Engine & Gearbox combination

[Heidelberg]

OK all you darksiders out there.... Can I ask you for your views on what engine/gearbox combination I should put in a Australian spec'd Superformance Cobra for WA?

I've just ordered a Superformance from CTC and have made all the decisions that satisfy the look I'm wanting to achieve (Black, no stripes, Roadster bumpers, Roadster dash layout, Polished 17's, silver ceramic sidepipes, twin roll bars, ect...) but I now have to decide what drivetrain I need to install on the roller once it arrives in Australia.

Here are a couple of facts that I'd like to share in helping you give me your opinions!

From reading this forum religiously for about 5 months now, it's become plainly obvious to me that I do not posses the technical knowhow nor the skills of probably 90% of the contributors to this forum and therefore would like the simplest and most straightforward install possible! I'm especially nervous about complex electrical/computer challenges.

I really want my cobra to be very street friendly, but with a bit of excess grunt when needed or to make those club days a lot of fun!

I definitely want a manual and was thinking of the T56.

I have been very kindly assisted by Bobby (Plums) over here in Perth and I see 3 LS options so far:

1. Standard LS1
2. Standard LS76
3. LS76 converted to use LS1 computer/wiring.

My initial thoughts were to go for a standard LS1, but am now thinking of a LS76 but converting the crank (have I got that right?) to use the LS1 computer to keep the electrical/computing side of things simpler...

Any 1st hand experiences or learnings would be greatly appreciated.

Regards.......Paul

[Tenrocca]

Paul -

I would see little advantge in changing the L76 to run LS1 computer in a new install. A few guys have done it here, and from what I have seen, it is not as straightforward as installing it to run the normal standard L76 ECU with fly by wire throttle.

The L76 with a cam and valve springs can get very impressive numbers (ie. 300 rwkw), and for a crate engine Ive seen advertise for as little as $4000 - it has to be the performance bargain of the millenium. Yes there are a lot of add ons to get above the engine (loom\computer,alternator etc etc) but even with that it works out great value. As youve probably seen, there are a lot of places offering engine\gearbox\addons packages - and haggle. ONnce you get all that, youll still need to get your harness reworked (Sideshow can do that) and your ecu programed and then you should be off and running.

Cheers

[Beejay]

I would still consider a second hand package, you can get some good deals.

I know someone who is about to purchase a 6L and 6 speed from a wrecked VE with 4000KM. Complete with all accessories, airbox, exhaust, computer and full wiring harness for $10K.

Sounds good to me.

Ben

[Plums]

From a tuning perspective, running the LS1 PCM is a far better option. The older PCM is so much more adjustable and has the "nice features" that aren't available on the newer models.

I think it's six of one, half a dozen of the other.

The LS1 PCM and wiring is much cheaper than the newer stuff and to conect to an L76 is very easy, (just a few loom extensions), BUT you do have to change the reluctor wheel.

The newer wiring is a bit more of a hassle because you need part of the body loom to get the thing running which then has to be modified by someone, (which again adds more expense), BUT you don't have to modify the engine.

If it was me (and I will probably do it down the track too), I would fit the L76 with the older PCM and wiring.

The drag racer in me says: "if you have to take the crank out you might as well put a big arm in there and get 402 cubes".....

[pneall]

Paul,

I had an LS1 and have just converted to an L76 using the LS1 PCM.

While the motor is cheap the conversion is not as you need reluctor, relocate knock sensors, fit mechanical TB, new followers , new cam, bolts, under driven pulley. You end up equalling the purchase price in modifications....but its the cheapest HP you will ever buy.I am expecting around 320 RWKW plus greatly improved torque characteristics over the LS1 Time will tell as I am a few weeks away from firing it up.

If you are looking for a nice street set up either the LS1 or L76 will light up your day bigtime

There is a rumour that GM is about to off load the LS2 engines as the LS7 is being brought in as a replacement....now that (LS7) would make a great Cobra engine

Regards,

phil

[Rebel1]

Hey Uncle Phil, why are you so conservative with your L76 power expectations?.

You say you expect 320 RWHP with a cam.

It's almost common place for a cammed L76 to be around 380 - 400 RWHP, and that's with a relatively mild cam.

Keep in mind the tuners are unraveling the mysteries of the E38 and are now getting excellent results.

The LS7 sure would be nice but like Bobby said......a 402 ci L76 would be cheap by comparison and a lethal combination.

I am of the belief that the 5374 heads on the L76 will work much better with 400 cubes.

[pneall]

Uncle Les,

I am old and got my units mixed up...what I am expecting is 320rwkw

Phil

[Rebel1]

Bluddy hell

Thank gawd it's friday.

Just as well you got it right uncle Phil or I would have had to deal with ya severely.

Now, get to work and get that thing goin. You're the first I know who upgrading from an Ls1 and I'm keen to hear your impressions.

