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Discussion Starter · #1 ·
Hello,

I was looking for some advice in regards to the camshaft I should run in my small block. It had a solid flat tappet before, but i will be going to a hydraulic roller. Here is some info on engine components, car and use.
Engine- 4.060 x 3.562 forged crank
6" h beam rods
11.1 flat top pistons
(pre Platinum) Dart Pro 1 215cc 2.05 x 1.6 valves
Victor Jr with 750 mighty demon
Car- '55 210 del rey 2dr sedan, street/strip use, 3.89 ford 9", BW ST10 with 2.20 first gear(sucks), may go to a T5 when my wallet reaches the size of my hopes. No power anything, vacum and idle quality are not of concern.
Should I run a solid again?, is the roller worth the extra cost, this would be a retrofit application. Anyway here are the specs from Lunati and Bullet cams. Any advice or suggestion would be greatly appreciated.
Lunati - Lift is .598/.603 with 1.6 rocker, dur @050 is 243/251 with 110LSA
Bullet - Lift is .612/.612 with 1.6 rocker, dur @050 is 253/261 with 110LSA and INT C/L 106. Both hyd roller.
I feel I dont have enough gear for either one, so with that in mind in bump up to say a 4.11 - 4.30 whats best.
 

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There might be 15 hp between the cams, bigger one more of course. And there might be 1-2 mpg between them, bigger one less of course. Going from 3.89 to 4.11 is not much change, 4.30 would be more noticeable. The gears would do similar things for the torque at the rear wheels and gas mileage as the small cam/big cam thing.

Because of the motor oil situation, I'd go for a roller cam if your budget allows.
 

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Maybe a solid roller?

With the weight of a retro fit hydraulic roller takes a lot more spring for anything beyond 5500 R's. Not to mention cost of retro fits. Race Gas with 11 to 1's?
 

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Good point.

How do you get 11:1 with flat tops? Good news is you probably can't, and that's a good thing because you don't want to run race gas.

Also a T5 trans sucks even more than a 2.20 low gear 4 speed.

With the bigger cam maybe you can run more than 5500 rpm but not much, and you wouldn't want to, unless your goal is to say you did. You'll definitely need some good valve springs.

Think harder about where you spend your money to balance the combination to keep it practical and reliable.
 

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Discussion Starter · #5 ·
Rick I apologize but I rounded up. Probe #14210 -4cc 60 over flat top two valve relief with 64cc head would give me 10.6. I assume the heads will be milled when rebuilt so maybe a bit more. I appreciate the advise for cam selection, gearing and tranny. I see the T5 in ecklers and always wonder, thanks for setting me straight. Odds are I'll go for the shorter lunati grind and take some tire out of it for now (30") down to 26". Again thanks for the suggestion.
 

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I wouldn't even consider building a flat tappet engine today. Yes, the roller retrofit will cost money...so will rebuilding a motor if you eat a lobe on a flat tappet cam with today's oil.

I'm confused as to why you couldn't and wouldn't want to run more than 5500 RPM with either cam. Both are going to peak well above that RPM and even factory rollers can handle 6K RPM. Did you mean 6500 RPM Rick? That I could certainly believe.

Both of those cams are pretty big in a relatively small engine so you're gonna want to wind it up I'm assuming. I think the second one is solid roller territory. You're gonna need good springs in either case and good lifters too. I'm having a 421 built right now with a hydro roller probably closer to the smaller one you posted and my builder said Morels or Cranes (lifters)...both are good, but not cheap.
 

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Hello,

I was looking for some advice in regards to the camshaft I should run in my small block. It had a solid flat tappet before, but i will be going to a hydraulic roller. Here is some info on engine components, car and use.
Engine- 4.060 x 3.562 forged crank
6" h beam rods
11.1 flat top pistons
(pre Platinum) Dart Pro 1 215cc 2.05 x 1.6 valves
Victor Jr with 750 mighty demon
Car- '55 210 del rey 2dr sedan, street/strip use, 3.89 ford 9", BW ST10 with 2.20 first gear(sucks), may go to a T5 when my wallet reaches the size of my hopes. No power anything, vacum and idle quality are not of concern.
Should I run a solid again?, is the roller worth the extra cost, this would be a retrofit application. Anyway here are the specs from Lunati and Bullet cams. Any advice or suggestion would be greatly appreciated.
Lunati - Lift is .598/.603 with 1.6 rocker, dur @050 is 243/251 with 110LSA
Bullet - Lift is .612/.612 with 1.6 rocker, dur @050 is 253/261 with 110LSA and INT C/L 106. Both hyd roller.
I feel I dont have enough gear for either one, so with that in mind in bump up to say a 4.11 - 4.30 whats best.
If your using an OEM block make sure you sonic test the cylinders for thickness, I sonic test a lot of OEM block and its rare to find one that will go .060 over it only takes one cylinder to fail and you block is junk.

