Just trying to learn these BBo. I know BBc and y OLDS buddy just says "take all you know about BBc and throw it out!".

So on an aggressive street 455, what is comsidered safe RPMlimit and what would be HIGH RPMs?

Now my BBc 498 shifts @9800 with a ingle 4500, and 10,400 or so with 2 x 4500 on the tunnelram.

Now thinking the 455 should RPM 6500 to 7000?

What do you guys think? I know what supporting RPMs can require as far as induction, cam and timing etc. Just wondering about bottom end mechanicals.

Thanks John

 

All the basics apply:
Light rotating assembly
Good machine work
Good balancing
There are a few girdles out there that tie the mains to the pan rails.
I think the rpms are more limited by head flow more than anything.
I have mine limited at 6300 presently, just for longevity mainly. That's with an offset ground 425 crank, BME rods, short CP Bullets, a medium cam, and 1st gen Edelbrock heads that have bigger valves,and port work. It might be out of breath, but won't know for sure without strapping it to rollers.

 

The 455 can spin to 6k easy. I slapped together a totally clapper 455 with ported J heads and with no testing and only one time out we managed an 11.64 lol. Trans was dying and we are almost positive we spun the #3 and ,4 rod bearings on the second pass when the rev limiter wasnt set. Pretty sure it saw 7k rpm. That engine has stock rods , stock crank , studs and main straps. Although it was a hunk of questions. The rod ends where actually still within size when I measured them and it saw nitrous before I dug into it in a previous life.

Now my 350 olds stock rods , stock crank , light pistons and it spins to 7k

The big block can spin but I think this is where most guys would opt for the 425 crank since it's forged and has a much better stroke imo for racing purposes . People have done all kinds of stuff and many have had success and many have had failure.

 

John, next time you do an oil change , stick an I phone cam up the drain hole to see if it actually does have aftermarket rods in it.

 

Ok will do, I think buddy has the small camera. Just better to know what the fall disassembly might run into. Really just like to ring and bearing the bottom end, maybe straps and ARP hardware if it's not there. Hoping to just do a top end and cam change.

Was originally hoping to break the 600Hp mark, but being more realistc as I learn the OLDS engines. 500 to 550 is more realistic now. And IF it does infact have aftermarket forged crank and rods, might just look at a nitrous set up for track days.

But I am impressed with the ETs some of your stuff did to!

 

My Danny Lattimore 507 makes 648 hp and turns 6300 rpm. It can be done. A racing friend spun his 455 to 6800 for 8 years before the thrust bearing gave up.

 

I’m not a professional engine builder, or machinist. But from what I have been told (and my own experience) a 455 will live a long live at 5500-5800. The more RPM, the life typically goes down. Use lighter pistons and rods, the safe limit goes up. I don’t think you will find a olds engine builder who thinks very highly of stock rods. That’s not to say they are junk, they just have limits.

 

Stock rods were never mentioned. Mine are 7.1 molnar rods.

 

Yep this info seems to going against what we have found to be the normal with various Fords and Chevys. We are getting away from light weight rotating assemblies for a stronger moe durable properly weighted assemblies. Heck even NHRA 500 ProStock has goone away from Aluminum rods for steel.

Now saying a better designed piston that is lighter is good and better then an old heavy TRW/SPEEDPRO. But usually lightweight cranks and rods actually have cost us ET and longevity.

 

X 2
Thats a pretty accurate statement.

As far as I know, aluminum rods have never had the longevity of a steel rod. Without a doubt, aftermarket steel connecting rods are lighter than stock, stronger than stock and have more longevity. .

 

You're going to have to come to grips with the lack of choice with an Olds vs Chevy. When someone says "lightweight", they are speaking relative to the offerings for an Olds. Not the near infinite possibilities with a Chevy. Scat rods and Mahle pistons for my 425 build were roughly 20% lighter than the stock stuff while adding considerably more strength.

 

Sounds like you're already consulting Dale and you have it all figured out. What was the point, again?

