Engine rebuild

A decent stroker build will run you between 3000 & 3500 for the shortblock. Don't use inferior parts or inferior builders because the results won't be what you want, especially with a blower.

If this is your first build and you are serious about asking it to put up with some punishment (power adder, high RPM, endurance conditions) than I would have a really good (or seriously outstanding) engine builder build the motor. You run a very good chance of throwing away a lot of money on a failed venture if you try to build it yourself. Especially with the rod angles you are playing with with a stroker and the thermal dynamics involved in sealing a forged piston...especially with a blower.

I prefer 347s, I've talked with a number of industry builders (such as those at DSS and CHP) and read a number of quotes as well and it seems the most knowledgable builders are on the fence as to which motor is better between the 331 and the 347 but what I've found is that more of the builders tend towards the 347 (the controversy is whether the 331 seals at high RPM better and thus creates more power and lasts longer than the 347).

As far as the option to stay with the 302 or stroke it...well, a well built 5.0 can effortlessly exceed the power output the stock block can handle, and with a good power adder, the extra torque provided by the stroker becomes a moot point.

That said, I know a guy who was running his stock shortblock up to 210,000 miles with nitrous and hitting low 13s. So, unless you see some signs of shortblock wear (like smoking that isn't attributed to worn out heads) you may very well be fine with a supercharger on your stock motor (provided you repair any mechanical problems like poorly sealing cylinder heads).

If you decide to go with a new motor, use a good quench piston with a dish such as those offered by DSS: www.dssracing.com

If great sealing and longevity are required and low boost levels and power output (400 and below) are going to be used, then a quality dished hypereutectic will work fine.

Ryan

hookups333 said:

Well my engine has some mileage on it and i am wanting to rebuild it before i go with some type of supercharger. Where should i get the kit to rebuild it my self and should i go ahead and stroke it or stay stock 302 size? Also since i plan on a blower should i go dished pistons? And what all should be forged that i get? and if i do go stroker what size should i step up to without breaking the bank. Oh and i was kinda hopin to stay under 1000$. All help appreciated.

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As long as the engine doesn't have any tell-tale signs of wear like smoking, knocking or low oil pressure, you probably don't need to do anything. Those motors are pretty damned stout. The engine in my '93 has 160,000 miles on it and it runs like it has less than 60,000. My '95 GT has 107,000 and it doesn't use a drop of oil and I wouldn't know that it wasn't brand new if I didn't know the mileage.

Ryan

hookups333 said:

I didnt plan on getting rid of the block. I was just going to get new pistons and rings rods and that kinda stuff.

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306 might be the way to go for you with that budget. You can probably get some pistons ,rings,bearing, and bolt. along with the machine work. This will enable you to slap your blower on the car with less worries. it will at least freshen it up and thats what you want.
I would probably say that your going to need a bit more if you go to a better machine shop. If you do it at home stroker any kit is running about 1000 bucks. Girdles, oil pan, and since you will need new damper and flywheel in order to balance to 28oz is going to run about 1000. But dont let this discourage you if your car is still runnin just hold off and buy one piece at a time and do it right.

I would go with probably a sealed power kit from summit that should set you back about 350 bucks i dont think they are forged but its not a bad piece if you want a budget. i havent heard many good things about dss or chp ask around just dont ask them. they always say their stuff is better. your build should have a projected HP in mind and choose parts to match.

ask your engine builder you really have to see what he cut or polishes off the crank. You might want to throw in 50 bucks in hardware for your rods. You will be at about $500 with a new high volume oil pump. That will be a good base for you those sealed power pistons forged set is fair performers for the price. build it and run it dude...

You will need to have the machine work done to the motor so they can size the engine and the parts together...the kicker...they need the pistons, rings and bearings to machine the bores and crank correctly. If a machinist is willing to machine the bores without the piston/ring set up, find a new machinist. The parts purchase and machine work are best done at the same time to ensure proper fit. If the parts don't fit, the machinist can return them and you won't need to deal with. If you buy them yourself, then the onous is on you to get the right parts.

