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Design 1 Systems Turbo Kit for a Pushrod 3.4L? by project34
Started on: 11-11-2007 12:23 PM
Replies: 18
Last post by: AutoTech on 11-12-2007 08:23 PM
project34
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Report this Post11-11-2007 12:23 PM Click Here to See the Profile for project34Send a Private Message to project34Direct Link to This Post
The Design 1 Systems turbo kit consistently seems to get rave reviews from its users on Pennock's Fiero Forum, but its recent, substantial, unannounced price hike, and its below-average customer service responses understandably don't get rave reviews: http://www.fiero.nl/forum/Forum1/HTML/068156.html

Nevertheless, I'm considering the purchase of a Design 1 Systems "Stage One" turbo kit for my recently completed, essentially all-new pushrod 3.4L engine, primarily because the Design 1 "Stage One" turbo kit has had such good reviews by its users.

Unfortunately, despite two earlier attempts in September and October, I've received no reply from Design 1 Systems re the following question which I've submitted to Design 1 Systems using their e-mail form they request you use for questions:

I swapped my Fiero's 60-degree, pushrod 2.8L engine for what essentially is a freshly bored 0.040'-over, "all-new" 60-degree, pushrod 3.4L engine (all-new including even a new GM crank and new GM rods). With your Stage 1 kit for automatic-equipped Fieros, and no intercooler, what boost and compression ratio do you gentlemen recommend for this 3.4L "daily driver" using premium pump gas (92-93 octane)?

  • Can you on Pennock's Fiero Forum answer my question, or do you feel I simply should have provided Design 1 Systems more information? If the latter, what specific additional information do you feel I should have provided Design 1 Systems to get my question answered?

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Report this Post11-11-2007 03:13 PM Click Here to See the Profile for AquaHuskyClick Here to Email AquaHuskySend a Private Message to AquaHuskyDirect Link to This Post
With aluminum heads, I do believe you can safely run 9 - 9.5 to 1 comp ratio at a safe 8 PSI without harm with 92-93 test fuel.
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project34
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Report this Post11-11-2007 04:02 PM Click Here to See the Profile for project34Send a Private Message to project34Direct Link to This Post
 
quote
Originally posted by AquaHusky:

With aluminum heads, I do believe you can safely run 9 - 9.5 to 1 comp ratio at a safe 8 PSI without harm with 92-93 test fuel.

Thanks for the response, but I don't have aluminum heads.

My 3.4L Fiero engine swap was sourced from an iron-headed, 3.4L, 1995 Camaro.

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Report this Post11-11-2007 05:20 PM Click Here to See the Profile for Team Race-TechSend a Private Message to Team Race-TechDirect Link to This Post
I agree with AquaHusky. If your going to run the cast heads thats great, 7-8 psi non-intercooled is okay. But I would stronly recomend running a 7730 PCM with a knock sensor. This way your making it all safe and if you ever considering water injection and upping the boost to 10 psi it all will work out for the best I think. good luck with your build, or have you considered making your own kit??

Joe

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e-mail: joetrentadue@hotmail.com

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Dennis LaGrua
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Report this Post11-11-2007 05:28 PM Click Here to See the Profile for Dennis LaGruaClick Here to Email Dennis LaGruaSend a Private Message to Dennis LaGruaDirect Link to This Post
Beware . The Design One turbo kits do not work well on the 3.4L. I tried to deal with them a few years back , before I did my own kit and the tech support and customer service was absolutely terrible. They ended up sticking me for $1000 which is something that I will remember.. I wouldn't advise using anything from Design One unless you want to get the shaft! They are the lowest. The absolute bottom of the barrel!

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Report this Post11-11-2007 05:45 PM Click Here to See the Profile for AutoTechClick Here to Email AutoTechSend a Private Message to AutoTechDirect Link to This Post
I have to agree on the customer support, or lack thereof. However, it is a rock solid kit.

The only issue I am concerned about using the D1 on the 3.4l is the turbo. The RHB5 supplied in the kit is just barely in the proper efficiency range for the 2.8l. A bigger displacement engine certainly will make this worse. I would suggest finding a bigger unit that will be a direct replacement so that no flange changes are neccessary. This is what Im in the proccess of doing right now. I found a bigger compressor housing and wheel here , but Im not positive if its going to work.

[This message has been edited by AutoTech (edited 11-11-2007).]

