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Old Mar 18, 2025 | 08:40 PM
  #1  
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Cam and heads

So ive been on these forums for a good number of years reading and learning, I've rebuilt a good chunk of my car and learned a bunch along the way. I am currently putting a fast sportsman in my car and learning how to tune which brings me up to my next step id like to take. I have settled on putting a Stealth ram on it next, i can mill it to size on my own just fine. I really like the powercurve and dont hate the way it looks. It would be awesome to just install it and go but i have a basically factory l98. its a rebuild and i dont know the cast number it got milled off but i was able to figure out everything i could about it. So with all that being said I need heads and a cam at the very least. I know i don't want a super choppy cam so i figured a 220 to 230 at .05 would be good bat am open to suggestions. I also need heads to do this and i am unsure if i need to get 195s or if their to big. any thoughts or resources for this would be great. Its not something im rushing into and doing so i have plenty of time to hear suggestions and do research. Ive seen plenty of 355 or 383 but havent seen a plain 350 build yet!
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Old Mar 18, 2025 | 08:59 PM
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Re: Cam and heads

Another factor that's important is that in the next few years I plan on doing a t56 swap with 4.10s or an equivalent to it. But that might take 2 years to happen so I can't have a super crazy cam and get surge real bad. I do drive this daily in the nice weather and do some good distance driving, I don't mind a loss in mpg but I don't need anything f*****g with me while im driving
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Old Mar 18, 2025 | 10:06 PM
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Re: Cam and heads

How much power do you want to make?

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Old Mar 18, 2025 | 10:36 PM
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Re: Cam and heads

I am confident 400 to 450 would be pretty okay for me, I mostly do street driving and like to have fun, don't need to be winning on tracks.
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Old Mar 19, 2025 | 03:40 AM
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Re: Cam and heads

havent seen a plain 350 build yet!
That's because usually when a motor is rebuilt, it's because it's already been worn out. Otherwise it would stay in the vehicle it's in until it's no longer any good. Just like your L98.

A "355" IS a 350. It's just one that's had the usual first incremental maintenance done to the block that is often required after it wears out; being bored out by .030" to clean up the wear. So don't concern yourself with that as far as "don't want", it's the same thing.

A 383 is a different matter. That involves also changing the crankshaft to one with the stroke of the 400 (3.75"), along with the slight overbore and different rods and/or pistons.

Before settling yourself on the Stealth Ram, make sure you can still get one, with any/all little parts & pieces needed to make it work. It's been discontinued for quite some time now AFAIK.

Heads w 195cc intake ports are roughly about the right size for a decent street 350.

​​​​​​​i can mill it to size on my own just fine.
Not sure what this is about... no milling is required, nothing to "mill to size"
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Old Mar 19, 2025 | 07:24 AM
  #6  
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Re: Cam and heads

I am fairly certain holley still sells stealth rams! They normally don't fit under a firebird hood without machining the top of it down or cutting the hood support out, both of which i can do. I'll have to look again but I was super confident that I saw HSR for sale still!
I am also aware of what's needed for a 383 and just don't think it's something I'm currently interested in right now. And I believe my block should be in fine condition to not bore it over a bit and be okay but that's good to know I didn't know much about 355

Last edited by Lordkdog; Mar 19, 2025 at 07:37 AM.
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Old Mar 19, 2025 | 08:08 AM
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Re: Cam and heads

but i have a basically factory l98. its a rebuild and i dont know the cast number it got milled off but i was able to figure out everything i could about it
No, the cast number DIDN'T "got milled off" unless some bozo was REALLY TRYING HARD to cheat you. The STAMPING, that encodes the application and VIN of the vehicle the block originally came in may have, but not the CASTING number. Here's what it looks like. It's located in the most convenient possible spot on the block, conspicuously right out in the open and easy to read. [/sarcasm] Top of the bell housing flange behind the driver's side head.



I believe my block should be in fine condition to not bore it over a bit and be okay
Unfortunately, "believe" isn't very convincing to metal parts. In any case, more than likely, it already HAS been bored, since

its a rebuild
Butt you CAN'T know that until it's taken apart, and it may well be that it HAS TO BE if you need new pistons for any reason, such as, if the ones the rebuilder put in it, are the type that add the extra .020" of deck clearance to avoid problems with severely decked blocks, which DRASTICALLY lowers the compression. Virtually ALL cast pistons, MOST hypereutectics, and MANY forged (including most TRW/SpeedPro ones), are that way; and thus not suitable for a "performance" build of any sort.

I didn't know much about 355
Don't worry, that's completely OK. Aside from merely calculating the displacement from the bore and stroke, there's really nothing TO know. Whenever you see that, just think "rebuilt 350". That's all there is to it.

