Jeremy85

Because the elevation makes 9.5:1 here equal to 8:1 at sea level, because the flat-top pistons help everything, compared to '76-'83 pistons, because the L69 cam has great specs for this, and because this plan is so affordable.
I'm waiting on stainless headers from EBay, but these aren't turbo headers, just shorties.
This is a non-emissions build, first with 416 heads, later 906 or 062. Blow through with n Edelbrock 1406.
The cam I ordered is Howards' copy of the L69, so slightly less advertised duration, (reduces overlap triangle, good for older-design turbos with more exhaust backpressure than boost pressure) but correct at 0.050", correct LSA, a hair more lift added, 5* too much advance, but I have a new Cloyes timing set with a 4* delay keyway.

Jeremy85

I have a Performer EGR manifold, so that needs to go. Holley or Weiand used to make a low profile single plane with a plenum divider, that's the one I'm thinking of trying.

Street Lethal

iTrader: (16)

Not abnormal at all. Was going to do this years back while tuning the stock PCM and using the original cc-quadrajet, but decided to sell the carbed cars that I had. Looking forward to this build...

Street Lethal

iTrader: (16)

Try to get your hands on a used Holley/Weiand X-Celerator, or Edelbrock Torker II single plane. They're both low profile, and decent intakes. Can't believe they are still going for what they are brand new because they aren't the greatest of intakes, but they must still have a demand for them. What are your plans for fueling, and how much power are you looking to make...

Xter

+1

The Weiand X-Celerator intake provides a lot of hood clearance. I'm running one now and with a stock hood there is a decent amount of room.

A single T04E seems very small though in my opinion if we're talking the EBay turbos. I have two of them laying around and they seem like they'd choke the engine out very fast if you don't run twins at least. I'm sure it'd spool almost instantly off idle but outside of that, I don't see much good coming out of running just a single. That's just my 2 cents.

Orr89RocZ

iTrader: (20)

Yeah thats very small turbo. I would feel better with slightly larger. T3 60-1 or so. In fact could run a t4 60 mm p trim with a .68 housing from on3. Spool would be good

Jeremy85

I must admit to being a newb to adding a turbo to anything, but I have been studying, a lot. From my read of the compressor maps on the old Turbonetics website, the 4E-57 looks ideal to me, here's why; what I'm seeing is a snail that can feed 200-400 HP at 2 Bar at 70% efficiency. That equals 100-200 HP with no turbo. Then, since the elevation reduces air density, a 200 HP egine up here is a 225 HP engine at sea level. I've seen a dyno number for an L69 with a Comp DEH255 and a Performer 2101 making 225 at the flywheel.
From this it seems to me that a 4E-57 is as small as I'd want, but not too small. And at what RPM will my 305 start making 100 HP? Simple math suggests it should be below 2400, which I like the idea of. 200 HP by 2400 RPM sounds good to me.
My experiences with cammed engines haven't been good, I like an idle as smooth as new silk, and all the idle vacuum I can get, so a divided plenum is an absolute for me, however much HP it may cost.
An engine good for 21" of idle vacuum at sea level makes only 18" here, that's as big a loss as adding 30* of duration to a cam.
I'm pretty sure I have a chrome Holley mechanical fuel pump I can drill and tap to boost-reference, I need to order some Nitrophyl floats for a ThermoQuad.

Orr89RocZ

iTrader: (20)

Compressor wheel likely could feed that level fine but i feel the turbine wheel is small for the cubes. It would run into some backpressure issues which is hard on motor thrust bearing.

I ran a t70 turbo on a rear mount stock LB9 tpi 305. 220-230 hp stock? Felt very slow stock. Even with that turbo at the rear bumper, it was making 2 psi half throttle or so. Front mounted with all that extra heat energy, it spool even quicker. That was a p trim 64/74 turbine and a 70 mm inducer comp. granted its way more compressor than you need, its pretty efficient to 500 hp. 7-8 psi boost REALLY wakes up a 305. Low 13's vs low 15's. 20 mph gain in 1/4. Turns it into a bolt on ls1

You can try the t04. Get the largest turbine housing made. If you can choose. Not sure whats available. .82 ar or bigger be nice if possible. That thing wil make instant boost. Run a big wastegate

Jeremy85

Thanks, Orr!
It combines a T3 turbine with a T4 compressor, right? If so, shouldn't it be easy to use this compressor with a T4 turbine, do you know?