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Report this Post11-11-2007 05:56 PM Click Here to See the Profile for AquaHuskyClick Here to Email AquaHuskySend a Private Message to AquaHuskyDirect Link to This Post
 
quote
Originally posted by Team Race-Tech:

I agree with AquaHusky. If your going to run the cast heads thats great, 7-8 psi non-intercooled is okay. But I would stronly recomend running a 7730 PCM with a knock sensor.
Joe



Remember tho, iron heads need lower C.R. at the same PSI as compared to aluminum heads because of heat transfur. Iron heads I would recommend 8.2-8.5 C.R. to be safe. Any higher and I'd suspect you'd end up with Swiss cheese pistons.
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Report this Post11-11-2007 07:57 PM Click Here to See the Profile for project34Send a Private Message to project34Direct Link to This Post
 
quote
Originally posted by Team Race-Tech:
I agree with AquaHusky. If your going to run the cast heads thats great, 7-8 psi non-intercooled is okay. But I would stronly recomend running a 7730 PCM with a knock sensor. This way your making it all safe and if you ever considering water injection and upping the boost to 10 psi it all will work out for the best I think. good luck with your build, or have you considered making your own kit??
Joe

Joe, it's a small world. The iron V6 heads I plan on usiing are the same ported iron V6 heads that I purchased from you in 2004, when the company you had in Canada was called either "The Fiero Shop" or "Race-Tech Automotive."

Your 7730 ECU and knock sensor suggestions seem a good idea.

Separately, despite your comments and AquaHusky's, I don't know of an easy way to run aluminum heads on the pushrod 3.4L V6 block which I have, and which is sourced from a `95 Camaro. I'm not aware of one, but if there is an easy way to run aluminum heads on that engine block, I'm certainly open to that suggestion.

As I mentioned at the outset of this thread, my Fiero is a "daily driver," so the 7-8 pounds of boost you suggest is fine. However, please remember that I'm also seeking a recommendation on a safe compression ratio for such a turbocharged, "daily driver" engine.

Dennis, I couldn't agree more with your assertion about the poor customer service from Design 1 Systems:
 
quote
Originally posted by Dennis LaGrua:
I tried to deal with them a few years back , before I did my own kit and the tech support and customer service was absolutely terrible.

It's because of that poor customer service that I raised the straightforward questions I did at the start of this thread, unanswered by Design 1 Systems. The only reason I'm even pursuing the idea of a Design 1 Systems turbo kit for my 3.4L swap is that it's enjoyed rave reviews on Pennock's for the 2.8L. However, your straightforward comment below causes me to question my supposition that their turbo also would work well on my 3.4L:
 
quote
Originally posted by Dennis LaGrua:
Beware . The Design One turbo kits do not work well on the 3.4L.

I don't dispute your assertion; I'm simply seeking clarification regarding it. Are you referring to the moderate, lower-boost, "Stage One" system that I'm interested in, or to their higher-boost "Stage Two" system? I realize you're not in the business of selling pushrod 3.4L turbo kits anymore, but I'd really appreciate your opinions, Dennis.

AutoTech, yours is an interesting point re that turbo and the engine's size:
 
quote
Originally posted by AutoTech:
I have to agree on the customer support, or lack thereof. However, it is a rock solid kit.
The only issue I am concerned about using the D1 on the 3.4l is the turbo. The RHB5 supplied in the kit is just barely in the proper efficiency range for the 2.8l. A bigger displacement engine certainly will make this worse.

The same turbo in a 3.4L engine, roughly 20% larger than the one that turbo was designed for (a 2.8L), could indeed be an issue. My car, however, will be an unraced, "daily driver." Do you feel the turbo's size (or perhaps more accurately, lack thereof) would still be an issue?

As I'd indicated at the outset of this thread, my 3.4L engine is as "new" and "bulletproof" as any will ever be, so I'm not particularly worried about it handling a turbo. However, you collectively are starting to concern me that maybe my all-new 3.4L engine swap (as opposed to the tired 2.8L it replaced) shouldn't attempt to handle a Design 1 Systems "Stage One" turbo.

Please keep your ideas coming. They've been very helpful.
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Report this Post11-11-2007 08:41 PM Click Here to See the Profile for AutoTechClick Here to Email AutoTechSend a Private Message to AutoTechDirect Link to This Post
 
quote
Originally posted by project34:

The same turbo in a 3.4L engine, roughly 20% larger than the one that turbo was designed for (a 2.8L), could indeed be an issue. My car, however, will be an unraced, "daily driver." Do you feel the turbo's size (or perhaps more accurately, lack thereof) would still be an issue?



