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Discussion Starter · #21 · (Edited)
The Block is like new inside, stock bore and not munch of a ring grove. The heads on the box they came in said 68 CC, guide plates, seals etc, and the heads are new and had a port job too. Ok, sounds like I use the 350 turbo trans, I will use the stock steel crank..and stock length rods . thanks for all your help.
Duker
 

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You're making it difficult by not answering my questions, so I will assume the block deck height is 9.025".

You cannot use the original rods because nobody makes a piston for that rod length (5.565") anymore. You will need different pistons with dishes to keep the static compression ratio low enough to run pump gas without the motor detonating.

Because you have to use a longer rod, you will have to use a special rod that is clearanced at the big end to prevent the rods from crashing into several of the cam lobes and ruining the fun.

If you want to run 5.7" rods, use piston part number Keith Black KB147KTM, rings included, and Scat 5.7" rods, use rod part number 942-25700 available at Jegs.

If you want to run 6.0" rods, use piston part number Keith Black KB130KTD/KTM, rings included, and Scat 6.0" rods, use rod part number 942-26000 available at Jegs. Includes additional safety ring to prevent ends of oil rings from snagging in the wrist pin hole.

Gap top rings at 0.028". Gap 2nd rings at 0.020". Oil ring rails should be gapped ready to run.

Use Fel-Pro SFL1094 head gaskets. Clean block decks and heads completely and install gaskets dry.

New purchase intake manifold Edelbrock 7101 Performer or Weiand 8150 Speed Warrior. Used intake manifolds on craigslist, ebay or other used parts supplier 7101, 8150, Holley 300-36 Street Dominator or Weiand 8014 Stealth. All these manifolds will produce maximum torque and horsepower on a small block Chevy street motor.

AIR GAP INTAKE MANIFOLDS NOT RECOMMENDED FOR USE ON STREET MOTOR.

Static compression ratio will be 9.66:1 and squish/quench will be 0.035".

Use 1 5/8" or 1 3/4" long tube headers with 3/8" thickness flanges. Thinner flanges will warp up like potato chips from the heat of operation and spit out the gaskets. Install "H" pipe between the main pipes immediately after the collectors and use 2 1/2" tubing to the rear of the truck. Do not terminate the tubing under the truck or it will reverberate against the underbody sheet metal and sound like a mickey mouse exhaust system. Run the pipes to the rear of the truck, just past the bumper.

Motor will need 700 / 750 carburetor. Vacuum secondaries drive easier than double pumpers. Use a 14" x 4" air filter element so the motor can breathe.

Set initial spark timing at the crank at 12-16 degrees. Play with it and see what the motor likes. Reduce centrifugal timing so as not to exceed 34 degrees total, all in by 2800. Use manifold vacuum to run vacuum advance, NOT PORTED ADVANCE.

https://www.jegs.com/

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Techinspector, you raise a valid point. I had not realized that finding a stock rod length 400 piston had become such a rare animal. I found UEM/Silvo-Lite has just 1, a 5cc flat top in the claimer line with a 1.565" comp height, #9907HC.

There is just nothing with a big enough dish for pump gas, 400 SBC, and the short stock 400's 5.565" rod....everyone today uses at least the 5.7" rod length when they do a build.

Can't say that I blame them.
 

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everyone today uses at least the 5.7" rod length when they do a build. Can't say that I blame them.
Here's a blurb from Iskenderian on Isky Tips 2005 that may interest you......

"In fact, this may surprise you, but I know of a gentleman who runs a 5.5" Rod in a 350 Small Block Chevy who makes more horsepower (we're talking top end here) than he would with a longer rod. Why? Because with a longer dwell time at BDC the short rod will actually allow you a slightly later intake closing point (about 1 or 2 degrees) in terms of crank angle, with the same piston rise in the cylinder. So in terms of the engines sensitivity to "reversion" with the shorter rod lengths you can run about 2-4 degrees more duration (1-2 degrees on both the opening & closing sides) without suffering this adverse affect! So much for the belief that longer rod's always enhance top end power!"
 

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Yeah, I've read the whole Isky thing on rod length. Good read. All his Tech Tips are a good read.

