Generation IV Internal Engine - lq9 408 stroker questions




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93cobra670
09-26-2009, 10:24 AM
I have a couple of quick questions regarding using an lq9 block in building a 408 stroker. I'm new to building gm's so bear with me haha.

1. can i use an ls1 crank in the lq9?
2. what size piston should i use if i were to go with ls2 heads and a t-rex cam?


thanks!


LS1TA385
09-26-2009, 03:44 PM
Someone correct me if im wrong but you can use the LS1 crank in the LQ9 just make sure you have the correct reluctor for the crank sensor. As for piston size for your 408 you would go with 4.030" of your choice.

DVS99TRANS
09-26-2009, 04:16 PM
^^^ sounds right, from what i have researched. But I would go move to a stroker crank on a 408 though personally. 4.030 with a -2cc (<<<minimal, pending your setup) whatever piston company you go with and you'll have more than enough room. Plus you can have alot of clearance later if you plan on swapping to a better set of heads.


93cobra670
09-26-2009, 04:54 PM
i'm leaning towards a high compression ratio because its most likely going to be a naturally aspirated car. Should i got with a 2cc flat top piston?

also, with the reluctor, can i just steal one off another car? as in use and ls1, ls2, or lq9 sensor?

i've built a handful of fords and the gm's are already a lot different haha

DVS99TRANS
09-26-2009, 05:36 PM
Depends on what PCM your using. If you have an LS1 (2004-earlier)PCM= 24xtooth. If LS2, it's 58xtooth. I do know that they are pressed on, if you can get one off intact I don't see why it can't be reused. I would go with a new one though to be safe. I have -2cc flat wisecos in my 408, static cr is 11.1-1. With a set of PRC 2. 5.3 heads undecked, compression sits about 11.5-1 for me, if that is the range you are looking for.

Gen414
09-26-2009, 07:40 PM
Well, if you decide to go stroker route, your crank (more than liklely) will already have teh reluctor wheel on. You just need to tell them which wheel you want.
My first LS based motor build I did, I went with a Eagle crank, and they asked me which wheel, told them 24, and wheel already on when it came.

Now, all of our builds, we use Callies Cranks, and they come with teh wheel. We ask which one you want (24 or 58).

Don't even think about pulling one off another crank...all you are gonna do is damage it, and again, no point anyways, as it will be on there with teh new crank.

To your original question, yes you can use a LS1 crank in a 6.0 truck block. BUT, you are not gonna build a 408 with a LS 1 crank.
To build a 408 with a truck block, you are gonna need a 4.00 crank (LS1 is 3.622), and you ask what size piston...well, with a 4.00" crank you are gonna need a 4.030" piston to get 408".

Jason 98 TA
10-01-2009, 05:06 PM
Definitely look at our short-blocks @

http://www.texas-speed.com/shop/categoryM.asp?MID=1&catid=28

We build complete short-blocks already assembled with the 4"stroke crank & we can set it up with your choice of reluctor wheel. TSP short-blocks now use Callies crank/rods & Wiseco pistons!! :) :)

If you decide to build one yourself we also offer complete rotating assemblies that can even be pre-balanced before they ship to you!