Need more bottom end!

[my98GST]

After installing my td06h 20g, I've come to realize I really really need more bottom and mid power. I have tons and tons and tons of top end but I just have no bottom end. What are some more mods that I could do to improve my bottom and mid power? I WILL NOT RUN NITROUS!

 

[Splitpi]

Cam Change?

The issue is the turbo require a certain exhaust flow inorder to spool up. And that takes time (RPM's actually) which is why you are not seeing the bottom and mid power that you want. If the cams don't fix it (help) your stuck with what you got. That is the trade off of larger turbos versus smaller turbos.

Also do a boost leak test.
http://www.vfaq.com/mods/ICtester.html

Edit: added link

 

[flyinghighlm]

CAMS CAMS CAMS, those are huge and mill make a noticible difference! Look at what HKS has or FFWD, they should be able to help you find the right grind to give you more of what you want.

 

[VelocitàPaola]

I WILL NOT RUN NITROUS!

Will you rebuild your engine? How about a 2.3L stroker? That'll spool your 20G quicker...

 

[DSM_TSI_95]

Also you might consider doing some head work like porting and polishing. Replacing those valves. Anything that will help the motor "breathe" better will help you out with the bottom and mid end power range. I had the same problem i went from a 16G to a T-70 on stock internals. Cams and head work will help you with this problem.

 

[my98GST]

What kind of cams would you guys suggest? I've been reading and all I've gathered and really heard about are the 272's and they pretty much target top end power as well. Yes I will be in desperate need to rebuild my engine towards the end of summer, how much would we be looking at to make it a stroker?

 

[BaddAssGst]

What kind of cams would you guys suggest? I've been reading and all I've gathered and really heard about are the 272's and they pretty much target top end power as well. Yes I will be in desperate need to rebuild my engine towards the end of summer, how much would we be looking at to make it a stroker?

I'd recommend the smaller set of cams like the Comp 100s or HKS 264s. You could go with the combo of a 264/272 but it's really not needed with a turbo like that. I personally run 200s but I was torn between the 100s as well. Having a quick spooling turbo (18g), I opted for the 200s.

 

[Slippi84]

What were you running that you feel that a 20g has so much less bottom end because I know even my 50trim didn't loose THAT much bottom end compared to my 14b grnated it lost some but not to the point where I was suprised. Maybe you just had unrealistic idea of what kinda low end power you would have with your new turbo. But anyway like they said cams will help. WHat you want to do is get a 272 or similar set of cams and get cam gears and retard the timing of the exhaust cam and you will spool faster and see more low end

 

[BaddAssGst]

What were you running that you feel that a 20g has so much less bottom end because I know even my 50trim didn't loose THAT much bottom end compared to my 14b grnated it lost some but not to the point where I was suprised. Maybe you just had unrealistic idea of what kinda low end power you would have with your new turbo. But anyway like they said cams will help. WHat you want to do is get a 272 or similar set of cams and get cam gears and retard the timing of the exhaust cam and you will spool faster and see more low end

Or just get a set of comp 100s. Unless he is revving past 7500, they is no need for 200s, especially if he's looking for low-end. Comp's drop right in with no degreeing necessary so the added cost of cam gears kind of makes it a more expensive mod, although if you were ever planning on getting them, now would be the time.

 

[my98GST]

It feels like its hitting a brick wall until 4500 then its out like a fat kid in dodge ball.

 

[Talesin]

I'm assuming that you had it re-tuned with a dyno after putting on the new turbo? If not, at least some of the brick-wall would probably be running rich well before you finish spooling.

And though most would find it silly; if you have a silencer for your exhaust, try putting it in. With mine, the difference with and without that exhaust restriction (additional backpressure pre-spool) was very noticeable. With the silencer, it had a good bit more low and mid range. Without, the low and mid became anemic, but the top end gained a whole lot of pick-up and the spool finished a bit quicker.

 

[my98GST]

No, I havent had it tuned just yet, I'm waiting on just a few more parts before I put it on the dyno and have it tuned. Where could I find the best deal on a set of 100's or 200's? Which would you perfer? I have the following mods. 550cc's, 255, safcII, 3" turboback, td06h 20g, 28x10x3.5" fmic short route, Greddy type-s, injen intake. The car will see the drag strip a few times a year, a few autox's, lots and lots of spirited street driving, and blasts through the mountains since I live in Tennessee... Plus I'm also shooting for 350ish whp.

 

[Slippi84]

The cam selection is up to you just know that 200's give you more top end but will sacrafise a little low end power to the 100's, but depending on how high you rev 100's will choke your setup if you plan on going past teh stock rev limiter and still pullin. I don't know about the sliencer thing as I never tried it because i like the way my exhaust sounds and I don't want to slience it , but I think that getting your car tuned will def help out a lot. Atleast make a couple log runs and try and tunning that way with your safc2 untill you make it to the dyno.

 

[my98GST]

I don't plan on going past the stock limiter. How much power difference are we talkign about between the 100's and the 200's? But either way the 100's would be a significant improvement over the stockers?

 

[Slippi84]

I don't plan on going past the stock limiter. How much power difference are we talkign about between the 100's and the 200's? But either way the 100's would be a significant improvement over the stockers?

