lighter, must allow material to warn up. Load factor is about 1/2 the limit at 7,000 rpms for this rod and piston. I friend running aluminums in an SBC with 28,000 miles on them and no problems. been in motor for 11 years of abuse. Just a thought. I do agree with going to a SBC rod size or even a 1.88" honda rod. Less weight faster rotational speed from idle. Clearance is most important. My FE is running BBC rods and no problems, race only. Rick.

[Jerry Clayton]

You can't just grind the crank to the Chev or Honda sizes because the Ford throw is quite a bit narrower than they are---however, an aftermarket crank can be made to those either of those sizes----------

[blykins]

Yeah, sorry, I was in FE mode.....I have FE cranks ground to a BBC journal all the time.

[Jerry Clayton]

or do you mean aftermarket cranks to BBC sizes??????? Ford used very narrow bearings compared to every one else and a bigger diameter---------you don't want to widen the throw on a stock casting

[blykins]

Not aftermarket cranks... Factory cranks widened and turned down to a BBC rod journal. We do it all the time...with 361/391 cranks, and other factory cranks. Pretty common place.

Just had Adney Brown cut a 391 crank for me and we used a BBC rod journal dimension. It's currently in a 427 road race engine in the UK.

[Rick Parker]

Brent are you suggesting the Scat Pro Stock I beam Ford rod. I want to be able to spin 7000-7500, I question if these are capable of that? Pro Comp model not listed in 8.2 deck sizing

[PLDRIVE]

Post removed, my apologies to Brent

[blykins]

I know Jim Kuntz. I have a lot of respect for Jim, or any other builder that's been doing it for decades. However Mark, I think that comment should have been made privately. Of course, tact and common sense are not traits that are widespread on public forums these days...

Rick, how much horsepower are you planning on making? 400? 425? Those rods with the 3/8" ARP cap screws are stronger than anything the factory ever had. I will tell you this... I have a customer running one of my 347 SBF's in a 7.50 1/8th mile car. I'm using those very same rods, and he's launching at 5500 and shifting at 7000. This is a car that will tickle the 6's in the 1/8th mile. Not sure what the horsepower is, it dyno'd at 486, but that was with a smaller carb. We picked up some ET with a new Quick Fuel 750.

The crank and rods will probably out-live the block.

If you're really concerned about it, go with a Crower Sportsman rod, or something similar, and try to keep it light. As far as Scat H-beams and Compstar H-beams, they're going to be exactly the same. Heavier, but equal quality.

I would skip the girdle altogether, put some ARP studs in the mains, and make sure the rotating assembly is light and balanced very well. A girdle will do nothing but hold the caps together when the block splits in two. I've seen pictures of a 302 block literally broken in half, and all the girdle did was keep the main caps bolted together so it was easier to clean up.

[PANAVIA]

or how about ;

Titanium Crower Connecting Rod W/Cap Screw Ford 289-302 Custom Length (5.000" To 6.400" C To C) - 289-302 - Titanium - Ford - Domestic - Connecting Rods

[Barry_R]

You can move into a Callies Ultra series rod if you want an intermediate step. They are U.S. sourced Timken steel, forged in Trenton, MI, and machined in Fostoria, Ohio.

They have a very nice H beam that goes for just under a grand, and an exquisite lightweight I beam that is around $1500ish - far prettier than a Oliver or Crower piece.

Of course the basic Scat I beam will likely be just fine - but you've already heard that option, so I am letting you know about a really high quality domestic made alternative.

[Rick Parker]

I elected to go with Calles Compstar. They appeared to be finished a little better than than Scat or Eagle. As much as I wanted "Premium Rods" I acknowledge that it is unnecessary unless I want to upgrade the block too. So I'll use the $$ in other parts of the engine. Thank you all for your input .

[blykins]

They're a nice rod. They are not from Callies' USA line of parts, but they are equivilent to a Scat H-beam.