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TBI 350 Power Upgrades

aglinks said:
I don't know if this is beneficial, but I just checked the VIN and it is a K code engine.
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Buddies L05 as of today looks like it's on it's way out, can't find much about any potential diffrerences, but I notice there were 2 and 4 bolt L05 crate engine replacements GM sold, but the 4 bolt is discontinued.

No idea what VIN code his is, but my guess is that is related to emissions/GVWR, since the 2/4 bolt difference was based on GVWR apparently.
 
Seems as though all you guys know best here.. if you want a ride in that megasquirt tbi truck @aglinks and your in ca lemme know.. I'll show you real world gains.. not this internet babble..
 
sreidmx said:
Seems as though all you guys know best here.. if you want a ride in that megasquirt tbi truck @aglinks and your in ca lemme know.. I'll show you real world gains.. not this internet babble..
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Kind of confused, not sure anyone has tried to attack anyone else's knowledge here. If we knew exactly what was best, our engines would be in all sorts of championship winning cars, not sure any of us can claim that.

No reason people can't have a discussion about making power, with different theories how to get there.

I also have no problem giving anyone a ride in my rig. I'd have fun running against a stout L05...manual trans, 3.42's and all. :)
 
dyeager535 said:
Kind of confused, not sure anyone has tried to attack anyone else's knowledge here. If we knew exactly what was best, our engines would be in all sorts of championship winning cars, not sure any of us can claim that.

No reason people can't have a discussion about making power, with different theories how to get there.

I also have no problem giving anyone a ride in my rig. I'd have fun running against a stout L05...manual trans, 3.42's and all. :)
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Don't think Reid pointed that at you. But he is a turd
 
1-ton said:
The cam I bought for my TBI engine is a COMP Cam/Computer Control cam. It has close to 30 degrees more duration, and about 20 thousands of an inch more lift than the stock cam. The cam is a single pattern cam, in order to keep down the vacuum fluctuation. Because of the single pattern, the cam is able to get away with 111 degrees of LSA, in order to give it more low end. I did not want to go crazy with a cam that had more lift because my stock swirl-port heads have press in rocker studs. If you go with a cam that has any bigger specs than mine, then you definitely need to go to a wider 112 LSA or more.

My GM Goodwrench TBI engine came with about 9:1 compression 64 CC heads. Different web sites listed different specs on compression for my engine, but it is safe to say that it is at least 9:1. Edelbrock makes a set of Swirl-Port aluminum 64 CC replacement heads that have bigger valves and slightly smaller ramp that give the intake runners a few more CC's of flow.
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Do you happen to have a part number for your cam? Also, did you get a different chip for the computer to run that setup?
 
If I was running TBI, based on the cost, I'd probably look at some of the carbureted intakes with an adapter as well. Last I looked, TBI specific intakes were few and far between, with prices to match. But, I'm not running TBI, and I haven't done any research on them. I don't know how "bad" the stock TBI intake is, and I'd certainly do a bunch of reading on it before I started considering moving away from the stock one. And if I went that route, I'd probably resign myself to changing everything else to match. My decision was easy...there was one intake for TPI and Vortec heads.

My focus (with great internal difficulty) has been away from thinking bigger is better, and being realistic about how I use my truck, and what I need the engine to do for me. Transmission, gearing, tires, trailering, all point to low end torque requirements *in my situation*. Outside of exhaust manifolds, I'm not sure GM left a whole bunch on the table based on what they were dealing with in the L05. Compression is decent, the heads actually aren't terrible for a truck, the power is at a useful RPM, etc.

The L05/L98 engines of that vintage IMO are when GM started to pull their heads out. You can tell there was actual effort put into the engines making power again. EFI had a bunch to do with that, by more easily meeting emissions standards, but I hesitate to second guess a whole lot of what they did with those engines. Working within the confines they had (gen 1 blocks old chamber design) when compared fairly, the Vortec 5.7 was not a huge accomplishment over the L05. To really make more power with TBI, it looks to me like you've basically got to remove everything specific to the L05, and replace it, which is pretty much what GM did with the L31.
 
