ZL1 #140 starting mods

[1st Gen Forever]

Andy,

I'm wondering what the results will be myself!

The Mast does see a better improvement on the intake than the exhaust for sure even though both improve going off flow numbers alone. I deliberated a lot over getting the Mast vs porting the stock LSA heads and in the end 2 reasons made me lean toward the Mast. First, I can stick my stock heads on the shelf and have something to go back to if I don't like the way this turns out. And 2nd, part of my goal is not to spin the blower too hard because even though a better heat exchanger can cool IAT2s better, the blower bearings still experience the increased heat and stress when you spin it fast so I'm going with the logic of removing as much restriction to airflow as possible from the CAI, through the throttle body, blower and into the combustion chamber to allow that blower to be as effective at lower speeds as possible.

Then obviously I've done what I can with the exhaust side (custom cam, headers) with the exception of full open exhaust. I might experiment with with different header sizes, full 3" exhaust, etc later but out of the gate I'm going 1 7/8", high flow cats, and stock the rest of the way back.

It's all theory but I'm hoping to preserve a little life out of the blower by not driving it too hard but still get good gains in rwhp. 700HP with great torque everywhere will make me happy...

BTW- Can you educate me on how your Fuel pump for the ZL1 differs from stock? I haven't solved all of my fuel needs yet...

[radz28]

Originally Posted by Andy@Livernois

Actually no, unmodified blower, and unmodified blower snout, just a 90mm TB, cai, and our stage 2 heads were the only airflow improvements



Typically a 15* head is actually better for this type of build since the rotated valve angle makes the head favor the intake port even more so then it already does. Don't get me wrong better flow is better flow, but it usually hurts the exhaust rotating the angle over, and since it's a blower it needs more help on the exhaust side then the intake anyways. Again, the intake improvement is always beneficial.

It will be interesting to see the results.

AH!... Thanks for the input. That makes sense You guys are the experts

What are your thoughts on a splayed-valve? Big blocks ran these, and seems more like it would be more in line of what valve angle fits that particular valve alignment.

Thanks Andy - it's all very interesting

Originally Posted by 1st Gen Forever

I like the discussion guys!

Rad, I'm not experienced in this like the shops that have been doing it a while but from my research, if I were looking for a stealth solution, I would do the following at a high level:
-Port the stock heads
-Port the supercharger
-Go with a mild step up in cam/springs
-Change the lower pulley only (9.55 maybe)
-Larger fuel injectors
-Better heat exchanger
-Tune

Beyond the above, leaving the stock exhaust and intake would offer the best stealth look but you'll be limiting flow. If you add exhaust and a CAI with the above you should be looking at a solid 600 to 640HP to the wheels, not spend a whole lot, (maybe $8k) and look mostly stock under the hood.

Of course - thanks for your comments and input. I think you're seeing what I'm thinking. I really only want to get to a little more than 600 RWHP, because I need to pass a sniffer, too. What you're posting is really just increasing efficiency, which is what I was thinking would be for the best for me. My exhaust would strictly be CARB-shorties (ARHs) and maybe an X-pipe, so I'm a little handicapped. I might have to cheat on my CAI though... I don't know what you're spending on porting the blower, but I was thinking that would be worth a set of GMPP CNC'd heads, and I wouldn't have to really add too much more boost. I wouldn't go much more than an LS9 cam, but I really would like to keep from digging into the short block.

I'm sorry - just split-balling and can't wait to see what you come out with. I'm really looking forward to seeing the blower, because the snout looks OUTSTANDING!!! OMG!!! Are there any identification marks or machining on the outside of the heads, like below the exhaust ports or on the front or rear? Like I mentioned - I need stealth

Thanks for all your comments

[1st Gen Forever]

The Mast heads would not be stealth. They're 3/4" taller and say MAST on the front. And for a little over 600rwhp, I think Mast heads would be wasting your money honestly. You might be able to do 600rwhp leaving the heads and cam stock if you do all the other bolt-ons (both pulleys, CAI, headers, injectors) and port the blower. But to stay stealth on the outside (stock air intake) you'll probably need to do 'something' to help make up for what the stock air intake is restricting.

[RoketRdr]

Originally Posted by 1st Gen Forever

The Mast heads would not be stealth. They're 3/4" taller and say MAST on the front. And for a little over 600rwhp, I think Mast heads would be wasting your money honestly. You might be able to do 600rwhp leaving the heads and cam stock if you do all the other bolt-ons (both pulleys, CAI, headers, injectors) and port the blower. But to stay stealth on the outside (stock air intake) you'll probably need to do 'something' to help make up for what the stock air intake is restricting.

