Rice's 1FZ-FE rebuild Thread (1 Viewer)

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I'm amazed that somebody can just yank out a motor, know what to do for whatever gain, then do it in a timely manner getting almost everything right the first time. More power to you, Rice. But I won't say you make me look bad because none of y'all have any expectation of skills from me:rofl:.

Shhh. Could be a little premature to mention getting it right the first time. Let's just cross our fingers and be diligent to get the details right and we will see.
 
50mm will not supply the volume needed. Not even close. 56mm would be the minimum.

Yeah my 57mm spools way before 3000, I could have full boost by 2200.

In fact I posted some numbers that might make this interesting, let me find them.

Well I didn't find the numbers and this was before my final tune. but you can see we started from 2500rpms and up the turbo was ahead of the stock system. But you can see even with a 57mm turbo it is falling of a little up top.

@2500rpms +10hp +25ft/lbs
@2750rpms +35hp +70ft/lbs
@3000rpms +50hp +140ft/lbs
@3250rpms +95hp + 200ft/lbs
@3500rpms +145hp +245ft/lbs

pre-jpg.950766



Agreed, tuning is always the most difficult part. Plenty of guys with turbos on diesels have trouble tuning their compound setup properly. So many gauges are needed to do it correctly that most people skip a lot of it, then there's always the possibility (if not properly tuned) of having so much backpressure that you choke the engine OR force wastegates to open prematurely.

Tuning issues aside, the big advantage of a compound turbo setup is not the peak HP number (that's not a scientific way to rate a turbo anyway IMHO) but how quickly the boost comes on and how flat boost delivery can be. I doubt that a 58mm turbo on a 4.5l engine can spool before (pulling this out of my ass) 3000RPM. On an engine like the 1FZ, that's past the N/A torque peak and would result in lots of driver-felt turbo lag. With a smaller single you can spool up to 30psi before 2000rpm on a 4.5l motor but not have enough flow for the top end. A well matched and tuned compound setup can deliver plenty of boost throughout the entire RPM range without gross inefficiencies anywhere. In my mind I compare a well-tuned compound setup's boost delivery to that of a supercharger, but with much more intake air density and higher power potential :steer:

Lightweight turbines, compressors and VGT systems can all help the turbo spool faster and not choke as RPMs come up but you're still limited to a static compressor size and therefore map. There's always a compromise to be made and my point is that there are less compromises with a compound setup than with a single turbo, when talking about tuning and engine performance. Plumbing and fitment are more of a pain however.


I realize that my knowledge is in the context of diesel engines, but the concepts are the same, with the exception of how fueling affects combustion temperature (that's inverted between gas and diesel).


Rice should go with a smaller single IMHO, something around 50mm, for the boost levels he wants, to ensure that there isn't a lot of lag. 4500 redline is pretty low for a gas engine so a smaller turbo would serve him better. My 46mm turbo with 6cm2 turbine housing hits 30psi at 2000rpm, so I think the map would be a decent match but rice would want a larger turbine housing, somewhere between 9-12cm2. Unfortunately I don't know how Holset turbine housing dimensions map to Garret turbine housing dimensions, but Garret has that sweet turbine map calculator tool, so Rice can play with that to see where he wants his boost to come on. This is slick as s***:

Garrett Boost Adviser - Online | Turbobygarrett
 
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Question...what are the capabilities of the TRD supercharger typically used on the 80's? Would one of those hold up to compound boost? Back when I used to mess with Mustangs, there were plenty of folks turbo-feeding their factory Eaton M112 supercharged Terminator cars and getting huge power numbers (800-900hp). Feeding a supercharger with a turbo is a game changer, best of both worlds scenario, at least in terms of both low and high-end torque. The compound cars pulled so hard off the line whereas the regular turbo cars would lose traction halfway down the track.

