compression ratio

[chiplee]

I went ahead and bumped lizzord's sheet over in the B/S forum so we could get to all of them easily.  I know his set up was very different from mine and mikes but he too never made any real HP and shows fade away at 4500 rpm.  There are plenty of things in his set up that we could attribute his drop off to, but the fact is that in mine and Mike's setup, where the problems you would blame Lizzord's curve on have been fixed, you see the same drop.  Almost as though it's not the cam or the turbo.  Lizz: you were figuring your turbo ran out of puff and your cam was too small right.  Perhaps.  Notice how the smaller the cam is in each run the sooner we're making torque, makes sense but does it mean the cam needs to be even bigger to move the curve farther right and get big HP.  

     

[Boosted_One]

wow, that dyno run of Chips is very similar.

 

This is what I am saying, it isn't the tuning aspect as a whole.  Nothing I could have done whether on the TBI or on the MPI at the times of the dynoing would change that drop off.

 

There are areas that I, or we, need to address.

 

I have seen quite a few runs from CNM and a lot of the runs show a similar drop off.

 

This is why I continually say it isn't tuning!!

[kev]

Perhaps these damn internals are just too heavy!   Heavy crank, heavy rods, long stroke, etc.   Doesn't Bill TSG run custom rods?  That may be the reason for the higher revs.   Andy's, Chip's, Mike's, Lizzord's, etc. runs share the same pattern.  Well so do Bill's but his pulls to a little bit higher rpms.    Maybe the way to higher hp would be to destroke the engine?  

 

All of this data is basically making me conclude that this is about as much as we are going to get out of the stock 2.6 bottom end.   The cams seem to be doing very little for overall horsepower.   We upped the flow tremendously which produced higher numbers but still wouldn't let the engine rev.  Only thing left is the bottom end!

 

kev

[Conquest]

kev,

 

That is a great thought. That makes perfect sense. In my opinion, I would rather not destroke the engine, and would liek to keep the crank due to it being tough and nitride hardened, but getting tough but super light on the flywheel, connecting rods, and pistons will help alot, I think. Of course, in addition, to what was previously done to up the revs.

[importwarrior]

can heavy duty Small Block Chevy  valve springs be used on our cars?

[Joel]

Bill's rods are perhaps custom, but they don't destroke it from what I can tell... it's still a "2.6". I wouldn't imagine custom billet rods being a performance modification, more of a safety modification. The weight loss wouldn't add HP. It can't. It would make the motor accelorate faster with the same power. Thats like saying a flywheel makes HP. It doesn't, and its worth nothing on a dyno pull. It's worth something in real life acceloration.

 

Which is also another thing. Dyno's are not the end all to performance. They are just notable graphs to give ideas.

 

What I would really like to see is some dyno pulls from Tim C, I wanna know what his Cams are doing and if they are helping. I don't think the butt dyno is doing justice for anyone at this point.

 

Lizzord also needs to take his T3/T4 to the dyno. I wanna see that turbo is doing.

 

Joel

[Boosted_One]

I went ahead and bumped lizzord's sheet over in the B/S forum so we could get to all of them easily.  I know his set up was very different from mine and mikes but he too never made any real HP and shows fade away at 4500 rpm.  There are plenty of things in his set up that we could attribute his drop off to, but the fact is that in mine and Mike's setup, where the problems you would blame Lizzord's curve on have been fixed, you see the same drop.  Almost as though it's not the cam or the turbo.  Lizz: you were figuring your turbo ran out of puff and your cam was too small right.  Perhaps.  Notice how the smaller the cam is in each run the sooner we're making torque, makes sense but does it mean the cam needs to be even bigger to move the curve farther right and get big HP.  

     

 

One small thing I have noted is on Lizzords, Bill and my run our torque pulls were all near each other. I think bill pulled like 349 ft/lb Lizzord pulls 339 ft/lbs and I pull 339 ft/lbs.

 

Are the limits of the TDO5 exhaust housing showing? It just seems too similar to discount. Even though our HP ranges varied widely this torque similarity  carried thru.

 

These 3 people are the only dyno pulls I have seen over the 300 ft/lb range. So it's all I'm going off of.

