Kmaroman

iTrader: (1)

omg i don't know if ican wait till tommorow to see it. what was that saying saying the lt1 was touched by god and the ls1 was made by god. Then where does the lt5 stand, i don't know much about the lt5, and from what i hear there nothing like lt1 or lt4 and designed by lotus or something different bores then standerd 350s. but i do like the fact that my friends says lt1s are inferior to ls1's next time i'll be like oh yeah what about an lt5

Dark Shadow

at one point GM owned lotus not sure if they still do. gm built the LT5
lt5 are a dohc motor. it has 16 injectors and 16 ports intake ports in the manifold and heads, and 32 valves. think of it kind of as a honda motor(no offense) you use all 8 cylinders but only 8 injectors and 8 ports till the motor pulls enough vacuum to open the remaining ports and then comes the last 8 injectors as well.

Toronto_LT1

iTrader: (-1)

holy crap!! that thing is going to be a screamer! make sure to post vids.

Dark Shadow

i will. deff high res pics will be up tomorrow. not sure on vid but that will be up shortly with in a couple of days just making sure everything is ready to fire it up.

Lol just remember this thread we we open up shop. you guys will have a new sponsor hopefully soon.

im still confused of vr1 racing oil 30w if its synthetic or not i read the bottle up and down and dosnt say anything about the oil.

Formula350

iTrader: (3)

All I know is, as far as being touched or built be, the LT5 was Lucifer's making

Lotus designed it, started in 1985! First came out in 1989 under the 1990 model year. BORExSTROKE is 3.9"x3.66". So more stroke and less bore. Also is an aluminum block, and has the starter under the intake, like on some of the caddy motors. Shared our SBC Moto though 1-8-4-3-6-5-7-2 Um... Oh, was 2 bolt till I think 93, which is also when it got a impressive power jump from 375hp to a bit over 400. One thing I found odd was it's use of dual timing chains. It used the normal style SBC crank-to-cam, but the 'cam' then was another sprocket that then drove, what looked like 2 more chains. I'm having a hard time finding a pic though to find out if it's 3 total or just 2 total.

heh I actually didn't know it had 16 injectors. Seems a bit strange they'd do it that way, but I guess I don't fully understand the LT5 enough to see as to why the extra 8 are needed. It's still an 8cyl, and I'd think the 2 per cyl would still fire at the same time (at high enough vacuum, or in other words under heavier driving), as a single injector would. So why not just do what we've done, and run big *** single injectors? I'm sure the 3.8 Turbo's injectors would've sufficed. And while there's the "It has 16 individual runners" bit, they COULD'VE just siamesed the ports till they met the head. They siamesed the exhaust after so far so it exited as one port.

Anyways, it's really fun reading stuff on the LT5. It's such a crazy motor. GM's first NEW motor in 20 years (when it was released, or maybe from when it was designed *shrug*)

EDIT: WTH, am I reading this correctly?!
"An alternator, air conditioning compressor, gear-reduction starter and a distributorless ignition system are located in the valley between the heads. "

They all are under the intake? >_> I mean, I knew the starter was, but how is the alternator and A/C compressor driven? From this pic it sure doesn't look to be the case: http://www.zr1netregistry.com/454.04.jpg

Also, it is a tri-chain driven timing setup. Crank to "Idler" sprocket, then 2 off the back of it.

Such a great read here: http://www.zr1netregistry.com/firstking.htm

Forgot to add, which the article brings up, is MerCruiser (Mercury Inboard I think is another name for them) built the LT5s all by hand.

EDIT: OK this sheds some light on the Alt and AC. It's not between the heads as the author makes it sound. http://www.zr1netregistry.com/454.06.jpg

Formula350

iTrader: (3)

Did some quick digging for you, and from what I'm reading on Valvoline's own site, it does NOT seem to be a Synthetic.

Here's a PDF on the "zinc" additive.
http://www.valvoline.com/downloads/2008-003a.pdf

The Site for the VR1
http://www.valvoline.com/pages/produ...asp?product=50

Basically this is what leads me to believe it's a "standard" oil.