Yeah even the 100's will be night and day from the stock cams. If you don't plan on going past the stock rev limiter go with the 100's they will be better for you overall because you will see faster spool and power will be in the range that you will be operating in most of the time as aposed to to the 200 that shine above the rev limiter where you will never see..

 

[my98GST]

Man I was just looking on SBR's website and Comp claims 20hp with the 100's just putting them in and 35hp over stock with the 200's... Man the 200's are tempting . But jesus they're expensive 400 bucks. Or is that for the set?

What about FP cams? Anyone know anything about them?

 

[98eclipseRS]

why is everyone telling him cams for low end??? Cams will RAISE your power band higher into the rpm range. Yes, folks you read taht right RAISE the power band further into the rev range. Yes you'll get sone mid range increase in power but untill the turbo spools cams aint going to do shit for anyone. It all really depends on how far you want to go with spending money.

Here are some suggestions:
-light weight flywheel, doesn't actually make power but gives superior throttle response and makes the car feel more "torquey"
-Rebuild the engine(2.3L stroker or a 2L with higher comp pistons.)
-Upgrade to a better tunning platform and add timming in the mid range area
-Put on a smaller turbo(not likely going to happen...)
-add a cat to your exhaust

REally you need to get the car tuned and you need to check for boost leaks first. Even untuned the 20g should feel alot faster after only say 3-3.5k rpm not 4.5krpm. It sounds like you ahve a leak somewhere(either boost related or between the head and the turbo). You need to get the car tuned as well it makes a huge difference in performance. Especially if you are running the 550's untuned. In all reality you own a turbo low comp 4cylynder. Low end and big/medium turbo just don't go together. Its just the physics of the way an engine works. Lastly I don't know if you are having a problem with low throttle low end or WOT low end but if its WOT low end stay in a lower gear/launch at a higher rpm, as for cruising around well same thing higher rpms are your friend witha big turbo.

 

[Slippi84]

why is everyone telling him cams for low end??? Cams will RAISE your power band higher into the rpm range. Yes, folks you read taht right RAISE the power band further into the rev range. Yes you'll get sone mid range increase in power but untill the turbo spools cams aint going to do shit for anyone. It all really depends on how far you want to go with spending money.

Here are some suggestions:
-light weight flywheel, doesn't actually make power but gives superior throttle response and makes the car feel more "torquey"
-Rebuild the engine(2.3L stroker or a 2L with higher comp pistons.)
-Upgrade to a better tunning platform and add timming in the mid range area
-Put on a smaller turbo(not likely going to happen...)
-add a cat to your exhaust

REally you need to get the car tuned and you need to check for boost leaks first. Even untuned the 20g should feel alot faster after only say 3-3.5k rpm not 4.5krpm. It sounds like you ahve a leak somewhere(either boost related or between the head and the turbo). You need to get the car tuned as well it makes a huge difference in performance. Especially if you are running the 550's untuned. In all reality you own a turbo low comp 4cylynder. Low end and big/medium turbo just don't go together. Its just the physics of the way an engine works. Lastly I don't know if you are having a problem with low throttle low end or WOT low end but if its WOT low end stay in a lower gear/launch at a higher rpm, as for cruising around well same thing higher rpms are your friend witha big turbo.

We already established that cams slow spool and that a 20g will not have the bottom end power a smaller turbo will but cams like we stated cams make a night and day diffrence over stock cams. WHile I agree that he shoudl be seeing power sooner with a 20g adding a set of 100's will move his power band up but like i said you can retard timing of the exhaust cam and see faster spool and it actualy creates more low end than stockers. It might come on slightly later but when it does the increase it power more than makes up for the slight increase in spool over stock cams. I even have heard from a member that a set of fp2x cams spooled his turbo faster than his stock cams but I hav not seen this for my own eyes so take it for what it's worth yourself. His name is dsm-onster look him up if you wish to ask him yourself.

 

[my98GST]

I do have a few leaks somewhere. I know for one that the BISS screw is leaking and I've got one coming from Machv. The other one..........Well I dunno. I did a test on it and sprayed windex on all of the couplers(fine) bov flange(fine) then sprayed the TB and the biss screw was leaking. Also there was a very loud airy hiss coming from the TB so I sprayed down the TB good with the Windex but it wasn't leaking from anywhere??? The gaskets werent leaking or anything. Anyone got some suggestions? Now that I just rode in my friends EVO with a 75 pill, I'm kind of considering nitrous now . But still for sure doing cams as well.

 

[Splitpi]

I do have a few leaks somewhere. I know for one that the BISS screw is leaking and I've got one coming from Machv. The other one..........Well I dunno. I did a test on it and sprayed windex on all of the couplers(fine) bov flange(fine) then sprayed the TB and the biss screw was leaking. Also there was a very loud airy hiss coming from the TB so I sprayed down the TB good with the Windex but it wasn't leaking from anywhere??? The gaskets werent leaking or anything. Anyone got some suggestions? Now that I just rode in my friends EVO with a 75 pill, I'm kind of considering nitrous now . But still for sure doing cams as well.

Does windex bubble alot? Get a sports bottle fill with water and dish soap. And splash on the area.

 

[my98GST]

Yeah it bubbles pretty good.

 

[98eclipseRS]

Sounds like your throttle body shaft seals are leaking. Nex ttime you do a leak test put you hand around the tb return spring and see if its leaking there.