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For that price, id rather see you go with the scoggin dickey heads. Their refurbished/modified GM heads vs the china crap summit makes. I dont think youll have a problem getting to the 500 mark with a procharger. My car with a small 212/222 435/460 lift flat tappet cam, vortec heads, and 5 lbs did 351, so i dont think youll have a problem getting to 500. Only question is what do those heads have for springs? You may need to upgrade them
It says 0.520 max lift I can just get new springs for them and 1.6 rockers and how is vortec heads with hsr?
Yeah but what about spring pressure. My stock vortec's were only 80 lbs seated. Max lift may not be because of just coil bind. Retainer to valve stem seal clearance and valve stem length is also the other lift limiting factors. Comp has retainers that can give you another hundreths of a inch, but if you swap retainers you might need to switch springs, and if you switch springs they may be too large for the spring seat and need to be machined.
i loved my vortec's and HSR. i only went BPE 195's because the cost of larger valves, screw in studs and spring seat machining was almost more than new aluminum heads. I got alot of torque and throttle response out of that setup. With that intake/head/cam combo it dyno'd 377 ft lbs almost all the way across the graph. Torque was everywhere
Last edited by 86CamaroDan; 12-11-2017 at 08:54 AM.
I have looked at those scoggin dickey heads, and I found different heads and i might just say screw the 383 and go 355 https://www.summitracing.com/parts/hpe-sbc64195 or https://www.summitracing.com/parts/hpe-sbc64185 what do you think?
Last edited by SketchyZed; 12-11-2017 at 10:38 AM.
At 300 Hp naturally aspirated you are talking about adding 66% more power (200 Hp) via supercharger. That's a ton. I would build the engine with a stronger power curve naturally aspirated and rely less on the supercharger to make up the difference. Engines with mild boost live a longer life, make more consistent power, and won't overheat nearly as quickly when pushed hard.
At 300 Hp naturally aspirated you are talking about adding 66% more power (200 Hp) via supercharger. That's a ton. I would build the engine with a stronger power curve naturally aspirated and rely less on the supercharger to make up the difference. Engines with mild boost live a longer life, make more consistent power, and won't overheat nearly as quickly when pushed hard.
My old late 90's 355 made over 560hp with a vortech S-trim, no intercooler.
im not trying to put lots of boost in it im thinking just 8psi i'm just having a hard time finding heads and if i do find heads i want to make sure they work well, i know if i build a 355 my intake volume should be 185cc at least and the intake i want the hsr should open up more in the high rpm range and i would prefer 400hp then boost it
im not trying to put lots of boost in it im thinking just 8psi i'm just having a hard time finding heads and if i do find heads i want to make sure they work well, i know if i build a 355 my intake volume should be 185cc at least and the intake i want the hsr should open up more in the high rpm range and i would prefer 400hp then boost it
8psi is kinda meaningless. I look at it as flow, based on pulley combination. The same blower and pulley's might make 8psi on my motor and 26 psi on yours. Boost pressure doesn't tell me anything about power.
This stuff is a little more difficult to figure when you are using turbos because who knows what RPM the turbo is at at any given point in the powerband.
8psi is kinda meaningless. I look at it as flow, based on pulley combination. The same blower and pulley's might make 8psi on my motor and 26 psi on yours. Boost pressure doesn't tell me anything about power.
-- Joe
I wouldnt say its meaningless. I think its more of a measure of stress on the internals. All boost is, is a measure of resistance, so i do agree with you on that. Every engine breathes differently.
Im looking at compression ratios again to get this prefect heads i found three i could use but i just need to find a safe compression for boost
Go 9-9.5:1 with alum heads
And whats your budget? Heads are everywhere for sbc. From stock vortecs in iron to aluminum budget stuff like flotek/proheader to higher end afr/trickflow/profiler/dart etc
A d1 procharger will easily do 500 hp on that with mild boost. You dont want alot of blower rpm if you dont need it. Small pulley means more chance of belt slip. And more stress on front crank snout and main bearing
8psi is kinda meaningless. I look at it as flow, based on pulley combination. The same blower and pulley's might make 8psi on my motor and 26 psi on yours. Boost pressure doesn't tell me anything about power.
This stuff is a little more difficult to figure when you are using turbos because who knows what RPM the turbo is at at any given point in the powerband.
