Decadence75

iTrader: (17)

Hey everyone. I recently picked up an LQ4 that I plan to rebuild and put in the bird and would like some opinions/advice on what I have planned for it. I am hoping to make 500rwhp N/A and it will be mostly a road warrior that will be driven often. I wouldn't really say it's a daily driver as I'm in a situation where I only go into the office on a daily basis 4 months out of the year and the rest is 1-2 days a week. But it will be my primary vehicle other than terrible weather days.

I had planned to have a cleanup hone to 4.005 and make a 403 but the general consensus it to just go straight for the 4.030 and a 408 so that's what I'm going to do. Here is my current planned parts list for the build. All opinions and advice is welcome. Thanks!

TSP forged 4" crank
TSP 6.125 H-beam rods with ARP 2000 bolts
Mahle -4cc Flat Top Pistons
King main & rod bearings
Have the rotating assembly balanced
TFS LS2 GenX 220cc As Cast with PM guides and milled for 3/8 pushrods and maybe LS3 turned down valves
247/254 .624/.595 112+4
*BTR SLR lifters
ARP Main studs
ARP head bolts
ARP cam bolts
Melling 10296 pump
LS2 timing set
FAST LSXR 92 intake
NW 92 TB
FTP 104mm Lid
FAST 36LB injectors
04+ LS6 valley cover
Racetronix pump with body ground kit
If I can fit it in, a Mad Man manual steering rack
*Powerbond 25% UD pulley

* Items I already have are starred

redtan

iTrader: (5)

Unless you want compression in the mid 12s, stick with the 68cc chambers.

Decadence75

iTrader: (17)

Would mid 12s be too much compression for running on 93? Do you think there would be any valve shrouding issues using the large bore version of the head on a 4.005 cylinder? Thanks!

DREAMZ28

iTrader: (1)

Possibly, even if you choose a cam that drops your DCR into a safe range. There's a good read online about this. Basically it states that DCR is mostly accurate at low/moderate engine speeds and loads. when you're running a high compression motor with a big cam, even if the cam drops the DCR down into a safe range, once you get engine speeds up to where the cam is optimized, youll be seeing more of the 13:1 that the SCR is showing.


Its something along those lines, I wish I had the link but I found it pretty easy in Google

intenseblue

iTrader: (1)

68cc and stay below 12:1 I'd talk to a few sponsors about cams too. I believe youll be disappointed in a cam larger than mid 240s on a daily driver.

Decadence75

iTrader: (17)

Thanks for the tips guys. 68cc chamber large bore version it is then. Spent some time tonight on the tear down and have it to a shortblock now.

WS6ICK2k

In for results I'm planning a similar build w TF 220s and ls3 valves looking forward to seeing the results of the PRCs.

redtan

iTrader: (5)

Yes unless you're running a huge cam that will bleed off the compression a good amount.

What is the valve size between the two? But I'm pretty sure it shouldn't be a problem as that bore can take up to a 2.165 valve and I don't think the as cast heads are nearly as big, probably a 2.055 or 2.08 which is plenty safe for that bore.

intenseblue

iTrader: (1)

2.06/1.60 shouldnt be a problem and larger chambers are better.

Decadence75

iTrader: (17)

I was just taking a wild guess at a cam in the 24x/25x neighborhood but that might be a bit much for a road warrior/daily car. They both are 2.06.1.60 valves so I should be good on that. Looks like the consensus is that I should go for the larger chamber.

Thanks for the info!

Rise of the Phoenix

iTrader: (27)

Here you go. Get a set of these heads and follow the recipe the guy with the 402ci engine did to get 602 rwhp with a 23X/24X cam and a fast 102 manifold.

http://www.yellowbullet.com/forum/sh...d.php?t=786466

Decadence75

iTrader: (17)

Those are some nice looking heads. However their reluctance to give out any prices in forums or on the facebook page makes me think they would cost about double what the PRC ones are, haha.

Rise of the Phoenix

iTrader: (27)

I believe I saw they are $3,100. That includes the heads and port work.

fengstang

iTrader: (2)

pay the cost to be the boss

Rise of the Phoenix

iTrader: (27)

Or, pay the cash to haul some a**

Decadence75

iTrader: (17)

If I had some deeper pockets I'd go for them but that's just a bit out of my range. Thanks for the link and info though

COSPEED2

iTrader: (7)

Use a 4.030 bore. Use mahle power pak pistons and rings. Never look back. We can get you everything you need from the tsp heads to custom cam to complete rotating assembly for a package deal price.

Let us know!

Decadence75

iTrader: (17)

It will be a while before I'll be able to make the order, just in the planning stages right now but I will definitely keep you guys in mind!

COSPEED2

iTrader: (7)

We can help you plan also. Easier to stay on track with one supplier/prof to work with alot of times. Its very easy to get caught in internet myths and off in left field.

Decadence75

iTrader: (17)

Sounds good. I updated the proposed list in the first post if you want to check it out and make any suggestions.