New best
11-03-2020, 06:41 AM
#21
As Tusky already knows I have a 406 bottom end ready to go in my car but I'm scared to change it. I'm afraid it won't be as fast ,not because it won't make a little more power and a lot more torque but because I may have to change everything on the car ,start over .
Last edited by zzracer; 11-03-2020 at 06:48 AM.
The following users liked this post:
fastsspr (05-16-2022)
11-03-2020, 11:26 PM
#24
Im going to try some travel limiters of some sort. I would like to try some better front coilovers but they are expensive. Better DA probably not going to happen. Tracks around here will be closed soon unless we see some warm days. If I happen to get a chance to run in better weather I'll try for sure. I had 3/4 tank of gas on those runs so I could lose a little weight there
11-10-2020, 05:56 PM
#26
Ls2 sbe, ported /shaved 799 heads, 236/242 cam, fast 102, 1 7/8 texas speed long tubes , custom y pipe with flowmaster 3" to 4 merge with a 4" bullet muffler. Performabuilt 60e, yank or 4000 converter. 8.8 hybrid rearend with 4.11 gears on 28" et streets, vikings on all 4 corners, bmr extreme arb. I ported the heads and done all the work and Joncr96z does the tuning. 3400 plus Race weight yesterday scales were closed so don't know exactly. Thanks
So the je pistons i bought are dished, but a little too much and i only end up at around 10.9-11.0:1 cr (same as stock ls2) and i'm now worried the lower CR might kill it too much with the cam i'm using which is a 243/250 .661/.652 108lsa with 30deg overlap. I didn't want to go bigger on the cam to lower the dcr as i still drive it on the street, and being that it's only a 6.0, i think the cam i'm using is already borderline.
I can go to a thinner 0.040 cometic and gain a little, but i'm just not confident in those head gaskets versus the gm mls and i don't really want to mill the heads either. I guess i will just have to run it as is and see what happens. Anyway that's why i was just wondering what your CR is. I'm guessing it has to be at least high 11's CR with milled 799's.
Last edited by Launch; 11-10-2020 at 06:14 PM.
11-10-2020, 07:07 PM
#28
Launch I'm around 11-1 by my figures. My heads are shaved but I opened the chambers up to unshroud the valves. Between opening the chambers back up and the valve reliefs I cut in the pistons I didn't really gain much from shaving the heads. I am also running a .051 stock gasket. I think that cam you have picked out is going to be too big for a 6.0 unless you put a lot more compression in it. That's my opinion anyway.
11-10-2020, 08:33 PM
#29
Thanks. Even more impressive given you are still at around only 11:1 cr. You have the whole combination working very well.
I didn't pick this cam it just came available and i bought it thinking i can use it something. I know it's a bit on the big side for a 6.0, but i've decided i'm going to try it first up, and if it doesn't work well i will remove it and fit something else.
It was a pain to get the CR i want all the shelf pistons, with the heads i have. I didn't want to custom order pistons but in hindsight i should have. The only good thing is i won't have to worry about pump gas not being good enough. Also i should be able to keep some good timing advance in it, which should help in theory.
Anyway, back to your car. I always like seeing people getting the most out of sbe. And the sbe's can sure take a beating more than most of us ever imagined. I even bought good aftermarket rods for my 6.0 that i'm building and i was going to use them, but i've now decided to stick with the stock gen4 rods in it this time around. After seeing what i've put my current gen3 5.7 through and it still won't die. I already had the je 6.0 pistons to suit stock rods also. I'll keep the other 6.125 rods i have, in case i ever need to use them.
I didn't pick this cam it just came available and i bought it thinking i can use it something. I know it's a bit on the big side for a 6.0, but i've decided i'm going to try it first up, and if it doesn't work well i will remove it and fit something else.
It was a pain to get the CR i want all the shelf pistons, with the heads i have. I didn't want to custom order pistons but in hindsight i should have. The only good thing is i won't have to worry about pump gas not being good enough. Also i should be able to keep some good timing advance in it, which should help in theory.
Anyway, back to your car. I always like seeing people getting the most out of sbe. And the sbe's can sure take a beating more than most of us ever imagined. I even bought good aftermarket rods for my 6.0 that i'm building and i was going to use them, but i've now decided to stick with the stock gen4 rods in it this time around. After seeing what i've put my current gen3 5.7 through and it still won't die. I already had the je 6.0 pistons to suit stock rods also. I'll keep the other 6.125 rods i have, in case i ever need to use them.
11-10-2020, 08:42 PM
#30
I may try to bump the compression on mine a little to take advantage of e85. Yeah if you got the cam won't cost you anything to try it. If you can bump the compression with that cam it will definitely help. Good luck and keep me posted on how it does.
11-10-2020, 09:31 PM
#31
Higher CR and e85 will help for sure. I think you can gain more even just going to around 11.6:1 cr ( probably still being able to run 93 octane), and going any higher CR and e85 will gain some more, just depends if you are after every last tenth of et or want a compromise and still run 93.
I will think more about milling my heads. They are somewhat rare ecr nascar small bore ls7's, even if it's just in my head only, it kind of puts me off milling them. If i try it as is, if it doesn't work, i can change things around then. I haven't had enough experience personally with bigger cams in 6.0 ls's, and around 11:1 cr only.. i really don't know how it will work until i try it. In my mind a 243/250 with 30deg overlap is big, but not that huge, but maybe i'm totally wrong and it'll be a slug with 11:1 cr. Yours is working very well for what it is, with a bit smaller cam than i have.
I will keep you posted.
I will think more about milling my heads. They are somewhat rare ecr nascar small bore ls7's, even if it's just in my head only, it kind of puts me off milling them. If i try it as is, if it doesn't work, i can change things around then. I haven't had enough experience personally with bigger cams in 6.0 ls's, and around 11:1 cr only.. i really don't know how it will work until i try it. In my mind a 243/250 with 30deg overlap is big, but not that huge, but maybe i'm totally wrong and it'll be a slug with 11:1 cr. Yours is working very well for what it is, with a bit smaller cam than i have.
I will keep you posted.
11-10-2020, 09:58 PM
#33
I didn't realize you were already on e85. In that case bumping cr should do even more.
My valves are 2.10 / 1.55, and all titanium (which won't really gain any HP being lighter than stainless, except can use less spring pressure for longevity of springs/lifters)
I bought the heads as they are. I have no idea what they flow but they look impressive. If they work even just as good as a very good cathedral head, i'll be happy. Any more will be a bonus.
My valves are 2.10 / 1.55, and all titanium (which won't really gain any HP being lighter than stainless, except can use less spring pressure for longevity of springs/lifters)
I bought the heads as they are. I have no idea what they flow but they look impressive. If they work even just as good as a very good cathedral head, i'll be happy. Any more will be a bonus.