-- Joe
I hate blowers because they give a max cfm which is meaningless. You cant use it for anything. They should give a map like a turbo because it is a compressor wheel just like a turbo. You'll then know what pressure ratio it makes and what mass flow it flows to figure what power you can make with it on your engine
From turbo map, you still know what rpm the shaft is spinning roughly by the pressure ratio and power your motor makes. Its not exact cuz its math using estimates for some things but you do have an idea.
It took me all day to figure this all out but I got three build sheet just bolt ons from the 350 I have now if I plan on going to 355 I can use the same heads I just need to get a rotating assembly and for the 383 I just need better heads which I found and the rotating assembly and I've gone through a compression calculator found everything I needed and I should all be between 9 to 9.5 compression ratio, so they should be safe for Boost
As for budget first without the supercharger I just plan on heads Cam and intake and that's it for a while so it would be the HSR with all it needs the heads and the cam and before I do all that I'm going to rebuild the trans get a better ECM that I can tune and 3.42 gears and better tires and wheels so I'm gonna guess with all that togeher let' just say 3500$ for now I'm gonna do all these in steps and prioritize from most important to least important at the moment
Last edited by SketchyZed; 12-12-2017 at 11:18 PM.
Theres alot of good heads under 1300$ for either 355/383. Could use same head for each. Dart shp, profiler, speier's flotek castings, proheader. They are decent heads for around 1100-1200$. Whatever you do put in quality springs
I hate blowers because they give a max cfm which is meaningless.
It allows you to calculate max HP potential of the head unit in it's efficient area. It's part of blueprinting.
Originally Posted by Orr89RocZ
You cant use it for anything. They should give a map like a turbo because it is a compressor wheel just like a turbo. You'll then know what pressure ratio it makes and what mass flow it flows to figure what power you can make with it on your engine
Here is the compressor map, provided by the manufacturer, for my t-trim:
My blower is setup at 48,000 RPM at MAX rpm, which is a little over 80lbs/minute air flow. (or about 1200 cfm). If that translates to around 14-16lbs of boost it should be right around 70% efficient.
Not bad for a street car. Not nearly as impressive as your 2500hp twin turbo big block, but for something that idles well and starts in cold weather I'm happy with it.
Originally Posted by Orr89RocZ
From turbo map, you still know what rpm the shaft is spinning roughly by the pressure ratio and power your motor makes. Its not exact cuz its math using estimates for some things but you do have an idea.
Right, I totally agree. Once your combo is on the dyno, and you know the power it's making, and the boost pressure you will know your impeller speed based on the compressor map.
This must be why it feels like guys on this forum swap their turbos more often than I swap girlfriends..?
oh okay and the 383 heads are the same thing just with 64cc and 195cc Intake Runner
The heads will all bolt up and work. Ya just pick the head size (valves, runners, combustion chamber) based on what kind of air flow the engine needs. Like I mentioned in the other thread we were discussing. I chose a relatively small 180cc head for my 383 because it's a TPI. The TPI promotes velocity over volume, so I chose a head that on a 383 would do the same. Torque torque torque....and it's all over by 5200 RPM!!! -but what a ride!
-your needs will be grossly different!!!!! ...I have not been following super close, as supercharging is certainly out of my element, but I'd imagine a 195cc head would be well suited for a HSR 383, generally speaking.
Well before I even begin to make my car faster I need to focus on a rear main seal leak and an intake leak but after that I will be saving up for my mods
My HSR will pull to 6000RPM no problem, maybe even 6500, so i dont think flow is gonna be a issue. Most people choose a 195 head to keep the low end power there while providing sufficient top end. Might be able to do a 200/210 but your low end will suffer.
My HSR will pull to 6000RPM no problem, maybe even 6500, so i dont think flow is gonna be a issue. Most people choose a 195 head to keep the low end power there while providing sufficient top end. Might be able to do a 200/210 but your low end will suffer.
210 will be a problem with the HSR. I had to weld material to mine to cover the large 1206 ports adequately.
I think the OP should just do heads, cam, intake and blower. The whole 383 thing is a waste of money.
The heads and intake i can get ported for more flow
500hp is all i want do you think these heads cam and intake would get me there
You're wasting your time converting to a 383 if you're only targeting 500-HP w/boost, your 350 will make that without even breaking a sweat running a supercharger. In my opinion you're going well out of your way even contemplating additional port work on top of a set of aftermarket heads. Even the guys over at Motor Trend got some pretty big horsepower numbers with a 350-SBC, 195 heads and running a Procharger at a moderate amount of boost pressure. Their final numbers peaked at 25-psi of boost pressure, but that was because of the limitation of that camshaft and their timing numbers.
have a cog drive V1 T trim with everything. polished head unit. for the 88/92 Camaros (and install book)
$2800 + the ride..best deal in town...cogs the way to go..even a few other parts(coolers) just sitting...not going to use it...as I'm going big block 615cid..