"Valvoline offers two solutions to the zinc issue

Valvoline Racing VR1: 75% higher zinc than SM engine oil with a balanced additive package designed to work in both racing and street-legal applications. This product will protect older style push-rod and flat tappet engines. Valvoline provides this product in both multi and mono viscosity grades: SAE 20W-50 (part vv211), straight SAE 50 (part vv235), SAE 10W-30 (part vv205), SAE 30(part vv223), SAE 40 (part vv229), and SAE 60 (part vv241)

Longer-Lasting Zinc/Phosphorus: Valvoline uses an advanced zinc/phosphorus additive that keeps higher levels of phosphorus in the engine oil where it protects the engine, instead of poisoning the catalytic converter. Valvoline is the only brand offering this unique additive across its entire line of passenger car engine oils, including SynPower which is the only synthetic offering this additive."

Basically, they have the standard oil, being VR1, offering the higher zinc than current oil formula. And then also their SynPower line using it, which since it says "SynPower which is the only synthetic offering this addative", leads me to believe that VR1 then is not a Synthetic.

TADA! to the rescue! (not a bash on you, just a praise on google )

Dark Shadow

only the starter is under the intake manifold.

Dark Shadow

lol thank you for the info i never even thought about searching google. dont know why b/c i usually do.

tensecondz

iTrader: (1)

Valvoline Racing is not Synthetic....

With the LT5, I dont think you are running very high valve spring pressures etc.. as its a DOHC.

Your main concern should be an oil that can take high heat due to the turbo(s)

Your best off the shelf solution would be Mobil 1 Truck and SUV 5w-40 which is also Delvac 1 (Diesel Oil).. Very very robust oil,,, strong additive pack and great base oils to deal with high temperatures..

Run the motor for a few hundred miles with the VR1,,, then switch.

Dark Shadow

sorry no vids today thursday will be the day that it will be running

KriegerEhre

iTrader: (3)

jesus christ that's a damn jet engine!

krayzie7th

oh dear... that
is just freaking beautiful!! i wish i had that. Keep us posted.

tensecondz

iTrader: (1)

While your asking about oil,,, Don't forget to get rid of that Fram. Even if the cardboard end caps dont fail, the anti drainback seal is marginal at best and with your oil filter completely upside down you need to upgrade. Get a WIX or M1 oil filter.

P.S. SICK PROJECT!!!!!

Puck

iTrader: (17)

They do not always fire at the same time, it is for the increased fueling at high rpms, to suppliment the normal injectors. That way you do not have the issue of tuning huge injectors to idle properly if they do not like the very short pulse width needed at idle and low rpms. Can't just combine the runners right before the heads either - the logic of a standard pushrod V8 does not work with a DOHC v8.

Just like on a modern sportsbike. My ninja has 4 injectors that run all the time, and another set of four secondary injectors that only kick in at 12,000rpm and above. Also an excuse to wind it out every once in a while - dont want those poor neglected secondary injectors getting all clogged! .

No doubt that they knew what they were doing when they designed that engine.

RyanA

iTrader: (6)

And don't forget, the LT5's got the "valet key" You could turn it into valet mode and it only used 8 injectors and drastically cut power output. Kind of cool that they had all this down in the early 90's. My boss had one and let me drive it; he told me to make sure to put it in "full power" mode every time I started the car. I guess the earlier ones you could turn it on valet or full power and it stayed there. However, the newer ZR1's actually reverted to valet mode every time you turned the car off and restarted it. I never really got on the car much; just enjoyed driving it around for the day. They definitely sound nice...

Kmaroman

iTrader: (1)

those pics make cry tears of joyy, maybe my next vehicle i will be lucky and find and idiot with an lt5 forsale

Dark Shadow

you can buy a new one for $20,000 theres a couple left from gm that i heard of.

phirepower

iTrader: (2)

I am truly sorry that I ever doubted you...

Formula350

iTrader: (3)

You got what I said, backwards. I didn't say combine at the head, I said split at the head, combine it in the runner then split at the head. Just like what people do with TPI motors, which is a OHV and is feeding two different cylinders instead of the same one in the LT5s case. People siamese the runners all the way from the plenum to the intake and then even cut into the intake some. Helps power quite a bit. You could still use a single injector and the computer controlled throttle plates to the secondary intake valve.


Dark: Are you going to be re-doing the plumbing from the turbo to the intercooler? That looks quite large to fit in the car, and appears to have far extra pipping than needs to be. Going from my friend's Vette's engine compartment, I just can't see all that fitting how it sits.

Dark Shadow

lol no prob