[kev]

Bill's rods are perhaps custom, but they don't destroke it from what I can tell... it's still a "2.6". I wouldn't imagine custom billet rods being a performance modification, more of a safety modification. The weight loss wouldn't add HP. It can't. It would make the motor accelorate faster with the same power. Thats like saying a flywheel makes HP. It doesn't, and its worth nothing on a dyno pull. It's worth something in real life acceloration.

 

Which is also another thing. Dyno's are not the end all to performance. They are just notable graphs to give ideas.

 

What I would really like to see is some dyno pulls from Tim C, I wanna know what his Cams are doing and if they are helping. I don't think the butt dyno is doing justice for anyone at this point.

 

Lizzord also needs to take his T3/T4 to the dyno. I wanna see that turbo is doing.

 

Joel

 

I do see what you are saying but on the upstroke a heavier rod will come into play in reducing the rpm potential of the motor (there is gravity there).  Also I believe that any weight reduced on the rotating assembly of the engine will increase rpms thus increase horsepower potential.  I actually do feel that lightening the flywheel increases horsepower (well at least horsepower potential, you need other things to take advantage of that slightly higher achievable rpm to generate the hp).  It enables us to rev faster and farther due to the less mass.  Now it only does it on the original full blown acceleration, it probably robs horsepower if you let off and then kick it again because the revs will drop faster and then have to restart.  

 

Anyways, I really do feel that this is the case here.  Every dyno run has the similar drop off slope and response.   A destroked engine is the key to bring out the higher rpm numbers.  However will we sacrifice the excellent ramp up to peak horsepower if we do it?    This is just like the big block vs. small block V8 situation.  The big block has massive torque and a achieves high hp numbers very early in rpm range and falls off where as the small block takes a bit longer to hit its mark but the high rpms that it can hit are a huge benefit.  

 

I myself am happy with what I have (stock internals that have been lightened slightly).   I will be happy to get the numbers Mike has and also play around with other things like turbo housings, cams, etc. to push that rpm dropoff a little bit further out there.   Plus I already spend $3000 on machining this block, hehe.  

 

Ok tell us your secret turbo Mike, hehe.  I actually have been greatly considering a T04B like Chad is running.  It has very impressive flow ratings with a much larger exhaust housing.   A bit more lag down below though.

 

kev

[Boosted_One]

It will be a t04b HI-FI 60A/R  1.15 turbine wheel P-Trim Tang divided turbine housing

 

http://64.225.76.178/catalog/images/t4.jpg

 

 

We'll just see how this puppy does. I'd say the TO4B has a little on the 20G I'll still get this thing online early.

 

I do like my torque but I need a few more ponies.

 

I think a destroke would help, BUT I think we would need less than say 2.5 or 2.4L.

 

Maybe we need to get the TDO5 exhaust housing out of the picture to see if it is a culprit on a dyno run.

[dstar26t]

Please say you'll spend the extra cash and get a ceramic/ball bearing one???

 

Nate

[chiplee]

what do they not hold up or something, you're not just talking a little extra cash there.

[Shelby]

befor we go throwing out the  turbo houseing  or  blameing any one thing  for the drop off, maybe we should ask  where is the  cam timeing actualy at, i for one  have been listening to the  guys sett he cam and  chains in for yr's with one saying   mine's a hair befor the 12;00 and a couple others say well mine is  just a bit  past 12:00, well we all know this  will work for a stock motor  running  7 to 10 lbs of  boost, but  we talking a  diff ball game,  has any one   taken the time to degree a stock  cam  and  gear set up, and  where was it at ,   i know  the finding's on any one car means  nothing as  each and every one of our  engine's  will be  a lot diff, just how  close is the standards for the after market gear sets,  i have  on gm cars found  as much as a 24 degree  late  cam  with all new   gears and chains , so  so much for the  advanceing  so it  can wear in theroy , and  degreeing the cam  in was  one of the  best tricks  to  pulling a lot of unuse's horses out of  a big block mopar