Orr89RocZ

iTrader: (20)

I dont know if anyone is swapping turbine wheels with stuff like that. You can try to find whatever the largest t3/t4 compressor and turbine as possible and use it. One of the large trim stage 3 or whatevers. Likely wont rpm alot but could be enough to make you happy

Orr89RocZ

iTrader: (20)

https://rev9power.com/force-inductio...d-exhaust.html

This would work

junkcltr

iTrader: (1)

I agree. I had two T04E-57 on a stock LB9 and the turbines were corking the output.

Jeremy85

Ok, CX Racing has something that might make a better starting point, it's a GT35, but unlike most other GT35s, it uses a T4 turbine for more exhaust flow, while still being a 0.68 a/r for quick spooling. And unlike most of the cheapest turbos, which are oil cooled only, this is also water cooled. It takes a 3" V-band.
I'm not finding anything closer to what you guys suggest without spending 3 times as much.

Orr89RocZ

iTrader: (20)

Cx has a bunch of cheap turbos. What specific gt35 is it? If its a 60+ mm turbine it could work

Jeremy85

https://www2.cxracing.com/TRB-GT35-T4-68

looks like the turbine is 62 mm.
Thank you for advising.

Orr89RocZ

iTrader: (20)

That will be perfect imo. Instant spool and strong power for what you are doing

Evilokc

small turbos spool quicker and give more acceleration and larger give more top speed. at least that's my limited understanding. so a small turbo is a lot of fun on a driver because it adds pep and a big turbo is fun is you have a place to go really fast.

Jeremy85

Now, I'm on vacation for a week, so I can start on my 305. There's some disassembly to do to install the new Howards L69 cam, and since EGR doesn't play well with boost, I'm leaning toward a new Weiand 7547-1, which is an older design low profile single plane, much like a Torker 2 from Edelbrock. But I had the idea that it had slots for plenum divider plates, turns out those were for the 7546, which doesn't interest me at all. Maybe a Performer EPS would be a better match for my 416 heads and mild cam?
I'd be money ahead to just plug the EGR on a stock intake, but I'm willing to invest in a new manifold to rest easy about not having some cylinders running lean under boost. Too many good choices. Maybe it'd be best to run TPI on megasquirt control?

Jeremy85

About 10 days ago I hurt my back, I'm not all better yet, but I'm working 4 hours per day, so I hope to have pics of progress soon. I've decided on a Weiand intake, because the Weiand is about a third of an inch shorter. I haven't ordered it yet.
DNA sent me the stainless shorties for a second gen Camaro, I sent them back for the third gen version, which may be the same item with a different sticker on the box, but the correct ones are about $7 more. That part didn't bother me.
I'm hoping to have it boosting by Halloween. Some years we have had several inches of snow by then, but we normally get some decent days in November.
If it doesn't break anything first, I'll consider it a success if it can spin both rear tires through second gear on cheap tires.
I don't want to break my 700R-4, which is already in and known good, but I'm not sure about attempting the 4L80E swap now.

Jeremy85

It's the 8120 Street Warrior that I'll be trying.

Jeremy85

I've been reading about overlap cams with turbos, there are so many different theories, but as I read about what guys are actually running, what they're happy with, what's easy to tune, the one trend that can't be denied is that there is such a thing as too much overlap with turbocharging.
I found a pair of 906 Vortecs I couldn't refuse. The truck ones with Inconel exhaust seats. I paid $90 for the pair, still assembled, no visible cracks even after wire brushing with solvent.
These supposedly have less exhaust flow, especially around 0.120" lift, but oh well.

Jeremy85

No progress due to an embarrassing bout of unemployment I find difficult to admit to, but plenty of time to think, research, plan, dream, and prioritize.
I'm now employed again, for adequate pay, and unsurprisingly needing to catch up on delinquent bills before ordering speed parts.
However, I've made progress on what I have, and I have confirmed that I have flat tops, a non-GM cam, a double-roller timing set, no vacuum leaks, and no failing lifters or rocker studs in my 305, which is the original, and has no provisions for roller lifters but has the 1-piece rear main seal.
I'm not proceeding with the Howard's L69 cam, I'm trying the Melling 22135 retrofit hydraulic roller. 265/274, 206/214, 112, 470/490. It's ground on a 108 but I will start with it at 112.
My back is all better, but the 4L80E swap will wait until next summer, even if I break the 700R-4 before then.