I was thinking about the best engine for my project (again). Most important is plentiful aftermarket support, into the future. There's a lot of good engines out there, but when you are limited to a few suppliers who may or may not be there tomorrow, it's a risky proposition. Nothing worse than investing time and money into an engine, which then has a part fail and you either have to go to one expensive source, or worse no source at all. Small block chevy seems best to fit this criteria, as far as fiero engine swaps are concerned.

Second is for my project the personality I am going for is a high-winding engine. I love going to cruises and feeling the vibrations from big cube hotrods, but I don't want that for this project. Which leads me to a kind of dilemma. Most parts for a small block chevy are made for big cubes and strokers. I am looking for a big bore small stroke combination, which would additionally be supercharged (vortech or similar).

Core to this is finding a short-stroke crankshaft. The smallest I have found is 3", which I could build to a 302 ci. I think that's still too big, but I can't find anything lower that isn't a custom order (which would go against #1). Is anything smaller than 3" even practical (probably a better question)? I'm having trouble finding any info online about engines other than a 350 or strokers. I also haven't seen much in real life besides 350s. Would a 327 satisfy my need (3.25" crank)? I think it would still perform too similar to a 350 (ie powerband in the wrong place), but I don't know how to find out. It depends on the other components that make up the engine, I know, but generally the bore and stroke most determine the engine's personality and powerband. Can anyone give me some advice? Maybe a method/formula you've used, or some sites with info. I'm looking for anything at this point, other than "abandon this stupid idea." Those people feel free not to comment, unless you have a good reason

There was a great write up years ago about the GM 350 mistake. It's been a long time since I read it, but I think they author was talking about exactly what you are looking to do, short crank, large bore, long connecting rods. Apparently with the longer connecting rods they could run the engine at a higher compression ration (good for forced air!) and still run pump gas. I have no idea where to find the article, I know it's online floating around, but your idea is tried and true.

-Rick

It's been a few years for me regarding SBC's, but, as I recall, the 327 configuration is a REALLY GOOD one. You can rev them high and they rev easy. I don't know about supercharging them, but, they have been built to 350 hp with just a carb.

That would be my vote. I drove a 302 and it was not nearly the engine a 327 is. Hope this helps.

BTW you might want to try this website http://www.hotrodders.com/

Arn

A 327 sbc is just that, a destoked 350 SBC. It uses a shorter throw crank but has the same bore .


edit cause my english sucks !
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HARDCORE SBC CRONIE AND PROUD OF IT ! GOT TQ ?

[This message has been edited by FIEROPHREK (edited 06-06-2006).]

you could build a destroked 400 using a 350 crank but I personally would go much further IF POSSIBLE and use a 3.25 or 3.00 crank if journal spacers are availible and use custom long rods and pistons.Thta would result in a very oversquare highwinder with torque. An L99 3 inch crank could PROBABLY be used in an LT1 350 4 inch block if you wanted to go for later gen block with the optical crank position sensor

In 1975, Chevy offered a 262 cubic inch small block (even smaller than the original 265), which used a crank that had a stroke of 3.10 in (78.7 mm). I don't know if this is the small journal or the big journal crankshaft. A check of part numbers, e.g. for bearing inserts, should reveal that. Good luck.

How high winding are you wanting this?

Our 383 small block hits 7000 all day long, and still with generous amounts of low end.

I think you're making too big a deal of the stroke. It will not affect the revability as much as the cam, valve train, intake, and exhaust. NASCAR cup cars are turning 8k - 9k with a 3.5" stroke. Aaron has a 383 (3.75" stroke) that turns 7000. Many years ago I raced a car with a 383 turning 7200.

Pick your stroke to make parts easy to find and then pick your RPM range with other components.

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Doug Chase
Chase Race
Custom: cages, exhausts, fabrication
Duvall, WA
425-269-5636

I'll say right up front that this definitly isn't the diffinitive answer and it should probably be read critically, but nonetheless there is a lot of good info in this thread over on thirdgen.org

http://www.thirdgen.org/techboard/engine-swap/274673-327-350-fact-fiction.html

That's a good read ToasterMan. Thanks.

