Building a 408ci
Originally Posted by necrocannibal
We have talked about this before. You are running 13 to 1 compression, or some ungodly high number, on a strip only drag car. I am only running 11 to 1. Plus you have bigger headers and better intake and all. I am going to do a head swap to stage 3 heads and change nothing else and I will get back to you and let you know how much it changes.
I know we have. my compression is more like 12.3:1 and I'm running 1 3/4 headers. I just think your heads aren't the problem you think they are. by your statement, you current heads are BETTER than mine. that what I'm trying to point out.
looking forward to hearing your results
I would also love to put on my AFR 225's and see what mine does.
Originally Posted by 383ss
I know we have. my compression is more like 12.3:1 and I'm running 1 3/4 headers. I just think your heads aren't the problem you think they are. by your statement, you current heads are BETTER than mine. that what I'm trying to point out.
looking forward to hearing your results I would also love to put on my AFR 225's and see what mine does.
looking forward to hearing your results
I would also love to put on my AFR 225's and see what mine does.
i'd love to run a 402 aluminum block. not the huge weight gain the iron block is. as it stands right now i'm lookin @ a 383 until the price of the ls2 block comes down a bit.
Originally Posted by necrocannibal
I am just hoping that the heads are my problem. Its the next logical step so I am going to try it and see what happens. Hopefully it will jump it up, if not then I will try something else, or sell it.
Originally Posted by VINCE
Your #'s are low, but you have the wrong exhaust system. I would start with changing the exhaust first. Remember when you piece together stuff like your sig shows you did.. You get other than ultimate results.
Whats wrong with the exhaust system?? Besides needing bigger headers. The true duals are 3" all the way out throgh an X pipe.
Originally Posted by necrocannibal
Whats wrong with the exhaust system?? Besides needing bigger headers. The true duals are 3" all the way out throgh an X pipe.
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i just orderred a 408 eight from APE and they have a set of 6.0L race heads that flow tons.........they go for 2299.00, no core!! check da link
http://www.automotiveperformance.net/cylinderhead.htm
a big cam can be made streetable, like it was stated before, with the right tune...the real question is wat size cam is optimal for a 408. I've been researching and i still havent found a conclusion to what it may be. I can only see wat other guys are runing and compare. THe 408 iron is heavier but the security of the material is well worth the compensation. Also, i think you can go .060 on the iron if you wanted to go bigger.
The cam im installng is 244 248 .600 .600 114...its the same cam that mike k. is running (dude, if you dont mind me posting it...) and it has produced great numbers for his setup. Also, stage 3 heads with the 2.08/1.60 sizing will be a better match for the 408 since you need the added flow for the added cubes IMO.....also a 90mm intake, fuel system upgrade will make it all make optimal...........and if in doubt, you know you can spray the hell out of it (safely), possibly with progressive NOZ controller and have the peace of mind that the motor will hold!!
personally, dont go for something that u might not need.......i think that your cam is holding you back though...........do a cam swap and see wat happens........them go heads.you should be at 500rwhp........(question, those numbers were on a dynojet or mustang.....dynojet right?) im still not sure if going to a 17/8 header will make that much more of a difference but i would hold off until the intake is done IMO
enjoy and keep tuning...........LAterZ
http://www.automotiveperformance.net/cylinderhead.htm
a big cam can be made streetable, like it was stated before, with the right tune...the real question is wat size cam is optimal for a 408. I've been researching and i still havent found a conclusion to what it may be. I can only see wat other guys are runing and compare. THe 408 iron is heavier but the security of the material is well worth the compensation. Also, i think you can go .060 on the iron if you wanted to go bigger.
The cam im installng is 244 248 .600 .600 114...its the same cam that mike k. is running (dude, if you dont mind me posting it...) and it has produced great numbers for his setup. Also, stage 3 heads with the 2.08/1.60 sizing will be a better match for the 408 since you need the added flow for the added cubes IMO.....also a 90mm intake, fuel system upgrade will make it all make optimal...........and if in doubt, you know you can spray the hell out of it (safely), possibly with progressive NOZ controller and have the peace of mind that the motor will hold!!
personally, dont go for something that u might not need.......i think that your cam is holding you back though...........do a cam swap and see wat happens........them go heads.you should be at 500rwhp........(question, those numbers were on a dynojet or mustang.....dynojet right?) im still not sure if going to a 17/8 header will make that much more of a difference but i would hold off until the intake is done IMO
enjoy and keep tuning...........LAterZ
8 Second Club
Joined: May 2002
Posts: 1,043
Likes: 0
From: Toronto
Congrats obZidian... here's what you have to look forward to!
CHP magazine did a great write up about APE's 408 that you can read on my webpage in the magazine section @ www.avigdor.net . When will it be ready?
CHP magazine did a great write up about APE's 408 that you can read on my webpage in the magazine section @ www.avigdor.net . When will it be ready?
Originally Posted by necrocannibal
You think I would gain more from better heads or bigger headers?? My heads right now flow 295 @ 600.
do you have complete flow numbers on your heads?
here's my intake/exhaust #'s
.100 70 51
.200 149 110
.300 218 154
.400 264 197
.500 286 222
.550 292 228
.630 293 233
these are 5.7 heads with 2.02/1.60 valves.
Last edited by 383ss; Dec 1, 2004 at 01:41 PM.
TECH Enthusiast
Joined: Jan 2003
Posts: 564
Likes: 0
From: Fairfax VA
good lord!!!! almost 600rwhp through a 408!! That is absolutely UNBELIEVABLE. I wonder what size cam theyre using, and if they are in fact using those 6.0 liter heads on their website. Its making over 500rwtq by 3800rpm. Anyone know the price of this beast? shortblock and longblock?
Originally Posted by vmax1500
Congrats obZidian... here's what you have to look forward to!
CHP magazine did a great write up about APE's 408 that you can read on my webpage in the magazine section @ www.avigdor.net . When will it be ready?
CHP magazine did a great write up about APE's 408 that you can read on my webpage in the magazine section @ www.avigdor.net . When will it be ready?
Originally Posted by 383ss
I don't see anything wrong with your exhaust
do you have complete flow numbers on your heads?
here's my intake/exhaust #'s
.100 70 51
.200 149 110
.300 218 154
.400 264 197
.500 286 222
.550 292 228
.630 293 233
these are 5.7 heads with 2.02/1.60 valves.
do you have complete flow numbers on your heads?
here's my intake/exhaust #'s
.100 70 51
.200 149 110
.300 218 154
.400 264 197
.500 286 222
.550 292 228
.630 293 233
these are 5.7 heads with 2.02/1.60 valves.
Unfortunately I only know the 600 flow numbers. I got them used but called Jay and talked with him about them and he said they were an older design of port he was using but should work ok for my 224 cammed 346. I then had to rebuild and went to a 408 so I dont know if these heads are good at all for what I have.
We are in the process now of building a bad a$$ NOS fed 408. I opted for a Diamond piston, Manley I beam race rod, Callies Crank and billet main caps with ARP studs on the bottom end. The customer will run it with a 200 hit at first then step it up. It's not the cheapest solution but it will stay together.