Plate honing is a must!!

If your using an old block make sure lifter bores are check for wear and sizing and make sure you don't use the cheap roller lifters with the .700 wheel.

Those are pretty big cams with a lot split and will require more RPM for to achieve peak power and the 4.30 gear would be a good choice.

I use steel cam cores with a the ever wear Dist. gear which are more money and most HYD roller cam core are a cast core.
 

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Discussion Starter · #8 ·
Block is from a 1970 c10/20 already 40 over and has been sonic tested and passed for 60 over. I will run the morel lifters. I read an article about an engine master challenge back in 2002 where the limit was 366 cubic inch, joe Sherman from so cal ran a cam in the 230's at 050 for peak around 64-6500 rpm. Same stroke, compression and intake volume for heads. Instead of using the online forms at the cam websites, I should call and speak to someone where I can go into more detail. Thanks to everyone who replied, I truly value the opinions.
 

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Those are huge cams for being hydro rollers! Seat to seat durations gotta be way over 300 degrees. Is that bullet cam really recommend for your combo by bullet?
 

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Discussion Starter · #10 ·
Yes, James from bullet cams sent me the info, this is the order/part number
GRIND CHS308/318HR110+4
MASTERS HR9 HR10
 

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Lunati - Lift is .598/.603 with 1.6 rocker, dur @050 is 243/251 with 110LSA
Bullet - Lift is .612/.612 with 1.6 rocker, dur @050 is 253/261 with 110LSA and INT C/L 106. Both hyd roller.
Either one of those cams is going to be....
1. an expensive build
2. murder on valve springs
3. screamers, that's just it...high rpm screamers

It sounds like you want to build a race motor and leave most of the 'street' part behind. That's ok but once you open up the wallet make sure too keep it open cuz your motor is going to demand it. If the race idea is what you're after, why not step up and run a solid?

I know I'm going against the consensus grain here but it's easy to keep a flat tappet cam alive by first choosing the right one for your intended use, then pouring in a bottle of ZDDP with every oil change....no biggie.

Good luck with your build, and I would sure like to hear it when you get it running.
Dan
 

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Discussion Starter · #12 ·
After speaking withthe machinist and comp came the decision has been made to go with a solid roller 248/254 @050. 3000-7000 rpm range. Most of the parts beside pistons and valvetrain are being reused from a previous build so the money is going towards machining and valvetrain . Car is for weekend use only out here on the coast should be fun when done.
 

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I have found that if going with solid roller on the street buy the best you can as solid rollers don't live thousands of miles on the street. I would suggest isky red zone lifters if you must use solids otherwise i would look for a good hyd roller option. JMHO
 

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I have found that if going with solid roller on the street buy the best you can as solid rollers don't live thousands of miles on the street. I would suggest isky red zone lifters if you must use solids otherwise i would look for a good hyd roller option. JMHO
The problem I have seen with the ISKY lifter is they are under size appox..001 or so and are to loose in a stock block with short lifter bores is even worse.
 

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even factory rollers can handle 6K RPM. Did you mean 6500 RPM Rick?
A factory roller is built to be easy on components. When you increase the duration by 30-40* or more and increase the ramp rates, you need better springs, a lot better. And you need to check them somewhat regularly. So I'll stand behind what I said. You need all the good components, including the cam core recommended.
 

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Discussion Starter · #16 ·
Just an update on the build, I've decided to go with an lq4 from 2003 silverado. Selling off the dart heads and other pieces from original build to finance the new engine. Wanted to thank everyone for the input and making me face reality that the old combo won't make the power where I want it.
 
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