turbo 3v throttle body questions

[v8venomgt]

just curious what others are running for a throttle body and how your drivability is. im running a thp single kit, and im currently using the oem throttle body. under cold motor conditions, driveability is rough. it seems to choke, buck and surge really bad under initial start up if you slowly release the clutch with no throttle applied (using just the friction point to get moving). if throttle is applied, it doesnt seem to do anything at all. it doesnt sound like its pinging, or back firing, just very rough.

one source suggested with the increased piping (both in diameter and plumbing)there is a bottleneck at the oem throttle body causing problems under intial start up-to warm engine temp. they mentioned the twin set up may be causing issues and a large single tb may help clear it up.

also the car hesitates getting in to boost under part throttle situations particularly in lower gears, it stumbles into boost if that makes sense. wot there is no issue, and makes great power. ive data logged it, and it shows when its stumbling into boost, and im trying to get moving under cold conditions, the car is pulling timing, but seems ok under WOT. ive also noticed there is barely any lowend whatsoever, im not sure if thats associated to the CMDP delete, and the 3.31s in place now. the car just feel sluggish and heavy downlow out of boost. the plugs are new and still look clean, the turbo spins freely, there is no smoking of any kind, or other oddities. all of the clamps look to be in good shape, and its been determined there are no exhaust leaks anywhere.

quick rundown of the car
thp single kit, 61 mm 8# of boost exiting out of a 3 in dynomax catback
hpx slot maf
frpp plugs
no cats
cmdp
60lbs injectors, twin gt supercar pumps
stock tb, plenum, exhaust manifolds, pullies, etc


the car had a lot of issues after install, that have been getting resolved. the whole hotside has been removed and reinstalled since the intitial tune, the turbo has been rebuilt, the exhaust &cmdp went on after the tune (emailed updated tune is in the car now), etc etc. it may just need an updated driveability dynotune which is fine, i just want to be sure that i am not overlooking anything before it goes back on the dyno and if i single blad TB is needed

 

[Jeffs FRC]

Get a good tune... You must have went to a guy that only tunes wot!

Also, you just told me last week the car had an exhaust leak still. Did you just fix it again?

 

[v8venomgt]

Get a good tune... You must have went to a guy that only tunes wot!

Also, you just told me last week the car had an exhaust leak still. Did you just fix it again?

lol......im still confident in mikes ability. what specifically changed, i do not know. however a tune from tim is going to be over $400. to have mike adjust my tune is less then half of that. right now, its either park the car indefinitely/when work picks back up, or try button my scrap up on a shoestring budget. i just got back from VS, they said there are 0 leaks. justin and i pulled the whole hotside and nothing changed. VS said what im hearing is exhaust escape out of the wastegate (dumped to atmosphere to those who dont know) and thats the "leak" that im hearing

 

[Jeffs FRC]

The absolute first thing I would do is get the car retuned on a dyno.

Don't even think about wasting money on a TB. Im not sure who told you the stock TB is a bottleneck and is causing your driveability issues...imo thats BS.

Save some coin and get the car back on the dyno. I bet your in the mid 470's easy.

 

[v8venomgt]

The absolute first thing I would do is get the car retuned on a dyno.

Don't even think about wasting money on a TB. Im not sure who told you the stock TB is a bottleneck and is causing your driveability issues...imo thats BS.

Save some coin and get the car back on the dyno. I bet your in the mid 470's easy.

agreed, in theory it sounds ok but i dont think thats whats causing the pulling of timing. i shot post an email, not long ago. once he has availablity the car will hit the dyno, and maybe i can finally enjoy it without any bullshit associated to it.....id love to see what it can do on the strip, before it sells

 

[GB10]

I have the stock throttle body with none of those issues. Sounds tune related to me. Part throttle and driveability definitely need some attention if you're having those issues. I can't really give you any specifics without a datalog, but I will say I paid $450 the last time my car was tuned and it was worth it, because I've had bad tunes on other vehicles and it was nothing but headaches.

I'm currently switching over to E85, but the $450 was for a 93 pump tune with drivability tuned as well.

 

[v8venomgt]

I have the stock throttle body with none of those issues. Sounds tune related to me. Part throttle and driveability definitely need some attention if you're having those issues. I can't really give you any specifics without a datalog, but I will say I paid $450 the last time my car was tuned and it was worth it, because I've had bad tunes on other vehicles and it was nothing but headaches.

I'm currently switching over to E85, but the $450 was for a 93 pump tune with drivability tuned as well.

it very well may be, but im thinking its more like it needs an updated tune to get everything in sync. the guy that tuned my car has proven his ability with others cars, so i do trust him. the retune fee on his part is a reduced rate of the initial tune. his pricing is in line with others that are local.

