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Tech / General EngineIs your car making a strange sound or won't start? Thinking of adding power with a new combination? Need other technical information or engine specific advice? Don't see another board for your problem? Post it here!
Any good? I checked on mortec and all I see is "93-up 350 Gen I" which doesn't tell me a lot.
I've got a 350 I'm ripping apart and I'm trying to identify some pieces in it.
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"Beware he who would deny you access to information, for in his heart, he dreams himself your master"
'84 Black Camaro ZZ4 M5 (V-6 in a former life) -- street beast
'91 Medium Blue Metallic Z28 A4 (UB-HSTRY's old ride) -- currently broken
'99 Navy Blue Metallic Firehawk #120 M6 (99.44% stock) -- daily driver
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91 RS W/carbed 350, Vortec heads, performer rpm, Comp cams Xtreme energy 224/230 duration and .477/.480 lift. BFG Drag radials. 3.42 posi,Corvette servoed 700r4, 3000 stallconverter. Edelbrock TES, 3inch cat, flowmaster with single 2.5 inch exit.
Best time yet to come
12's?? :crossthumbs:
Uh oh...according to http://www.nastyz28.com/sbchevy/sbch.html They're 305 swirl port heads... That'd be easy enough to tell though by looking, not to mention i don't see how the hell that thing ran 13s w/ swirl port heads. I guess madmike's isn't as accurate as it used to be.
...ed
I'm not familiar enough with the 305 Swirl ports to know what they'd look like. I've seen about 6 different apps for these damn things and quite frankly it is starting to irritate me.
Off the top of my head, I've seen (that I remember)
93-up Gen I 350
86-87 Full Size Truck heads (HD)
84-85(?) 305 Station Wagon
They COULD be vortecs IF the heads were drilled so it would work on a TPI intake! My friend did that with his Iroc!!
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1986 Trans AM
305 TPI
200,000+ miles (speedo/odometer non-funtional! Odometer reads 142,000)
4 Wheel Discs
9 bolt Borg Warner Rear (2.77's....oh joy) :P
Completely Stock
Soon to upgrade to a 383 converted from TPI to Carb, Edelbrock 600CFM Carb, Edelbrock Performer RPM Intake, Hedman Shorty Headers, AFR 195's (if I can afford them), XE268 Cam, Moroso HEI ignition kit with external MSD Blaster II Coil and an MSD 6-AL Box!!
Current project: Keeping my 305 running until I get my income tax returns!
My best educated guess would be Truck heads. I'll see what I can find out!
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Working on:
'84 Z28 LG4 305 with 200,000 original miles!
Added dual elec fans.
145 MPH IROC Speedo
Building 430 HP 350 (ZZ430)
using primarily GMPP parts.
Short block sitting on a stand.
Hawk, when you get them off, you will know if they are swirl ports and will probably get a good laugh too. You can at least rule out weather they are swirl ports by looking underneath the intake valve to see if there is a big f**** circular piece of casting there.You can also look down the intake runner and you will see a big f***** piece of casting there too!!
If you do, well, ya got swirlports.
I just compared a set of 193 casting swirl ports to a set of 217 castings and I couldn't believe the difference.
You will be able to tell by looking at them.
Good luck..........bob
Well, wasn't it a surprise to run across THIS thread while doing a search! I figure I'll post a follow up while I have nothing to do
In case anyone cares, the heads ended up being traced back to an LO5 truck. They're swirl port, but not as bad as some swirl port castings (some sources labeled them as "low swirl"). I couldn't tell you exactly what the combustion chamber CC was, but it was less than a stock 71 350 in a 3/4 ton truck, which is what I ended up bolting them to.
If I may add my two cents here. I am a hobby engine builder. I came across these heads 10110810 about 2 weeks ago for pretty much free (20.00). I also has the same question as to what the heck they were 305 or 350 heads. Here is what I found out after 2 weeks every day of asking around and asking local machine shop in my area (West Texas).
The casting was reused for both 305 and 350. I asked how to tell and the most common answer I got was: if you have them removed measure the intake valve, if they are 305's they will have a 1.84 measurement, and if they are 350's they will have 1.94 measurement. Another way to tell is the "meat" or material between the chambers should be just under 0.5" (half an inch). Well I did just that yesterday afternoon with a new digital caliper I just bought. I got lucky and based on the info I got mine are 350 centerbolt heads. If you cannot remove or do not have your heads removed, sorry. In my area there was two mechanics (not engine builders) that said that sometimes you can tell a 305 casting and 350 casting by the way the casting number is situated on the head. 350 casting is vertical to the sides of the cylinder head. I would not put too much stock in this method but it is something to look at. Hope I made this clear as mud as we say here in these parts.
after a number of years, searching for concrete information on these heads, I finally was able to compile enough good data and wanted to share an update this post.
I have these heads on a 355 TPI. They are decent fuely heads that have a better a advantage over the other 2 swirl port heads 191 and 193. When combined with TPI heads you get a nice torque monster. 1991 Gen 2 Cast # 10110810 removed from 350 TBI Truck
Specs: 1.94 intake / 1.50 exhaust 64cc
sodium filled valves
flow 146 Exh @.500 (& 166cfm Inlet)
1.5:1 Rockers Hyd Valves
3/8 valve stems with rotator
Intake angled center bolts for TBI and TPI these apparently are considered to be the first generation of EFI swirl ports they don’t have as much restrictions as the others. note, my casting number is vertical and have the 1.94 valves.
Last edited by iroc-z383; Sep 21, 2023 at 10:26 PM.
Reason: Add picture of cast