I am begining a setup and i am probably going to have to turn my engine in the 6800-7000 rpm range? I wanted my setup to be a on a stock bottom but if i have to turn it this hard i want to make sure the bottom is going to hold it? I have had mixed assumptions on the power range for the cam i am going with. Here are the cam specs:

(taken directly off cam card)

3122S/3317s HR111+3
Vavle adjust ment: hyd/hyd
Gross vavel lift: .570/.540
Durration@.006 tappet lift 290 293
valve timing @ .050 :
intake open: 10 BTOC close 46 ABDC
exhuast open: 55 BBDC close:7 ATDC

108 ICL
durration at 050- 236/242
lift- .380,.360
111.0 LSA

236/242 with .608/.576 lift and 111 lobe serperation if you wana make it simple.

The heads i am running are Cmotors ported Lt1 heads that flow 278in./199ex. . Anyone tell me the power range for this cam and where i would have to shift this at to get the most out of my cam? I have heard from 6500 to 7200 so i dont know what to believe.

Also for my main question, if i have to turn the engine over 6800, what is the weak link in the bottom? I have heard the rods but im not sure. I want to know what i would have to do that would be the cheapest and easiest way to stiffen up the bottom if i have to turn it this high?

Thanks in advance.

Brandon

 

Rods are the weak link there. THe stock piston is pretty light but still once you start hanging out about 6800 that piston gets pretty heavy for a powdered metal rod. Personal preference is at at least get a set of Eagle SIR rods and rebalance the crank. While you are in there pick up a set of Mahle pistons and they will pick you up a few ponies.

 

Personally i would worry about rod bolts, and bearings.

With that being said, mine has seen 6900-7000 rpms TONS of times, and (knock on wood) no problems.

 

My firts worry in a high twisting motor is the oil pump. Often overlooked until it cavitates at high rpm. Just my 2 pennies.

 

atljar,

Is that all you did to your bottom and you turn it that high? Let me know a little more about your setup, if you want you can PM me. I am getting ready to start and i need to know the last few parts to purchase. How often does your engine see rpm's in that range? Also i havent seen many guys on this board running a cam with more lift on the intake than the exahust. What are your thought on this cam and setup. If you want to see more about my setup you can look here:

http://web.camaross.com/forums/showthread.php?t=275454

A few changes i have made though are as follows:

monoblade
K&N FIPK
4000 Stall
not P&P MAF just descreening it
vortech intake elbow
few other small things i think i am forgetting


I am already getting a new oil pump but can anyone direct me as to which one to get?

I need as many of these qusetions answered ASAP because i will have the engine out of the car by tomorrow.

Brandon

 

Rod Bolts!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!

 

I don't know about other opinions but the LT1 rods are actually pretty darn good from what I've seen. I know of several guys running the 95-97 LT1 rods in older small blocks and turning 7000 rpms at the races on each weekend. I would worry more about oil pump and bearings from what I've experienced. They are stronger than forged GM production rods.

 

MY bottom end is completely stock, but those two items i mentioned would be the first two things i would replace in a stock bottom end motor i expected to live. I drive mine knowing that it could let go at anytime, that just means my 383 goes in sooner, lol.

I see those kind of RPMs at least every other day. Ive been really good about oil changes throughout the life of the car, other than that nothing special. Mobile 1 every 2500.

Oil pump...melling. I think its part number mv55. You then want to get the white high pressure spring. DO NOT get a high volume pump

Your car...
Cam is odd. I love the intake look. looks like an XE lobe, but the exhaust lobe is different. I would guess it to be a very slow ramp, why not run two XE lobes? Rarely see less exhaust lift than intake.

Intake elbow = waste of money. Rip the screen out of the MAF, and port and polish it. As long as you have a tuner who knows what they are doing, you will be fine. More air in = more power.

Stall.... that will cause obd1 no shift. Do a search "obd1 high stall". Good luck

 

why no high volume pump?been running mine for 2 years no probs

 

Many of them will suck the pans dry. Complicates oil return path (more oil trying to fight through lifter gallery), more splashing on crank creating windage problems, overall loss of HP from driving pump and windage etc

 

I'd say either the oil pump or the pump drive shaft would be the weakest link. I don't mean the shaft itself, but the little plastic piece that holds it in place.

 

Oil pump is mandatory. As said before the Melling HV55 is a good choice, that's what I'm running along with an ARP driveshaft. From my experience with the SBC if something on the bottomend is going to let go the rod bolts are the first suspect. If you have the time & cash throw some good bolts in. So far I've been luck with the stock bolts.
As for the cam you've chosen I really don't see it needing 7,000 rpm, but you may be shifting in the 6,700 range.
Steve...

 

If you're interested, I've got a new (still in the box) Melling HV oil pump for sale. I'll sell it for less than Summit or Jegs. PM me. Thanks

 

atljar,

Bryan at pcmforless has a solution for a high stall in an OBDI car. The ECM in some cars will detect a tranny slip but in other cars it wont. If it does in my car, he said he had a solution for it. But you dont what to program this solution into the computer before you try it because it can end up hurting you in the long run. So im not worried about the stall. The reason i am getting the intake elbow is because mine has a large rip in it so im just going to go with a polished one for looks.

I agree with the rod bolts, but i havent heard much about the bearings. How much are bearings and where can i get some decent ones? Rod bolts too, where and how much?

Thanks to everyone who posted a reply

Brandon

 

TTT , Sorry but i need to get some questions answered ASAP

Is this the pump i should get:

http://www.cantonracingproducts.com/...s/melling.html

Part number #M-55?????

I am going to check for elongation in the rods when i pull the pan off. If they need to be replaced, anyone know a place to get a cheap set that would be ideal for my setup??? Also i need to know about the rod bolts and bearings that i asked in the previous reply.

Atljar,

What do you mean by i need to get the white high pressure spring? Can you guide me in the right direction for purchasing this?

Thanks again to all

Brandon