 
If you were trying to get 1400hp out of your setup, maybe it would be worth the hassle, but on the size of turbo we are talking about lag is not an issue. You really don't notice any lag on my system, the only slight "lag" you might see if before the torque converter comes up on stall at like 1800rpms. These are not 3L spupras with 90mm turbos, we are talking about a 4.5L truck with a small turbo, really spool is not a factor at these power levels.

Question...what are the capabilities of the TRD supercharger typically used on the 80's? Would one of those hold up to compound boost? Back when I used to mess with Mustangs, there were plenty of folks turbo-feeding their factory Eaton M112 supercharged Terminator cars and getting huge power numbers (800-900hp). Feeding a supercharger with a turbo is a game changer, best of both worlds scenario, at least in terms of both low and high-end torque. The compound cars pulled so hard off the line whereas the regular turbo cars would lose traction halfway down the track.

 
Confession, for a street vehicle I like having a little lag. One of the joys of a turbo is getting to experience the "before I installed a turbo" and "Whoa, there it is" every time you put your foot in it. :D
 
Is the TRD blower not capable of 10 lbs? Rice, if 10 lbs is all you want, why not just slap on the TRD unit? Set it and forget it. I know it's not as sexy as a turbo but it is reliable, proven and a plug-n-play deal.
 
I like it because it gives you a chance to change your mind :)
 
Is the TRD blower not capable of 10 lbs? Rice, if 10 lbs is all you want, why not just slap on the TRD unit? Set it and forget it. I know it's not as sexy as a turbo but it is reliable, proven and a plug-n-play deal.

While a supercharger can be inter-cooled they came off the shelf non inter-cooled and set up for about 5-6 pounds of boost depending on pulley size. Above that you start heating the charge so much the gains level off. Most important is the TRD units were made for '95+ (OBDII) 80's with a more forgiving engine management system that can compensate the fuel mix up to 7 or 8 pounds and, thus, are bolt on units. If I were driving a 95+ this would be enough boost to keep me happy (Yeah, right). The 93-94 engine management systems are not boost friendly. So if I'm going through the headache of getting an engine management system to work I'm going to want more than 5-6 pounds (i.e. outrun Jason) :flipoff2:
 
Okay. Makes sense. I was not aware that the TRD piece was not intercooled and didn't know about the difference in OBD1 vs. 2 on these trucks. I don't own one you know...at least not yet. Thanks for the lesson!
 
50mm will not supply the volume needed. Not even close. 56mm would be the minimum.

Yeah my 57mm spools way before 3000, I could have full boost by 2200.

In fact I posted some numbers that might make this interesting, let me find them.

Well I didn't find the numbers and this was before my final tune. but you can see we started from 2500rpms and up the turbo was ahead of the stock system. But you can see even with a 57mm turbo it is falling of a little up top.

@2500rpms +10hp +25ft/lbs
@2750rpms +35hp +70ft/lbs
@3000rpms +50hp +140ft/lbs
@3250rpms +95hp + 200ft/lbs
@3500rpms +145hp +245ft/lbs

pre-jpg.950766

To make sure we're on the same page, when you say 57mm, you're talking about the compressor inducer size, correct? We're still talking about the 4.5L 1FZ, right? A 56mm turbo produces plenty of volume for a 5.9L so I don't see how it wouldn't produce enough volume for a 4.5L. EDIT: RPM range, duh.

This 57mm turbo that produces full boost (what is full boost for that application?) what size turbine and turbine housing is it running? The turbine wheel and turbine housing sizes dictate choke points and spool speed much more than compressor dimensions.

Out of curiosity, how much boost would you produce at 2500, 2700, 3000, 3250 and 3500RPMs with the above power numbers?


EDIT2: I'm starting to understand. To get the volume required for a 4.5L engine at 3500+RPM you need a big turbo. This comes at the consequence of having low boost until 2200+RPM or so.
 