 

maybe the exhaust is  the  hold up and the turbo houseing isn't flowing enought , or the cam isn't big enought,  292  on a  small block v8  certainly isn't any  big  cam at all , but the turbo change all that a bunch,  but the  fact we are useing a turbo makes the cam timeing  all that much more cridical

and  with all the work and  effort to get these cars set up  right  , that  seems to be the one place  we're missing the  boat   doing mainly because of the lack of  suport finding  a way to change it  even if it is way out of  spec's. and lets  face it  a 6 degree change isn't gona  help  if your 20+ out  of  spec  opening time to start with, i'm just  saying  this is some thing  we need to explore  befor going  on  and saying for sure the  turbo is at  fault,  after all this drop off is right  where the factory  set the  max out put  for this cam(stock)

as i've found state'd on  several sites  about cam and turbo  engines the  valve over lap and  top end  timeing has a  huge effect on the max  horse power and the  rpm  range it's made at  more so then the  actual lift  and duration of the cam

i  know  back when the  240 , 260 and 280Z's were arround  i  always went  with  the +7 timeing  mark as it raise'd the  upper end  power band   by a good 500 rpm's  sure it   drop'd the low end  power a bit  but   they guys were looking for top end and  never notice'd , not once did they   ever  say a word  , but they sure  did coment  about the upper  end  increase

 

maybe if enought of us  get togather we can get some one to  make an adj cam gear for us , they sure don't mind    takeing out money for the other stuff they sell, but untill now we never had reason to have to have it  , thanks to the mpi intake  

but befor  we  can   look for a gear we  need to know  what  kind of  adj  range we  may need , i'm  putting a stock engine togather now and i'm going to  check the cam  timeing on it as i put it togather   just so i  know where it's at , wheather i can correct it or not

[Boosted_One]

Got a good deal on it. No cermaic ball bearing.

 

I'd like to but things are adding up already. Another build and all.

[Lizzord30]

Hey thats the same compressor side i have Its a nice sized turbo Altho i have a T3 turbine at lest its a lot larger then TD05.

[Tim_C.]

I should go down & do a dyno run with my FP cranked to 70 whre it needs to be to support 10PSI Boost. I would hope for somewhere around 250-275HP Flywheel. But I really think the RPM band would go to 5800+. It's just too crazy for revving.

Except it's all wasted on a stock TB! I've got a gazillion other mods, but if I can't crank up the boost(to 18 MAX), then none of them are paying off. I just need to be patient and get the fuel, with a larger TB opening. That means MPI, but I want to go the limit with the stock TB just because I'm so close. Maybe I can sell a good proven unit after just putting a little in it? The car is flat out scarey, & I know I aint close to the MPI guys.

I want to try the adjustable cam gear. Figuring out how to dial it in would be my challenge. That's where Chip's books are valuable, so I can get a good place to start.

We are all saying, this guy has this, that guy that, but really, there are many differences in our individual set-ups that are making for an apples to oranges comparison it seems like?

Heef has the 7:1 CR, but the best intake on the market?

I agree that hardware is a big issue. The right combination of parts is most important. Take my cam for instance; it's way too big. When I ordered it, I didn't know the rockers were 1.5 ratio, or that the roller version of the 284 had a 476 overall lift w/1.4 rocker figure?

That turbo is too awesome! Just looking at it give me goose pimples!  I think it will be the ultimate turbo rush when spooling that baby!

Oh, BTW: Destroking down to a 2.4 shouldn't be that hard. Any crank grinder worth his salt can destroke. Just start with a virgin crank, and do what Tony Waldrop did, except the other way. It may be the equivalent of going .030 under or so, but it can be done & still be a good Hi-RPM crank.

 

Tim C.

[dstar26t]

Got a good deal on it. No cermaic ball bearing.

 

I'd like to but things are adding up already. Another build and all.

 

I guess if the turbo is built already then you have no choice. But, in my experience, a few friends have bought T3/T4's and they all say they wish they had saved a little more money and got the ceramic/ball bearing upgrade.  That's with hybrids, not the monster you're attracted to.  With the ceramic/bb upgrade, the powerband would be a bit fatter since it spools up faster and since we can't wind out our motors, my preferance would be to get that torque started ASAP.  Now, I haven't witnessed the difference my self but I imagine it's considerable.  What kind of lag are you expecting from that big sucker?

Nate

[heefner]

Well it didn't work yet. I will put the pics in when I get them up. Guess you will just have to wait.