Last edited by articwhiteZ; 12-15-2017 at 08:34 PM.
have a cog drive V1 T trim with everything. polished head unit. for the 88/92 Camaros (and install book)
$2800 + the ride..best deal in town...cogs the way to go..even a few other parts(coolers) just sitting...not going to use it...as I'm going big block 615cid..
The stealth ram could work as spoken about here. The port corners get thin. It has height just not the corners on older manifolds. The casting change supposedly added material around the corners. To bad the pics dont work
The stealth ram could work as spoken about here. The port corners get thin. It has height just not the corners on older manifolds. The casting change supposedly added material around the corners. To bad the pics dont work
Y'all think i should just port stock tpi and go from there since im boosting it?
If you have access to and feel comfortable welding aluminum you can make those TPIs flow more pretty cheap. You really just need a few pieces of aluminum plate and an AC/DC Tig rig for the runners, port and polish the plenum and ether get a new base or port the stock one.
There's plenty of videos and threads demonstrating how to port and polish and modify a TPI
Going all the way back to the other thread where we were discussing your set up..... I still think you're getting caught up making a best of both worlds engine, both N/A and supercharged. How long will it be naturally aspirated? -because that's how long you'll regret NOT going HSR. Why would you keep the TPI? Especially on top of some high flow 185cc heads??? Forgetting the time and patience needed to port the TPI properly, it still won't perform like an HSR.
...unless of course you've given up your goal of 350-450 n/a HP, and are going budget build until you can afford the blower.(I'm a fan of this) -Then I'm completely on board with keeping the TPI.
This made almost 600hp, and is completely streetable:
It's a cheap combo, Holley singleplane intake and 4bbl throttle body with turbonetics lid. Fits under a stock trans-am hood.
.040 over block, 195cc aluminum heads (240cfm), 224/230 cam, 9.5:1 compression. You could easily make 500+ with your stock L98 with a cam swap, heads, and intake and S-trim blower.
First cam is too small. If your not doing forged pistons for a rotating assembly, i wouldn't bother. If you've got the time, id take yours apart, throw some new rings in it and make sure their properly gapped.
Agreed. I wouldnt use a cast eagle crank. If you stay 355, use stock crank imo. If you want a 383 get a forged steel crank. Also would do forged pistons for best reliability and safety during tuning. BUT a hyper piston will work fine when set up right for proper clearance and ring gap.
Cam could be 1-2 sizes larger as well
Why are you even digging into the short block? Why not save all the machine work for if you decide to go 383 down the road. 5 cubes isnt gonna make much of a difference. I say run a stock bottom end, but gap the rings. Building the bottom end twice seems like a waste of time and money
Last edited by 86CamaroDan; 12-22-2017 at 10:59 AM.
Why are you even digging into the short block? Why not save all the machine work for if you decide to go 383 down the road. 5 cubes isnt gonna make much of a difference. I say run a stock bottom end, but gap the rings. Building the bottom end twice seems like a waste of time and money
I agree. I'd do heads, cam, intake, blower. Why mess with the bottom end.
If it blows up, buy a real block and build a nice motor.
Although, I dunno if I'd do a 383. I'd probably do a 350/355 with 6" rods, and only a 355 if I needed to bore it to fix cylinder damage.
Then again, I've got boxes of rods and pistons in my basement and I think they are all .030 and .040 over forgings so I'd probably use those lol.
How many guys on here have broken cranks at 500-600 hp? I ran a blown motor for years on a cast crank, "x" rods, and forged pistons and never walked over the crank. I've always used forged cranks since, but not because I actually broke one, but because cast cranks suddenly cost the same.
