Does Size Matter?

[SeattleSy#1255]

I'v been kick'n around the idea of builds...one of the things that seems to be a big misconception is turbo size. I think Phil is a good example of what a truck can do with a small/average size turbo assuming it is tuned well. What I am curious about is what would be the advantage of a bigger turbo? More top end? I guess i'm just thinking and talking turbo sizes and wonder what the advantage of going with a smaller turbo is over a bigger after you forked over the money for a forged build. I know driveability may be one pro of the smaller turbo.

Hopefully Green will catch this and chime in...

I don't know just think'n.................

 

[Stangbeater]

Re: Does Size Matter?

I think you should bring your truck back to NY, then we can work on a good combo. Dig also uses a small turbo. 20g hybrid and runs high 11's.

 

[SeattleSy#1255]

Re: Does Size Matter?

let me tell you...it would be here tomarrow if I had a garage for it...i just can't justify letting it sit out in a parking lot through a Rochester, NY winter...i'd rather not have it and know it is put away and safe than have it and leave it out to get pounded on.

I wish i had the truck here, i'd be out with you guys all the time...just no place to store it and i can't afford a storage shed just to let it sit in.

 

[Turbo6]

Re: Does Size Matter?

The key is having the right combination of parts that work well together. If the the cam is huge you will need a converter to work with it. Do your build around the cam/heads because they are the most difficult to change. I did some experimenting with the stock motor with th 52 and 67 turbos. The 52 would get the quickest et but the 67 would run 2 mph faster in the 1/8 and spool was much slower with the 67. The 52 was just the perfect turbo for the stock motor. Now I have a motor with a 415 comp cam and vortecs and just slapped on the 67 turbo and it behaves like the 52 and stock motor but much more power. Would it pick up et with a 72? maybe....mph? yes. Just remember the balance of parts is much more important than any single part. Its not real hard just put on some good vortecs and a 415 cam and 67 turbo with a 3500 stall and hang on! and yes I have a chip available for that combo 10's should be easy at 20 psi with that combo

 

[SeattleSy#1255]

Re: Does Size Matter?

The key is having the right combination of parts that work well together. If the the cam is huge you will need a converter to work with it. Do your build around the cam/heads because they are the most difficult to change. I did some experimenting with the stock motor with th 52 and 67 turbos. The 52 would get the quickest et but the 67 would run 2 mph faster in the 1/8 and spool was much slower with the 67. The 52 was just the perfect turbo for the stock motor. Now I have a motor with a 415 comp cam and vortecs and just slapped on the 67 turbo and it behaves like the 52 and stock motor but much more power. Would it pick up et with a 72? maybe....mph? yes. Just remember the balance of parts is much more important than any single part. Its not real hard just put on some good vortecs and a 415 cam and 67 turbo with a 3500 stall and hang on! and yes I have a chip available for that combo 10's should be easy at 20 psi with that combo

great adive phil...thanks.

 

[syco 2]

Re: Does Size Matter?

Its not real hard just put on some good vortecs and a 415 cam and 67 turbo with a 3500 stall and hang on! and yes I have a chip available for that combo 10's should be easy at 20 psi with that combo[/QUOTE]
i dont know why but i got really happy when u said that

 

[PPI Typhoon]

Re: Does Size Matter?

Yeah, this is a good post. I've been contemplating stepping down from the 76 into a smaller more streetable turbo. I was caught up with the size, but it does seem quite possible to go fast with something smaller, which would of course spool faster.

 

[SeattleSy#1255]

Re: Does Size Matter?

Yeah, this is a good post. I've been contemplating stepping down from the 76 into a smaller more streetable turbo. I was caught up with the size, but it does seem quite possible to go fast with something smaller, which would of course spool faster.

Dan tell me what you are experiencing and your setup (cam, heads, etc)...what do you mean by more streatable, what is so bad about it, lag? high stall converter? This is what i'm looking for, experience from guys like you and phil who have gone through this.

 

[PPI Typhoon]

Re: Does Size Matter?

Dan tell me what you are experiencing and your setup (cam, heads, etc)...what do you mean by more streatable, what is so bad about it, lag? high stall converter? This is what i'm looking for, experience from guys like you and phil who have gone through this.

Well I'm a bad example. I haven't finished by build yet. I won't be making up my mind until I get the new motor in (422 cam, Vortecs, forged). I am just saying that with all of these posts like this, it's making me think that the 76 won't be very fun on the street.

I could be wrong though..... we'll see.

 

[cloneman315]

Re: Does Size Matter?

hopefully 10s id be happy ,jeff stangbeater had a nice new 3 stall garage hit em up for storage

 

[SeattleSy#1255]

Re: Does Size Matter?

hopefully 10s id be happy ,jeff stangbeater had a nice new 3 stall garage hit em up for storage

that would be really nice, but i can't ask that of him or anyone else, i'd feel pretty guilty. If I could work out something to pay someone I would, but it couldn't be much or i'd just get a storage shed for myself. good idea, but i can't ask that of you guys over here.

