v8 ls series engines...

RobMatthews · December 13, 2007, 07:32:54 PM

hi question for people into the v8\'s, been looing around a little bit on the net and find engine conversions(for fd3s) with ls1 or ls 2 or ls7 etc engine\'s in cars, so my question is what is the difference? is it just engine capacity or more than that? also difference between the shortblock and bigblock?
and while im here do you really need to uprate the rear subframe etc to handle the power of say a ls1 500 bhp engine, seeing as there are fd\'s out there running this sort of power through single tubs.thanks in advance for anybody who answers my questions:cheers

rx7veilside · December 13, 2007, 08:39:05 PM

the ls1 etc just relate to diff versions of a basically the same engine but the ls1 starts at arounf 350bhp/350 foot pounds later ones more power
talk to tinker27 hes done a few now
to my way of thinking a superb swap for the unreliable rotary and the sound is superb just need to make sure u use the right bits
loads of the yanks do this conversion

Spartacus · December 13, 2007, 08:52:17 PM

Blimey, where to start.......Well, very basically the LS1 is a 5.7L with around 350bhp and 350 lbs torque and a cable throttle, LS2 is a 6L with around 400BHP and 400lbs torque with flyby wire throttle LS7 is a 7L with around 500 BHP and 470lbs torque again with a flyby wire throttle.

You might be getting confused with the terms short and big block as a short block is most of the engine assembly without heads etc but the term big block is normally used for the old school American large displacement iron blocked engines, and not for what I\'m guessing you mean a full engine.

As for updated rear subframes this like so many other areas is open to conjecture but most people in the US who have done this conversion keep the rear subframe standard but instead of the Mazda PPF they use a torque arm. I would recommend having a look and search on v8rx7forum.com where all your questions and answers have been discussed many times.

Anything else I can help with drop me a line, but be warned I\'m no expert.

RobMatthews · December 16, 2007, 07:27:49 PM

so is there ls3, ls4 etc? these engines are the same as in the austrailian monaro\'s? i\'ve seen some out there now with twin turbo\'s making faily reliable 800bhp!

prince_of_tokyo · December 16, 2007, 07:51:30 PM

sorry i might seem a little oblivious to this guys, but wouldnt placing a v8 upfront make the car a little nose heavy considering the beauty of the 13b engine is that it is soo light considering power ouput? do the big v8s fit under the bay ok?

rx7veilside · December 16, 2007, 07:55:20 PM

no weight difference/no handling difference and ls1 fits in loads in america and a few over here now

johnf · December 16, 2007, 07:59:24 PM

Tinker27 put his LS1 Gen3 on four weight pads [each wheel] and the weight distribution was spot on.

I\'m sure he\'ll have an input when he picks this thread up.

John

Timmy · December 16, 2007, 08:03:28 PM

Are you thinking in realation to short block and big block. OF small block and big block chevy engines. Not good for a rx7 imo as i think they are cast iron and very heavy compared with the ls series engines.

Spartacus · December 16, 2007, 08:07:01 PM

Quote from: RobMatthewsso is there ls3, ls4 etc? these engines are the same as in the austrailian monaro\'s? i\'ve seen some out there now with twin turbo\'s making faily reliable 800bhp!

Here you go http://en.wikipedia.org/wiki/GM_LS_engine

Yes the engines are the same as Monaro\'s. The only problem re turbo\'s is the engine bay of the RX is alot smaller than the Monaro.

RobMatthews · December 16, 2007, 08:43:59 PM

yep thats def hit the spot cheers sparticus- i am s##t at doing searches!

tinker-27 · December 17, 2007, 07:05:13 PM

i make a conversion for the rear diff mount this is one of the most important part of the conversion,i get rid of the power frame completly,the diff is up to the job ive been running 550+ for a while through one. the ratio is more of a problem. as spartacus says look on v8rx7 ,but i will try to answer question if i can

interloper393 · December 17, 2007, 07:38:13 PM

so how much is a ls1 engine as this seems to be the best engine for the swop? id love to have a go in one to see what there like

tinker-27 · December 17, 2007, 09:52:11 PM

they start from Â£4000 for a decent engine and gearbox,anyone is welcome to a go in mine,but every one thats been it wants one !!!

rx7veilside · December 18, 2007, 07:33:20 AM

do u have a source for the engines and boxes..i will have to take a ride up and go out in one of these babies

Carl · December 18, 2007, 07:48:01 AM

Quote from: rx7veilsidethe ls1 etc just relate to diff versions of a basically the same engine but the ls1 starts at arounf 350bhp/350 foot pounds later ones more power
talk to tinker27 hes done a few now
to my way of thinking a superb swap for the unreliable rotary and the sound is superb just need to make sure u use the right bits
loads of the yanks do this conversion

Oh ye of little faith Paul!(The unreliable rotary engine)

Put some miles on that engine so we can show you how good it is! How many have you done now?and in how long?at the rate you are going it will last 50 years!

Seriously though the LS series of engines are a great swap actually,and I can say having been in Craigs car great fun! I don\'t decry anyone who does the conversion.

Regards
Carl