kris72079

iTrader: (7)

I am getting ready to dig back into my lt1 because I can't leave well enough alone. I am debating 383 or 396, however, I keep coming back to 396 so I think that's where I'll go so I'm not kicking myself 2 weeks after start-up.

Understanding that I'm going to get more "do a search", "read, read, read", & "you don't have deep enough pockets" posts than anything, I am looking for legitimate advice from anyone who has taken this on already.

To answer some questions before they arise, I'm M6, Moser 9"/4.30/trutrac already. That is supported by PST driveshaft, adj lcas, adj panhard, and subframe connectors.

I'm planning on focusing on the bottom end unless I have something seriously flawed on top. I currently am running AFR 195's (2.05/1.60), 1.6rr, ported Edelbrock Air Gap, 58mm AS&M tb, AS&M mid lengths (debating LTs). I also run a Nitrous Outlet plate kit which I intend on retaining. Obviously, plan on forged, but here's where the critics chime in. Although I'd love to drop in a Callies or Lunati crank, I'm pretty sure I'm going Eagle crank and rods, Howards pistons, and Mahle plasma-moly file fit rings. I will let the pros spec out my cam as well as supporting equipment to go with.

In comparing the flow results of the AFR 195s with renowned LE3's it appears on the surface that the AFR heads flow better (280/218cfm @ .550lift-AFR vs 280/195cfm-LE3) so it seems to me that I have enough head to support the 396 already?

This is going to be a primarily street application with maybe 2-3 trips to the track a year. What does everyone think?

ahritchie

iTrader: (1)

Do it...go 396! I'd get those AFR's ported which would be icing on the cake; that or sell them and get some Ai 200cc factory ported heads instead.

joelster

The AFR 195's will work on a 396 but a bigger head will make much more power without sacrificing much of anything. I would go with a set of 210's or 227's, but 227's up the price substantially due to the need for shaft rockers and specific pistons with the proper valve notch placements. See if you can sell the 195's and pick up a set of 210's. I figure you could get $900 or so for the 195's without too much trouble. You can find 210's for around $1700 if you ask around. How high do you plan on spinning the engine? The stock pcm is all done by 7k.

ahritchie

iTrader: (1)

Real question is what is the HP goal exactly? No need to spend more than what you need, it would be a torque monster regardless of what you pick.

kris72079

iTrader: (7)

Geez, I'd hope I could get $900 for the heads if I were to sell them...which I wont, they've only got about 1000mi on them, brand new! I do wish I went with the 210s when I bought them (everyone's story, right?) but hindsight is 20/20. I don't figure I'll need to be north of the 7k range, the stroker ought to start making power low enough to not have to spin it way up high, right? Suppose I want to, am I looking at ltcc beyond it?

kris72079

iTrader: (7)

Who doesn't shoot for the moon and settle for something just short? If you don't then you're either 1. unrealistic; 2. not trying; or 3. naturally wealthy. That being said, I'd say I'm shooting for 500hp at the wheels, hoping to get as close as possible without getting stupid (it is a mostly street run car), and then of course putting a 200 shot to it.

96capricemgr

iTrader: (1)

How are you going to feel about coming up much more than a little short, like 100rwhp short?

Puck

iTrader: (17)

195s wont make 500 to the wheel on a 396 without a LOT of work and a pretty nasty cam. Too small, you are looking at more like 450.

For your goal, you are looking at a healthy solid roller and ported 210/227s.

ahritchie

iTrader: (1)

Advanced induction claims up to 500 RWHP on a properly built 396 with ported stock 200cc heads on their website (with solid roller cam I'm sure), if there's any truth to it, I dunno....but yeah, better to overshoot a bit with some big aftermarket heads if if you really want to hit the magic number.

96capricemgr

iTrader: (1)

They have had multiple engines up in that neighborhood even at least one down around 355ci and several 383s some solidly over that number through 8" non-lockup converters. When you look at actually fast cars 396s are not represented as much as most newbs would expect.

