i have been working on my winter project and im really leaning towards texas speeds 408....with the aps tt kit does ne one have results from this combo...if so hows it work...are the 20g's to small for that displacement...im looking for a crazy street car mainly 93 octane....then race gas if im feeling crazy.....and yea i was also wondering do people just use their short block and put on a differnt set of heads for the for foced induction..or are the heads that come with the long block good peices....i know its alot of questions but ne replys would be greatly appericiated....thanks

 

I have a LS2 403 APS TT with a Alkycontrol methanol injection kit and it is strictly a street car and I love it. It makes about 770 RWTQ and 700+ RWHP at 9lbs of boost. The car has 10.76:1 compression so when not in boosted conditions it is still a total monster. I have 3:73 gears which are a little steep for forced induction but are great for the street. You can see my build on the Exotic Performance Plus website under project cars (Firehawk) and see most of the build. I have found the turbos to be fine for my build. I believe Peter at APS does not recommend them much past 400 CU. One last thing, if you want the car primarily for the street I would choose a conservative cam and go with a smaller port head for good air velocity...I'm using a comp cam XER 220/220 581 581 114+2 that Tony Mamo helped me pick out. I also am using a set of Tony Mamo prepped 205's. I really feel that my car is very well setup for the street. It drives very nicely and is super quick non-boosted and when you step on the gas it becomes a total beast. Kinda of the best of both worlds.

Good Luck,

Tim

 

I am planning on doing up a 408 most likely. Was thinking 427 but really really overkill. My car is street car also. My target is 850rwhp with the turbos and 1000rwhp or so with direct port nitrous.I have been considering the afr 225 heads and have a lingenfelter gt7 turbo cam but might go up to their bigger gt11 turbo cam since it is over 400 cubes could use a bit more cam. I have hptuners to tune with. Going with of course all forged crank,rods and pistons. Not sure on compression likely shoot for around 9 to 9.5 to 1.
I think also go with 3.73 gears since car is again a street car or 3.54. Dana 60 is planned rear end. Already running textralia twin disc might upgrade to triple disc depends on how the clutch works out. Might also go with 480le and stall and give up on standards.
Reading the post above does have me wondering if I should go with 205 afr instead of the 225s and stick with my bit smaller cam. Have to decide before spring. APS has in this section got some great results with their forged 346 with afr 225 heads and gt11 lingenfelter cam and fast 90 intake and 90 tb. I also have fast 90 and nick williams 90 tb for my build and have underdrive pulley also.
aps hit 700 plus on their conservative dyno and figure it was over 800 on dynojet equivalent. They are using bigger turbo wheels now but can't see any reason I won't get my 850rwhp with their base turbos on 408 at 15 to 18psi. If fall short a few hp not too worried. Much over 500rwhp is crazy on a street car anyway and traction will be very hard to come by. I was thinking maybe don't want quite a much down low anyway as if do have 3.73s then have lots of bottom and then can go with the bigger heads and cam to cut down on low end a bit.
Another cheaper idea but I already had the fast is to run the l92 heads and matching intake. Great results for a lot less than afr/fast intake combo. And the ls6 is a good intake for forced induction too. Good heads will help some and you can drop compression with them depending on chamber size like 72cc patriot or afr on stock engine will drop compression down not sure how much..full point to half point maybe?
I like the idea of hitting my goal power with a bit less boost. Less boost is a good thing in terms of head gaskets and stuff.APS was hitting around 20psi on their latest mule with the bigger wheels in their f body kit.Bigger wheels would also likely move the powerband up some and put out a bit less power at lower boost than smaller wheels.

Everything is a trade off. Most turbos cars are hard to hook up anyway. Plan on running nitto drag radials minimum or even something like et street radials.

If you are on budget a 370 iron block with stock crank and forged rods and pistons would also work very well. Even with stock heads.Go to boosted list and look at some engine combos.Even bone stock guys on here have gotten 500rwhp from the basic APS Kit. Thats not chump change for power either on the street and the area under the curve is great on turbo cars.

 

Just out of curiosity, do you know how heavy your meth spray is? Do you spray it lightly? I'm asking: when I do a build, as much as I'd like to only run pump, I'm probably going to run a splash of race gas or spray meth for insurance. Just asking if you're spraying a fat amount and are tuned for it (allowing you to have a little higher numbers).

I wonder if the APS compressor cartridge upgrade will work with a 427ci build... You do know they're already about to offer an upgrade

Will be interesting. I want to see some good, solid 93 pump numbers with a 400+ ci motor with the APS kit... That will most likely be my setup within about a year... I just don't know if I'll be splashing racegas or spraying meth...

Chances are I will do one of those two for insurance, then staying tuned for 93.. So if my meth failed (or staged injection, if I had the cash to drop) I wouldn't blow my stuff up. I'll save that issue for SpeedInc or W2W

 

My TSP shortblock spun the main bearings in 3k miles. Just an FYI.