flipmike22

I got a ls2 bored and stroked to a 408.

Bore 4.03 stroke 4.0
Wiesco 6448RX3 pistons
Wiesco 6125 H beam connecting rods with arp bolts
Coyles dual hex adjustable timing chain
Melling high volume oil pump
Arp main studs

Now the top end I need help on opinions and recommendations.

This is what I ha planned(bare with me if things don't seem correct)
Custom l92 heads ported and polished
Stainless valves 2.16" intake 1.60" exhaust
Springs I'm thinks gold patriot duals(lmk if this will work with a cam lift of .670
Viton valve seals
Ti retainers
And the chamber I was thinking of 64cc instead of a 70cc(plan on running e85)
Intake runner is 280cc and exhaust is a 90cc

Anyone know where I can get a custom grind cam of .670 or higher haven't decided yet.

Need help on pushrods, head gasket, lifters, size fuel injectors and if the set up I listed seems ideal?

mark21742

I'm spinning my 408 to 8,000 rpms on 60lb injectors. I know some guys over on yellowbullet running cams pushing close to 1" lift.... Are you looking at getting longer valves too, or sticking with stock?
About what rpm range are looking for the most power, and what intake? (I run and love the Edelbrock proflo xt) My 255/271 .624/.624 115lsa is still pulling hard as hell at my 8,000 rpm fuel cut.

I'd also go Morel link bar lifters, no questions asked. .040" mls Headgasket, maybe a 4.080-4.125 gasket bore. It takes longer, but best thing to do is get the motor together, then check for pushrod length

PREDATOR-Z

LS2 bored to 4.030? Are you sure? That will be pretty thin for LS2, LS2 is like LS1, light hone for 402cid.

redtan

iTrader: (5)

Plenty of people have done it and it seems to hold up fine without boost.

LS2 liners are thicker than LS1 ones and are not limited to just a 0.010 hone.

ERL for example specifically sells LS2 based 408s, so if they can do it then I'll believe it.

flipmike22

Ya the block made an easy 750 flywheel hp on e85 my plan isn't that far off. But the gasket I plan on going is the note size mentioned about at a .04 and the heads I'm going with afr 230cc with a cam lift of .670 with a 114lsa and a 102mm ported out on maybe 130-160lb injectors. As far as head set up I need suggestions on rockers, springs, valves and all. The bottoms end is already set and is ready for an excellent setup up top to finish her. She'll be an n/a beast btw no boost here. In the future I do plan on swapping in itb's just for the hell of it. I know they're pricey but it's my choice...

mark21742

As for rockers, I'd do it once and do it right by jumping on the $1,500 Jesels.

Get who ever grinder your cam to recomend the correct valve springs, pressures and shims.

Harrop make a beautiful itb set up that makes some nice power while keeping decent streetablity...but $6,000 is a lot of coin to drop on them lol

flipmike22

Yes 6,000 is way too much. Ply I'm looking for the lower profile Cross itb's. so for the heads do you feel it's suitable for the set up? The guy is sellin me a 102mm fast I take with rails, #60 injectors, 102mm throttle body. Ev1-ev2 adapters, map extension, 4" maf. With the afr heads with the items I listed before for a solid 5200. I'm extremely debating about this but some of the parts I just don't need.

flipmike22

Could you explain the jesels rockers? Haven't heard much on them and they're price is ridiculous

Blackpanther99

iTrader: (8)

Thats a beautiful sound block you got there. L92s will work pretty good, as far as the cam goes dont hesitate on asking Martin @ Tick Performance for a cam recommendation, he will set you up good with size of cam and give you a good advise for rockers, lifters and all.

KingPin1094

iTrader: (12)

Im building a 408 as well that has the L92 heads. I had Pat G spec me a cam and am having EPS grind it for me.
-Im waiting to get my motor assembled then measure for pushrod length then order them.
-For the head gasket that depends on what CR you want. I am shooting for 11:1 CR so im using .060" MLS gasket
-And i got the street Lunati Link-bars which are relabled morel lifters.
-I have LS1 style 60lb injectors that i fitted on my LS3 intake

The 408 with LS3 top end is a very potent platform that can be capable of some very high hp and tq numbers.

garygnu

with stock GM heads use stock GM rockers ,with trunnion bearing upgrades.Pat-G ,Martin at Tick ,or several others spec good cams.can you rock block ls2 blocks like old sbc ?

flipmike22

Thanks or the info on who to go to as far as the cam specs.

And thanks blackpanther99

I think I'm set on the afr heads. I saw a review of them vs the l92's and showed a 20hp difference. I might just port them a bit more. It was either those heads or some l92 thompsons heads(being they're local a lot cheaper and can probably help me in the future). And I'm not using stock gm heads...

I'm planning on using some 130lb injectors to help with the e85 demand for fuel.

Can anyone throw a nice parts list for the 2 lhead listed below? Please bare with me v8 is not usually my specialty.

Aftermarket l82 Thompson heads
BIG STAINLESS VALVES 2.16" intake 1.60" exhaust
Dual valve springs good to .650" lift
Titanium retainers and chromoly spring locators
Custom TMS CNC port work on intake and exhaust runners
Viton high lift valve seals
Multi angle valve job

TMS head flow data in CFM found at 28 inches
lift intake exhaust
0.100 64 54
0.200 141 116
0.300 207 163
0.400 260 195
0.500 318 225
0.600 351 232
0.650 364 237
0.700 362 246

Intake runner size 280CC

Exhaust runner size is 90CC

Cnc ported

Or

Afr 230cc heads chamber at 72cc
Shimmed heads for some 1.7 yellow tella rockers
2.08 intake valves 1.6 exhaust
Rated at a .600 lift 328 intake to 252 exhaust

Now given that the custom l92 heads are showing bettor flow I feel maybe the afr's Wouk flow great after a port job? Now if I were to take into consideration about cost the afr's are hands down going to cost way more. Maybe 2k more after the port job.