That said I think there was a hydraulic 396 they put a topend on that made near 500rwhp but broke something serious on the car before it saw the track.

kris72079

iTrader: (7)

Again, I realize the number of 500rwhp was a lofty goal and I expressed that I probably wasn't going to make it there but I'd like to believe that 450 is attainable. Again, I'm not going to take a huge bath on the heads just to squeeze out a few extra ponies. I will however, take the advice and have the heads opened up a little to try to gain some there. I knew the heads would be a point of restriction but honestly was surprised to see them having a higher flow rating than LE3s. Lets bounce around the discussion of solid roller vs hyd as this is something that I just recently started investigating recently. What to look for? Pros? Cons?

DUDCOUPE

I see no reason why you cant have 500 rwhp. Id get lt4 heads and have them opened up alot and get a edelbrock lt4 intake. Youd be stupid not to go with long tube headers. Id get some kooks 1 7/8 headers and run it into a decent flowing mufflers. Gonna need a decent cam, and a bullet proof valve train (good rockers, pushrods, lifters, etc). Nothing for nothing but if i had a 396 stroker motor and it made 450rhp id push it off a cliff

HellTeeOne

Flow numbers are only part of the story, don't get too hung up on them. 2 different heads can flow similarly on a bench and make dramatically different numbers once they're actually bolted onto an engine and run.

Making at or near 500rwhp with a stroker LT1 has been done many times, even with a hydraulic as noted.

If using a solid roller cam, it can be done pretty handily with the Ai200 heads. If using a hydraulic, yea it takes a lot of cam but your best shot will likely be the Ai TFS heads, they're the only ones I have actually seen results at and near 500rwhp in street applications with a hydraulic cam.

Ai quit cutting the AFR heads some time back, not sure what the reason was. If you could get a high quality port job on those 195s it might be enough to get you close.

Either way, I'd say it's highly unlikely you'll get close without some high-quality third party porting on the heads, no matter what casting you choose.

Get with one of the LT1 head porting pros, tell them your goals, and ask them to design a top end and camshaft package that will meet your needs.

93M6Formula

Ported LT4 anything will not get you there N/A.... Don't give the OP false hope.

Puck

iTrader: (17)

Where are all these magical 500rwhp stock casting LT1s, especially the hydraulic ones?

I'm hearing about tons of them but I'm pretty sure you can count them on half a hand, rounding up.

If a company is selling a product, don't expect every one to match the cherry picked advertised one. 99% of people won't make anywhere near 500rwhp with a street HR on ported stockers, no matter who did the heads.

DUDCOUPE

^thats because people are nugget builders.

Puck

iTrader: (17)

I'd have a hard time finding a worse build for the money then the LT4 heads/Edlebrock intake you suggested.

joelster

I'm right around 500rwhp with an auto. No I don't have a dyno sheet but my car traps upper 133 range in good air and 130 in heat/humidity at 3075lbs. Run it through all the calculators you want and you'll get from 500-530rwhp. I'm running the stock pcm which limits me but I also run a single plane intake and a solid roller. I don't know of ANY 500+hp N/A LT1's that run a stock style intake, ported or not. They may be out there but I have never seen any. All of the fast N/A guys that I know of, myself, Mike V, Brady M, Taner, Carlos, etc,etc all run a single plane. None of us run stock ported castings either. Maybe we're on to something?

If I were building a 396 to get 500rwhp, It would have a single plane, a solid roller (nothing crazy), 12.5-1 compression, AFR 227's or comp ported 210's. I would seriously look into an aftermarket pcm like a FAST XFI or Holley Dominator setup to get the rpm range over 7k. If you do that then the hp goal can be reached easier. Other heads to get you that number would be the AI TFS heads.

kris72079

iTrader: (7)

Regardless of the argument, I am sticking with the AFRs most notably because I own them, they are new, and I own them. Why throw out a $1800 set of heads to buy another set and have them worked, when I can just work the ones I already own...Might I come up a bit short after machining, maybe but was I better off, probably. Risk I'm willing to take.Did I mention I already own them? I started this project with a ported set of LT4s, yes, lt4s NOT lt1s and a ported Edelbrock intake. The heads have hit the road because of potential issue with the #8 dome and the intake is what it is.

kris72079

iTrader: (7)

Again I'd like to stick with my 195s and invest some money in them as to not get hammered by swapping them. By going away from the stock style intake takes me away from my existing N2O setup as well. So many variables! I would like to hear about your build if you care to share...