This is what I was getting at earlier radz28. The factory LSA heads and blower can take you past 600rwhp easily. So if you were just looking for that power range there's no need to mess with em. Like Aaron said just port the blower, snout, throw your bolt-ons and a tune at it and you're good to go.

[radz28]

Originally Posted by RoketRdr

This is what I was getting at earlier radz28. The factory LSA heads and blower can take you past 600rwhp easily. So if you were just looking for that power range there's no need to mess with em. Like Aaron said just port the blower, snout, throw your bolt-ons and a tune at it and you're good to go.

Point taken Thank you

[Andy@Livernois]

Originally Posted by 1st Gen Forever

BTW- Can you educate me on how your Fuel pump for the ZL1 differs from stock? I haven't solved all of my fuel needs yet...

Our pump is a drop in unit that utilizes 2 OEM quality pumps, and a bucket designed for those pumps as opposed to an aftermarket creation. We design and manufacture it to be a true drop in solution needing no wiring changes, module, or line changes. It is the same pump we used in ours to run 9's in it.

[1st Gen Forever]

So are they just a pair of pumps that flow more than the stock ZL1 pumps? Cause the ZL1 assembly from.the factory is a dual pump setup unless I'm mistaken.

Thanks!

[Andy@Livernois]

Actually, that was a big blunder mis-print in the GMPP catalog. The ZL1 pump is just a single pump.

[1st Gen Forever]

Really?! Good to know. Now it all makes sense!

Thanks Andy!

[RoketRdr]

Originally Posted by 1st Gen Forever

Really?! Good to know. Now it all makes sense!

Thanks Andy!

ISN'T THAT THE TRUTH!!??

[1st Gen Forever]

Nick Williams 102 Throttle Body showed up today!

[MrDew]

Man those machined heads look sick. Cant wait for more information on this build!

Originally Posted by radz28

Of course - thanks for your comments and input. I think you're seeing what I'm thinking. I really only want to get to a little more than 600 RWHP, because I need to pass a sniffer, too. What you're posting is really just increasing efficiency, which is what I was thinking would be for the best for me. My exhaust would strictly be CARB-shorties (ARHs) and maybe an X-pipe, so I'm a little handicapped. I might have to cheat on my CAI though... I don't know what you're spending on porting the blower, but I was thinking that would be worth a set of GMPP CNC'd heads, and I wouldn't have to really add too much more boost. I wouldn't go much more than an LS9 cam, but I really would like to keep from digging into the short block.

I'm sorry - just split-balling and can't wait to see what you come out with. I'm really looking forward to seeing the blower, because the snout looks OUTSTANDING!!! OMG!!! Are there any identification marks or machining on the outside of the heads, like below the exhaust ports or on the front or rear? Like I mentioned - I need stealth

Originally Posted by radz28

For example - I have a power goal in mind and had been considering pulleys and a little exhaust and intake mods' for several more pounds of boost.

man radz28 i need to pick you're brain at the C5Fest. It seems You're having the same stuff in mind as i do. I keep reading all those threads in the ZL1 section and wonder "how did they do it?" or "i need that, where do i go?" and sure enough i keep reading and Radz28 asks all my questions... It's almost scary how much we think alike!

P.S. i'll be taking my ZL1 to Switzerland by the end of the year and i too need a stealthy package ! Right now i'm flirting with an ADM HP650+ package with a twist (maybe add an LS9 cam and some ported goodies). how about that?

Unfortunately it also needs to be within a reasonable buget lol

[radz28]

HOLLY CRAP!!! THAT TB IS HUGE!!!

Originally Posted by MrDew

Man those machined heads look sick. Cant wait for more information on this build!

man radz28 i need to pick you're brain at the C5Fest. It seems You're having the same stuff in mind as i do. I keep reading all those threads in the ZL1 section and wonder "how did they do it?" or "i need that, where do i go?" and sure enough i keep reading and Radz28 asks all my questions... It's almost scary how much we think alike!

P.S. i'll be taking my ZL1 to Switzerland by the end of the year and i too need a stealthy package ! Right now i'm flirting with an ADM HP650+ package with a twist (maybe add an LS9 cam and some ported goodies). how about that?

Unfortunately it also needs to be within a reasonable buget lol

Regrettably - I can't make it to 'Fest this year :( Hopefully I can make it next year though There are a lot of people I'd love to me finally.

Yeah - I full of questions There are so many options, and I'm the type that likes to maximize a combination before really getting crazy. I don't like spending money on replacing parts twice, so believe me that I'm taking notes on everyone sharing their builds.

I'm all ears (eyes) Post your build so I can track and learn

[OldScoolCamaro]

Originally Posted by 1st Gen Forever

I really like the craftsmanship in these heads!

Man....so do I, outstanding workmanship and volumetric increases. That's motorhead eye candy. Keep those shots coming as you progress if you could. Thanks!