Comparative 1UZ Piston Weight

The 1UZFE EGR Delete Kit is available for sale here.
I am contemplating using the Ross forged piston on the (early) standard 1UZ con rod in a low boost (10 psi) Vortech supercharged configuration but am concerned that these pistons weigh more than the standard 1UZ piston. My concern is that the additional weight will cause additional stress on the con rod. Is the forged piston, in fact, heavier? I have searched for this data on this site, and elsewhere, without result.

Your input would be appreciated.

Dr. Jeff Harper
Harper Racing
Bangkok, Thailand

http://drjeffbangkok.squarespace.com
 
After reading the 'forced induction' thread, it looks like I might just get away with using the standard pistons anyway - on an unopened 1UZ - with the addition of Kelford 264 cams and larger injectors (550? or 315?). I have a MicroTech LT12S they will reprogram for me to use in batch fire mode (ignition and injectors). I would like 400-450rwhp.

By the way, it seems to me that if I am firing my injectors in pairs (one 'dead, one timed live), I do not need to go with such large injectors because they will be firing twice per intake event anyway. True?

Your help will be appreciated.

Dr. Jeff Harper
Harper Racing
Bangkok Thailand

http://drjeffbangkok.squarespace.com
 
Hi there Jeff, I don't know how we all missed your earlier posts, but sorry to see you had no replies; you have a really interesting project there.

I've got a set of forged Ross's still in the box, and some OEM 1UZ pistons, and will weigh them both for you when I get home in two weeks, if you're still interested.

Understand you'll be running an AEM? A couple of us have this setup currently, so if you need maps, etc. let us know. I run COP's and I think another member has his running on the stock dizzies.

We also have a resident AEM guru here - Mitch Peterson, who was formerly one of AEM's design/development/support engineers, and he's probably forgotten more about that ECU than most of us will ever know.
 
Cribbj,

Thanks for your reply. I am interested in the forged pistons, was thinking about perhaps putting them on the standard con rods, but didn't want to put anything there that was heavier than standard.

My project is progressing nicely. I have gathered up almost all the pieces I will need. I will remove the 1.5JZ from the race car in about a week and begin the fitment of the 1UZ. My measurements show an oil filter-to frame interferenece and perhaps a steering column issue . . . . we'll see. I will use the same rear trans mount,which will define the engine location (and not necessitate a new prop shaft). A Mazda Familia is a VERY small vehicle . . . . but the 1UZ is actually lighter than my 1.5JZ . . . . so some free artificial horsepower for me!

Yes, I may be in the need for some input on the AEM tuning down the road. I already have a map for a similar supercharged 1UZ for start-up purposes . . . but who knows what this particular motor will want in the way of a map.

More to come.

Dr. Jeff Harper
Harper Racing Bangkok
 
Hi there Jeff, I don't know how we all missed your earlier posts, but sorry to see you had no replies; you have a really interesting project there.

I've got a set of forged Ross's still in the box, and some OEM 1UZ pistons, and will weigh them both for you when I get home in two weeks, if you're still interested.

Understand you'll be running an AEM? A couple of us have this setup currently, so if you need maps, etc. let us know. I run COP's and I think another member has his running on the stock dizzies.

We also have a resident AEM guru here - Mitch Peterson, who was formerly one of AEM's design/development/support engineers, and he's probably forgotten more about that ECU than most of us will ever know.

He's running http://www.microtechefi.com/microtech-products.php?product_id=5
 
XR8tt, thanks for your interest. I have changed my mind about upgrading the MicroTech ECU I am currently using on my 1.5JZ for use on the 1UZ (as I mentioned here and on the Microtdech forum). The guy who is buying my 1.5JZ is also buying the MicroTech, loom, coils, and wires. I will be using the AEM unit with four (4) MSD GM-style DIS coils in the wasted spark configuration. The MicroTech was an excellent unit, and I have no complaints: it did what it was suppose to do very reliably. However, I can do so much more with the AEM . . . and I plan to. I am maintaining a "Racing Projects Blog" on my web site with updates and progress.