I still think the 327 is the better fit/power band for a Fiero weight.

Arn

I agree about the 327. If you're looking for a short-stroke, high-rev SBC, then I think the 327 would be the best foundation for such an engine.

Actualy, I did some experimenting in Desktop dyno with the different stroke lengths of SBC's and the 302 pushed the powerband furthest up the RPM range, then 327, then 350. All of these motors have a 4in bore. The shorter the stroke the less torque made, but power remained about equal just in different places.

Thanks for all the replies thus far.
FieroWannaBe: I know desktop dyno isn't the same as the real thing, but I wouldn't mind seeing the graphs of what they each produced (preferably overlayed in one graph)

As far as how high I want to rev, I hear if I can get it to 8000 I can go 200mph Seriously though, the higher the better up to a point. Really range of power is important, the longer I can do useful work in one gear the better. I am leaning at this point towards a 327, the cranks are easier to get as far as I have seen.

And useable work is really what it's all about. Even if a shorter stroke means less torque, being able to spin it higher means more work can be done. Add a supercharger on that and higher rpms results in even more work being done, than the same setup running at say half those rpms. I know (as the 383 illustrates) with the right parts you can get any size engine to wind up. The main thing with smaller stroke is it's easier on the parts (as easy as doing controlled explosions at 8 grand can be), which results in less wear (again, a relative concept) and generally cheaper cost. Again, most of this is theory as I haven't had much first-hand experience with small blocks. What Doug Chase says is probably true, I'm putting too much emphasis on stroke. I'd like some more info to confirm or deny that, so I can make educated decisions about the engine as a unit (I'm reading that thirdgen.org post right now). Thanks

Edit:
Oh, and if anyone has links to engine sounds of 302/237/350/etc, that would be great as well

[This message has been edited by kwagner (edited 06-06-2006).]

why not build a 4.3 V6 it fits in the car better and uses many of the same parts of the SBC same pistons cam bearings main bearings piston rings and if you superchage it or tubocharge it you can make great power you can even get racing heads cranks and rods ect if you want

If I was going to build a high reving sbc it could be a 350. made the odd way. 3.25 stroke,4.155 bore. Just my two cents. Plus a solid roller cam

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85 GT 3.4
Auto 3.08
14.9 @ 90 1.9 60"

a couple of years ago I made a 327 out of a 350. Found a large bearing 327 crank and built it with aluminum heads . I had 10.5:1 compression, an it would lift the front wheels of my landcruiser on the 2nd to 3rd gear shift.
My last 327 is a 1966 small bearing with the same aluminum heads but this time I have a roller cam. ($1000.00 extra) do a search for 327 iron butterfly. I suspect you'll be impressed.

If you realy want a screeming small block do this go get a 283 a latter one have it bored 125 over they will take it i have done it get some 302 chevy piston and screem it to 8000 rpm i did with a race car i had and it took it all day long with stock rods with good bolts and resized big end and floated pistons

quote Originally posted by DrDave: do a search for 327 iron butterfly. I suspect you'll be impressed.

400hp ain't bad Thanks for the info

If you are looking for an 8K motor, consider going with a 327 (small jorurnal) and convert to a 302. (Small Journal Rods have 11/32" bolts instead of 3/8" bolts on the Large Journal 327).

You will need is a set of 302 pistons, 283 small journal crank. The 302 is a 4" bore - 3" stroke motor.


As fas as "appropriate Block"

Blocks used in 1967 were casting number 3892657. Samll Journal. Also used for 327 and 350 cubic inch engines as well (all three engines used a 4.00" bore). 1968 models used block casting number 3914678 and had large journals.

The 1968 block was also used for the 327/210 hp and
the 350 295 hp SS engines. The blocks used in 1969 featured thicker webbing around the mains and used nodular iron 4 bolt caps. (very hard to locate these nowadays many of these blocks that are easily found are 2 bolt blocks but the 4-bolt blocks are out there if you look - and pay the $$$$). One of the 2 I built was a 2 bolt block and it held up very well even with pretty heavy abuse. A misconception is that 1967 and 1968 302's were 4 bolt blocks. Only the 1969 engine used 4 bolt main caps.

