OK, I'm building a turbo kit for my RX7 with an LT1 and need someone to tell me what parts to buy. Here are the parts I'm buying, just need to know who to buy it from and what brand/kind

Turbo (TO4B?)
injectors
wastegate
header flange
BOV
rockers
valve springs
retainers
pushrods
lifters
cam

I really need to know if the TO4B is big enough to run like 6-8psi. I don't want to go overbored just yet. Also need to know what size injectors to get for 800hp+ (for later).

 

I would say a TO4 would be big enough for 6-8psi on an LT1, but will not make your 800HP goals for later. Just build it for 800HP now if thats what you know you will eventually want. You can always open up the waste gate and get the boost down.

I will make a few suggestions for the brand of each part.

Turbo, I would get the common 76mm from turbonetics, precision, or innovative, those are all really popular.

Injectors-seimans deka, waste gate- turbonetics racegate or their new really big one, For all the valve train parts you can get comp cams chromemoly parts they won't break the bank and are pretty nice parts, and I would get a recommendation from Cam Motion for the cam.

 

I think I'm going to stick with a smaller turbo for now so I won't get huge lag and only end up with 6psi. I'll probably end up with a T88 later. For the wastegate, can I get a 38mm? I realize it is a small gate but I am also using a pretty small turbo.

Injectors, where can I find seimans?

 

Forgive my ignorance but if you had a small turbo wouldn't you want a larger wastegate? A small turbo will allow less exhaust through compared to a larger turbo meaning alot of the exhaust would need to escape out the wastegate, therefore you would want a larger WG with a smaller turbo, right?

 

Turbo (TO4B?)
I'd go with a T-76 GTQ trim

injectors
Siemens-Deka 72-83lb/hr injectors, low impedance

wastegate
Tial, 46mm

header flange
Don't know off the top of my head - you could just get some 1/2" plate and have them plasma cut.

BOV
Tial

rockers
Comp cams pro-magnum

valve springs
depends on cam, rpm, etc.

retainers
Titanium

pushrods
chrome moly

lifters
comp "r"

cam
depends on your hp/rpm goals. Best bet is to talk to someone who has experience camming turbo setups. Will also be highly dependant on what turbo you end up, your exhaust setup, and what boost levels you want.


Chris

 

actually a smaller turbo would be fine with a small wastegate. With a small turbo a big engine would suck up more air. This makes the turbo work harder to build boost. If the turbo works harder, the wastegate can be smaller

 

Just ordered a bunch of parts

TO4B turbo
Tial 38mm wastegate with .3bar spring
1.7 forged rockers
Comp dual valve springs
Comp Ti retainers
7/16" rocker studs
Comp chromemoly pushrods
Comp Pro Magnum lifters
Comp 224/236 114 cam
pushrod guideplates
Areomotive fpr
1/2" header/turbo flanges
Apexi blow off valve
Lucas 42# injectors

All in one day Can wait to start building this thing now. I wonder what I'm going to do for the heads now? Off to another post

 

What made you buy that cam?

 

Yeah, not the cam I would have gone with for a turbo motor...


Chris

 

yeah, im pretty sure thats a blower cam......not great for turbos.

 

as others said, that is a blower cam, it will work horribly with your setup.

1.7 rockers, very bad choice. valvetrain geometry and just plain lift is going to be too high.

you really should listen to people...

 

what cam should I have gone with then? I figured a cam for forced induction should have worked good for what I was building. I had no idea blower cam is different than turbo cam

 

blower cam is usually higher exhaust duration than intake, like 224/236

turbo cam is usually equal or greater intake duration, like 220/220 or 230/220........the smaller exhaust duration creates a higher exhaust velocity, spooling the turbo better...

atleast thats my understanding, im sure someone can give a better answer.

 

Thats why you should listen when people give advice

 

The wastegate size depends on how much boost you are running, and engine size. Running 6 pounds, the wastegate needs to get rid of more exhaust gas, than if you were running 30 pounds. The Tial 38mm should be fine, but if it doesn't keep the boost down, then just get a bigger one.

What are the specs on that turbo? Why did you choose that? I don't think a TO4B will do well at low boost levels.