lil john

To New School 72: I'm looking to do the same thing with a 408 and 4150 throttle body, with that 108+4 lsa do you run A/c and how does it run at stop lights. Looking at 239/255 dur. @ at .050. I'm hoping that with FAST ecu dialing in the cylinders will be easier. Any-thoughts ?

newschool72

iTrader: (12)

The Fast ecu will smooth the idle out significantly . The cam in mine was very choppy the first time I cranked it, but now with minimal time to self tune, it is really smooth for a 108+4 LSA. I am running Vintage Air AC and the idle step up on the fast does a great job of keeping the car running smooth, even with the ac on ,in gear. All you have to do is trim the fuel back a little at a time to get to a good idle A/F ratio. The preset idle is 13.5. I have mine at 14.2 now by adjusting it in the "advanced tuning" on the hand held. It is a great system if you make sure you are at the right fuel pressure and set the TPS right. Good Luck!!

lil john

Thanks, called Dr. J's porting service about porting Edelbrock Vic JR intake. [408ci. with 11.8 comp. with a 235-239/255 dur. at .050 .688/.709 108+4 with 1.8 rocker. 4l80e trans with 3400 stall and 3.73 gear 3100 pound Malibu street car.

newschool72

iTrader: (12)

That should be a brutal street car. Are you planning to run the original EZ EFI on the engine? You can go as high as 60 psi on the injectors and it is suppose to handle 650 HP. Im running the suggested 43 psi on mine that is good to 550 HP. I think my engine on a standard engine dyno should be good for 530ish or right at 400ish on a chassis dyno. I plan to run down to my local dyno shop when I get the cash for a tuning session, just to get an idea what im making and to see if the spark curve and EZ EFI is doing what it is suppose to.

lil john

Thanks, it was you who helped me because everyone told me that this was to much lift(valve-train problems this is the Lingenfelter GT21 cam:243/259 691/.702 Comp Cams said that they can take out -4 on the intake side .239dur. & 21 degs. of overlap)and that it would run like a ****. Lingenfelter salesman said that they run this cam all-day long in Z06's without any problem with GMPP lifters.What I wanted was a NASCAR looking engine that I could run on the street.Waiting for TFS 255cc LS3 heads, Check out Flow Chart for these puppies. When I get the Vic Jr intake I will have it ported and get the Carb. pad modified to run 4500 throttle body( I just like the way it looks). I expect nothing less that 640-660hp with around 370cfms at.650 and the cam goes to .688 lift with a tight lsa. to keep things crisp. Oh by the way who makes a low profile Air cleaner for this type of set-up. Looking to get as low of a profile as possible and will it clear the throttle linkage.Tried calling K&N,busy dial tone: I'll try again. Thanks again!

newschool72

iTrader: (12)

I have the spectre low profile bonnet on mine with the tubing going through my aluminum sheet metal fender wells to a cone filter. I wanted the cold air advantage because the Fast shows the air temp going into the throttle body and after 15-20 minutes of idle time I had air temps between 120-130 under hood. I installed the cold air setup and my temps are within 10 degrees of the outside air temp. That is worth a few HP on its own.
Before I did that I customized a drop air filter base to fit over the throttle linkage and fuel rails. I used Percys miracle cloth to fill in the cut outs and sealed the edges with silicon . It looked like a hack job from underneath but you cant see it installed. it worked well, but I wanted the cold air advantage so I went that way.
I still have the air filter if you want it. PM me for a price if it will fit. the throttle body on mine is 4150 style. I don't know if its the same diameter as a 4500.
I would recommend a call to one of the grinders on LS1tech OR Bullet Racing to talk about a cam for your engine. I have very steep ramps on my cam but I don't have any valvetrain issues that I can tell. With a 1.8 rocker and the duration you are running a .700 lift doesn't seem like a problem to me. Call Tim at Bullet to discuss your setup, or Martin at Tick.

lil john

Oh the Cam is OK this my 1st ls cam and I'm going big or I'm going home. I found a low profile air cleaner for 4500 throttle body it's the Holley Power Charger Air Cleaner Assembly PART #: 64280, but I think you are right about under hood air temp. I'm hoping that with this much lift and a good ported intake it will be able to supply the heads all the air it wants, because L76 and FAST can't supply this amount of air. I was trying to get the LSA. and the Dur. right. on the cam but I talked to Ron at Vengence Racing about the custom spec cam I had in mine and he said it's going to be a helluva ride once it's dialed in.Oh here are the specs on my heads compare to L92 heads ported or non I have in my closet a brand new pair of L92 heads I got Bare in 08 for 175 ea.

Trick Flow® GenX® 255 Cylinder Heads for GM LS3
Combustion Chamber Volume (cc): 69
Intake Runner Volume (cc): 255cc
Exhaust Runner Volume (cc): 87cc
Intake Valve Diameter (in): 2.165 in.
Exhaust Valve Diameter (in): 1.600 in.
FLOW DATA 4.065" BORE
Lift Intake Exhaust
0.100 71 59 55
0.200 146 113 122
0.300 231 171 199
0.400 294 215 250
0.500 334 240 277
0.600 363 252 290
0.700 382 258 298
This is with a 4.065 bore If I was to ever build bigger I wouldn't need new heads: Think of how they would flow with 4.185 bore and a larger intake valve.

newschool72

iTrader: (12)

The TFS heads flow great, no doubt . For my build , the stock LS3s are all I need. Maybe clean up the exhaust ports a little, but with a good split on the cam they will be OK. Good luck with your build.
More to come with mine as soon as the laptop gets here. I am trying to plan a trip to Silver Dollar raceway in the next couple weeks for some real #s. Stay tuned!!

newschool72

iTrader: (12)

Im looking for opinions on the best way to tune my advance curve. Dragstrip or Dyno?? The dyno will give solid comparisons between advance curves, but the dragstrip will give real world results. As in taking the car weight, drag, and air coming into the engine under actual conditions.
I want to get the static curve just right, then play with the map under street driving conditions till everything is well rounded and RIGHT.
So...whats the best way to go?

speedtigger

iTrader: (16)

I have only ever done track tuning with mine. I could see how a dyno could get your really close though. Then just final tweak it at the track.