​​​​​​​They normally don't fit under a firebird hood without machining the top of it down or cutting the hood support out
That's not exactly true. It's primarily the throttle body that doesn't fit. Since the Stealth Ram is actually the same casting as the old "Street Ram" carb manifold that was on the market from maybe 81 or 82 up to maybe 85 (was largely a marketplace flop), which was set up with 2 little plenums on top for 2 small (like, 390 CFM) 4-bbl carbs to sit on, except w injector bungs added, it was never really intended to either fit under any hood at all, or to have its top be at an angle other than parallel to the crank. It was originally rather more of a "show" kind of thing, as opposed to a "go fast" one, until it was repurposed for EFI by adding the injector bungs and creating a different, single, horizontal-draft plenum, butt they didn't do their homework or think it all the way through very well. As a result the TB is pointed upwards whereas it needs to be pointed down. Here's you a quick trip down Memory Lane. I wish whoever took this pic had included the 2 carb plenums, butt they didn't. Oh well.



​​​​​​​I am fairly certain holley still sells stealth rams!
Well OK then. Good luck with that.
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Old Mar 19, 2025 | 08:35 AM
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Re: Cam and heads

Originally Posted by sofakingdom
Well OK then. Good luck with that.
I looked because I may be in the market.

https://www.holley.com/products/engi...ast/parts/7540
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Old Mar 19, 2025 | 08:48 AM
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Re: Cam and heads

Originally Posted by exiled350
I looked because I may be in the market.

https://www.holley.com/products/engi...ast/parts/7540
Yeah this is what I was looking at, it's advertised to fit tpi style cars early and late with the options that they have. If anyone input on this that would be great!
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Old Mar 19, 2025 | 08:59 AM
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Re: Cam and heads

Originally Posted by sofakingdom
No, the cast number DIDN'T "got milled off" unless some bozo was REALLY TRYING HARD to cheat you. The STAMPING, that encodes the application and VIN of the vehicle the block originally came in may have, but not the CASTING number. Here's what it looks like. It's located in the most convenient possible spot on the block, conspicuously right out in the open and easy to read. [/sarcasm] Top of the bell housing flange behind the driver's side head.





Unfortunately, "believe" isn't very convincing to metal parts. In any case, more than likely, it already HAS been bored, since



Butt you CAN'T know that until it's taken apart, and it may well be that it HAS TO BE if you need new pistons for any reason, such as, if the ones the rebuilder put in it, are the type that add the extra .020" of deck clearance to avoid problems with severely decked blocks, which DRASTICALLY lowers the compression. Virtually ALL cast pistons, MOST hypereutectics, and MANY forged (including most TRW/SpeedPro ones), are that way; and thus not suitable for a "performance" build of any sort.



Don't worry, that's completely OK. Aside from merely calculating the displacement from the bore and stroke, there's really nothing TO know. Whenever you see that, just think "rebuilt 350". That's all there is to it.



That's not exactly true. It's primarily the throttle body that doesn't fit. Since the Stealth Ram is actually the same casting as the old "Street Ram" carb manifold that was on the market from maybe 81 or 82 up to maybe 85 (was largely a marketplace flop), which was set up with 2 little plenums on top for 2 small (like, 390 CFM) 4-bbl carbs to sit on, except w injector bungs added, it was never really intended to either fit under any hood at all, or to have its top be at an angle other than parallel to the crank. It was originally rather more of a "show" kind of thing, as opposed to a "go fast" one, until it was repurposed for EFI by adding the injector bungs and creating a different, single, horizontal-draft plenum, butt they didn't do their homework or think it all the way through very well. As a result the TB is pointed upwards whereas it needs to be pointed down. Here's you a quick trip down Memory Lane. I wish whoever took this pic had included the 2 carb plenums, butt they didn't. Oh well.





Well OK then. Good luck with that.
I must have misundemisunderstood where the number was, I thought it was on the passenger side at the front on that tab. Thanks for entering me know I'll go look again when I'm back at my car!
I have had most of the motor pulled apart, enough to know it has a 1 peoce rear main and 2 bolt mains. Id have to check more for what pistons are in it and such as I didn't ever look into it. I'll see what I can find. I do know my crank cast and heads at the moment. I don't know my exact compression ratio then because I don't know the pistons so that is pretty obvious but I do have like 152 to 157 psi in my cylinders so that's pretty decent. I'll see what I can find out and go from there. As always thanks for the help!
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Old Mar 19, 2025 | 09:24 AM
  #11  
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Re: Cam and heads

Why 4.10 behind a T56? First gear is usually already steep enough, and an L98 doesn't need RPM to make power.
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Old Mar 19, 2025 | 09:38 AM
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Re: Cam and heads