Regards,

Dr. Jeff Harper
Harper Racing Bangkok
 
XR8tt, thanks for your interest. I have changed my mind about upgrading the MicroTech ECU I am currently using on my 1.5JZ for use on the 1UZ (as I mentioned here and on the Microtdech forum). The guy who is buying my 1.5JZ is also buying the MicroTech, loom, coils, and wires. I will be using the AEM unit with four (4) MSD GM-style DIS coils in the wasted spark configuration. The MicroTech was an excellent unit, and I have no complaints: it did what it was suppose to do very reliably. However, I can do so much more with the AEM . . . and I plan to. I am maintaining a "Racing Projects Blog" on my web site with updates and progress.

Regards,

Dr. Jeff Harper
Harper Racing Bangkok
Na Jeff I was responding to to your second post on here..
As I have found out in the past..
It doesn't matter what ECU you have..
Most the time, if the tuner is NOT FAMILIAR with it !!
Then the tune won't be 100% perfect..
One thing the Microtech tends to do is dump fuel at higher boost levels..
Which works well on rotories, "drag only" tunes etc..
Down under we tend to use Motec or Haltech being Australian brands and local with HEAPS of back up.. Which I cannot say the same for Autronic unfortunatly!!! But I digress...
 
if i can be assed finding some digital scales that will cover the weights required... ive got a suite of pistons here i can weigh for you if still interested?

cheers
ed
 
I don't think 10 psi of boost can get you anywhere near 400 rwhp even with a good tune. You'll need at least 13-14 psi to be there. I'm running 13-14 psi with a turbo system and my tuner could only get it 334 rwhp & 378 rwtq. My setup is with low compression so I don't expect the rwhp can go as high as an OEM compression. And 550 cc/min fuel injectors might be the ticket. The 315 cc/min injectors are too small for that power.
 
Mine made 489WHP at 16psi.

n640914967_2128456_1009.jpg
 
Plus Jeff's going to lose 20-50 shaft HP driving his SC, where the turbos don't have that problem.

Their problem is just a bit of constipation on the exhaust side ;-)
 
I don't think 10 psi of boost can get you anywhere near 400 rwhp even with a good tune. You'll need at least 13-14 psi to be there. I'm running 13-14 psi with a turbo system and my tuner could only get it 334 rwhp & 378 rwtq. My setup is with low compression so I don't expect the rwhp can go as high as an OEM compression. And 550 cc/min fuel injectors might be the ticket. The 315 cc/min injectors are too small for that power.

ORLY ;) maybe not with an SC but my latest tune netted 333rwkw on ONLY 10psi :)...that's well over 400rwhp Steve :nana:
 
If you're here, I'd buy you a pack a beer and then will take you to see my tuner. :06:
Your turbo will only support so much hp Steve...boost isn't boost so to speak so my 10psi with medium sized twins is moving alot more air than your single T 10psi...that said, i think a more agressive ign adva and using some decent fuel would net you and easy 50hp gain. from memory yout AFRs are OK but maybe a bit more lean would also help. No idea what you exahust flow is like either and this area is about the easiest place to make hp with a turbo is you have the room to play with.

Enough thread hijack, pm me if you want to chat options.
 
piston weight

I have a set of ross forged pistons 8.5 compression and the paper work states 363 grams.

cheers, Al.
 
Thanks for the replies . . . and the helpful information on piston weight. Yes, the auto trans sucks some power, but for drag racing on a sometime slippery track, it is the way to go. Do not underestimate the power loss of turbocharging as a result of exhaust restriction - it can be substantial. I will be using open, stepped headers with merge collectors and nothing else.

I am interested in knowing whether these estimates for RWHP, and reported RWHP by boost were on engines with race or standard camshafts. Also, I will be running higher compression . . . around 9.25 with my SC. I would be happy with 375 RWHP in my light car for my brackets. I know it is very difficult to get accurate dyno numbers with a high stall converter as well. But I did run a 10.87et on an earlier 1JZ that had produced 402RWHP at 1.3 bar (shifting at 5500, launching at 2500 on a slippery track). I ran a 10.63et at only 0.9 bar (12 pounds) with my 1.5JZ, although it had never been on a dyno.

I am now settling on the readily available 430cc(??) "yellow top" injectors as being good enough, although I am looking for some used 550s without luck here in Bangkok.

Here's a pic of the motor so far with the the deep sump oil pan, heads, and camshafts installed. What a nice lump of aluminum this is!

Regards

HarperRacingBangkok
 


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