Block Strength, Merlin Aluminum

So my wife (the smart one) asked me if my short block would hold up to the proposed changeover from SSI 14/71 HH at 54% (40 psi) over to a "C" at around 100-115%ish over and 50psi. The block is the heavier aluminum Merlinn 10.2" with billet splayed caps. It has the big webs in the lifter valley. This is not the Merlin "lite", there are also two oil pan rail bolt patterns as well. It has the extra deep threaded head studs (2 inches into the block) and new Pro-Filer Sniper-X conventional heads. .903 lifters, Clark copper, o-ring block...

I won't be spinning the motor over 8200 or so.

The car is a 71 Camaro steel roof and quarters, 25.2 chassis, running in a local outlaw class. Bradco 400, all the usual stuff.

Will I be blowing things apart? I have a Dart iron block as well, but not sure if that would be more brittle....

Thanks in advance,
ScotttRod

 

bbc

the C will be a lot easier on the engine at the same boost level. Keep it rich and conservative on timing. It will go pretty fast before it gets hurt.
I know of a merlin lite with a D rotor that runs ok but it will push a headgasket.

You'll never reach near the potential of that blower without a solid KB/olds style block but it will allow you to make the most power with what you have.

 

I think that Merlin is good to about 1800 HP ( with a blower lots of torque) give or take a few and that screw can make 2700 HP with a good but safe tune up. I would sale it while it is still in one peace and get a KB Olds. Just my 2 cents. been there broke the main webbing on a Donovan and a Merlin with dart 360 heads and a D ssi 14 bought a KB olds and never looked back

 

Agree with the two posts above. I'd probably give the nod to a solid New Century block though over the KB if you are going to buy new. You may be surpassing that 50LBS at that overdrive pretty quickly. No matter what block you run, you may want to consider starting out with 80% to 92% over. This is a C and not a D and I have seen over 50LBS at 92% over with a C. Butch on here runs a pretty conservative deal at a lot less overdrive in a dragster and he is flying with that. He also runs a New Century block if I remember correctly. I run a KB block.

 

Is the solid block mandatory? As crazy as this sounds, I take this to car shows and an occasional cruise (it is licensed and insured ;-). I talked with New Century, very helpful.

 

For sure it's not mandatory but if you are looking for maximum strength and durability it's the only way to go. If you want to street drive it some, you can keep it rich with the barrel valve and it will stay cool depending on how you drive but you will probably wash down the rings and dilute the oil. The PSI C is meant for business as well as the D. You are going to have to make a choice which is more important to you. Good luck.

 

New centrey blocks

We have been running the new Centrey Blocks for 7 or 8 years now and I have to say I could not be happier!!! Lowell is a stand up guy and knows his product!!! I have made every mistake possable on tuning and I have not had to line hone/bore any of my 3 motors ever!!! everytime we pull the motor apart and check it, it never moves, i think that has to say a lot to the strenth of the block!!! no checks, no repairs, no saddles needed.

We started out with a old 8-71 blower then went to a 14-71, then to a 206D and the blocks have held up very well, We run a max overdrive of 92% and we have seen boast up to 58 lbs, But boast is just the backed up unused air in the manifold and we do not run the best heads in the world, so at 92% over and other motor combo ( heads the flow better) could show a lot less boast, but make a lot more power then us.

But back to Scotts question, will his old block handle the new blower set up? If he runs the same boast as he did with the 14-71 (40psi) It will not be any harder on the lower end of the motor and the car will set up, do to the screw blowers are so much easier to spin at any gaven RPM, But to add 10 lbs more boast? that maybe a good question for the tecs at Merlin? also should make sure the crank, rods and the rest of the rotating assemble is up to the increase of power!!!

good luck

Butch