Originally Posted by Vader
Why 4.10 behind a T56? First gear is usually already steep enough, and an L98 doesn't need RPM to make power.
there isn't a super specific reason other than I liked it. That hasn't been set in stone either though I'm definitely not closed to suggestions. I also haven't done a ton of looking at that yet as its a plan for a couple years down the road. Are you thinking that would be to much? If so would you say keeping with 3.73 is a better option? I'd love to hear your thoughts on this!!
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Old Mar 19, 2025 | 09:56 AM
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Re: Cam and heads

Originally Posted by Lordkdog
there isn't a super specific reason other than I liked it. That hasn't been set in stone either though I'm definitely not closed to suggestions. I also haven't done a ton of looking at that yet as its a plan for a couple years down the road. Are you thinking that would be to much? If so would you say keeping with 3.73 is a better option? I'd love to hear your thoughts on this!!
I have 4.10s and a 700r4, it's a bit much. I gotta be really paying attention lest I hit the 6500 limiter before I'm ready to bang second. I can't imagine a mid L98 would like that too much. 3.55 probably the sweet spot if you're looking at 5500 peak power, 3.73 if your gonna move it up.
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Old Mar 19, 2025 | 09:57 AM
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Re: Cam and heads

I thought it was on the passenger side at the front on that tab
That's the "stamping". It's 2 lines. 1st line is the application, usually about 6 or 7 characters, tells the plant the engine was assembled in and the application it was built for (truck/car, body type, 2/4-bbl or EFI type, etc.); then the 2nd line is the last several characters of the VIN. Obviously none of that is known at the time the block is cast, so they're added at different times later on during the engine's life. Casting # is cast in at the casting foundry of course, then 1st line of stamping at the engine assy plant when it's built, and the 2nd line at the vehicle assy plant when it's dropped into a vehicle. Those are certain to be at least 2 different plants with GM vehicles, sometimes 3.

I do have like 152 to 157 psi in my cylinders so that's pretty decent
Yup, as far as a running driving engine, that's fine even though a bit on the low side, and MUCH lower than a stock L98, as long as they're all within about 10% of each other. Can't tell the compression ratio from those though; WAY too many other things affect those #s besides just the static compression.

Last edited by sofakingdom; Mar 19, 2025 at 10:02 AM.
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Old Mar 19, 2025 | 10:23 AM
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Re: Cam and heads

LOOKS LIKE YOU CAN GET ONE, TO ME.
Says it'll ship today.
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Old Mar 19, 2025 | 10:37 AM
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Re: Cam and heads

Originally Posted by exiled350
I have 4.10s and a 700r4, it's a bit much. I gotta be really paying attention lest I hit the 6500 limiter before I'm ready to bang second. I can't imagine a mid L98 would like that too much. 3.55 probably the sweet spot if you're looking at 5500 peak power, 3.73 if your gonna move it up.
I probably won't touch gears until i put the 6 speed in so I hopefully won't have to worry about that!
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Old Mar 19, 2025 | 11:10 AM
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Re: Cam and heads

Looks like those links for the HSR don't include the fuel rails and hardware.

Not that it's that hard to piece something together if there's a compatible rail available, but something to watch out for.

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Old Mar 19, 2025 | 11:15 AM
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Re: Cam and heads

LOOKS LIKE YOU CAN GET ONE, TO ME.
Says it'll ship today.
Well cool. I guess they brought it back from the dead.
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Old Mar 19, 2025 | 12:26 PM
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Re: Cam and heads

I guess. I thought for sure you were right, since they have that new SBC "short ram" or whatever they call it now. But on a whim, I looked and there it was. Huh.


Originally Posted by formularpm
Looks like those links for the HSR don't include the fuel rails and hardware.
Did an HSR ever come with all of the ancillaries? I doubt it. Those parts are all readily available.
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Old Mar 19, 2025 | 01:08 PM
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Re: Cam and heads

Yeah, mine did (rails, junk regulator, crossover, and fittings). But that was back in like 2001.

The only thing HSR-specific was the rails. I'm sure there's something else compatible with the mounting holes, but they're discontinued by Holley.

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Old Mar 19, 2025 | 01:41 PM
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Re: Cam and heads

The Holley Stealth Ram is DISCONTINUED with the exception of whatever stock Holley has on hand of the lower intake manifold, plenum, gaskets, and screws to attach the plenum to the lower intake manifold.

This it all they have left. Weiand 7540 Weiand Stealth Ram Intake - Chevy Small Block V8 They had this in conventional SBC and Vortec with different level of hardware and accessories up to full stand alone systems with wiring harnesses and Holley HP fuel management system.

It's been replaced by the Holley SBC Hi-Ram. Holley made a hood-height friendly Lo-Ram front feed variant just for us 3rd gen lovers and others with hood height restrictions.

