So i'm rebuilding the 350 chevy V8 in my garage for the Rat Rod (http://www.hotrodders.com/forum/my-...ct-145257.html). Nothing crazy here, I need something thats decent on gas and reliable, while I want it to be powerful its not to big of a concern, the vehicle will weigh about 2400lbs have a borg warner 4-speed and 3.08 rear end. So even a 300 horse V8 will still make it one hell of a ride.

But I have two sets of cylinder heads, 882's (casting# 333882) and 193's (casting# 14102193). Both have 1.94" intake and 1.50" exhaust valves but the 882's are the first of the 'smog' heads, they flow well and are not the 'lighter' castings, but it does have the larger 76cc chambers, which means I will barley break 9:1 compression ratio with the thinnest of head gaskets. On the other hand the 193's have 64cc chambers and with standard head gaskets i get about 9.7:1 comprsion ratio, but they are the TBI 'swirl port' heads, their low lift flow is great for economy and torque but without many mods you cant get them to rev past 5000rpm. I have provided some flow data below, both at 28" of H2O and both with 1.94/1.50 valves.

882 heads
lift/intake/exhaust
.100-70.00-59.00
.200-125.0-109.0
.300-175.0-136.0
.400-204.0-143.0
.500-205.0-144.0
.600-206.0-145.0

193 heads
lift/intake/exhaust
.100-70.70-47.80
.200-124.0-85.10
.300-146.5-112.3
.400-154.7-125.0
.500-160.4-129.5
.600-(flow is not aval.)

I have the DYNO2000 sim and the predictions are as follows:
355 with 9.67:1cr, summit 1103 cam (http://static.summitracing.com/glob...s/sum-1103.pdf), with Offy 360 intake and carter perf series 625cfm 4-bbl. HEI ignition and 1.5" block huggers with 2.5" collectors running into a 3.0" y-pipe and a flowmaster 80-series muffler.
300hp at 4500rpm
380lb/ft at 3000rpm

OR if I were to do the exact same set up just with the 882 heads, which would drop the cr to 9:1.
330hp at 5000rpm
380lb/ft at 3500rpm

PLEASE NOTE: these numbers are approx. and at the fly, NOT the rear wheels... I only wish I had a 2400lb hot rod that made 330rwhp!

the 193 came off of a well running 93 chevy pickup, just a disasembly, cleaning and maybe a slight decking to flatten the gasket surface and they would bolt right on with no problems... but I HATE center bolt valve covers.

The 882 came off of a running 75 corvette but have been sitting, they would need to be dipped and cleaned also and I would have to get some valves or would the valves from the 193 heads work fine?

What would YOU do?

If the only reason you don't like the the 193's is centerbolt heads they make adapters for using regular valve covers, the only problem being you can run close to your brake booster.

I guess the center bolt valve covers are just a personal, cosmetic thing. I've seen the adapters for about 100 bucks or so.

It's really a matter of flow over cost/work. the 193 aren't perf heads but they will do the job and with very little work and cost to make them run but the 882 can be used as a decent perf head, atleast more than the 193s, but I would have to spend a few more bucks and a little more work.

Thanks for the suggestion though!

I'd be more inclined to use the lower c.r. if you don't plan to optimize the squish by either cutting the decks or changing pistons. With a wide squish, you may encounter detonation with the higher c.r. on pump gas. I'm not sayin' it WILL ping, just that it will be more likely to.

What I would honestly do? I'd sell both sets and apply the money toward a set of Vortecs. The chambers are so much more efficient than both of those that any money you spend (on the heads or the intake to match it) would probably be recouped over a year's worth of driving.

The 193s are really crippling. Sure, they're fine for low RPM torque builds (I have to say that so people won't be shooting arrows at me ) but they are very poor-flowing heads. They hit a wall at about 4000 RPMs and 250 hp. The cam you listed will be way too much for those heads. The heads will shine from 500-3500 RPMs and the cam won't start to make decent power until 2500. The heads will be done before the cam can even do its thing. I think that 300 hp is VERY optimistic with 193 heads. I'd say 225 max.