The longer rod is better for cylinder wall loading with the longer stroke of the 400 and 383 stroker, I think that's the main advantage rather than breathing and high rpm.
 

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Discussion Starter · #27 ·
thanks for your input...I am trying to take care of all different way to go. 35 years ago you did not have many engine shops thinking on stroke of a motor, so many new tech ways to go now. Thanks Duker
 

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Get a 88-93 rusted out Chevy with a tbi 5.7, 2wd 700r4, and 3.42 or 3.55 8.5 out back for around $800.

Pull the harness, ecm, axle and transplant them in the truck loosely. Or run a standalone ecm. 88-93 have a small cap HEI design which makes them easier to fit then the large cap models.
Give the engine a rebuild with a 10 over bore and stay close to factory cam specs. Rebuild the 700 with a stage 1 kit. Replace the bearings, seals, and brake hardware all around. Just refresh things staying away from extremes.
Keep cold weather and junk 87 fuel in mind. Rebuild the throttle body with new sensors lines. Cap and rotor and such just keeping everything stock or slightly above so that it is happy.

Should be able to get 14-16 towing flat and around 8 on the aggressive hills/in town.
While those numbers may not sound amazing know that we are talking about a $400 engine(if you were buying the engine in a yard/list) with a $800-1000 rebuild that is fuel injected and won't give you jetting fits when your somewhere like halfway up a mountain in Pennsylvania. Thing also has a single serpentine belt with self tension so no belt squealing or adjusting.

These motors are simple with low compression to run on junk gas. Yet the torque around 280ft/lbs @2500 is where you need it for a truck. Mated to a 700r4 with 3.42 or 3.55 rear end the thing keeps the rpm and stress on the engine low allowing a simple rebuild to last you 150 to 250,000 miles with basic maintenance.

By buying the entire truck you get all the little things that add up like accessories and wiring. While it is a good idea to refresh and test these things. Your not starting from scratch buying everything bran new and figuring out how everything needs to be engineered to fit together the best way.

I have and still do 500 mile round trips over a 2 day weekend to go to an event(usually a big car show). Feel like going to Indianapolis, Chicago, Columbus or anything on a whim I will just go. I have had break downs from time to time. Being able to go into a parts store in any State and say you need parts for a 1990 Chevy 1500 and get the part you need that day to replace something basic like an alternator, starter, fan clutch, or front caliper that is sticking keeps the small problems from becoming big issues.

While it is nice to say you have 350hp under the hood and feel that power when you slap that skinny pedal down. For something made for long trips like your describing low horsepower, low stress, the ablity to drive it anywhere in any condition, and get parts for it anywhere works better in my book.
 

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Discussion Starter · #29 ·
Hi Cerial, A NOTE IN MY POST, ( the tow truck is gone ) so the motors in question are going into my 1942 street rod truck ....thanks for your input, going with a 350 /700R trans depends upon r end gear, and 400ci SBC
 

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Yes I seen you were transplanting it. Instead of building a carburated 383 or 400 with speciality parts you could grab a tbi donor truck to have everything to keep things simple with a mild rebuild on the drivetrain.
Tbi tucks under a aircleaner nice leaving the rest to look old. It gives nice drive ablity in all conditions while only requiring little investment of additional time.
While a carb might be nice for general driving. If you plan for elevation changes you should plan for swapping out jets a few times along your trip also.
 

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Discussion Starter · #31 ·
Ok I can do that, but I have a Holly TBI and its adjustable on the fly too. I am eager to try it. So it can hidden under the air cleaner and not munch wires to deal with, just a frame electric fuel pump or I can use the ( fuel pump in the tank and return fuel lines ) I have now on the newer frame. My main concern is the cam duration and piston matching. I need to find the H-power/torque rating of the cam I have new in stock. If I wanted a lot of H-power/torque I just install a BB mopar motor.:pimp::thumbup::D
 

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Discussion Starter · #32 ·
So I like to give thanks all the inputs on the motor build up. Oh by the way the intake I have are the non air gap RPM type divided for better torque curve. I heard they perform better in cold weather (40-60 deg.) with less problems.
Duker
 
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