 

I haven't discussed anything with anyone other then whats posted here really. Just doing research and going from there. That way when engine comes out and apart, I will know what direction I want to go.

But yes Dale is fairily close to me. I have researched some of his biulds.

 

John

I good running production based 455 Olds will shift out of first @ 5300-5600 RPM them 5800 out of second to third, and go through about 6000 RPM in high gear, this gets you a high 10 sec pass with 4.10 gears and a 30X9 tire. The only time you would run a 455 Olds above 6000 RPM is to get it over the finish line, your surely not going to see peak power made over 6000 RPM.

 

How quick/MPH does your car run?

 

We are heading to Rock Falls Wisconsin this Friday to find out. Just got it in the car last weekend.

 

Very interested to know! Danny is a strong builder.

 

Yes he is! This is supposed to be the last engine he built before retiring. He's done 7 engines for me.

 

At what RPM was peak HP made?

 

Danny has been very reluctant to give me all the specs of this engine. It's .730 lift solid cam ported E heads 12.5:1 compression

 

Good luck.

 

What is the bore and stroke that was used to come up with 507 CID?

 

Umm, intriguing to say the least? I was thinking to make peak Hp about 56/5700, hold it a bit and shift @6000 with 28" tall tire. Also debating with something like YOUR thread about the BBc with stock converter and 2.56 gear?

This car I bought WILL see plenty of 3 hr highway trips. So bushing solid roller are probably going to make it into the program. Already bought the Torker intake, intake and header gaskets and Sniper that will support 650+Hp. Also not sure, but since this 455 of mine was supposedly built with nitrous in mind, and as a "stock" deal has run 11.90 with a 100hit, would like to keep that door open.

THIS IS ALL RESEARCH AND LERNING TILL ABOUT OCTOBER WHEN ENGINE COMES OUT FOR FRESHENING! If I don't break it before hand.....

 

I'll have to ask Danny how he did it. He's been reluctant to give up specs on this engine.

 

Would you mind sharing some details on your friends build as well as some of the other performance engines Dany Lattimore built for you?
Looking forward to see what your 507 runs out of the box good luck.

 

Well got 4 passes in at Cedar Creek Iowa. Nitto555R2 can not hook with the new engine. Put the slicks on and ran a 1.5 60 foot time but car was heading right into the other lane backed out but the 60 foot was on the back tires. Traction and some improvements in the chassis will be required. It's a whole new learning experience with the 507. Improvements coming.

 

Any MPH?

 

I thought you were going to Rock Falls WI ? Where is Cedar Creek IA ?

 

I had that problem of heading to other lane added air bag on the passenger side and it went away.

 

Nittos are junk; learning that lesson the hard way, too.

 

That improvement is already on the list.

 

I wholeheartedly agree. Got no traction what so ever.

 

I know that I am not drag racer. Totally out of my class. I am looking at Continental ExtremeContact Sport 285/40R17 100 W Tire for the rear of my car. Anyone have experience?

 

Strange??? I personally seen a few friends with 555 run low 10. From what we have found, there not ET Streets/slick, but better then most any other street tire. On a real streetcar they last a lot longer then ET Streets. Hook better then Cooper Cobras or Radial TAs.

 

The nittos have their place. You need really good suspension to make them hook beyond low 12's In my experience

 

Plus the Nitto's are a true street legal highway tire that is rated for sustained high speed Temperature A, unlike the MT's.

 

They would pick up with a real tire. Then, you're trying to compare them to ACTUAL all season, street tires? They're supposed to be drag radials.

 

Your just used to seeing people run 11s with Cooper Cobras with stock worn out suspension and 2.56 gears with 1.8 60s driving it out of the hole LOL

 

Mark, FINALLY got my new purchase out Friday. E70/14, stock converter or even less w/T350 and 3.42 gear. Run effortlessly down the road. NO screamer and will get shown the tail lights by a bunch of late model stuff.

So now making notes on what I want/fixes/issues and will start taking it apart in November. BUT reading on here as also got me thinking about chassis work/suspension needs. "LEANING" towards more of the stock converter, mild tire 3.08 gear style stuff.