 

Well, I finally have my dyno runs scanned but not sure if I can post them. :

I have 2 runs, not sure what the boost was set at but I'm thinking it was 24psi. These were tunning runs right after I had the engine built and I was not present when they were done.  I'm assuming they were done on 93 ocatane pump gas as I was not notified and it was not specified anywhere. Hopefully this winter I will have a few more quality runs after I change t-bodys. I'm taking it to Bill's shop to do some real tunning.  Sorry for poor quality scans. Hope this helps

 

 

this one is 298.6 whp and 336 tq. max.  

 

http://images.snapfish.com/33578%3C6323232...%3B4%3A95ot1lsi

 

 

this is 285whp and 318 tq of tourque its not the last run but it was the last one I have.  

http://images.snapfish.com/33578%3C6323232...%3B4%3A96ot1lsi

 

Both pics show power past the 4.5k rev range. I'm not sure the specs on the cam but according to Bill there are only 2 companies, Baker and Schnider, that make cams for our car.  I think its the baker 292 ??? EIP sold it as the street strip cam. Solid lifter head with dual springs.  EIP flowed the head also. I run the 20G 1A same as Chip with no porting on the turbo or manifold that I know of. I have a large spearco custom I/C and (2.25 turbo side and 2.5 intake side) hard pipes. I'm running a stock mustang t-body (65mm?), 3" exhaust with NO cat. and a flowmaster muffler.  New stock mitsu crank,  shot-peend and cryoed rods with a copper head gasket.

[Boosted_One]

Your runs are falling off similar to mine are, just dropping later. If you look 4600 it really drops. One thing too it notes the pulls are in 3rd gear. All my pulls were in 4th at the 1:1 ratio. Not sure to what extent that'll change things.

 

One thing I do see as common is the torque number again. Heffner is at 336 puts him right in the same boat as Bill, Lizzord and I.

 

So the cam is a 292 duration?

 

That could explain part of my 258hp to your 298 hp but my torque is at 339 vs your 336. You'd think the torque numbers would be higher on a higher HP run ??

 

Glenn has a few cams over there in AU that are available. One company makes 6 different grinds for the 2.6.

 

I think we are seeing the power curves on our motors guys...

[Conquest]

So...you think this is our engine's power curve?

 

What does dyno show for EIP Tuning's cars? Are they the same power curve?

[Boosted_One]

I guess if the turbo is built already then you have no choice. But, in my experience, a few friends have bought T3/T4's and they all say they wish they had saved a little more money and got the ceramic/ball bearing upgrade.  That's with hybrids, not the monster you're attracted to.  With the ceramic/bb upgrade, the powerband would be a bit fatter since it spools up faster and since we can't wind out our motors, my preferance would be to get that torque started ASAP.  Now, I haven't witnessed the difference my self but I imagine it's considerable.  What kind of lag are you expecting from that big sucker?

Nate

 

I don't have the turbo in my hands. I just bought it and it's coming.

 

An equal length custom header and external WG are going with it.

 

It'll lag a little. But the damn thing will throw my tail back in the seat, and I love that!

 

The exhaust housing is going to flow like the Nile compared to my TDO5, which does alright but not as well as the T4 housing will do.

[heefner]

Mike that drop at 4600 is a boost spike or something, if you look closely, one dyno sheet is numbered 070 (the one with the spike) and the other is 081. I think that spike was tunned out.  So my current hp curve is simillar to the one of lesser hp. This is one reason I have issues with EIP.  They are so secreative with their stuff like the cam.  Part of it was my fault for not asking.  For me to go back now and ask seems like more of a pain than its worth.  I really don't like dealing with them.   As for gearing, I always thought 3rd was 1:1.

[kev]

Nope 4th is 1:1

 

kev

[Boosted_One]

http://www.well.com/~mosk/Images/dyno1.jpg

THIS IS NOT A G54B DYNO RUN

 

 

See how nice the HP stays?

 

Never mind the numbers, the characterisitics of the curve is what I am saying.

 

This is a Toyota motor 22r (?) I believe, the page is http://www.well.com/~mosk/workinprogress.htm

 

Different motor I know but the HP curve stays up nicely.

[kev]

Notice that he burnt up a piston with the 8.5:1 CR JE's!!   He dropped down to 8.1:1.  I don't see any mention of what turbo that thing is though?

 

kev

[Boosted_One]

T3/T04E ball bearing turbo with a 50 trim compressor and a Stage II, .48 A/R turbine wheel.

 

Enough to blow a piston I guess.  :-/