Actually the turbo was designed for the Thunderbirds 2.3l 4cyl, or at least thats what it was used for. Im not sure if youve ever seen this thing, but it is VERY tiny.

The point is, the more you decrease the turbos efficiency, the more the intake air charge temperature will increase. I wouldnt be surprised if the temps got to over 200*F. The hotter the charge, the less dense the air and a higher chance of detonation. It doesnt matter how new your engine is, detonation will destroy anything if it is prolonged.

Honestly, if you keep the boost down to 6-7psi max, I dont see any real threat. If I were you I would at least look into that bigger housing/wheel I showed you ealier. For $150 I think its worth it, you will most likely see an increase in HP, lower EGT's, and you would be able to safely increase boost pressure.

You are using at least 17lb injectors correct?

[This message has been edited by AutoTech (edited 11-11-2007).]

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Report this Post11-11-2007 08:49 PM Click Here to See the Profile for Doc JohnSend a Private Message to Doc JohnDirect Link to This Post
Here are a few more ideas to play with. I had the Miller-Woods (same as the Design 1) turbo in my cars for many years. It was installed by Jim Sutter of IRM, who had a hand in designing the MW system. I remember Jim telling me that the boost on the Stage I and Stage II versions were the same, 10lbs. This was for the MW version, maybe D1S has reworked it a little. Jim advised customers that they only needed the Stage II system (which adds a knock sensor and a computer from an '85 Fiero) if they were operating the turbo in "extreme" climates, either hot or cold. I ran mine as a Stage I system for a couple of years and had no issues.

Jim was certain that the turbo system would work just fine with a 3.1 l engine. For a short time, he was working with Jasper Engine rebuilders to produce a 3.1 rebuild to a Fiero 2.8 block that was optimized for the MW turbo (this set up required the the Stage II system). To my knowledge, Jim never got around to building a 3.4 engine with this turbo before IRM faded away.
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Report this Post11-11-2007 08:54 PM Click Here to See the Profile for AutoTechClick Here to Email AutoTechSend a Private Message to AutoTechDirect Link to This Post
 
quote
Originally posted by Doc John:

I ran mine as a Stage I system for a couple of years and had no issues.



What made you add the knock sensor, and did you switch to an 85 ECM?
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Report this Post11-11-2007 09:16 PM Click Here to See the Profile for Doc JohnSend a Private Message to Doc JohnDirect Link to This Post
 
quote
Originally posted by AutoTech:


What made you add the knock sensor, and did you switch to an 85 ECM?


At one time I was considering going to the 3.1 block for more power. So I upgraded to the Stage II system anticipating the reworked engine (my plans changed over the years, and the size of my dream engine grew to 6.0 l).

Yep, I did switch to the '85 ECM (included with the Stage II upgrade). IIRC, the '85 ECM is the only V6 Fiero ECM that has a provision for a knock sensor. I really could't determine if there were any performance gains going from Stage I to Stage II (never dynoed either one of them). The max boost remained the same in both systems, 10lbs.

Edit to add: My butt dyno did notice a difference when I added a set of Darrell Morse parts - enlarged throttle body and ported upper/middle/lower manifold set. It seemed to get into the power zone a little faster; I don't know if it added peak HP but it DID make it more responsive.

[This message has been edited by Doc John (edited 11-11-2007).]

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Report this Post11-11-2007 09:32 PM Click Here to See the Profile for AutoTechClick Here to Email AutoTechSend a Private Message to AutoTechDirect Link to This Post
Ok, I was just wondering if you were having timing issues. Im also at 10psi as you were with no knock sensor (other than my ears), and Im not having any problems.

I think upgrading to the 1227749 ECM would also be a very smart move. It is has more tuning options, which is ideal on a force fed application, and it also uses a knock sensor.

[This message has been edited by AutoTech (edited 11-11-2007).]