If you want the "exact specs" you can get the grind of the 69 Z-28 (DZ-302 grind). They are available at Summit Racing, PAW etc. They were originally factory rated at 290hp but those numbers were pretty underrated during that time period and were usually at the rear wheels not the crank) . You need the closed chamber 2.02 heads or equivelent (especially if you got with a bigger cam) . You'll have a pretty bumpy idle and should hit the 8K mark.

I've built a few many years back. Very nice motor. Durable. Depending on heads, pistons etc, you should Dyno in the mid 300HP range or bump up the cam (but not much), the 302 does'nt need much cam. You could punch it .030 over to squeak a bit more out of it but I find the idle tends to smooth out. Torque seem to come it a bit lower (just a squeak) and while I don't know if for sure, I feel they top out , RPM-wise a little sooner (7500 or so).

I think I have spec's and old cam #'s around here somewhere if you need them.

Hey Engineman, Can you go "125" on a 283 ?? I'm a BBC and Big Block Olds guy so I've only built about 8 SBC's. Mostly 355's, (2) 302's from 327, (1) 415 Super mouse (remember when they were "the in thing" ?) and a few 400's. Just curious. The bore is pretty small on the 283 but I never really thougt about it. I kept my Olds 455 in the .060 and .090 (on the track only car). I seem to remember the BBC guys going 110 on the track motors if I remember right. To much time away from it..

[This message has been edited by 3084me (edited 06-06-2006).]

quote Originally posted by DrDave: do a search for 327 iron butterfly. I suspect you'll be impressed.

Thats the article that got me seriously thinking about building a 327 ! I'm running the same cam and lifters with 1.6 ratio rockers stud girdles, a performer rpm airgap intake and world sr torquer heads. I'm running the same pistons with manley h beam rods and a forged crank. Desktopped at 479hp but i want real numbers so i'm taking it to the dyno within the next month . . . hopefully . I'll be happy with 400@the crank.

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HARDCORE SBC CRONIE AND PROUD OF IT ! GOT TQ ?

Looking forward to seeing the dyno sheet

All this talk of 302's brings back memories of going to Road America in Elkhart Lake Wisconsin in the late 60's and watching people like Mark Donahue and others go real fast in Camaros. Mustangs and Barracudas with 5 liter engines in the Trans Am series. What an Iincredible sound when they came around on the first lap all bunched together.

Yes 3084me the 283 has a 3 7/8 bore and 1957 and newer blocks had enough meat to bore them 1/8 inch to make a 302 the one i had in my race car had ported aluminum heads and a roller cam not to much low end power but screem on the top end

Just trying to come up with a price/parts sheet, if I'm missing something or have the wrong thing let me know
GM Performance bare block, 4" bore, 4 bolt main, 1 piece rear main seal (summit part NAL-10105123): $679.50
crank
heads
rods
carb

These were taken from the parts list of the "iron butterfly", where fiero-applicable:
keith black hypereutectic pistons, kb-156
rings, bearings, gasket set
rod bolts, 8740-style, ARP 134-6001
rocker studs, 3/8 inch, ARP 134-7101
cam kit, retrofit hyd. roller, Comp Cams k08-422-8
rocker arms, pro magnum, 1.52, Comp Cams 1301-16
cam button, roller-style, Comp Cams 200
harmonic balancer, 8-inch, GM Performance Parts 3817173
valves, street-flo, 2.02 int., Manley 10750
valves, street-flo, 1.60 ex., Manley 10749
pushrod guideplates, Manley 42355-8
performer rpm intake manifold, Edelbrock, 7104
msd-6al ignition box, MSD 6420
plug wires, 8mm, blue max black, Moroso 73231

Even more power :
Forged steel crank
Vortech supercharger kit for carburated small block chevys: $2800

Now I don't have prices for all those, and am somewhat afraid to find out. Which brings me to a question: would you:
a) get basic (cheaper) parts to create the base engine, get it in the car and running, then build it up in stages
or
b) don't waste money buying parts twice (or more), save up to have the best engine to start with, then put it in
I see arguments for both sides, I'm curious what you think and your reasoning.
Thanks for the lively discussion thus far