At the very least, have a good machinist take a look at your crank so that he or she can tell you what bearings they think you are going to need.

Seriously, if you have this many questions about how to build an engine you should have a good engine builder do it because screwing this up could cost you everything you put into this motor and then you will need to start over. It's less expensive to spend a bit more and do it right the first time than it is to have to do it twice.

That said, it's fun to build engines and with enough knowledge any one with the necessary skill set and desire can do it.

Ryan

hookups333 said:

I was looking at the rebuild kits from summit and they sound good to me but, how do i know what sized bearings i should get and all that stuff?

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Unless you are going to use a wide clearance on your bearings, do not use a high volume oil pump. Regular volume pumps in stock clearanced motors are good to a solid 6500+ RPM. High volume units in stock clearanced motors will at the very least rob the motor of power. At the worst they will blow the seal on your rings and cause excess oil consumption.

Ryan

yobi1kanobi said:

ask your engine builder you really have to see what he cut or polishes off the crank. You might want to throw in 50 bucks in hardware for your rods. You will be at about $500 with a new high volume oil pump. That will be a good base for you those sealed power pistons forged set is fair performers for the price. build it and run it dude...

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junkie is right about the engine building the machinist will ask you for the kit if he is a good builder. We arent just building grocery getters here they have to plate hone the block. But a builder should be able to tell you by looking at the wear your crank has developed. As far as the pump you can go with the std vol.. std pres.. but if you go with a 7 qt i would go with h volume...plenty of people i know have built 306--to--347 with hv and have had no probs they have had probs with high pressure pumps

hrspwrjunkie said:

Unless you are going to use a wide clearance on your bearings, do not use a high volume oil pump. Regular volume pumps in stock clearanced motors are good to a solid 6500+ RPM. High volume units in stock clearanced motors will at the very least rob the motor of power. At the worst they will blow the seal on your rings and cause excess oil consumption.

Ryan

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Also, you may end up having to get a larger oil pan to hold more oil if you use as a HV pump. The HV pump moves more oil.

Without going back and finding the quotes....

Just build whatever.

Don't worry about rod angles, thermodynamics, or any other of that technical junk. Those kits are designed to have the "right" rod angles and thermodynamic properties. Actually, I've never even heard of thermodynamics when talking engines.

If you stay with a 306 and you keep the same rod length, there's no need to use a HUGE dish if you keep the same (8.2) deck height. You could use a 4cc dish, and that would be plenty. The less compression you run in N/A form, the bigger of a dog it's going to be. And, when you slap a blower on it, you aren't going to run anywhere near the compression "limits."

Let everyone that reads magazines tell you otherwise but a 9.5:1 or 10:1 motor will run perfectly fine on pump gas and 10 pounds of boost. Once you turn the wick up past 10 PSI, you're at the limits of the block - not the compression.

Joe

hrspwrjunkie said:

As long as the engine doesn't have any tell-tale signs of wear like smoking, knocking or low oil pressure, you probably don't need to do anything. Those motors are pretty damned stout. The engine in my '93 has 160,000 miles on it and it runs like it has less than 60,000. My '95 GT has 107,000 and it doesn't use a drop of oil and I wouldn't know that it wasn't brand new if I didn't know the mileage.

Ryan

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Ain't that the truth. I say buy a low mileage "used" motor and call it a day. Then add on your power adder of your choice.
If it blow up then you can say ..."well I only paid $350 for this motor...." and put in another. A lift costs nothing to rent and it's at the most a 3 day job for a novice and about 5 hours average for a seasoned person with prior knowledge.
4 different power adders and a stock block with nothing but a few blown hg's. 174+K and still strong. I'll get 10's out of it this spring and this is the motor that came in my car when I bought it 5 years ago and the oil pan has never been off.
I will admit I expect it to go everytime I go out but that's just part of the fun of having 3 spare motors anxiously awaiting their chance to be abused.
All in all though as said already , these are some stout motors and I will vouch for that anyday.
btw if you click my sig, all the set-ups pictured have been on this same stock bottom and our horribly rumored crappy hyperutectic pistons. Which are fine pistons IMO.