 

[GrnBullitt08]

Defintely sounds like a tuning issue. Don't worry about your TB right now. Get the tune worked out

 

[v8venomgt]

Defintely sounds like a tuning issue. Don't worry about your TB right now. Get the tune worked out

i was thinking along similar lines, i just didnt want to go on the dyno, and hear "hey you need this, come back when you have your shit straight"

 

[GrnBullitt08]

Nah, your stock TB flows fine for what you have. Once they get that base tune perfect on the dyno then save up for the block, add more boost add attack the manifold and TB.

Your running delete plates right?

 

[v8venomgt]

Nah, your stock TB flows fine for what you have. Once they get that base tune perfect on the dyno then save up for the block, add more boost add attack the manifold and TB.

Your running delete plates right?

a block is so far down the line......lol but im board with you thinking its just needing to get the base tune perfected

 

[Marc s]

I agree with everyone that your issues are tune related. If you are thinking about a TB for more HP. Last week I installed a FRPP TB on my car. On my pump gas tune we did a base line, installed the new TB, and re-tuned it. I picked up 5whp and 10wtq. On a blow through setup, a bigger TB is not worth it.

 

[v8venomgt]

I agree with everyone that your issues are tune related. If you are thinking about a TB for more HP. Last week I installed a FRPP TB on my car. On my pump gas tune we did a base line, installed the new TB, and re-tuned it. I picked up 5whp and 10wtq. On a blow through setup, a bigger TB is not worth it.

thanks for your insight

 

[retfr8flyr]

I have a GT500 TB on mine but in hindsight I think it was a wast of money with a blow through setup. Your problems are definitely tune related. Turbos are very hard to tune and the cold start and drivability are the hardest part. Where are your O2 sensors located in relation to the distance from the turbo. The O2's need to be as close to the turbo as you can put them so that they get hot enough for the computer to get understandable readings. When the O2's don't get hot enough the computer dumps more fuel into the engine to try and make more power for hotter temps. I have my car running in open loop until the O2's get hot enough for the readings to be reliable. The MAF transfers and open loop tuning have to really good on a turbo setup.


Earl

 

[Fallenauthority]

Definitely sounds like a tune issue. If your tuner didnt get that straight on the dyno the first time I would be looking for another tuner.
I had my car remotely tuned by Lito and it is badass, perfect driveability, no hiccups, stutters or bucking. You should PM him.

 

[s8v4o]

I agree with everyone that your issues are tune related. If you are thinking about a TB for more HP. Last week I installed a FRPP TB on my car. On my pump gas tune we did a base line, installed the new TB, and re-tuned it. I picked up 5whp and 10wtq. On a blow through setup, a bigger TB is not worth it.

EXACTLY! Blow thru setups are less restrictive than draw thru setups. If you had a high HP whipple or something then maybe, but not really necessary for a centri or turbo setup.

 

[white05gt]

EXACTLY! Blow thru setups are less restrictive than draw thru setups. If you had a high HP whipple or something then maybe, but not really necessary for a centri or turbo setup.

I have discussed this several times and people thought I was stupid for running a stock tb with the JPC intake. I was going to do the back to back dyno to prove my point but looks like I don't have to. Thanks Marc

 

[JeremyH]

I agree with everyone that your issues are tune related. If you are thinking about a TB for more HP. Last week I installed a FRPP TB on my car. On my pump gas tune we did a base line, installed the new TB, and re-tuned it. I picked up 5whp and 10wtq. On a blow through setup, a bigger TB is not worth it.

5rwhp and 10rwtq are nice gains for just a tb. What did you expect?

Its a supporting mod.

Now is 5rwhp/10rwtq worth the $500 price tag of a shiny frpp tb, not in my book. You can get a frpp manifold for that price and pick up 20-30rwhp.

But when you can pick up a bbk 62 or gt500 tb for $100-150 in the classifieds.

Is that worth it? Heck yeah imho.

To each thier own.

 

[Fallenauthority]

5rwhp and 10rwtq are nice gains for just a tb. What did you expect?

Its a supporting mod.

Now is 5rwhp/10rwtq worth the $500 price tag of a shiny frpp tb, not in my book. You can get a frpp manifold for that price and pick up 20-30rwhp.

But when you can pick up a bbk 62 or gt500 tb for $100-150 in the classifieds.

Is that worth it? Heck yeah imho.

To each thier own.

That is 5rwhp on a 700hp car, on the average Joe's setup I doubt it would gain 5hp in blow thru setup

 

[white05gt]

That's a .714% increase of hp lol