 

[Stangbeater]

Re: Does Size Matter?

My garage is a bit off from storing any Syclones. I still have to finish the rest of thr house and put in the electric and radiant floor heat in the garage. Also need to get the doors put in and pore the floor. We are a few months out from moving in.I have owned my Syclone since 1998 and have yet to be able to store my Syclone some place inside that I own. It use to sit out side under a cover for the 6 months of winter that we have here in NY. Now it is at a friends house in a barn, and getting shit on by birds and cats jumping on it.

Some day.

 

[smeagol]

Re: Does Size Matter?

What Phil said.

It's all about balance. A larger turbo may offer more peak hp, but you may lose some bottom end/responsiveness. Considering that most Syty motors have horrible airflow, with low RPM operation... it's better to err on the too small side IMO. Getting back to that balance, it's all in the combination. Stock heads, stock cam... something near stock turbo performance is going to be the best selection. Yes you can run a 67, or 72 on a stock motor, but you will have a laggy beast that probably won't break any records. Go smaller on the turbo, and you'll gain back responsiveness and not lose any top end power. The 20g out of the box, IMO, is just a bit laggy for my likes, on a stock motor. At least with the 14cm2 housing. 10-12cm2 housing is a different story. Then that turbo will put a smile on your face. Comparable to a 44 or so, with the right exhaust housing. With that said, I think the PTE housing is a *bit* big for most stock trucks. It works out well with a truck that has headwork and a cam. They don't offer any other options, and that really limits the turbo selections. Once you can flow more air, like Phil's motor does, you have to step up your turbo sizing. Like he said, he might gain MPH, but slow down ET wise, because the setup just wasn't responsive enough. I've seen trucks that could spool the motor fine on the line, but because the turbo was too big, it wouldn't make full boost til 3rd gear. That will make for a slow 60' and 1/8th time, but higher MPH numbers.

So if you are just building a STRONG motor... look at smaller turbos. If you are going to build a motor that flows more air and is stronger, then look at the larger turbos. Size appropriately for your goals. Forged, 422 cam, high flow Vortec heads and you are doing Silver State runs for top MPH - go with a 72 as responsiveness doesn't really matter. Same combination, and you are driving it on the street and drag racing... 63-67, for better low end response.

 

[Jimmy]

Re: Does Size Matter?

What Phil said.

It's all about balance. A larger turbo may offer more peak hp, but you may lose some bottom end/responsiveness. Considering that most Syty motors have horrible airflow, with low RPM operation... it's better to err on the too small side IMO. Getting back to that balance, it's all in the combination. Stock heads, stock cam... something near stock turbo performance is going to be the best selection. Yes you can run a 67, or 72 on a stock motor, but you will have a laggy beast that probably won't break any records. Go smaller on the turbo, and you'll gain back responsiveness and not lose any top end power. The 20g out of the box, IMO, is just a bit laggy for my likes, on a stock motor. At least with the 14cm2 housing. 10-12cm2 housing is a different story. Then that turbo will put a smile on your face. Comparable to a 44 or so, with the right exhaust housing. With that said, I think the PTE housing is a *bit* big for most stock trucks. It works out well with a truck that has headwork and a cam. They don't offer any other options, and that really limits the turbo selections. Once you can flow more air, like Phil's motor does, you have to step up your turbo sizing. Like he said, he might gain MPH, but slow down ET wise, because the setup just wasn't responsive enough. I've seen trucks that could spool the motor fine on the line, but because the turbo was too big, it wouldn't make full boost til 3rd gear. That will make for a slow 60' and 1/8th time, but higher MPH numbers.

So if you are just building a STRONG motor... look at smaller turbos. If you are going to build a motor that flows more air and is stronger, then look at the larger turbos. Size appropriately for your goals. Forged, 422 cam, high flow Vortec heads and you are doing Silver State runs for top MPH - go with a 72 as responsiveness doesn't really matter. Same combination, and you are driving it on the street and drag racing... 63-67, for better low end response.

You need to post more often,BG.

 

[sean]

Re: Does Size Matter?

what turbo would go good with 30 over forged internals vortecs. i was thinking of gt35r with a 415 cam or 422. right know i have a t66 or should i keep it?

 

[Turbo6]

Re: Does Size Matter?

what turbo would go good with 30 over forged internals vortecs. i was thinking of gt35r with a 415 cam or 422. right know i have a t66 or should i keep it?

I would try the 66 first....its not hard to change later.

 

[SY2455]

Re: Does Size Matter?

