firechicken_3

iTrader: (4)

Hey folks, looking for a little input on heads cam intake here

engine is an older drivers side dipstick 2 bolt, has been rebuilt i was told .030 over if i remember correctly it has 4 valve relief style pistons standard issue felpro head gaskets and 993 heads on it which are 75cc chambered 1.94/1.50 from what i can find

cam specs are unknown, seems like an rv cam and since it was in a truck that makes sense... almost no lope very smooth idle


im looking at doing something different needs to run on pump gas, and be reasonable, i dont think i want to mess with the bottom end right now as it only has 40-50k on the rebuild but im open to changing cam

car is carbed with t-5 and 3.73 approx 2k rpm highway cruise

im thinking vortec as they seem very affordable these days and i would really like to go to a centerbolt valve cover for better sealing and cleaner plug wire looming

but can't seem to find consistent specs on my current heads to compare

good price for vortecs?

http://store.summitracing.com/partde...5&autoview=sku

EDIT do vortecs use standard SBC headers ?

Atilla the Fun

You probably have around 9.3:1 right now. The vortect would put you around 10.3:1, and that means premium gas and octane booster. If you spend $540 on vortecs. Or, you can Spend $700 for a new pair of bare Brodix IK180 aluminum heads, 64 or 70 cc, your choice, from www.competitionproducts.com. They have the 2.02/1.60 valves for $80 for all 16, new, stainless, swirl polished.
Plus you save 50 pounds. I'd say they're worth it, partly from not needing a Vortec-specific intake.
Do you want to keep your stock hood? Then forget the RPM AirGap. Do you have emissions testing? If so, you can either do the Edelbrock TPI Vortec base, or GM's $260 Performer-equivalent carbureted w/ EGR, or similar TBI with EGR, intakes.
Basically, if you have the smog test, the price difference in intakes alone makes up the price difference in heads, and the weight savings is free.
Cam: With any of these heads, go dual-pattern.
If street fun and good mileage are your thing, a nice, mild, and clean-emissions cam would be Comp's X4 254 H 11.
If you want a noticeable idle and have more rear gear, Id say Comp's DualEnergy 265 H 10. Everyone else will say these are sissy cams for any 350. But they're plenty big for the heads you have. For a non-emissions setup with 3.73:1 gears and better heads, I'd suggest Comp's DualEnergy275 H 10. With the Brodix heads, it's capable of 420 horses by 6000 rpm. How much farther would you want to push that essentially stochk short-block?
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By the way, I am a professional automotive machinist, and we really hear it from our customers when we choose the wrong cam. In my first year, I ate 5 cam changes, running me hundreds of dollars for cams that were too wild. But I learned.

five7kid

iTrader: (14)

A bunch of people are running RPM Air Gaps under a stock hood. Just need a drop base air cleaner.

993 heads are junk. Don't bother figuring out what they spec - they are completely un-spec-tacular.

The Vortec heads you listed are bone stock. Poor valve springs, very limited lift. Much better deal: http://www.sdparts.com/product/SD806...RPMAirGap.aspx

CR depends upon your deck height and head gasket thickness. With typical gasket volume and .040"-ish quench height, you'll be at about 10:1.

Add a Comp XE274 cam, you'll be running hard.

firechicken_3

iTrader: (4)

atilla that reads like a summit or jegs commercial thanks for the link to the heads it is something to consider staying with a traditional gen 1 head, and putting money that would be spent on an intake on the heads...

five7
i had seen the modded vortecs somewhere and now i know where it was...
and if you break down all that you get its a great deal

care to take a stab at potential horsepower with that combo? if i had to guess at hp currently i would say 200 or so

do you happen to know where i can get height measurements on say a edelbrock performer vs the air gap? or at least the air gap and how to measure the height

also of note, a friend that was there when i had the motor apart believes that the pistons had 4 valve reliefs and were dished.... any guess what compression ratio with that style piston?

obviously lower which would aid in pump gas running.. i would buy premium if i had to for no more than the car is driven, but would prefer to stick to 89-91 premium here is 93

firechicken_3

iTrader: (4)

ok so i feel pretty good about being able to use an rpm air gap...