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aglinks said:
Wouldn't the added lift from a different cam improve flow through the heads?
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the problem is maximum flow once the flow starts being impeded by the design, you won't get more air and fuel in - no matter the duration. Something to consider - when a valve opens two things get the fuel and air into the cylinder - first is the drawing by the piston, but more importantly is the air/fuel mixture stacks up above the valve when it closes. Just as if you slam the door in the face of your brother and he can't stop fast enough - that momentum creates pressure (and the really clever folks use that wave that bounces between the valve and the butterflies) that, when the door opens again the brother... errr... fuel and air comes crashing in.. The problem as this example illustrates is when your brother trips and crashes up against the door his force in thrown into the floor and doesn't allow him to rush into the room. *no brothers were hurt in this example*
 
sreidmx said:
It allows the air a longer duration to enter the chamber, which if your exhaust is setup to scavenge will become part of the equation on the exhaust stroke if there is overlap in the intake and exhaust events.


That ramp was gm's attempt to swirl the fuel and air mixture. I don't know what physics @superbuickguy is subscribing too but I fail to see how increasing duration and adding some much needed lift to an air pump is going to be less of a gain? We're not applying a camshaft profile so big here that it creates less intake vacuum and makes the low end laggy..
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just go with the flow.... you'll swirl in :D

the tl;dr is if the heads choke flow then no amount of lift or duration will get more air and fuel into the chamber (leaving the discussion of wave and reversion for a later)

real world example. I'm building a BBC 427 with 350 cfm flowing heads. A friend is building a SBC 427 with 205 cfm heads. projected hp of either is 700 for the bbc to 500 for the sbc. Flow is everything.
 
superbuickguy said:
just go with the flow.... you'll swirl in :D

the tl;dr is if the heads choke flow then no amount of lift or duration will get more air and fuel into the chamber (leaving the discussion of wave and reversion for a later)

real world example. I'm building a BBC 427 with 350 cfm flowing heads. A friend is building a SBC 427 with 205 cfm heads. projected hp of either is 700 for the bbc to 500 for the sbc. Flow is everything.
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Flow is nothing without the cam. Haha put the 167 duration cam in that sbc or the BBC and see how much power it makes. They are inner related so you can have one without the other, regardless, the power level we're talking about does not exceed the flow potential of the stock head.
 
sreidmx said:
Flow is nothing without the cam. Haha put the 167 duration cam in that sbc or the BBC and see how much power it makes. They are inner related so you can have one without the other, regardless, the power level we're talking about does not exceed the flow potential of the stock head.
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but cam is nothing if the heads won't support the flow. worse, if the cam is too large for the heads, it will run worse then it did with that stock cam. Flow on ramp heads - max, mind you, is something in the neighborhood of 135 cfm at max lift.... with a mild cam, 2 barrel tbi, and cast iron exhaust manifolds it is enough - but the moment you start doing anything to upset the cart, it's a waste of money.... conversely, if you leave the cam, leave the intake, leave the exhaust manifolds - you will get 50 plus hp by swapping to Vortec. Then change the cam, add headers, and put a BB TBI on it.... easy 125 net gain.

start with the heads.

and before you start about bolt pattern - you have 2 choices, either patriot heads that mimic the vortec chamber or vortec heads and redrill the holes... yeah, I know, the magazines get all snotty about it - funny thing the engine couldn't care less.

just as an aside, I've got a flow file that was done on both the vortec and the ramp heads because my wife needed them... and she used the theory behind those heads to create an inhaler for asthma patients that doesn't require an aerosol - to say I've way too much time in these designs would be an understatement.....

and I forgot about this - there was a year or so when the ramp heads were the latest thing for modifieds. If you ground the ramp out, the heads actually flowed really, really well.... just you had to grind the ramp out. The next year they allowed Vortecs and the ramps were relegated to the scrap heap.
 