The key is having the right combination of parts that work well together. If the the cam is huge you will need a converter to work with it. Do your build around the cam/heads because they are the most difficult to change. I did some experimenting with the stock motor with th 52 and 67 turbos. The 52 would get the quickest et but the 67 would run 2 mph faster in the 1/8 and spool was much slower with the 67. The 52 was just the perfect turbo for the stock motor. Now I have a motor with a 415 comp cam and vortecs and just slapped on the 67 turbo and it behaves like the 52 and stock motor but much more power. Would it pick up et with a 72? maybe....mph? yes. Just remember the balance of parts is much more important than any single part. Its not real hard just put on some good vortecs and a 415 cam and 67 turbo with a 3500 stall and hang on! and yes I have a chip available for that combo 10's should be easy at 20 psi with that combo

If I might ask 2 questions to extend this a little further. At what point do you go to a BB turbo, do to the fact that they spool faster? Or are all these larger turbos BB?

 

[0966Sy]

Re: Does Size Matter?

The key is having the right combination of parts that work well together. If the the cam is huge you will need a converter to work with it. Do your build around the cam/heads because they are the most difficult to change. I did some experimenting with the stock motor with th 52 and 67 turbos. The 52 would get the quickest et but the 67 would run 2 mph faster in the 1/8 and spool was much slower with the 67. The 52 was just the perfect turbo for the stock motor. Now I have a motor with a 415 comp cam and vortecs and just slapped on the 67 turbo and it behaves like the 52 and stock motor but much more power. Would it pick up et with a 72? maybe....mph? yes. Just remember the balance of parts is much more important than any single part. Its not real hard just put on some good vortecs and a 415 cam and 67 turbo with a 3500 stall and hang on! and yes I have a chip available for that combo 10's should be easy at 20 psi with that combo

Phil, Why such a high stall speed? I thought you are running a BB 67, I could see having to use the 3500 TC with a big shaft 67 for spool on launchs. Not trying to say your doing it wrong or nothin like that just bringing up a good point IMO. But with the BB turbo's these things are wild and will start producing boost at a very low RPM. Leaving the line at the track at 3500 RPM with 10psi and getting it to hook is a very violent combo, but on the street it's a differant game. Cruising around town with a 3500 TC is not in my future goals with my truck. Alot of people expect a reliable daily driver that is easy on gas and not to hard on the transmission and motor when cruising for any extent of time or daily comute. Is what im trying to get across is with a BB turbo that produces boost at lets say 1800-2200rpm why use the 3500 TC instead of a 2200-2500 TC. You could have boost at 1800rpm to lets say 5500rpm instead of 3500rpm to 5500rpm, making power more throughout the motor's powerband. Making a light throttle torque packing monster for the street and strip. also this would be easier on the Transmission and motor becuase the lower stall speed for long periods of time cruising or road trips(Nats).

So Phil what i'd like to ask is what dissadvantages would you see with using a 2500 stall TC in your build? I havent road in or used a BB turbo before but i understand it takes a load on the motor to spool a turbo. So with the 3500 TC what kinda RPM does your truck begin to build boost?

I guess it's up to the persons expectations for the truck, being strictly strip or street and strip.

 

[Turbo6]

Re: Does Size Matter?

Phil, Why such a high stall speed? I thought you are running a BB 67, I could see having to use the 3500 TC with a big shaft 67 for spool on launchs. Not trying to say your doing it wrong or nothin like that just bringing up a good point IMO. But with the BB turbo's these things are wild and will start producing boost at a very low RPM. Leaving the line at the track at 3500 RPM with 10psi and getting it to hook is a very violent combo, but on the street it's a differant game. Cruising around town with a 3500 TC is not in my future goals with my truck. Alot of people expect a reliable daily driver that is easy on gas and not to hard on the transmission and motor when cruising for any extent of time or daily comute. Is what im trying to get across is with a BB turbo that produces boost at lets say 1800-2200rpm why use the 3500 TC instead of a 2200-2500 TC. You could have boost at 1800rpm to lets say 5500rpm instead of 3500rpm to 5500rpm, making power more throughout the motor's powerband. Making a light throttle torque packing monster for the street and strip. also this would be easier on the Transmission and motor becuase the lower stall speed for long periods of time cruising or road trips(Nats).

So Phil what i'd like to ask is what dissadvantages would you see with using a 2500 stall TC in your build? I havent road in or used a BB turbo before but i understand it takes a load on the motor to spool a turbo. So with the 3500 TC what kinda RPM does your truck begin to build boost?

I guess it's up to the persons expectations for the truck, being strictly strip or street and strip.

I dont have a BB turbo. I have never tried a different stall because this converter was in the truck when I bought it and it has always done great, even with the stock motor. It drives around really nice in fact you dont really notice it.

 

[nightdiver]

Re: Does Size Matter?

I had a P trim T68 with a .84 a/r a few years ago with a 2800 stall and i loved it. Anything more than 3000K stall will hurt low rpm torque