"The 300-951, a hood-height friendly Hi-Ram variant features a “front-feed” plenum and a forward-facing throttle body flange. This beast can handle up to a 95mm LS 4-bolt throttle body, including DBW throttle bodies. It’s the ultimate upgrade, REPLACING the popular Holley/Weiand Stealth-Ram intake manifold, renowned for boosting the performance of 1985-92 GM 5.7L TPI fuel-injected engines.

Perfectly designed to fit under the OE hood of Gen 1, 2, & 3 Camaros and Firebirds, the 300-951 is your ticket to transforming your ride into a high-performance machine!"

Holley 300-951 Holley Hi-Ram Front-Feed EFI Intake Manifold Kit - Small Block Chevy


Last edited by Airwolfe; Mar 19, 2025 at 01:50 PM.
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Old Mar 19, 2025 | 03:17 PM
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Re: Cam and heads

Well this is all really good information and I appreciate the replies so far. But I'm still trying to learn how to select heads and a cam for my purposes. This is the car I'm learning with so I'm okay with making a mistake and not being prefect with it.
from the sounds of it 195 heads are a good choice for me. How do I know what to look for in a set of them. what cam should i try to pair up with this. Any information in how to learn and or suggestions for what to do will be appreciated.
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Old Mar 19, 2025 | 03:25 PM
  #23  
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Re: Cam and heads

Another thought that's been bouncing around is 383 stroker. More things have been brought to my attention and it's starting to sound like that would be a good step to take with heads and a cam for this project. I'm a bit ware of doing it myself but I'd absolutely love leaning. My next year of college i will be able to take an engine machining class. So maybe pulling this motor and doing it then would be wise. That also opens up a door of opportunity to make this project something much better. I know at the start I said I would like to avoid it but honestly now it's looking appealing. If anyone has thoughts on this I'd like to hear it, otherwise I'll keep digging on my own!!!
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Old Mar 19, 2025 | 04:22 PM
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Re: Cam and heads

If you're able to do a 383, do it. The difference in useable street torque over a 350 is well worth it. And for that, yes use 190-195 cc heads.

I had to save money and re-use my AFR 180's from my old 350, and you can tell it wants to breathe more above 4500 rpm. But I'm still very happy with the way it turned out. The last few hp at high rpm is not worth worrying about for what I do with the car.
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Old Mar 19, 2025 | 05:18 PM
  #25  
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Re: Cam and heads

Originally Posted by Lordkdog
there isn't a super specific reason other than I liked it. That hasn't been set in stone either though I'm definitely not closed to suggestions. I also haven't done a ton of looking at that yet as its a plan for a couple years down the road. Are you thinking that would be to much? If so would you say keeping with 3.73 is a better option? I'd love to hear your thoughts on this!!




I have a 350 w a t56 and 4.11 in the rear. The 4.11s is awesome w the t56 close ratio (magnum F t56) The close ratio has a higher first and obviously tighter ratios w a double overdrive. If you match the cam to that HSR and tune it properly you're totally gonna open up the upper RPM range vs the TPI. I have an edelbrock pro Flo XT and it's very similar to the HSR. The better upper rpm power w the close ratio and 4.10 will be a blast. If you want a slightly less aggressive feel or a wider ratio trans a 3.73 would be good.
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Old Mar 19, 2025 | 05:30 PM
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Re: Cam and heads

350 w a t56 and 4.11 in the rear.
I completely agree. I have a T-56 in my 83 with the original weeeeeeenie stock gears (3.73, same as lots of 60s/70s muscle cars; not the original rear, just, the original ratio) and they're just ... not enough. The T-56 I have (stock one, from about a 96 or 97 F body) has the 2.5x or 2.6x, whatever it is, "close ratio" 1st, which is about the same as the older WIDE ratio Muncie or T-10; compared to the T-5 I took out, it's like starting out in 2nd. 5th is kinda the same way; USELESS until a very high speed. I kinda think sometimes about stepping up the gears.
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Old Mar 19, 2025 | 06:26 PM
  #27  
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Re: Cam and heads

Originally Posted by ULTM8Z
If you're able to do a 383, do it. The difference in useable street torque over a 350 is well worth it. And for that, yes use 190-195 cc heads.

I had to save money and re-use my AFR 180's from my old 350, and you can tell it wants to breathe more above 4500 rpm. But I'm still very happy with the way it turned out. The last few hp at high rpm is not worth worrying about for what I do with the car.
383 with 195s and a hsr should be a great combo then. I'll start researching a good 383 kit for my car. Maybe by summer I'll be able to afford heads a kit and a cam and the hsr. I will probably be limiting the car with my 700r4 until I swap for a t56 but it should be drivable still! Thank a bunch for some input!!!
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