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Report this Post11-12-2007 08:49 AM Click Here to See the Profile for project34Send a Private Message to project34Direct Link to This Post
 
quote
Originally posted by AutoTech:
Actually the turbo was designed for the Thunderbirds 2.3l 4cyl, or at least thats what it was used for. Im not sure if youve ever seen this thing, but it is VERY tiny.
No, I've not seen the size of that turbo. I'd assumed (apparently erroneously) that it was based on the highly-respected Miller-Woods turbo, which in turn I'd thought was built for the pushrod 2.8L engine. If that turbo actually was designed for a 2.3L engine, one only (2.3L/3.4L =) 68% the size of my 3.4L engine swap, that doesn't inspire confidence in the idea of transplanting it into my 3.4L engine.

 
quote
Originally posted by AutoTech:
The point is, the more you decrease the turbos efficiency, the more the intake air charge temperature will increase. I wouldnt be surprised if the temps got to over 200*F. The hotter the charge, the less dense the air and a higher chance of detonation. It doesnt matter how new your engine is, detonation will destroy anything if it is prolonged.
Your points all make sense to me.

 
quote
Originally posted by AutoTech:
You are using at least 17lb injectors correct?
Yes, I am currently using 17-pound injectors with my 3.4L swap. I've no objection to using larger injectors if warranted by the addition of a turbo, because I've zero interest in risking an essentially all-new engine by running it too lean under boost.

 
quote
Originally posted by AutoTech:
Honestly, if you keep the boost down to 6-7psi max, I dont see any real threat.
My Fiero has to be a year-round, "daily driver" and it won't be raced, so I've no problem with keeping the boost that low. For my 3.4L, what compression ratio would you recommend with that amount of non-intercooled boost and the 92/93 octane available to me?



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Report this Post11-12-2007 09:06 AM Click Here to See the Profile for timgrayClick Here to visit timgray's HomePageClick Here to Email timgraySend a Private Message to timgrayDirect Link to This Post
I also would NOT get the design 1 kit. they refuse to answer any pre-sale questions. Which is a huge red flag in buying anything.

And for the price and what you are doing it will not be easier than building your own turbo kit, their chip will be useless to you (it's for a 2.8 NOT a 3.4) so you will have to spend more $$$ on custom tuning.

I found that if you go looking for a decent hotrod muffler shop you can get all your custom pipes done for FAR cheaper than design 1 can. AND you can buy a correct turbo for a 3.4 instead of the design 1 turbo sized for a 2.8.

I found I can have pipes made for me to basically create that stage 1 kit for less than 1/3 the price they charge and that is WITH a turbo. getting it tuned is still more cost but I guarantee that even with the design 1 kit you will still need it tuned on a 3.4. Also spending that kind of money with a company that refuses to return emails, phone calls or even talk to a guy that had cash in hand ready to buy..... that means you do not want to deal with them. as that is the same service you will get after the sale.
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Report this Post11-12-2007 09:16 AM Click Here to See the Profile for Joseph UpsonClick Here to Email Joseph UpsonSend a Private Message to Joseph UpsonDirect Link to This Post
 
quote
Originally posted by AutoTech:

Ok, I was just wondering if you were having timing issues. Im also at 10psi as you were with no knock sensor (other than my ears), and Im not having any problems.

I think upgrading to the 1227749 ECM would also be a very smart move. It is has more tuning options, which is ideal on a force fed application, and it also uses a knock sensor.



The problem with the 749 ECM is that the closest boosted tune for a start is for a 4.3L engine whereas for the 730 it's 3.1. That could make tuning a real challenge since you would be trying to scale down a good bit instead of small adjustments here and there with a tune closer in displacement to what you are working with. It maybe possible to get an excellent head start by calculating the appropriate injector size for the same condition on the smaller engine. For example the Turbo 3.1 uses ~23 lb/hr injectors, the naturally aspirated 3.1 uses 16 lb/hr injectors, you could swap the engines around without a problem as long as the injectors stayed with their perspective computer tunes. You would choose an injector flow rate based on the difference in the engine displacement, for example if you moved up from the 3.1 to the 3400 aluminum head engine you could probably be pretty close on tune by increasing the injector flow rate by about 2 lb/hr or whatever the cu in. to flow rate ratio indicates for a start.

[This message has been edited by Joseph Upson (edited 11-12-2007).]

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Report this Post11-12-2007 01:22 PM Click Here to See the Profile for lou_diasClick Here to Email lou_diasSend a Private Message to lou_diasDirect Link to This Post
Hmmm.... I have 19#'s in my turbo 3.1 with a K26 KKK turbo.
In about a month, I want to replace the heads with ported ones and port the stock intake and get a DM 57 mm throttle body. I also need the cross-over rewelded to eliminate a leak where it mates to the back manifold. There is also a leak where one of the heads meets one of the exhaust primaries. The head dry-rotted and the bolt just spins in place. Luckily, I have a spare set of heads that can be ported.

