408 build process

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May 10, 2009 | 12:57 AM

wesam

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408 build process

I'm now in the process of building 408 motor looking for 500 rwhp and need advises

- i took 6.0L iron block which is bored to 4.03 then i will ordered a 408 rotating assembly with
- Diamond Racing Pistons -10 cc
- Mahle 4.030" plasma moly rings 1.5/1.5/3.0
- Callies CompStar LS1 rods 6.125 length std. jornal
- ARP 2000 rod bolts
- Callies CompStar 4.000" stroke Crankshaft 4340 Forging 2.100" journal
- ACL LS1 Main bearing set (race) standard size
- ACL SBC standard jounral rod bearing set (race)

i will put speed inc ss3 cam 242/250 611/619 114
with my current mods and i will convert my car to M6 i will exchange my A4 tranny with my friend M6

i need your advise in the following points:

1- i have a 1 3/4 kooks headers with a 2.5 CB will this rape a lot of power ? if so will putting an electric cutout after collector will solve the problem ?

2- should i put ARP head studs ? or the ARP bolts will be fine
( i have FI as future plans with changing the heads to biggest CC heads to lower the compression which will be 11.5 with this setup )

3- some one told me that my 59cc heads will lower the efficiency ( power ) is this true ?

4- do you recommend another cam which will idles smoothly at 1100 and still give good power till 7200 rpm ?

5- Are those good choices for the rotating assembly components ?

6-What spark plugs to use with such high compression engine will the TR6IX be fine or should i go colder ?

May 10, 2009 | 04:02 PM

wesam

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any body ??

May 11, 2009 | 02:59 AM

wesam

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bump bump

May 11, 2009 | 09:59 AM

99Ls1fever

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From: Eaton, Colorado

Curious why the LSA is so high? on a n/a motor usually the LSA on a cam is more like 111 or 112 to scavange more air. I wouldnt run that high of LSA unless I was running a F.I. Motor. I personally have already done a 408 build. It seems like we are pretty close on the motor build. I used the TSP Giant and put down 531. So I figure you should atleast hit 500.

I would not reccomend using ARP Head Bolts, I would reccommend the ARP Head studs. It is not reccommend even by APR to use there ARP Heads bolts if you plan on rebuilding the motor or pulling the heads in the future. For the simple reason, it is a allummuim block and is prone to issues on the head threads from constant thread and re-thread. When you use the head studs they will not have to be removed ever again and are the smartest way to go. Heads suck to the block on head studs, heads are held down on head bolts.
Use electric cut outs or you will regret it. Always a smart discission prior to what anyone things. I run dual cut outs.
TR6's best plug to use good hot burning n/a plug. Same plugs I used in my 408.
Never have used those bearings before so I dunno.
If you are going to run this engine, I wouldnt rap it to 7200 rpms unless you have the air for it. Since this is such a high compression motor. I would run nitrous and spray the hell out of it. It will give you big power and your motor will have no issues with it since it is forged. I ran a 250 shot and my motor loved it and ate that **** up. good luck

May 11, 2009 | 10:06 AM

wesam

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the big LSA because i have FI as my future setup and i don't like shaking and rough idle i want it to be as smooth as possible.
the second point it will be iron block not allummuim block so could i use the bolts ?
by the way what was your setup which made 531 ?

May 11, 2009 | 10:14 AM

99Ls1fever

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From: Eaton, Colorado

Quote:

Originally Posted by wesam

The cam isnt right for what you are trying to do though. You are a high compression motor right now. So when you decide to rip the motor back down to switch out pistions, put your new F.I. cam in. The LSA is to high imo for n/a motor. You will not scavange enough air. My 112 LSA was not a rumbler at all, with full exhaust and the cut outs closed it was quite and a non threat motor by the sound of the exhuast.

I would not go cheap when building a motor of this magnatude. Yes you can run the arp head bolts. But if it was me, and I am not rich. I would just save the money and use the head studs. They are just perfectly made for race application engines.

My Setup was a Texas Speed 408 Short Block, 11.2-11.3 to 1 compression, LQ9 Stage 3 Patriot P. Heads. TSP-Texas Giant Cam. Fast 90/90 Ported TB/Intake, 250 Shot. I was 531 n/a and 770's with Nitrous.