according to edelbrocks site it is 4.72in carb base height, and the performer i have is 4.05in so less than 3/4inch taller than my current standard performer...

i have a 1/2 inch spacer between the carb and aircleaner now, and an 1/8 in plate under the carb to get linkage clearance on the egr blockoff plate....

about that cam..... have you actually used it? whats the idle like? and will a 600 cfm holley be enough for this combo to perform?

five7kid

iTrader: (14)

I don't personally have that cam, but I do have the XS282 in the 396. Idle is not "smooth", but tolerable.

In a 350, XE274, RPM intake, upgraded Vortecs, good exhaust, you should be putting out about 325 HP, compared to factory ratings.

firechicken_3

iTrader: (4)

first off sorry for poor punctuation


well, i snagged a motor to use in this build. scored a tbi 350 from a 90 half ton 4x4, pickup its a 638 block, and 193 heads (wont be keeping these). 1 piece rear seal. for $100.

engine felt smooth and felt decent compression when we turned it over with a bar, gonna take it apart this weekend to see how good it really is.. gonna get the short block rebuilt, grab the vortec head intake package from sdpc, and im still very undecided on cam choice, the reason?

i went a bit overboard on the cam in my old 305 looking for the lopey idle, it was like 280/290 duration and .450/.460 lift with dish pistons, and 416 heads, i assume i had more cam than the compression ratio could support.

so anyhow, i want to try to match the parts up better this time. i would like a bit of lope in the idle but dont want to sacrifice overall performance.

car has a t5 with .63 overdrive and 3.73 rear, 1 5/8 hedman shorties, single 3 inch and dual out muffler, currently has a 600cfm holley on top, which i realize may not really be enough if i need bigger i will do it

mileage is not of great concern, but i would like to stay reasonable for the event i want to take a roadtrip in it or something say 15mpg highway? in town doesnt matter to much

no emissions testing here in iowa, not even a visual.

the xe274 has been suggested, and i have read many accounts of it, and in this very thread both smaller and larger have been suggested.

i'm open to roller cams if the block is machined for the factory roller stuff, and the cam can be used with it, the aftermarket roller lifers are a bit out of budget on this one, trying to do it under $2k, should be doable as the average shortblock build only runs about $500 or so around here

would like opinions on cam and compression ratio, please explain why, rather than just shouting out a grind, if anyone has audio of their choice i would like to hear it.

thanks for taking to to respond if you so choose, looking for a little guidance before the machine shops tell me what i need

Atilla the Fun

I wish every post was as clear and concise as what you just posted. Plenty of details and to the point. I have to mention the odds are you will break the T5.
I suggest the GM "hot" cam, the one advertised as 218/228 duration at .050", 112 lobe sep.
In a 9.1:1 Vortec 350, with Edelbrock RPM AirGap intake, and headers, this is good for 385 ft-lbs from 2600 thru 5400 rpm, 401 HP @ 5600 rpm, and 428 ft-lbs @ 4200 rpm.

firechicken_3

iTrader: (4)

thanks atilla

concern over breaking the t5 is understandable, im not that worried about it though.

stuff happens, i have 2 spares in the garage so i can get by for a while.


is that hot cam a roller or flat? link to it somewhere?

will the 600 holley be enough to feed something like that?

still unsure on it being machined for factory roller setup, didnt get it apart today, hopefully sunday

Atilla the Fun

The "hot" cam is roller, the PN depends on whether you want just the cam, or if you want it with springs, retainers and GM 1.6:1 roller rockers. There's a 99% chance your block is machined for it. The RPM AirGap does better with larger carbs, I would run a Demon 750 annular for mileage with top-end power. A Street Avenger 770 would also work well, or if you prefer Edelbrock, an 800.

firechicken_3

iTrader: (4)

thanks again attila,

the block is capable of the factory roller gear, ran out of time and didnt get the pan down to see 2 or 4 bolt, engine is well worn, but appears to be untouched so should be plenty of meat to get the bores straight and clean