Should I listen to Sean

[BADDASSC6]

I was considering a Magna charger 122, but Sean suggested building a 402 screamer. I have been debating it ever since. I pretty much decided that upgrading to a z06 would be out of hte question. My car is almost paid off and I don't want to make payments for an extra year or two for a used Z06.

Pros and cons of each:

402
1) 402 from A&A goes for $4k comes with a New CAM and has forged internals. I can probably get this for $6K installed.
2) I have EPT 205 heads most cars with 402 run AFR 225 heads. I think my heads might limit the power up top.
3) My fast manifold already has nitrous bungs. Forged internals means I can spray a huge shot (200).
4) 480-490 rwhp max without spray.

Maggie
1) 122 Maggie $6K plus new hood $1.5K.
2) 550 rwhp on stock LS2s with exhaust only.
3) No nitrous bottle to refill.
4) How close am I to the LS2 limit:sm_up_there:

[94cobra69ss396]

I was considering a Magna charger 122, but Sean suggested building a 402 screamer. I have been debating it ever since. I pretty much decided that upgrading to a z06 would be out of hte question. My car is almost paid off and I don't want to make payments for an extra year or two for a used Z06.

Pros and cons of each:

402
1) 402 from A&A goes for $4k comes with a New CAM and has forged internals. I can probably get this for $6K installed.
2) I have EPT 205 heads most cars with 402 run AFR 225 heads. I think my heads might limit the power up top.
3) My fast manifold already has nitrous bungs. Forged internals means I can spray a huge shot (200).
4) 480-490 rwhp max without spray.

Maggie
1) 122 Maggie $6K plus new hood $1.5K.
2) 550 rwhp on stock LS2s with exhaust only.
3) No nitrous bottle to refill.
4) How close am I to the LS2 limit:sm_up_there:

Are you still planning to run your car on road courses? If so, stay away from the blower. If not, the blower is a great choice. Besides, you can always upgrade the heads later.

[SeanPlunk]

I still think a good N/A build would be best for you. Clearly you're much more into road racing than drag racing and I think a built N/A motor is better for road racing :D

[Vettezuki]

Cough, cough, I think it was my suggestion :leaving:, but since Sean agrees, it must mean one of two things:

a) it's the greatest idea ever
b) the Universe may implode

[Leedom]

Are you still planning to run your car on road courses? If so, stay away from the blower. If not, the blower is a great choice. Besides, you can always upgrade the heads later.

What are the draw backs on blowing a road racing motor?

Cough, cough, I think it was my suggestion , but since Sean agrees, it must mean one of two things:

a) it's the greatest idea ever
b) the Universe may implode

It is not looking to good for any of us. :sm_up_there:

[SeanPlunk]

What are the draw backs on blowing a road racing motor?

Generally they're more sensitive to heatsoak and also add more weight to the front of the car. Also, power delivery from a N/A powerplant is usually more linear than from forced induction (which is why Gordon Murray demanded an N/A powerplant for the McLaren F1) which is better for road racing.

[94cobra69ss396]

What are the draw backs on blowing a road racing motor?

Sean said it.

[Vettezuki]

Sean said it.

Plus real men don't need to force anything. :smack:

[Vettezuki]

Oh, Carlos, just rememberd. The guy who built the H&C LS1 in my Vette, now has a forged 402 Twin Turbo in his C5. As I recall he went with a Scogg & Dickey (mmm, spelling) supplier out of TX . . I think. Apparently the same specs as the A&A, but a bit less. I'm going to see if I can get him to come out on our cruise, but the weekends are family time for him usually.

[BRUTAL64]

:popcorn:

[enkeivette]

Your motor sounded like a high compression build to me. Unless you can get the CR down to at least 9.5 with a HG I would build NA. I know magnachargers are efficient and yadi yadi but unless you can put 8lbs on it safely using only 91, not worth it.

[BADDASSC6]

Sorry dude, No high compression motor here. It was intentionally left at the factory compression because there was a possibility of adding a blower later. I am impressed that you can hear the difference between a high and average compression motor though.:drink:

[Vettezuki]

BA, is the A&A Cam a custom grind or an off the shelf unit?

[enkeivette]

Sorry dude, No high compression motor here. It was intentionally left at the factory compression because there was a possibility of adding a blower later. I am impressed that you can hear the difference between a high and average compression motor though.:drink:

Well I'd be willing to bet that even a stock LS2 has relatively high compression. Not that I can hear a difference, but since your motor sounded raspy and lopey I assumed that you would have upped the compression to compensate for that monster cam you've got.