I was thinking of looking for some bigger injectors as well. The boost is set to max at 8psi but the turbo supports 16 but my fuel is limited to 12 psi max. I'm probably safe with the 19# injectors if I never go past 10psi.

The car needs a fuel pump now. Any recommendations? I also have an 85 ecm that I want to swap in to eliminate the Buick ESC module.

I'm looking to run 10psi. That should get me about 210rwhp - no?
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Report this Post11-12-2007 06:06 PM Click Here to See the Profile for project34Send a Private Message to project34Direct Link to This Post
 
quote
Originally posted by timgray:

I also would NOT get the design 1 kit. they refuse to answer any pre-sale questions. Which is a huge red flag in buying anything.

And for the price and what you are doing it will not be easier than building your own turbo kit, their chip will be useless to you (it's for a 2.8 NOT a 3.4) so you will have to spend more $$$ on custom tuning.

I found that if you go looking for a decent hotrod muffler shop you can get all your custom pipes done for FAR cheaper than design 1 can. AND you can buy a correct turbo for a 3.4 instead of the design 1 turbo sized for a 2.8.

I found I can have pipes made for me to basically create that stage 1 kit for less than 1/3 the price they charge and that is WITH a turbo. getting it tuned is still more cost but I guarantee that even with the design 1 kit you will still need it tuned on a 3.4. Also spending that kind of money with a company that refuses to return emails, phone calls or even talk to a guy that had cash in hand ready to buy..... that means you do not want to deal with them. as that is the same service you will get after the sale.

You raise some good points, timgray. My rationale for considering the Design 1 Systems turbo kit for my 3.4L was based on the assumption that the kit would make a turbo installation on my 3.4L much easier. It sounds like you feel that may be true for a 2.8L engine, but it won't be true for a 3.4L engine swap.

Incidentally, your comments about the poor, pre-sale customer service gave me a chuckle (unintentionally, I'm sure). I found the pre-sale customer service so-o-o-o bad (as have others), that I thought it actually kind of funny. In fact, as I mentioned earlier, I started this thread because of that poor customer service, deciding I may have better luck atempting to get my questions answered here, via Pennock's Fiero Forum, than through Design 1 Systems.

Similarly, the unannounced and apparently quite substantial price hikes that were absent from Design 1 Systems' outdated website, which TommyT913 mentioned in another thread, also don't inspire confidence. (Check out the thread, "Is Design 1 Systems still in business?" accessible via this link: http://www.fiero.nl/forum/Forum1/HTML/068156.html )

Like you, timgray, Dennis LaGrua doesn't have a high opinion of this turbo kit for the 3.4L engine, either:
 
quote
Originally posted by Dennis LaGrua:
Beware . The Design One turbo kits do not work well on the 3.4L. I tried to deal with them a few years back , before I did my own kit and the tech support and customer service was absolutely terrible.

AutoTech also seems to have reservations about Design 1 Systems' turbo, that it's somewhat undersized for a 3.4L --- even for a street application like mine.

Is the consensus basically that the Design 1 Systems turbo and chip may be fine for a 2.8L Fiero engine, but that they're both less than adequate for the 3.4L engine swap? (They seem to get rave reviews for 2.8L engines.)
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Report this Post11-12-2007 08:23 PM Click Here to See the Profile for AutoTechClick Here to Email AutoTechSend a Private Message to AutoTechDirect Link to This Post
 
quote
Originally posted by project34:

Is the consensus basically that the Design 1 Systems turbo and chip may be fine for a 2.8L Fiero engine, but that they're both less than adequate for the 3.4L engine swap? (They seem to get rave reviews for 2.8L engines.)


Statistically, yes, the turbo is to small. However, since you are not interested in raising the boost past 6-7psi, the turbo is not going to be spooled drastically past a reasonable efficiency percentage. I think 9+ psi is where you are going to get very poor efficiency, in other words, the air charge will be "super-heated". Again, for your application, I would not be concerned.

Since you are somewhat limited to low boost pressure, I would think about putting in a little higher comp. piston to increase the HP even further. 9 - 9.5:1 would be tops. For a daily driver, 8.5 is fine as well.


Now as far as the D1 chip is concerned, I believe it will work sufficiently. Joseph Upson made a good point ealier in this thread when we were talking about the 749/730 ECMs. The most important concern in this situation is the injector size. The D1 is tuned using the stock Fiero injector size. So long as the flow rate ratio of the 3.4l/17lb are close to the 2.8l/15lb, the tune should still be well withing reasonable limits.
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