Hey guys, I have a 2003 LQ4 in a 1987 Toyota Supra.

The car puts down 400rwhp currently. (thru a 4L80E with YankSS3600)

Combo for this HP level below:

03 LQ4, stock pistons
Professionally Ported 799 heads shaved .030, with stainless valves, and a 5 angle valve job. (61cc chambers)
The heads were flow tested at 306cfm at .650 lift
Stock GM headgasket
Roughly 10.5:1 compression
.550 lift springs
224/230 .553.547 111+2 cam
Custom 2" primary long tube headers
LS6 intake with stock truck throttle body (DBC)
LS3 injectors
7.350 hardened pushrods
91 octane

Future Plans???:
Fast 102/102
Cometic .040 head gasket or .045 (get better quench & compression)
Bigger Cam
LS7 lifters
.650 lift valve springs
91 octance still

Curious which cam / headgasket / intake manifold combo you guys would run to try and get as close to 500rhwp as possible without running into PTV issues? Will a bigger MAF be needed aswell?

Some pics and a video for you guys!






Video of exhaust & idle now

https://www.facebook.com/699160521/videos/10158664961530522/
P.S. I know I probably won't see 500rwhp thru an automatic, with this displacement and heads. But 460whp should be no problem!

 

Nice

turbo, blower

forced induction!!!

 

Yeah, don't be disappointed if you come up short on the dyno.
The real power will show at the track with your trap speed.

 

I’m not looking to boost the car for a couple years. Just looking for a cam upgrade to maximize my combo.

how about a 236/242 .615 .612 111+2 ?

 

Cool Build!
Looks very well executed.
Cam Motion Titan 5 LS1 , 232*/238* 113*+4* .621"/.604"
Mamo Motor Sports (MMS) Ported MSD Intake (The MSD by design will
Peak 300-500 RPM higher than the Fast, 6800-7000 VS ~6500).
Cometic .040 Gasket, goal should be 11.0:1 Comp minimum.
Just my .02
Good Luck

Stack Silver

 

This is exactly the kind of recommendations I am looking for! Thanks for contributing!

 

I have a hunch that getting colder air to the intake (or getting less of the hot engine bay air) might get you a few more horses. So, how much do you really need that passenger side headlight?

Regarding the MAF question, if you do the Fast 102 manifold and a 102 TB, you'll want a 4" intake tract all the way to the filter. I did that in my C5 with an air intake that uses an LS7 MAF sensor (Halltech Killer Bee) and that worked well. Except that I ended up going to an LS2 throttle body because 102mm DBW throttle bodies are still hit-and-miss with C5s, but that's a whole other story.

 

You’re not getting 500whp NA without a lot more compression, race gas, and a boat load of revs. Forget about any kind of street driveability. It will also be a dyno queen because the power band will be totally useless for anything - even the track.

 

Chasing a number at the track with that combo is where it's at. Chasing a dyno number with that drivetrain is a fool's errand. High dollar heads, correct big cam, ported MSD intake, matching big TB may get you close but you are going to run into a streetability wall pretty hard before you get there. It's doable, but my guess is you won't like the cost or driving on the street with the results unless you really go all in with someone like Mamo.

 

aftermarket heads....monster cam...lots of compression...... Electric water pump.... electric power steering pump ...... crank scraper.... vacuum pump... will be needed at a minimum.... every stone needs to be turned especially on a stalled auto....even then don't get your hopes up too high chasing a dyno number... like dannyz said earlier in this thread, look at the MPH....

 

Crank scraper should be in the list somewhere

I'd go with the .045 gasket, ws6store has them for around $70 if I remember correctly

58 or 59 cc heads. With 59 cc and .045 gaskets that's 11.04:1 using summit's compression calculator figuring 7 cc dish, .005 pistons out of the hole. They usually come out of the hole a hair more like .006 .007 which moves it up closer to 11.1

Light weight drive shaft can help

Less belt and pullies, or at smoother belt routing can help some (ripping the belt through curves uses power, accessories use power, rotating mass uses power) so maybe also consider a lighter front pulley, but don't go full race super light, you still need dampening.


Edit: your exhaust is F*****ing amazing. And are those Fikse's???? Look like FM5's but I didn't think they made them with bolts on the front side

 

Oh and go with johnson 2110 lifters ($400 if I remember right) instead of the LS7's, if you're going with a drop in lifter. Wouldn't be surprised if those give you 10 or so in upper rpm's

 

Just use comp 469 ca m.. 231/247 /113 109 centerline or something. Think holdner almost made 600 with that and fast/cathedrals. Or since u probably smaller valve push it more. 231/251 or something on 112 or 111

 

How big is that single exhaust? It's beautiful, but you went to the trouble of 2" primaries on your (also beautiful) headers, and then put a single exhaust on it? If it's 4" single out the back, ignore this. :-)

 

Going strictly on appearances in the under-car pic of the exhaust, the "single" part of it DOES look like about 3.5" - 4.0". So it might be OK...

 

I already upgraded my push rods, would switching to these lifters from the stock LQ4 lifters require me to change pushrods again because they are a different height or need different preload?

I've seen all those videos, thats what gave me some hope. Guys have made 600 crank HP on a 6.0 before. Think running that much duration would give PTV issues without fly cut pistons?

Its a 4 inch single all the way out the back, with just a single bullet muffler at the end.

I wonder how much power, if any, i'm leaving on the table with my current cam in this combo. (224/230 .553.547 111+2 )

 

Yes I believe I read they take a little bit shorter push rod. I can't say for certain, and from what I remember they use a little less pre load, I think it's .030 with the johnsons. I would contact Johnson and get the info direct from them. But if you're gonna mess with heads, gaskets, etc you very well may need to change pushrod length anyway.

On the cam, especially if you raise compression some, you can go bigger and still have a great power band and good driveability. I would look at something with a 230-234 intake and around 8 or so degree split, 610 ish lift. LSA is up to you, if you want it to come in a little earlier go 112 if you want to have power a little higher 114. At a random guess I'd say you'd get 15-20

 

Member Public Enemy... his LS2 6.0 makes over 500 rwhp threw a stall. His combo is consists of TFS BTR 220s, Fast 102mm, BTR 235/242 cam. Car run 10.5s as well to boot.

 

And how much curve down low would the 469 loose to a 234/242 on 113?

not suprised on tea combo that sounds about right.

 

https://ls1tech.com/forums/generatio...inally-c6.html

TFS for the win