CradleofFilth08

I currently own a 92 Z28 with the L98...the car is stock other than the usual aftermarket KYB struts and the gear swap. I went to a 3.42 and the flowmaster muffler...

I've decided to go the route of a Vortec HSR. I have Vortec heads already, just need to be built...I am looking at possibly, shorties to a true dual and maybe a trans build.

What I'm wanting is around 350 Hp and not that much loss of TQ. How should I build my heads and what size cam do I need for a good TQ curve and a nice lumpy idle?

I only know what I've read and what I've been able to ask my dad about. I'm about to start school for Automotive Tech. so I'll be able to understand more in about a year.

vetteoz

iTrader: (13)

Very little needs ( can ) be done to Vortec heads to improve them for street engines
If you intend running more than .480" valve lift then mods need to be done to heads to allow that greater lift

You are aware " lumpy idle " and the computer for EFI don't go in the same sentence?

antman89iroc

I agree with the previous post regarding lump idle and a stock computer tune. Get into prom tuning and that's a whole different story.

Besides, with the gears you have, HSR, and the (smart, in my opinion) decision for a torque minded build~ you don't need or want a lumpy idle. My build is with a 212/218 CC and it has a nice idle. Fairly smooth but noticable. It doesn't sound stock. But even that cam takes computer tuning so you may as well get used to that. If I were buying my cam again today I would probably opt for around 218/224 cam. I think it will bring the engine into a rpm range better suited for the HSR. Now this intake isn't a high rpm screamer either. I think of it like a good flowing dual plane intake from the carb days. You can make good streetable power but it's not an all out drag setup.

And he is right about the vortec and lift. Do your research. There are a couple of things you need to do as lift goes past about 480. And don't get all star eyed about certian specs and HP numbers. You are going about it in the right direction. Pick a good quality cam company like comp cams and follow their reccommendation regarding spring & components. One of the mistakes I made was trying to save $$ here and there and ended up having to buy parts twice. (like rocker arms)

CradleofFilth08

I guess as far as the lumpy idle...I like the sound of a non-stock idle and from what I"ve determined from the different videos I've seen and people I"'asked, lumpy was hopefully, the right term.

I have no idea on how to program and I would have no idea where to start, if there's a particular method or brand of burner that is used then I'm all ears for that.

For your build, does it perform a lot better in higher RPM's than the stock TPI setup? Because when you say not a high RPM, I think of 6500 and down.

Most of my driving will be around town and maybe every other Friday Night at Atlanta Motor Speedway while FND's is in season so that sounds preferential. lol

antman89iroc

Yes the HSR moves the peak rpm band up ~500-1000 rpm but the cam is really what determines peak torque/HP band. With my cam I shift at 6K but that is about 500 past peak. For my setup I would be better off with a bigger cam to match my rear gearing or going down to 3.37-3.45 ratio. My 1st gear is pretty much useless and all the extra gearing just means I end up in a higher tranny gear around town. Still "cruise" at 1800-2200 most of the time. Why build a motor that doesn't start to come alive til 3K when you can't realistically use it. Too radical a cam and you have to keep it in a low tranny gear to make it happy.

Orr89RocZ

iTrader: (20)

I like that 218-224 or similar cam on a tight 108-110 lsa. That will give you a good torque curve and be tuneable. Give you a 6000 rpm shift or so. Give it 3000 stall for better track performance

CradleofFilth08

I got a new job and was waiting for the Summit Racing scratch and dent sale to see if they had any HSR's...I can dream. lol But anyway, I was looking at heads after I finally got curious about AFR's...I'm seriously debating saving up for a pair.

Would a set of the 195's be better than their 190 Vortecs? The reason I initially wanted Vortecs was because they were a quick way to net high horses over the stock L98 heads but with that being said, both of AFR's are intended for racing, so is there really thin fine line between them? I've looked at the numbers (which are still Greek to me but I try) and they seem to be flowing somewhat the same. There's only so much I can learn from Google searches that lead me right back to TGO on discussions where AFR's pop up.

dacuma

You might want to rethink the Vortec HSR intake, I'm doing my build right now, and run into a wall!!! Due to the poor quailty of the intake!!!! I've had about 5 to 6 intakes sent back due to poor machining. Makes me mad due to the fact that I was running the first gen of HSR and never had a issue. Sold it due to go with the vortec style, and then problems!!!!You guys can check out my build and problems I ran into here.

https://www.thirdgen.org/forums/memb...ealth-ram.html

It's in members camaros. Well just want to give you a heads up, I don't want anyone else going thru this same issue. Anyway I called Holley to see if any there is going to be anything done to correct these issue. I'll let you guys know. I might be going with a different inake, I don't know yet. Still blows due to the fact I'm set up to run the stealth ram already. Just giving you a heads up.

CradleofFilth08

Depending on what Holley does to solve your dilemma, I might just go and buy a pro-flo xt.

dacuma

Yeah don't know if you seen that link on my other post,it's a pretty nice set up, just alittle more fab work needed for it. I'll keep you updated on what Holley decide what they are going to do. I'm not getting my hopes up though.

InfernalVortex

iTrader: (4)

Ive heard some fairly negative comments on the pro flo's ports... allegedly somewhat restrictive. I always figured Id go with a stealth ram but man thats a real dinger in the dingers to hear that the best affordable EFI intake for Vortecs is so awful. Are there any decent single-plane EFI options for Vortecs? I thought I remembered one but it was pretty pricy, but maybe not. I know there are some that have the bosses for nitrous injectors, but are not drilled/tapped. Would be kind of a PITA to do all that from scratch I think.

toxik IROC

iTrader: (12)

Take a look at this build, alot of good info and alot of other that have done similar builds have chimed in too.

https://www.thirdgen.org/forums/tech...iks-build.html

dacuma

toxik IROC (I just thumb thru your post, you motor looks sharp btw!!)

The HSR is a great set up, don't get me wrong. Matter of fact I had one of the first batches back in 03 when it first came out. You couldn't even get the adjustable fp reg, with the fuel rail kit at that time, and had to drill out the center holes for late model heads lol I loved the look of it, the powerband increase the whole nine yards. The quaility of it was great. Like I said I ran it since 03 never had a issue. So when it came time to upgrade my motor, I wanted to go with the vortec heads. (so I would have to switch to a vortec intake. ) This is where everything went wrong. The new weiand vortec intake machine work is terrible. I've had about 5 to 6 new intakes sent to me with the same issues. Mating surface uneven, due to sloppy machine work, and some chunks missing from them, or fuel rails with injectors wouldn't bolt up.

Bottom line is this, if you can find a new or used Vortec Stealth Ram, (older one would prob be a better bet) that doesn't have these issues go for it, I would. Trust me it would make my life easiler. But from what I seen, I don't there are any that are new. Even if you guys look at their home site photo of it http://www.holley.com/data/products/.../large7542.jpg

if you blow up the pic full size you can see what I'm talking about. And this is on their website!!! I'm really disappointed.

toxik IROC

iTrader: (12)

Thanks buddy ^