[alffie]

Ive had no problems with my LS7 and E38 ECU, cost $A440 to have it tuned for the cobra and mafless tune added 50 more HP! GM make the engine harness complete and the body computer plugs in to the ECU harness. Holden dont they have the body harness plug in to the engine aswell as the engine harness. The GM harness are cheap and simple everything plugs into the ECU and you will only have a few plugs out of the ECU for gauges etc.
Why dont you get an LSX 427? They dont have the dry sump and you can run what ever crank you want.
The Tremecs are about the only choices you have. Id go for the T56 with the 31 spline main shaft out of the viper. around $A5000 brand new.

[alffie]

Why do you want to convert the L76 to the LS1 ECU?

[alffie]

Also if your engineer picks up that you have changed the engine managment system he might not be happy with the emissions side of things.

[Plums]

While it's true that they are getting great results with the E38, it doesn't tell the whole story. The E38 is missing some of the great functions that were available with the older PCM's. E.G. Lean Cruise doesn't exsist in the E38 due to the stricter emissions requirements it must meet...
I'm pretty sure no engineer would pick the change.

I'm pretty sure you don't need to change the cam in an L76 to run the LS1 PCM. If you do change the cam you need to change the lifters I believe.

Rebel is right, the L76/L92 heads would be right at home with over 400 cubes, and when combined with a tasty cam and valvetrain should see around 350 rwkW's with awesome grunt down low.....

[alffie]

Why would you need to change the lifters? Arnt they rollers? The new LS3 heads are the best for a 4inch bore Ive been told.

[Rebel1]

Originally Posted by Plums

Rebel is right, the L76/L92 heads would be right at home with over 400 cubes, and when combined with a tasty cam and valvetrain should see around 350 rwkW's with awesome grunt down low.....

Now I gotta get my calculator out...........again.

[sideshow]

l76 with ls1 ecu is not so straight forward
just been doin heaps of research
mind u its easier than buying s crate motor l76
if u buy a crate motor from holden for say 4500 to 5000
then u wanted to buy the missing bits from a holden spare parts
u will spend another 4g getting the rest of the parts
trust me ive been thru it all for my customers

sourcing parts elsewhere might be cheaperl76 with ls1 ecu is cheap if u have
a spare ls1 starter o2 sensors

i have 2nd hand ls1 wiring looms and ecus and can easily be modded to suit the l76

but its around 500 to get reluctor ring on crank changed

then your forgetting the throttle body

l76 is fly by wire ls1 can be either

l76 is 90 mm ls1 is 75mm

so it means u have to run a cable ls1 ecu setup
and u have to buy a 90mm cable throttle body for best performance

untill people out there do the conversion they do not know completely what is involved

so it depends what parts u start with

if u have nothing i would go for the complete l76 engine and wiring etc
much newer etc

i think the reason they cannot tune the ecu as much is maybe the software is still only new
not sure i might be wrong

anyway i think if u buy a whole set from the same car u will have less hassles

i have guys buying crate motors from usa then buying ecus from holden in australia and they are not compatable

there are afew minor differences and there are afew more problems
you can run into

so buying complete set can save you afew hairs on your head

[acecob]

ford Power !!!!!!!!!!!!!

Dont compromise

[VintageUpgrades]

Paul, I don't know if you are still in the states or not, but the Porsche blue car arrives today.

[Tenrocca]

Originally Posted by acecob

CHEV Power !!!!!!!!!!!!!

Dont compromise

Fixed it for you Pete.

[427SnakeSC]

Originally Posted by acecob
CHEV Power !!!!!!!!!!!!!

Dont compromise

Hey I thought there were some four letter words, that we were not allowed to use here!

[Heidelberg]

Thanks everyone for your comments so far...I really appreciate the willingness to share your experience and knowledge...I'd also welcome comments from anyone who has installed a L76 with all standard L76 ECU/wiring loom?

As per my original thread, I'm trying to balance a very good performance engine, with great street manners and at the same time keep the install as simple as possible and I've heard from a number of sources the LS1 ECU/wiring is heaps easier than the L76...It also looks like there's a number of people on this forum either doing the conversion from LS1 to L76 or contemplating it...To my inexperienced eye, I can see 2 reasons for this...because it makes a lot of sense for someone who's alreay got a LS1 and it's a very logical performance improvement over the standard LS1 set up or it's just a good idea from a tuning/simplicity perspective to have the L76 mechanicals and LS1 controls/electricals?

I definitely want new gear and as I'll get the roller in '08, I suppose the newer GM L76 does have appeal...I don't know anything about the LS2 or LS7 options?

Phil...Starting from scratch...would you prefer the L76 with LS1 ECU/wiring options or a pure L76 install?

Sideshow, it seems you'd lean towards the standard complete L76 rather than try to use the LS1?

Thanks again for your comments...

Regards......Paul