First thing build the bottom end to handle the power you want the motor to have. Balancing and machine work on parts you are gonna swap out is a waste. It is easier to upgrade the heads, carb, intake manifold with out taking the motor to the machine shop. I would look for a set of aluminum vortec cylinder heads and use some manely race-flow valves ( are swirl polished and necked down on the portion of the stem that is in the intake runner) . If your trying to make top end power go with a single plane intake manifold like a edelbrock victor for vortec heads ( p/n edl-2913 for 239.88 at summit) . I haven't noticed any forged cranks lately for a 327 with a one piece seal. If the block you are refering to has a one piece seal then it probably is already setup for a hydraulic roller cam therefore you can save the $400+ bucks on the retrofit lifters. You will need to make sure the lifter will handle the cam and not bind up on the locking plates. One piece pushrods are also a very wise investment as to them not having parts to break off such as the end pivot balls. Stud girdles will help keep the valvetrain (rocker studs and rockers) from wobbling at high rpm. The balancer is a no-go, archie's (if thats who's kit you use) comes with a special balancer. There are so many ways to build this motor it's making my head hurt

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HARDCORE SBC CRONIE AND PROUD OF IT ! GOT TQ ?

[This message has been edited by FIEROPHREK (edited 06-08-2006).]

for a good solid bottom end for cheap money buy eagle products kit gives you a 4340 forged crank je forged pistons 4340 h beam rods 6 inch rings rod and main bearing and balanced for about 2000 bucks then get a 4 bolt block you dont need a bowtie block get it decked bored honed and aline bored get some good after market heads like dart iron eagles with no bigger than a 200 cc intake port with a hydrulic roller came it will make good hp and work on the street you should be able to put a engine like this for about 3500 bucks and it wont let you down

Isn't the LS4 a 327? Why not start with that and use the Corvette Z06 top end and have a nice modern engine?

[This message has been edited by lou_dias (edited 06-08-2006).]

From the checking I did, the ls3 was a "396" but actually a 402.

engineman: Maybe you have a different source than me, but the cheapest I have found for eagle forged crankshafts is $600-800. But I guess if you want to play with the nice toys you gotta pay for them

On the previous subject of upgrade now vs later, I found these two sets in the summit catalog in my "morning reading":

quote These Holley SysteMAX street systems for small Chevy contain a Holley dual plane intake manifold, a Lunati hydraulic camshaft and lifters, a double roller timing chain and gears, and assembly lube. Gaskets and fasteners are sold separately.

hly-300-502, $333, systemax, advertised ~325hp

quote When you upgrade to one of these Holley SysteMAX II street engine systems for small Chevy, you get top-quality components designed to work together for dramatic results. You get fully assembled Holley cylinder heads, an intake manifold, and a Lunati cam with 235°/240° duration at .050, .490/.490 in. lift, and 112° lobe separation. You also get lifters, hardened pushrods, head bolts, a double-roller timing chain and gears, and assembly lube. These kits include everything you need to up your horsepower and torque, for performance you'll love.

hly-300-503-1, $1450, systemax II for 302, 327, 350, advertised ~400hp

Granted both sets of advertised numbers are probably 'best case' for a 350, I'd have to see how much different the loss of 23 cubes would be. They were listed in the catalog but not in summit's online store, so I don't have the exact numbers. But to have a complete 'known working' set for what looks like a good price is a good thing.

they sell complet engine kits for about 2000 all balanced i bought from eagle i think racer net for the kit i bought was like 1700 but i will need to look in one of my eagle catlogs lookin in the eagle catlog kit B12003 flat top pistons JE SRP forged with H beam rods Forged 4340 crank plasma moly rings Clevitte racing bearings and balanced $1906.25 this is out of my 2005 catlog price maybee a bit more now but i bet they dint go up only $200 if that and this is racer net

[This message has been edited by engine man (edited 06-08-2006).]

Here is a good example of a destroked V-8

http://www.falconerengines.com/prod05.htm

quote Originally posted by lodown1: Here is a good example of a destroked V-8 http://www.falconerengines.com/prod05.htm

i want one ..probably 50k or more though