The 882s are the better choice of the two. The large chambers will require small domes to get in the 9's compression and domes kill flame front speeds. That means more ignition lead and less detonation tolerance. You might find yourself needing premium fuel for not much benefit. These heads will be an OK match with the cam, but they will start losing steam around 5000. The cam will be good to about 5800, so you'll be neutering some of the cam's ability but like you said, you're not worried about max power.

The Vortecs on the other hand will give you your higher compression, but the super-efficient chambers will let you run 87 octane with much less ignition lead. That translates to higher combustion efficiency and should translate to more fuel efficiency.

If you want to use what you have, go with the 882s. Try to get your compression where you want it using head gasket thickness, not domes. Tie a rope to the 193s and put them in your boat

"Tie a rope to the 193s and put them in your boat"

Curtis, I wish you'd stop hemmin' and hawin' around when you're trying to make a point.

Well said, I should have thought of that Their not that expensive either.

I wish I could get a set of vortecs, I even have a really nice intake for it I got a long time ago. I guess I could sell the Offy intake, 882s and 193s and put that money into some vortecs. how much do ya'll think I could get for both sets of heads and the offy intake? How much are vorte heads? I know new they are around $580 a pair assembled.

Could the stock 193 valves work with the 882 heads?

You'll be soooo much further ahead of the game by going with the vortecs.
Don;t bother with used vortecs. Buy new "12558060" assemblies.
Pick a cam with less than 465 lift and bolt them on without modification.
Especially if you already have a vortec manifold to use.
The Summit 1103 cam you suggested will make not less than 375 dyno HP and in excess of 400ft/lbs. on a flat top piston 350 motor.
Another good mild choice is isky #201264
Its also a bolt in with stock GM vortec heads.

If you want 400hp substitute this power full Isky .450" lift rule cam #201278.
All it needs is a set of Isky 205D hi perf springs minus the inner damper to replace the stock GM springs and you're good to go. Degree it in on a 102 intake C/L. Needs a high stall converter and agressive spark advance curve for best results. Be ware of excessive fun with this combo.

All will work just fine with stock GM 87 up self guided rocker arms.
The modest .450" valve lift of these Isky cams allows you to get the performance you want from OEM vortecs without further costly valvetrain modification and machineing.

CHP did a series starting with a Goodwrench 350 that used open chamber heads very similar to your 882s. With a thin gasket and a cleaning pass on the mill, a pocket porting job and a Comp XE268H cam, with an aluminum two plane intake and 4 barrel plus shorty headers they pulled 335 around 5 grand at the flywheel. Compression was around 8.5 with OEM round dish pistons that even had 4 valve relief cuts in 'em.

Makes your dream wheel calculations look reasonable.



Bogie

I actually have a set of used vortecs for sale, but they are ported and modified for .550" lift. Kinda pointless for you to give me big bucks for heads that are overkill.

I have bought used Vortec heads for $300 a pair and got lucky. I also bought some for $350 and they needed a $250 valve job before using and it killed the deal. I recently lucked on a complete vortec motor for $50 that I don't think had 10k on it before it spun a rod bearing. Buying used is always a crap shoot, and like you said, they're only $580 new.

How much do you want for them? Wait... better ask tis first, how extensivly are they ported? gasket match and bowl shaping? or bigger?!?! I have a comp 12-250-3 that might go with them... but it would make that engine scream!

This thread has moved very close to advertising. Please keep any further "offers" to the "Private message" feature. Thanks guys!

Mark

__________________
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You stated some goals of miliage and reliability.
The goal of achieving a low HP engine in favor of low speed Torque will make this an enjoyable engine package.
I myself would essentially build a Truck engine.
The 193 heads are an excellent street performance head that make UNREAL low speed throttle response.
A small bore 2 BBL intake off of a 283 would also work very well on the street.
I personally would use a stock 305 cam for the low base circle & tight overlap.

This will all make the engine run out of gas in the mid 4,000 range but will more than make up for any discrepentancy in high revs with OUTSTANDING low speed response, high vacum, & fuel effeciency.

No problem, Jmark. I know not to sell which is why I didn't list a price or specifics