LSX 454

Author
Discussion

chuntington101

5,733 posts

235 months

Wednesday 28th October 2015
quotequote all
LSX Fan, what intake manifold do you plan on running? From what I have seen this is the limiting factor on many big cube LS builds. There seems to be deminising returns using stock style intakes past about 650bhp. Even the big 502 inch ERL superdeck 2s (no longer in production) had trouble making over this.

Might be wroth looking at a carb type intake also. You will loose some torque down low but you should have plenty of torque with 454 inches to play with.

Also what heads do you plan on running and are you going 4 or 6 bolt block?

LSX Fan

33 posts

146 months

Wednesday 28th October 2015
quotequote all
chuntington101 said:
LSX Fan, what intake manifold do you plan on running? From what I have seen this is the limiting factor on many big cube LS builds. There seems to be deminising returns using stock style intakes past about 650bhp. Even the big 502 inch ERL superdeck 2s (no longer in production) had trouble making over this.

Might be wroth looking at a carb type intake also. You will loose some torque down low but you should have plenty of torque with 454 inches to play with.

Also what heads do you plan on running and are you going 4 or 6 bolt block?
LOL! Naw...no carbs here. I plan to use the LS7 intake. GM Performance makes a fuel injection kit for the LSX 454 that uses the LS7 intake manifold and appropriate sized injectors and calibrated ECU; it even includes the drive-by-wire setup. The heads on the LSX 454 are basically duplicates of the LS7...the difference is the LS7 has CNC 70cc ports and the LSX 454 has cast 70cc ports. I've priced the long-block and the injection kit, and combined they are under $13K US dollars.

http://www.jegs.com/i/Chevrolet-Performance/809/19...

chuntington101

5,733 posts

235 months

Wednesday 28th October 2015
quotequote all
LSX Fan said:
chuntington101 said:
LSX Fan, what intake manifold do you plan on running? From what I have seen this is the limiting factor on many big cube LS builds. There seems to be deminising returns using stock style intakes past about 650bhp. Even the big 502 inch ERL superdeck 2s (no longer in production) had trouble making over this.

Might be wroth looking at a carb type intake also. You will loose some torque down low but you should have plenty of torque with 454 inches to play with.

Also what heads do you plan on running and are you going 4 or 6 bolt block?
LOL! Naw...no carbs here. I plan to use the LS7 intake. GM Performance makes a fuel injection kit for the LSX 454 that uses the LS7 intake manifold and appropriate sized injectors and calibrated ECU; it even includes the drive-by-wire setup. The heads on the LSX 454 are basically duplicates of the LS7...the difference is the LS7 has CNC 70cc ports and the LSX 454 has cast 70cc ports. I've priced the long-block and the injection kit, and combined they are under $13K US dollars.

http://www.jegs.com/i/Chevrolet-Performance/809/19...
Note I said carb style intake, not a carb. Totally different thing! Lol

Are you sure that's the tall deck version? It looks to be running a 4.185 inch bore which is REALLY BIG for a LS engine.

R8VXF

6,788 posts

114 months

Wednesday 28th October 2015
quotequote all
Storer said:
Chap
I suspect from your garage you have no idea what an Ultima is like. I went from a Cerbera to the Ultima and there is no comparison.
One of the reasons you see so many low mileage Ultima's for sale is that they can scare the sh*t out of their owner.
I am well aware of the operation of a throttle pedal. yes

Bigger is not always better!


Paul
I know exactly what an Ultima is, thank you very much. I haven't fully filled out my garage, so do not make assumptions and make a complete asshat of yourself wink

LSX Fan

33 posts

146 months

Wednesday 28th October 2015
quotequote all
chuntington101 said:
Note I said carb style intake, not a carb. Totally different thing! Lol

Are you sure that's the tall deck version? It looks to be running a 4.185 inch bore which is REALLY BIG for a LS engine.
Oh...I'm sorry, I read that wrong. smile But no, I've decided to stick with the LS7 Intake, it keeps things simple and I'm not really trying to go beyond 600 HP anyway. As for deck-height, the LSX 454 has a standard deck, that's why the LS7 intake will fit. If it were the 9.7" (tall-deck) version, you'd have to use some sort of spacers to close the gap. The 454 does have much deeper sleeves than a standard LS block though, so the pistons don't come out of the bores during the down-stroke. Also, unlike a LS7, the 454 is designed with thick walls and can handle much larger bores than standard aluminum LS blocks.