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superbuickguy said:
but cam is nothing if the heads won't support the flow. worse, if the cam is too large for the heads, it will run worse then it did with that stock cam. Flow on ramp heads - max, mind you, is something in the neighborhood of 135 cfm at max lift.... with a mild cam, 2 barrel tbi, and cast iron exhaust manifolds it is enough - but the moment you start doing anything to upset the cart, it's a waste of money.... conversely, if you leave the cam, leave the intake, leave the exhaust manifolds - you will get 50 plus hp by swapping to Vortec. Then change the cam, add headers, and put a BB TBI on it.... easy 125 net gain.

start with the heads.

and before you start about bolt pattern - you have 2 choices, either patriot heads that mimic the vortec chamber or vortec heads and redrill the holes... yeah, I know, the magazines get all snotty about it - funny thing the engine couldn't care less.

just as an aside, I've got a flow file that was done on both the vortec and the ramp heads because my wife needed them... and she used the theory behind those heads to create an inhaler for asthma patients that doesn't require an aerosol - to say I've way too much time in these designs would be an understatement.....

and I forgot about this - there was a year or so when the ramp heads were the latest thing for modifieds. If you ground the ramp out, the heads actually flowed really, really well.... just you had to grind the ramp out. The next year they allowed Vortecs and the ramps were relegated to the scrap heap.
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It's not going to gain 50 hp just switching to Vortec heads from the late model TBI heads. Stop this nonsense. This has been debated over and over on here.
Go find it
 
superbuickguy said:
funny you mention that.... it's probably more


now don't ever argue with me again.
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Yeah we saw how that works. You get all but hurt when you're wrong.

Too bad you didn't leave when the mods called you on your BS your first week

Go away Noob
 
I was right then, and now. I have the very motor in my FJ40... but then again, I'm sure when the chevy small block came out, you were sure it just wasn't possible that the sbc made 200 hp. Then suddenly the LS came out and the science of motor building really came into its own - but you just can't believe it.

compression plus flow equals power. Yet you still don't believe... represent all that's wrong with hot rodding because you don't believe even with countless dyno sheets.

go back to pirate, they'll love you there.
 
I appreciate people who want to play the fool. I provide numbers, part numbers, dyno results and even personal experience - after all, the FJ40 has a 93 bottom end with Vortec heads and TBI - The other side always plays with personal attack, bluster and "brotherhood"

The deal is I've been suckered in by their crap before - and quite frankly, playing them as fools does a great deal towards healing from the bs they've inflicted on me in the past... worst of the bunch was this one. I had an 83 Chevy pickup (this is mid-90s) where it was beat into my head that I needed a "torque" cam .... no one ever asked the compression, what it was going in, just it had to be a "torque" cam. It was the most disappointing motor I've ever had - I know what was wrong now, the heads.... 2.02 heads with 10.5 compression pistons made it rattle like there was no tomorrow. The only way to make it run on the street was a holley 650 double pumper and make it run pig rich with timing that, all in, was in the 28 degree range.

To anyone - whenever someone is telling you what to do, make them prove it. Make me prove it. part numbers, dyno results, theory behind their numbers, hell even fluid flow results.... but never, ever listen to the brotherhood when they say "it won't work" and never prove up what they say.... and if you still don't believe it - we can dyno it.... of course, if they won't believe engine masters, then they certainly won't believe a dyno in Seattle either....
 
Wow... really...
I was the one to post the flow numbers of these heads, everyone already knows what vortecs do, you for some reason feel the need to perpetually argue that you can swap the heads and do nothing else and make 50hp, the rest of us are trying to work around the budget and stick with the oem head, under the horsepower threshold the op is wanting all his goals are totally achievable with oem stock heads.. why you feel the need to ram this other position home is beyond me..
 
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