I ditched my turbo.......

[rabbitman]

I got so tired of it not working right that I yanked it last light.

I had a 2.5" pipe bent up for the DP then cut the toilet bowl off the stock DP and welded it to the 2.5" pipe , so now it's 2.5" all the way back!!! I left the gasser intake installed.

It's rather loud, when I floor it it's pretty loud then at 3000rpm some kind of resonance starts and it get's WAAAY louder, sadly it's sounds quite like a ricer at that point .

My thermocouple can no longer read all four cylinders so I put it where the number 2 and 3 exhaust runners meet. I didn't touch the fuel settings in taking the turbo off.

With turbo the egt's would soar above 1300F and then I would let off, now without the turbo the egt's get somewhere around 1150F max all the while belching that wonderful black stuff out the tailpipe .

It's a real slug too, possibly due to an intake restiction since the inlet into the manifold is only 1.5".

I wish I could have the turbo tested to see if it really was the problem or if it's some other part of my setup, but alas, I don't feel like parting with the dough it this time , especially since the wheels look perfect and the bearing's are good.

I read about other people's vnt's making tons of boost while mine even with the vanes closed never even pegged the 15psi gauge........

[rabbitman]

Yeah I'm sure my intake is restricted, it is soooo gutless compared to before I ever turboed it.

Seems like it's got no power band,  like if I mash the go pedal in second @ 1000rpm it'll pull out and speed up real even.

The other weird thing is at WOT it smokes black yet the egt's isn't as high as before turbo, my theory is that it's starving for air and thus can't burn hot enough to make excessive heat.

I'll mod the intake and see if it helps.

[maxfax]

1.5" inlet is awfully small compared to say a stock N/A intake.. I'm not overly turbo savy, but could the small intake be causing your boost issues???

[rabbitman]

1.5" inlet is awfully small compared to say a stock N/A intake.. I'm not overly turbo savy, but could the small intake be causing your boost issues???

I've wondered if it could be the cause, in my build thread I had pics and asked about it and nobody seemed to think it was a problem.

I know to have boost pressure you gotta have flow and if it wasn't flowing good enough thennnnn......I don't know. Maybe it would surge but it never did, I should've tried to put a boost guage right at the compressor outlet and see what it read.

I've never delt with turbos at all until this so it has been quite a learn. Maybe I'll fix up the intake inlet better and try the turbo again, it's pretty easy to put it back in just takes time is all.

[Rabbit on Roids]

i think the stock TD manifold is grossly restrictive. is that the one you have on there? anything is better than a stock TD manifold if you dont have boost going through it.

[rabbitman]

i think the stock TD manifold is grossly restrictive. is that the one you have on there? anything is better than a stock TD manifold if you dont have boost going through it.

I'm using this gasser mani off a '80 1.6L bunny.

[burn_your_money]

I'll guesstimate that the exhaust gasses are less dense and therefore are not heating up the EGT probe as much/quickly as when you had the restrictive turbo on there.

[Rabbit on Roids]

i think the stock TD manifold is grossly restrictive. is that the one you have on there? anything is better than a stock TD manifold if you dont have boost going through it.

I'm using this gasser mani off a '80 1.6L bunny.

yea, with a turbo hooked to that it would be fine. but with no turbo it would probably be a wee bit restrictive.

[rabbitman]

When you had your manifold off, did you plug the ports to keep crud out and forget to remove whatever you used as plugs?

Nope no plugs, I just don't drop things were they shouldn't go

Yeah this is weird, my top speed is around 70mph and it's smoking black the whole time. Before turbo I could go 80-85......kinda. Bottom end power isn't too bad though.

I thought the fat exhaust would help a lot but it just makes it really loud.

[burn_your_money]

Perhaps your exhaust is too big. I noticed a drop in power when my muffler fell off. At least I think I did. The butt dyno lies...

What air filter are you using?

[rabbitman]

Perhaps your exhaust is too big. I noticed a drop in power when my muffler fell off. At least I think I did. The butt dyno lies...

What air filter are you using?

The air filter setup is the stock NA plastic part (minus the "snorkel" piece) sitting where the stock td airbox would sit with the top part off the 1.7 carbed gasser. That has a 2 inch aeroduct connecting to the 1.5 inch hose that goes into the gasser intake. Confused? This useless 'puter won't connect to the camera or I'd just post a picture of it.

Overall the only part smaller than stock is the 1.5 inch hose/intake inlet.

I think part of why it feels gutless is 'cause it SOUNDS like it should have lots of power, however a top speed of 70ish is rather lame.

Yes it could be that the exhaust is too big, contrary to what most think, these do actually have slight valve overlap.
If I'm correct in thinking that the velocity of the escaping gasses is supposed to help draw fresh air in then I've messed that up with the fat exhaust so that affect is gone.

The valve overlap (probably) wouldn't affect a TD since the turbo doesn't allow it to free flow anyway.

 I almost went with a 2" or 2.25" dp rather than 2.5" but it's a little late now.

[theman53]

That overlap is why my head builder said you will get gains over 20 psi on the TD engines, but it is diminising returns. He said I will blow it past the valves a little.
Maybe you could route it a little differently for a ram air setup and you should be happy with it.

[rabbitman]

Do you have a VAC gauge?  If so, plumb it to the intake manifold where you were reading boost and see if you are registering vacuum.  If you are, then your intake is too restrictive.  The 2" aeroduct might be the issue.

Why do you think the aeroduct would be the problem when I have some 1.5" in the line?

Good idea on the VAC gauge.

[burn_your_money]

I'm sure you know this but you would be best to preform the vac test at 70mph, or redline in whatever gear of your choice.

[rabbitman]

I hooked up a manifold pressure gauge yesterday and at 4700rpm (about the highest I ever go) the pressure went from 28.75inhg down to about 26.5inhg.
I know it's best to not have any drop but I don't what's acceptable.