ls1 to a 408 or just heads and cam?
01-11-2010, 09:49 AM
#1
ls1 to a 408 or just heads and cam? i want a serious HP boost but don't think it is worth the money for LS1 heads and cam when the LS2 already dominates the LS1 with its 4" bore. i was thinking of getting an LS2 block, bore it over .060 and stroke it to 4" then i would have a 408. is this practical or am completely underestimating a heads and cam LS1?
01-11-2010, 10:28 AM
#4
It depends on your power goals.
If you want a fun st car, a Heads/Cam/Intake w full exhaust and gears is what you need.
If you really just wana take people's money/put bolt on cars to shame, do a 408 with a iron block.
It 'll still leave you in good position to do the trans, rear end if you go the lq9 over the ls2 way.
If you want a fun st car, a Heads/Cam/Intake w full exhaust and gears is what you need.
If you really just wana take people's money/put bolt on cars to shame, do a 408 with a iron block.
It 'll still leave you in good position to do the trans, rear end if you go the lq9 over the ls2 way.
01-11-2010, 10:35 AM
#5
The LS2 block is aluminum and will not allow a .060" overbore. An LS2 with a 4" crank would be a 402.
The heads and cam route if done right is more cost effective than the stroker, which is why it's so popular. Remember, with the stroker you have to buy both the top and bottom ends (and additional labor) while the heads/cam LS1 route you just need the top end.
The heads and cam route if done right is more cost effective than the stroker, which is why it's so popular. Remember, with the stroker you have to buy both the top and bottom ends (and additional labor) while the heads/cam LS1 route you just need the top end.
01-11-2010, 10:44 AM
#6
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Yeah I dont understand the whole overboring thing. Geez, these arent SBCs. Its like sanding your clear coat. You can only do it so many times before your clear coat isnt there any more. Well its just like that except its a MOTOR 
01-11-2010, 12:09 PM
#7
You can do a 6.0 iron block 408 and re-use your current engine covers where if you go to an LS2 you will need a conversion kit. As stated above the cubic inches are off as well.
As far as the h/c or 408 argument..bigger is better in a few ways.
Power.. bigger engines make more power
rpms... bigger engines take less rpms to make more power
streetable... bigger engines are more streetable when making more power
You need to run a bigger cam and rpm to make the same power you can make with a bigger engine. Bigger cam = less streetable, more rpm= big dollars and less reliable just by the nature of it.
But it really comes down to budget. You could stroke your ls1 to a 383 put a good top end on it and be at 450/500 for less money than a 408 but more than a h/c package.
As far as the h/c or 408 argument..bigger is better in a few ways.
Power.. bigger engines make more power
rpms... bigger engines take less rpms to make more power
streetable... bigger engines are more streetable when making more power
You need to run a bigger cam and rpm to make the same power you can make with a bigger engine. Bigger cam = less streetable, more rpm= big dollars and less reliable just by the nature of it.
But it really comes down to budget. You could stroke your ls1 to a 383 put a good top end on it and be at 450/500 for less money than a 408 but more than a h/c package.
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01-11-2010, 12:18 PM
#8
i was looking at the Trick Flow gen X heads with 59cc chambers, 225 intake runners, 2.02 intake and 1.60 exhaust valves. it will bring the compression to 11.1-1. they have a pretty good rep. i was gonna mate them with the FMS F13 cam .230/.232 @ .050. if i went with heads and cam. i already have QTP race version long tubes with the 4" y-pipe and SLP loudmouth out back. it is quite loud, i am considering a quieter muffler.
01-11-2010, 12:24 PM
#9
On a 346 cid?
You might want to re-think that unless this is a dedicated strip car? Do some reading about velocity and air speed. Take the time to educate yourself before you buy a cam and head. Big intake runners and a big cam doesnt make for the best combination on a 346 for the streets.
You might want to re-think that unless this is a dedicated strip car? Do some reading about velocity and air speed. Take the time to educate yourself before you buy a cam and head. Big intake runners and a big cam doesnt make for the best combination on a 346 for the streets.
01-11-2010, 05:54 PM
#10
TECH Resident
more info is needed to give accurate advice but lets just say your shootin for a fast street car. (460+ hp)
I would go with a h/c/i on a 346. A lot of people have found great success as well as longevity out of these set-ups. As well as it is a cheeper solution. As a bit of icing on the cake the money u save over doing a 408 you can put in a 9 inch or built tranny.
I would go with a h/c/i on a 346. A lot of people have found great success as well as longevity out of these set-ups. As well as it is a cheeper solution. As a bit of icing on the cake the money u save over doing a 408 you can put in a 9 inch or built tranny.
01-11-2010, 06:31 PM
#11
It all depends on budget. If you have the $ to build a big cube lsx do it. If you don't want ot spend a bunch of $ get a nice H/C package that you could transfer the heads to the new block when you blow the 346. It is not hard to make good power with a 346 but is 450-490rwhp going to do it for you, if not put 150 shot on top until the bitch goes and then buy the sort block you want. It's all what kind of $ you want ot spend.
