Decided on engine

[Dr Peter]

After a lot of thinking
I’ve decided to go for a Chevy engine in the car, but I really, really wanted turbo’s.
And I think I can just bolt on twin turbo chargers.
I know next to stuff all about V8’s.
So can any one offer any help as I’ve seen a few people who have done this.

I don’t want all out and out power 400-500 BHP will be fine.
I’d rather have a standard engine with ARP bolts and just use the Turbo’s to get the power up.

What do I need and what / where is the best kit to get.
Turbo sizes, incoolers, etc etc
What have people done to help cooling?
Where is the best place to mount the turbo’s?
Do I need an ECU to control it all?

As I understand it I’m going to need a 350 block with a 400 crank, but that is about as much I know at the moment.

Any advice would be great

Peter

[craig-ultima]

I'm not an expert - but if you are aiming in the 400 to 500 hp range you can get that easily from a non-forced induction engine (carb or EFI). Much simpler and probably cheaper and more reliable.

The guys who pack turbos are using them to get crank power figures in the 700 to 1200 hp range.

[CanAm Dave]

Hi Peter

As Craig says to get 400-500BHP you are better off saying with a normally aspirated engine. The engine bays on these cars get hot enough without adding turbos. For the extra cost of adding turbos and the complexity of the build, and for that level of power, I'm not sure it would be worth it. Adding a supercharger would be easier and a lot less complex. Although not one like mine as its given me enough headaches. A Magnacharger like Crafty has would be much more simple to install. But each to there own.

Regards Dave

www.v8yes.co.uk

[eliot]

Not in an Ultima sadly, but Ive done a low boost twin turbo setup on a stock chevy - a very satisfying project. Click on my profile to find out more. I will also be at stoneleigh on sunday if you want to see it in person.

[ls2ultima]

Hi Peter

If you will be happy with 450 to 500 gee gees it would be much easier to just use a LS2 (or variant) as they come out of the box with 400HP and you can get another 100hp just by looking at them sideways.

[G Man]

This subject bores me just a little but you will have 2 problems with a turbo install, heat !!
400-500 bhp is easy to get out of a SBC, with instant throttle response and pickup if you want turbo lag buy an Impreza Turbo.
Problem 2 who will buy you car afterwards, its non-standard to the factory, and will depreciate like a free falling paracutist without a shoot.

There is no substitute for cubes and if you have them in an SBC why turbo it unless you want mad power it makes no sense

[andygtt]

twin turbo is the route I am taking for my mid engine project, but to do it in an ultima with a 6.3 SBC to get 450-500bhp is madness.

IMO things that will mean it's not as good as an n/a SBC with 500bhp are:
- Heat
- stock rev range
- weight
- cost
- complexity
- cooling
- did I mention heat?

I know turbo lag wont exist in a car this light (and such a large engine) and the sound the engine will make would be awsome, but will it really be worth it unless you are going for mad power?

[eliot]

I would agree that doing a low-boost turbo setup on an ultima wouldn't be worth the hasle, if your'e going to turbo it - shoot for a much higher number (600++). The bootfull of torque suits my heavy 4x4 - it's like dropping a 440 big block in without the weight, but I dont think it's as important in a lightweight ultima - as Gman has amply demonstrated.

[tuxman]

got to agree with everyone no point in turbo's go for a N/A 350 or 383 with EFI will make 400+ easy and drive smoooooooooth .simon

[crafty]

ls2ultima said:

... and you can get another 100hp just by looking at them sideways.

Naaah Bob....stare it in the eyes and slap it with your wallet! You'll get a couple of hundred out of the lil' bugger

[gtr-tt]

Since I have built a twin turbo Ultima I think I have a good idea about the challenges you will have. Let me tell you, DONT GO THIS WAY FOR 500 BHP. It's simply not worth all the extra work and money.

[Dr Peter]

“Problem 2 who will buy you car afterwards, its non-standard to the factory, and will depreciate like a free falling parachutist without a shoot.”

I’m not really bothered about this, I know how easy it is to plough money in to a build and your never get it back when you sell it.

Normal I would build something then every year in the winter upgrade some parts.
I don’t want to do that on this build, I’m in no rush to have the car finished, so what ever I do stays done.

I thought about the LSx engine, maybe see if I can find a LS6
But I know what I am like I'll want a Turbo after a while.

I said I was not fussed about the over all power of the car, of course the more the better, but I'd be quite happy with a low boost range and a grossly under stressed engine.

I loved my Impreza BTW

The only thing holding me back is the Heat issue, if it is really that bad I guess it will be no Turbo.

[ls2ultima]

I reckon that in the future LSX engined Ultimas will have superior resale than a SBC in almost all cases.
All the car nuts that we hang around with in Oz just cant believe that these cars are being constructed with
such old technology as the SBC in other coutries around the world.
I had a LS2 powered SS ute last year for my work transport and all we did was -
Headers, high flow cats, cold induction and chipset. No internals were altered.
That got us 500 HP. The car was still so well behaved that my 73 year old mum could drive it (and she did)
Try doing that with a SBC

[G Man]

I think the only reason that LS engines Ultimas are not popular in th UK is simply the stupid laws around Catalyst Conv on newer engines, personnally the only LS engine under the present rules and reg that would interest me would be the LS7 a factory crate engine with incredible parts at a cheap price that, makes the investment in a exhaust manifold, cat and back box special an easy one

[chuntington101]

you could allways, and i know im going to get slated for this, use a cossy engine!!!

these are fairly tunable to about 400 bhp but they can be a bit laggy! or you could us the 2.5ltr scooby engine! less laggy and bit more torquy!

or you could go for something even more radical like a nissan or mitsubishi V6 twin turbo or even an alfa V6 and get that twin turboed! there is a guy in south affrica i think that makes twin turbo kits for the alfas!

i think people get to fully about using other than standard engine! dont forget that the Ultima is a kit car so yourengine choice realy is down to you as it is in any kitcar!

just my thoughts!

thanks Chris.

[eliot]

G Man said:

I think the only reason that LS engines Ultimas are not popular in th UK is simply the stupid laws around Catalyst Conv on newer engines, personnally the only LS engine under the present rules and reg that would interest me would be the LS7 a factory crate engine with incredible parts at a cheap price that, makes the investment in a exhaust manifold, cat and back box special an easy one

As i understand it, there's nothing stopping you swapping the engine over AFTER the thing that you know i'm talking about

There's a guy with a LSx in a westfield who's done that isn't there?

>> Edited by eliot on Sunday 23 April 12:03

[crafty]

Im still at a complete loss as to what the problem is having a cat on your car when:

a. You only lose a couple of HP with freeflows
b. The car will smell like a bad fart without one.

[andygtt]

because cats produce heat in the already hot engine bay.

[Boosted LS1]

Dr Peter, I have a twin turbo lsx engine here, the specs may be right up your street. I have cast some custom exhaust headers (compact) and done a custom build of the engine. I've produced some custom chargecoolers (copper) and replaced the stock water pump. We can chat off line if you like.

Boosted.

[stig]

andygtt said:

because cats produce heat in the already hot engine bay.

Different aural experience with no cats too. Far more visceral without.