Street Lethal

iTrader: (16)

... if you pulley up the supercharger so that boost comes in earlier, but then regulate it with a wastegate on the cold side so that it dumps the charge maintaining your desired psi target, you won't believe the difference. The power under the curve is unreal. I hear you about not wanting to grenade it, it gets very expensive. I know my 305 will blow up eventually, either that or the drivetrain will give, but I am just building it for the hell of it and to have some fun. Now she is sporting some seriously ported heads (valve guides are non existent in the bowls), although the valves are 1.84" not 1.94" like the 882 heads I ran, but she is running a 23x/23x cam, I tossed the 218/218 cam, also a T72 turbo, I sold the T76, all controlled by Rauscher's EBL-P4. I got some good runs with some very good competition coming up. Here is my latest vid, just making some final adjustments and she is good to go.

91 rally sport

iTrader: (2)

If I choose to go turbo(s) after a while the ebl -p4 will let me tune to that right?

1991sleeper

iTrader: (-3)

Yes

Orr89RocZ

iTrader: (20)

You cant compare gn v6 head valve sizes to sbc standard head sizes. Valve angles are entirely different animals and flow characteristics completely different. Thats why they make power. 1.9 valve at 10-15 deg angle is more like a sbc 2.125 valve in a 23 deg head. Conventional small block needs much more head size to make air flow thru the port to fill cylinder the same. Ls1 same way. Stock head may only flow 240-250 cfm on bench but in real life they make as much if not more power than 195cc afr sbc heads flowing 280

91 rally sport

iTrader: (2)

Ok. So xfi 268 cam. Trick flow super 23 heads. What valves, springs, and other valve train parts should I be using?

91 rally sport

iTrader: (2)

before I buy the wrong thing. its the ebl-p4. not the plain ebl right

Street Lethal

iTrader: (16)

Fortunately I can in fact compare them, because for one, I port both SBC and standard production Buick V6 heads for good friends of mine, and two, flow characteristics mean absolutely nothing when it comes to boost because there are two sides to the spectrum. Let me explain something, good cfm in the heads means less boost resistance pressure to attain desired horsepower levels. Poor cfm in the heads means increased boost pressure utilizing a turbo that flows more cfm to attain the same desired horsepower. It is either of the two, or a combination of both if that is one's goal. The only time valve angles serve a purpose is when we run naturally aspirated, and natural aspiration is a thing of the past. Let's delve into this a little further, how much more flow do your cylinder heads flow for your big cubed V8 engine running x amount of boost compared to a lightly ported set of GN heads on a semi worked 231 GN engine? Can your larger valve sizes and better valve angles explain why a set of bone stock GN heads with a little cleaning up behind the valves run just as fast as your setup with a single turbo in comparison with your twins at boost levels equivalent with yours...?

I can show you, not hearsay, but show you a V6 cylinder head that flows much much less than yours with its poor design, yet run just as fast as yours running an equivalent amount of boost pressure when you calculate engine size vs cfm, not to mention the same calculation using one single turbo vs a set of twins which you would have the advantage of at lower boost pressure levels, and all this at 3400 - 3500 pounds of vehicle weight, so kindly, and I emphasize kindly, refrain from telling me what I can and cannot compare, and what does and does not work, because this is all we do at the track, test, test, and test. Stock set of GN castings are absolute garbage with tiny little valves, yet with some slight cleanup behind the valves, not even touching the ports, they have been mid to high nines right in front of me, and low to mid nines as per some of the members of the Buick boards. Port them and members have been deep in the 8's, and these are with moderate boost levels, nothing above 30-psi. You think it will take cfm and valve angles in the heads to run faster? You think they have nothing left after that? There's plenty left after that, and it isn't a matter of how much flow the heads have when they want to go faster because that is never as issue, its more of an issue of how much more will the block take.

Turning thread after thread into some dyno number pissing match to justify such numbers because you chose to go with big cubes and better cylinder heads is a senseless argument on your part because the fact is, ANY engine will flow whatever you want it to because boost pressure is unlimited, and stock parts can be ported to always allow for more power at lower boost pressures. There is a point in which we exceed the necessity for single digit potential, and from there the point soon becomes redundant. This is exactly why most members on this board with their "350 V8's" get spanked on the street by four and six cylinder vehicles, because their focus is somewhere it really shouldn't be because you have senior members still bent on cubic inches and preaching old adages. But getting back to the conversation, the stock GN head below can be bought for fifty bucks as a pair in the junkyard, and has been deep in the nines on a pushrod 231 V6 with a much smaller cam, tiny set of valves and horrific valve angles a la 80's technology. Open them up and you will go as fast as you want to because it is a matter of boost pressure and turbo cfm, not so much cylinder head cfm, because again, both play a part in how much boost pressure will be needed, and boost pressure is infinite. How much did you pay for your heads to run similar numbers with all of the bells and whistles for a much larger engine, and was it really worth it? It really wasn't, but because you did go that route, you continually try to defend such a decision by playing the dyno graph game. NA aftermarket parts designed to increase air intake are a joke, whether cylinder heads, intakes or Granatelli MAF's, I don't waste my time with them...

Stock GN head which has been well into the nines for fifty bucks...



Ported GN head which has been well into the eights with some porting time...



Again, how much did you pay for yours to run the same numbers?

Street Lethal

iTrader: (16)

EBL-P4 for TPI w/Speed Density (90-92) harness...

PM RBob, he is the firmware writer, and one hell of a nice guy...

Orr89RocZ

iTrader: (20)

I still think you are out in left field with this. Flow does matter in boost because notjin changes. physics of air flow remain same regardless of the gas density. The pressure ratios across the valve are similar ratios to na just they are at a higher static pressure. Talk to any head guru, and they will say you dont need to do anything different to a turbo head than what you would do in a na motor except maybe inconel exhaust valves for endurance apps.
And second, my car hasnt ran at the current power level so how do you know anything about what a v6 does compared to mine? Only thing i got right now is a dyno figure. Show me one making 1000 thru a th400 on pump gas No meth No race gas no E85 show me a low 8 sec buick on pump gas thats over 3650 lbs.


You know why that is?? Valve angle!!! Flow numbers mean **** on the bench! And no twins doesnt mean any advantage over a proper single. Esp not at lower pressures because my housings are huge for low pressure performance.

Look i never had a problem with you and enjoy your posts and input from time to time but you are delusional!! Clearly butthurt because i never mention anything about my dyno numbers until two seconds ago in the paragraph above this one. Where have i ever turned threads into pissin matches over my dyno numbers??? What numbers are you refering to? my 9 second pass??? that was with afr 195 and baby cam. no high dollar setup. And that wasnt even maxed out, i left like a school bus. Yet you want to start attacking me because i corrected your flow theory by stacking me up against race buicks with my street car.
My build had a target goal change over the years and this last setup was expected to make big numbers on lower boost and pump gas alone. If you think it was a waste show me another guy with a small motor making similar numbers using basic hyd roller cam and pure pump gas. Not many can. And you think the heads dont matter...
If anything, you are the one preaching all this turbo stuff to stock motors with nothing to back up your claims. 3-4 year thread on a 9 sec 305? All you do is reference buicks and they arent even in the same ball park. Atleast i have results...

Sure stockish parts can take 100 psi of boost to make big numbers but that dont run on 93. That aint easy to keep charge temps cool. The build is a system, you gotta look at all angles. Doing it over again i mentioned i would have done things alittle different.