I guess now it's a good thing that you didn't. :beer:

[SeanPlunk]

I think LS2's are 10.9 to 1 stock

[Vettezuki]

Carlos, would you consider a High Nickle steal block? I know a place that will build a complete 402, fully forged, short block for $3k~. A set of AFR like 225 heads is $1,500. So that's about $4,500. You could sell your LS2 Long block for about $2k (I think, maybe a little more, maybe a little less). So you might be able to get into a 402 Short Block w/Heads for less than $3k net. This block is good for something ridiculous, to like 1,500HP all day long, so you could spray in stages up to absurd levels for the strip, but keep the 402 NA for the road course. Yes it's heavier than the aluminum block, roughly 100lbs I think.

[heypal]

Without question do the 402 specially if you want to still be competitive...Well more competitive then with the blower. Heat soak sucks so does the added weight. Also n/a motors are great for the track if cammed right and built right. You should hit up Ryne at CMS. He is like the so cal god of lsx motors/cars just pick his brain.

Their website sucks but he is into making gm cars faster not websites lol.
http://www.cunningham-motorsports.com/
Ryne Cunningham
Cunningham Motorsports
Specializing In Late Model EFI Performance.
Lake Elsinore, CA
Shop: (951)471-2898
Cell: (951)375-2453

Ryne-CMS@Hotmail.com

[Vettezuki]

Carlos, would you consider a High Nickle steal block? I know a place that will build a complete 402, fully forged, short block for $3k~. A set of AFR like 225 heads is $1,500. So that's about $4,500. You could sell your LS2 Long block for about $2k (I think, maybe a little more, maybe a little less). So you might be able to get into a 402 Short Block w/Heads for less than $3k net. This block is good for something ridiculous, to like 1,500HP all day long, so you could spray in stages up to absurd levels for the strip, but keep the 402 NA for the road course. Yes it's heavier than the aluminum block, roughly 100lbs I think.

heypal has given some good additional info.

About the steel block I'm talking about, it's also siamese bored. It's pretty much a full on thrasher block. Can go up to 463ci.

[BADDASSC6]

I think think a steel block would be what I'm looking for. I am pretty sure that I will be going with the 402, but I'm thinking of just buying the cam and rotating assembly and having it assembled. A 463 would be bad ass, but at that point I would just go with teh LSX block.

[Vettezuki]

I think think a steel block would be what I'm looking for. I am pretty sure that I will be going with the 402, but I'm thinking of just buying the cam and rotating assembly and having it assembled. A 463 would be bad ass, but at that point I would just go with teh LSX block.

Would be or would not be?

I'm pretty sure a 402 stroker kit (a la Lunati) into your stock LS2 block will require some minor notching, if not machining. The $3g I mentioned is a 402 assembled steel block. I'll PM you with the contact info should you wish to follow up any further. Let's say the block bares some striking resemblances to the LSX block. . .

[BADDASSC6]

My bad I was rushingbecause I was posting from work. It is not what I'm looking for. The Aluminum blocks are good for more than 1500hp (not rwhp). I heard that steel block will make more power at those levels due to distortion with the aluminum blocks, but I have no intention to go there.

My understanding was that NO machining is required for a 402 build. Now most shops will do some clean-up work, but no clearancing is required.

[94cobra69ss396]

Ben I think what you are talking about is a high-nickel iron block, not steel. I've read that the high-nickel LS-X blocks can handle around 2500hp.

[SeanPlunk]

I think for what Carlos is doing that a stock block will be the best combination of low cost and light weight.

[94cobra69ss396]

I think for what Carlos is doing that a stock block will be the best combination of low cost and light weight.

I agree.

[Vettezuki]

. . . My understanding was that NO machining is required for a 402 build. Now most shops will do some clean-up work, but no clearancing is required.

This is not my understanding. I thought a 383 was a drop-in, but a 402 required something to be cleared, but I certainly don't know for sure. :huh:

I get it about the aluminum, I was just trying to think of a clever/cheap way to do what you want while having the potential to go into the stratosphere. :drink: BTW, the builder said the weight difference in the block is only 75 lbs, the same as the difference between a an aluminum and iron Gen III.

iron vs. steel
Good point. I get a little sloppy with alloys. What's the difference between cast iron (high carbon) vs. steel (low carbon). I mean, when/how does one become the other? Time for some Wiki or How Stuff Works yee ha.