SVT THIS

iTrader: (27)

I plan on building up the 346 till she goes and then swapping in a 408 iron block. I would like to build my car with parts that would work well with the 408. I plan on a 90/90 setup and a great set of heads. I was liking the way the ETP 245s perform in the 408. Would it be to much overkill in a 346 if I run a huge cam (Trex or larger) and a 90/90 intake? Would the ETP 225s be a better choice? I know they would work well in the 346 but am not sure if it would be enough for a 408. I'd like to put in an order so I can have them by next summer

JZ'sTA

iTrader: (23)

The 245's will work, I would suggest the 225's or 215's for a 346 NA setup but the 245's will work.

beardWS6

iTrader: (1)

I have 245`s and they flow there *** off. The 90/90 setup I have doesn`t keep up. these heads flow really we`ll. I`m planning a sheetmetal or something else in the future. Just waiting to see what ET comes up with. But the TRQ these heads make on my motor is awsome!!! Check Sig!

SVT THIS

iTrader: (27)

I know they work great on 40x c.i. motors-#'s look great beardws6! Does anyone know what it might look like on a 346-I will most likely be driving it for 6months to a year while I build the motor. Would they be best if I left them uninstalled until the motor was done or would I still see some benefit if I ran them?

98NBMZ

iTrader: (6)

You would see a significant benefit as long as they are matched well with your cam. You won't see the potential of the heads or cam without a tune though.

Psycho Dave

I dont know all of the theory and ideas of an ls1....but on a gen 1 sbc, those heads would be huge on a 350....to even have a chance of being anything but a torque-less pig you would need big compression, big cam, big rpm, and big gears.....It could be total oppisite in the ls1 world but i doubt its that much different.

I think of it this way....your 408 cid motor would be a lot happier with stock heads than your 350 with huge heads.....use the money you have now to spend on the heads and get your bigger motor going...If you think about it ls1 heads are pretty decent compared to what some of the gen 1 guys are used to having and they still make 400ci motors work.

beardWS6

iTrader: (1)

Sorry, what I was trying to say earlier. My 408 still has alot left with these heads. Your 346 will not even begin to touch what they will do. You might not even get the power you want out of the 346 because of this. BUT for the future build it would be worth the short term loss. If you where going to stay 346 or even 383 etc I would go with the 225`s. But, since the 408 is your goal. Get a set of 245`s. But your right, you will need a BIG came, good exhaust, on the 346 to get something out of it. Let us know how it goes. But like I said, your 90 set will not be enough in the future for the heads. Good Luck!

Beast96Z

iTrader: (21)

Order the heads set up for the 4.030" bore, and I would prefer to sit on them till the motor is done. I believe it would make for a slouch in a 346. You have small cubes, lots of port volume, and a intake that can't keep up, which would equal low port velocities and less tq/hp. FWIW, the 225's may out perform the 245's on a 408 since the intake is better matched to the range of the heads. If you plan to stay with the FAST 90/90 on the 408, you may be better off with the 225's. If you plan on a big intake, then get the 245's.