EDIT: Oh, and one other cool thing about the LSX 454 is that it has 6 head bolts per cylinder, unlike the LS7 which has the standard 4. So it seals under pressure much better than other LS blocks.

Honestly, like many have stated before, 600 HP is more than enough for an Ultima. But at the same time I like options because you never know when the speed bug will bite you. And like the ole American phrase goes, "There's no replacement for displacement."

Edited by LSX Fan on Wednesday 28th October 08:58

deadscoob

2,263 posts

259 months

Wednesday 28th October 2015
quotequote all
R8VXF said:
I know exactly what an Ultima is, thank you very much. I haven't fully filled out my garage, so do not make assumptions and make a complete asshat of yourself wink
When I met Paul on a Bedford trackday I noticed he had concrete boots on wink

Being serious for a rare moment, when I first started my build, I was convinced I had to have 700hp. I ran out of funds and ended up with a "puny" standard LS7. Felt great, got used to it, tweaked it with a cam and a few other detail changes.

Had a few issues with the map, got it sorted and now have efilive for tweaking which I supplement with a vbox to validate any performance gains. I use a simple method for this, a 3rd gear roll on as it gives an easily repeatable set of data.
I genuinely cannot feel the difference, in a seat of the pants way, between 60-100 taking 3 seconds or 2.7 seconds.
10% difference seems like it should be noticeable, but it's not. Not to me anyway. So I guess I need more (without sticking the equivalent of a boat anchor on top of the engine).
Tis a slippery slopesmile

ROWDYRENAULT

1,270 posts

213 months

Wednesday 28th October 2015
quotequote all
great choice don't forgot the dry sump. lee

LSX Fan

33 posts

146 months

Wednesday 28th October 2015
quotequote all
ROWDYRENAULT said:
great choice don't forgot the dry sump. lee
Speaking of oiling systems. I know you're a big proponent of dry sumps for any racing application...but would you also advise someone to use a dry sump if the Ultima was going to be used strictly on the highways? I ask this because that's my intended use. I was suppose to have my Ultima ordered years ago, but life has a way of getting in the way. Now that things have settled, I want to build a daily-driver that will probably see absolutely no track use. Could I manage with a good stock-style setup, or should I budget for a dry sump regardless?

deadscoob

2,263 posts

259 months

Thursday 29th October 2015
quotequote all
Can't see why you'd need a dry sump if it's road only.

Racingroj

488 posts

162 months

Thursday 29th October 2015
quotequote all
Deadscoob, please see 13th post.

deadscoob

2,263 posts

259 months

Thursday 29th October 2015
quotequote all
Roj,

See the post above asking if you need one for road use only smile

Storer

5,024 posts

214 months

Thursday 29th October 2015
quotequote all
LSX Fan said:
ROWDYRENAULT said:
great choice don't forgot the dry sump. lee
Speaking of oiling systems. I know you're a big proponent of dry sumps for any racing application...but would you also advise someone to use a dry sump if the Ultima was going to be used strictly on the highways? I ask this because that's my intended use. I was suppose to have my Ultima ordered years ago, but life has a way of getting in the way. Now that things have settled, I want to build a daily-driver that will probably see absolutely no track use. Could I manage with a good stock-style setup, or should I budget for a dry sump regardless?
You may not plan to do a track day now, but an Ultima can only be really enjoyed on a big, open track.
It is also a great place to learn the limits of the car (and yourself).

If you are to do a daily driver then all you need is a standard LS3, no dry sump but add traction control.

The other thing you will need is your own East European on retention to clean it every other day or it will soon look rather 'second hand'.

But first, enjoy the build.


Paul

Racingroj

488 posts

162 months

Thursday 29th October 2015
quotequote all
Deadscoob
Sorry mate this retirement lark gets to you some days.

Pascal Mertens

Original Poster:

25 posts

114 months

Wednesday 2nd December 2015
quotequote all
Thanks for all the advice. I didn't go for the LSX !

It became a 615bhp LS3 uprated with comp cams, hi tech push rods and dual valve spring kit.

The Canadian builder delivers it with a handheld computer.