|05-20-2013 11:45 PM|
|ap72||Depends what you call a lot. I'd liken it to the difference between a 650 and an 800 series carb, some think its a big difference and some think its almost the same.|
|05-20-2013 09:33 PM|
Max bore did the stock 60mm tb . bored it to 64mm . Tappered the inlet at 67mm.
Is that a lot?
|05-20-2013 06:14 PM|
Tipping in to load conditions pops a wrench it goes lean and back into open loop. I read somewhere this is because the map can only read so much boost. So online they say you can get a one way valve that fits in front of the map to keep it from sensing positive pressure. Possible this is not the case, and there is something else wrong.
Substitute the word load for boost . Manifold pressure is building faster than normal while increasing load. It goes lean everytime. I really am not sure why.
Megasquirt does get good recommendations but it is not street legal.
Using RC 310cc saturated type injectors. The calculator suggests should be right on a 1.9L at 180-200whp.
|05-20-2013 03:59 PM|
Secondly, without retuning for larger injectors you're getting that cam sound because your giving it way too much fuel at idle, and if they are WAY over the stock size they can only open and close so fast so you'll never get a perfect idle even with tuning.
until you get it tuned for the injectors I would drive it as little as possible.
From the little research I did most turbo SC2 saturns are running megasquirt, which is a great cheap EFI system, and NOT OBDII compatible.
There may not be a easy tuning solution for that car.
|05-20-2013 02:37 PM|
I upgraded the fuel system. larger injectors, pump, and higher fuel psi. This is new stuff to me so I am playing it real safe watching the wide band. Currently I am looking into a piggy back injector enrichment system for the turbo to replace the rrfpr. There is also a AFC hack that I am looking into for the Honda vehicle. The Saturn I have not gotten word back on what the owner wants to do, and still waiting for the turnaround on the TB from VMS.
I am open to suggestions. How would you add fuel for the boost, on a obd2 system? It has to stay in closed loop part throttle boost. I
I would enjoy getting to a track again at some point. According to the torque software that is based off of the vss for distance, the twin cam was in the high 14's with some boost. Like a estimate 180-190 whp.
I like to work on the RWD vehicles but there are so few to find. You get bored and end up with a 4 banger.
I never realized that the larger injector size you go the worse it idles...kind of like a cam without the lope. Could be that is the untuned condition. Gimme a some time, Ill get the bugs worked out.
edit- the ones pictured came from maxbore.
|05-20-2013 02:17 PM|
|ap72||Are you going to bother to tune the computer for the change or just run it untuned for now? did you get any track data for before and after?|
|05-20-2013 02:09 PM|
Here are the pictures promised.
|05-08-2013 08:47 AM|
If you want to step up to larger throttle body, there are ways to keep them from becoming "twitchy" and from being like an off/on switch.
Check outthese Vortec t-bodies. As you can see there is a 1/2 moon shaped device that is specifically designed to prevent such scenarios. The Vortec 4.3 has a bigger 1/2 moon device than teh Vortec 305/350 t-bodies.
The 305/350 t-bodies are 75mm, IIRC the 4.3 t-bodies are smaller at 65mm, but I may be confusing t-body size with MAF sizes.
Forced induction is very sensitive to air restriction on such through t-bodies, but not as much with blow through t-bodies. If this setup is a suck through t-body mods or upsizing can make dramatc diferences.
|05-08-2013 05:14 AM|
taper can increase velocity and or smooth the incomming air.
on a tb i doubt it gives any noticeable increase , unless of course u have a tb that is horribly designed
when it comes to replacing a stock tb with a larger or bored out unit most ppl think they are feeling a hp increase , when in reality if u take the stock tb at 1/4 throttle opening and then the larger unit at the same throttle opening the larger tb will alow more air into the engine.
so u dont have to step on the gas as far to accelerate like u did with the small stock tb
go to large with a tb and the throttle becomes more of an off on switch
|05-07-2013 08:24 PM|
|spinn||A clarification , in case somebody cares, the throttle body, was originally from a Geo ? and is 52mm. It is a common upgrade, or was. When these cars were made, supposedly. If you look into a Saturn SL factory manual the LLO tb of that year are 45mm. Just so things match up and make sense.|
|05-07-2013 06:40 PM|
In true bonehead fashion I did not T gauge/mic/caliper it before shipping it out. According to the manual it says 52mm. I probably should have measured .
The next one that will be sent is a Honda and 60mm.
What about tapering the body? Would that help out with anything?
|05-07-2013 06:07 PM|
basically since the air is presurized its being forced threw the opening.
anyways if u want to know if ur tb is to small in n/a form hook up a vacum gauge and go wot. as long as it gets to 0 vac its not to small , if u are seeing any vacum at wot then u know its a restriction
btw whats the size of the butterfly on the saturn tb?
we use single 48-52mm tb's on engines upto 3.6L of displacement without them being a restriction
|05-07-2013 04:57 PM|
In a week or two when it returns I will post before and after.
By the way, your videos are very inspiring.
|05-07-2013 04:50 PM|
the twin cam saturn engine will make stupid power when turbocharged.
search youtube and u will see some of those saturns making 400+ whp on pretty stock engines
if u do turbocharge it save the 100 bucks on the tb mods as once ur turbocharged they wont make a dam bit of difference
i used to have an sc2 with custom cams/adjustable timing gears 4-2-1 header full ex system, ported and shaved head
was a fun lil car
one of these days ill buy another one to turbo charge prolly be a 3 door sc2 manual car
|05-07-2013 04:31 PM|
It is $50 for the service from the guy. If it works out and I like the work, then I will send him another to be taken to max bore. They replace the butterfly and smooth the screws.
Village does it, redline, maxbore, etc. A search will lead you all over. This guy works with Saturn stuff, and this tb is off a twin cam.
I feel kind of stupid hopping up a saturn, but if it helps it might be worth it. You add a turbocharger and you never know.
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