I have a bunch of GMPP cranks in the shop, cast. It costs me more to have them turned and polished, radiused, etc than it does to buy a forged crank now
I gave you a video showing you what you need to do. People still seem to get caught up with heads and cam when it comes to boost. If you are that worried about heads and cam with a 350 engine, then why not just shoot for 500 horsepower with a naturally aspirated engine? With boost it is just a matter of how much you need to get to that number, and you don't want increased compression or grand valve events. If you're planning on putting that much thought into the engine then wasting money on a blower, it is absolutely pointless. You can build a healthy 350 with heads and cam and spray it with a seventy five to a one hundred shot to meet your 500 horsepower goal and save loads of money. If you're planning on boosting it with a blower, then you should be shooting for way under 300 horsepower with low compression and plenty of vacuum at idle, with about ten to fifteen pounds of boost to reach your goal. Otherwise why even bother wasting the money on a blower if you want the naturally aspirated side of the engine to do 75% of the work lol? Boost will get you where you want to go, there is no reason to overthink the engine. Factory Grand National engines are cast on the bottom end and need to burn more fuel per cylinder to match your V8, and people throw 30-psi at them running pump gas w/methanol, and 500 horsepower is a walk in the park for them with small valves, and I mean small. Stop overthinking it. Shoot for low compression, smooth as silk idle, and run as much boost as you need to to reach your goals. Why waste thousands of dollars on a blower to run only 5-8psi of boost pressure on top of a modded engine? I mean seriously, for that kind of money, let the blower do all the work for you via boost pressure, that's what it's there for...
I gave you a video showing you what you need to do. People still seem to get caught up with heads and cam when it comes to boost. If you are that worried about heads and cam with a 350 engine, then why not just shoot for 500 horsepower with a naturally aspirated engine? With boost it is just a matter of how much you need to get to that number, and you don't want increased compression or grand valve events. If you're planning on putting that much thought into the engine then wasting money on a blower, it is absolutely pointless. You can build a healthy 350 with heads and cam and spray it with a seventy five to a one hundred shot to meet your 500 horsepower goal and save loads of money. If you're planning on boosting it with a blower, then you should be shooting for way under 300 horsepower with low compression and plenty of vacuum at idle, with about ten to fifteen pounds of boost to reach your goal. Otherwise why even bother wasting the money on a blower if you want the naturally aspirated side of the engine to do 75% of the work lol? Boost will get you where you want to go, there is no reason to overthink the engine. Factory Grand National engines are cast on the bottom end and need to burn more fuel per cylinder to match your V8, and people throw 30-psi at them running pump gas w/methanol, and 500 horsepower is a walk in the park for them with small valves, and I mean small. Stop overthinking it. Shoot for low compression, smooth as silk idle, and run as much boost as you need to to reach your goals. Why waste thousands of dollars on a blower to run only 5-8psi of boost pressure on top of a modded engine? I mean seriously, for that kind of money, let the blower do all the work for you via boost pressure, that's what it's there for...
- Rob
A 500hp n/a motor usually runs like a turd, with a nasty cam.
Probably "cool!" for a lot of members here, but honestly would you want to drive something that sounded like a '72 chopper every day?
I like the idea of free flowing heads with a small cross section, moderate cam with great idle, no lope, and a lot of boost.
I've thought about parting out my 412 several times and replacing it with an LT1. I have two on stands with bags on them in the shop lol. The only issue is the compression ratio is too high on those things.
A 500hp n/a motor usually runs like a turd, with a nasty cam.
The point I'm trying to make for him is that he is bent on this 500 horsepower kick, and he is putting way too much thought into the engine itself while planning on running a blower. A stock set of heads, although aren't necessarily ideal, will in fact flow what he needs in conjunction with the blower to meet his goal. He doesn't need aftermarket heads, or some glorious camshaft to make it all work for him. A good cam and ported iron heads will work just fine. Truth be told that he could invest mucho dinero in aftermarket heads, aftermarket cam and Procharger blower, and yet I'll bet ya I can make the same, if not more power slapping a turbo onto my 2.8 Firebird. In fact I know I will.
Zed, My car last year did 351RWHP through stock vortec's(Stock GM350HO at that), a 212/222 435/460 lift flat tappet cam and 5 lbs of boost and no intercooler(and missing alot of timing off my ignition map that i wasnt aware of). Im assuming my setup bellow should do 450-500 @ 7lbs and no intercooler. completely 100% stock bottom end with well over 50K hard miles on it. You dont need a built bottom end, not yet anyway.
Last edited by 86CamaroDan; 12-22-2017 at 01:11 PM.
Why yes a all motor with 11:1 compression making 500 or more to the wheels plus nos is cool that's not what I want to do, I want a nice streatable car that i can take to the drag strip swap some drag tires make a few passes the change them back and drive home. 500hp is all I want and all I would ever need and those heads I want are lighter
12-10-2017, 06:51 PM
...I have not been following super close, as supercharging is certainly out of my element, but I'd imagine a 195cc head would be well suited for a HSR 383, generally speaking. 