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While a supercharger can be inter-cooled they came off the shelf non inter-cooled and set up for about 5-6 pounds of boost depending on pulley size. Above that you start heating the charge so much the gains level off. Most important is the TRD units were made for '95+ (OBDII) 80's with a more forgiving engine management system that can compensate the fuel mix up to 7 or 8 pounds and, thus, are bolt on units. If I were driving a 95+ this would be enough boost to keep me happy (Yeah, right). The 93-94 engine management systems are not boost friendly. So if I'm going through the headache of getting an engine management system to work I'm going to want more than 5-6 pounds (i.e. outrun Jason) :flipoff2:

A deer can/cant outrun Jason these days....or at least partially outrun him, then pull away.

Finish your turbo build and get it situated, and ill swap you for a 97 to build up as a supercharger motor :)
 
Yep you're getting it. On those runs I was about 15-16psi, dropping a little boost after 4250 so I had to swap in a different wastegate can, but it will hold 16psi to redline now.

It is a BW EF7670, .92A/R Twin-scroll housing, Compressor is 57-76mm, Turbine is 70-62mm

To make sure we're on the same page, when you say 57mm, you're talking about the compressor inducer size, correct? We're still talking about the 4.5L 1FZ, right? A 56mm turbo produces plenty of volume for a 5.9L so I don't see how it wouldn't produce enough volume for a 4.5L. EDIT: RPM range, duh.

This 57mm turbo that produces full boost (what is full boost for that application?) what size turbine and turbine housing is it running? The turbine wheel and turbine housing sizes dictate choke points and spool speed much more than compressor dimensions.

Out of curiosity, how much boost would you produce at 2500, 2700, 3000, 3250 and 3500RPMs with the above power numbers?


EDIT2: I'm starting to understand. To get the volume required for a 4.5L engine at 3500+RPM you need a big turbo. This comes at the consequence of having low boost until 2200+RPM or so.
 
That's the other factor then, lower peak boost. Makes sense now. Thanks for humoring me Scott :cheers:

I still think he should aim for at least 25psi :hillbilly:
 
Can't run 25psi on pump gas ;) Max is about 20-21psi maybe 22 if you like pushing it. lol. You have to go E85 or racefuel for anything above that. I know you diesel guys are spoiled. ;) lol

That's the other factor then, lower peak boost. Makes sense now. Thanks for humoring me Scott :cheers:

I still think he should aim for at least 25psi :hillbilly:
 
Can't run 25psi on pump gas ;) Max is about 20-21psi maybe 22 if you like pushing it. lol. You have to go E85 or racefuel for anything above that. I know you diesel guys are spoiled. ;) lol

I'm a bit conservative. In my case, having not dished the pistons and both head and block being decked (the bare minimum but not zero) it will be safer at say 16-17-ish in the absence of other helpers such as water/meth. There are some E-85 (and race fuel) vendors in the area. While I would consider race fuel for reduced-hazard tuning I sure don't wish to make it mandatory.

The diesel guys really do have it made. Between the narrow RPM band and timed injection there really is no better setup for a turbo.

Time for a bigger turbo Johnny. :flipoff2:
 
Aside from sheets I don't see a lot of ethanol vendors around. That said it seems to be enough to consider it. Boost controller can be tied to an ethanol sensor, so when ethanol isn't around it turns down the boost. You can safely mix both and it'll figure out where to put the boost to optimize power.

Those are all words said to be by the same two people that failed to wire up an ECU, so take them with a grain of salt.
 
Saw Steve at the meeting tonight and he hinted the thread might need a bump. Sorry to say I have no news. There are a few items on order such as plugs, wires, rotor, cap, and fuel filter but otherwise am in a holding pattern until I can get through another 6 days of teaching.

We're still on go for engine swap on Jan 7th sans any unforeseen issues.

I will be heading back to Asheville on Jan 20th to see Ben for our now-annual birthday lunch and hope to be able to take the 80 for him to see his Jap motor in action, pre turbo of course.
 
Pre-turbo is where you put an egt probe .... just sayin'. :hillbilly:
 

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