Discussion
Reporting further on the LS7 conversion project (red GTR):
Jeff Schwartz has finished the build and dynoed my LS7. Results are great: 564HP at 6.250rpm and 517 lb-ft (= 700Nm) at 4.750 rpm. This with std. internals, all accessories, air filter and cats! Without "correction factor", I should add.
The engine and all accessories will be soon shipped to our workshop. Jeff also matched my new GT2 gearbox (which is rated for 680Nm) to the LS7, i.e. built an adaptor/flywheel.
Cant wait to see it running!
Some pics:

Jeff Schwartz has finished the build and dynoed my LS7. Results are great: 564HP at 6.250rpm and 517 lb-ft (= 700Nm) at 4.750 rpm. This with std. internals, all accessories, air filter and cats! Without "correction factor", I should add.
The engine and all accessories will be soon shipped to our workshop. Jeff also matched my new GT2 gearbox (which is rated for 680Nm) to the LS7, i.e. built an adaptor/flywheel.
Cant wait to see it running!
Some pics:

deadscoob said:
Is this totally stock, no cam or head work?
Completely stock (internals). Of course a lot of work still needed to be done, eg. to flip intake manifold, several new fittings, a lot of accessories (alternator, A/C compressor, starter, plus adaptor for gearbox, dry sump tank, etc.).
Jeff told me that it would be no problem at all to get more power by changing some internals (cam, pistons), but I decided to try it first stock and to tune engine later in case that I find that I need more power
Not very likely, though, given that the engine package will be some 40kg lighter than my current one (Dart iron block).
Hugger Z said:
Congrats and nice numbers! We got to see your engine and transaxle when we toured Jeff's shop at the US Ultima gathering back in September. Looked nice then, but definitely good to see what it can do. Enjoy once you get it in the car!
Thanks!
Will try to do some videos once it is on the road, but this will take a while...
k wright said:
Stock is the way to go when you start with such a great motor. RE: the Z06 headers, take a closer look at them. They are not likely to offer much resistance to flow.
Ken
Ken
Agreed but maybe they don't assist flow either?
Long tubes always seem to help on the lsx variants or so people say and this bone stock engine is way up on power so why is that? The headers are an obvious answer. I quite like the GM hydroformed jobbies but it's interesting to note GM switched back to cast iron lumps after a short while on the ls6 once sales are established and costs become important.
They save money everywhere, you just have to look a bit more closely.
Boosted.
chuntington101 said:
boosted, din't they have troublw with them cracking to???? thought i heard something on it on one of the us forums.
Chris.
Chris.
I don't know Chris but the stainless hydroformed items must be quite expensive to produce. They're double skinned and there's lots of welding to.
Boosted.
Boosted LS1 said:
k wright said:
Stock is the way to go when you start with such a great motor. RE: the Z06 headers, take a closer look at them. They are not likely to offer much resistance to flow.
Ken
Ken
Agreed but maybe they don't assist flow either?
Long tubes always seem to help on the lsx variants or so people say and this bone stock engine is way up on power so why is that? The headers are an obvious answer. I quite like the GM hydroformed jobbies but it's interesting to note GM switched back to cast iron lumps after a short while on the ls6 once sales are established and costs become important.
They save money everywhere, you just have to look a bit more closely.
Boosted.
Jeff told me also that my engine made actually more power with cats (+10 HP)!
ultimacz said:
Boosted LS1 said:
k wright said:
Stock is the way to go when you start with such a great motor. RE: the Z06 headers, take a closer look at them. They are not likely to offer much resistance to flow.
Ken
Ken
Agreed but maybe they don't assist flow either?
Long tubes always seem to help on the lsx variants or so people say and this bone stock engine is way up on power so why is that? The headers are an obvious answer. I quite like the GM hydroformed jobbies but it's interesting to note GM switched back to cast iron lumps after a short while on the ls6 once sales are established and costs become important.
They save money everywhere, you just have to look a bit more closely.
Boosted.
Jeff told me also that my engine made actually more power with cats (+10 HP)!
I can well believe that and 10 hp is worth having. They'd effect back pressure, the headers would effect flow and scavenging. I was suggesting that the long tubes raised hp compared to the hydroformed headers because this is a bone stock engine that's making more power. Something must have got it to those figures so I'd guess at the headers. The US forums are full of cars with long tubes and the same from Oz. A few horsepower per cylinder on a v8 soon adds up and if they're good for 5 hp per cylinder, nice
Boosted.
p15ton said:
We have seen just short of 590bhp, out of the box LS7, nice exhaust, Motec, very good map. Cam & a few other changes make just under 650.
Wow, if thats true then its a great engine, even better then I thought, realy amazing!
combine that with a nice Ultima and you have great peformance and "reliabillity" en "ecomics"
Brings me back of the thought of that nice RCR-40 also made in the USA with that very nice alu chassis and that car could also have that LS7 engine...yummie
its like a work of art...I like it all that aluminum, sadly its in the USA "cheap" but when you bring that same car to the Netherlands its to pricy for me aaaaaaaaaaaahhh;
www.race-car-replicas.com/index.html
GTRene
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