Hybrid stroker project
06-10-2012, 01:23 PM
#211
Race Car
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Location: TEXAS
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Bruce, both Sid and I know that you are being genuine with your opinion, but the context is wrong. This is Sid's thread about his unique stroker engine, showing its merits. By arguing that altitude has no effect, your are (intentionally or not) diminishing the results of his achievement. Sid has run, IIRC, 116mph at 12psi of boost with this engine. To hit 110mph, I had to significantly more boost (and more aggressive timing). I highly doubt anyone would suggest that my car is poorly tuned.
The end result is that Sid's 2.9L motor, even with a very conservative tune, is leaps and bounds more powerful than my 2.5L. (and his has more potential)
The end result is that Sid's 2.9L motor, even with a very conservative tune, is leaps and bounds more powerful than my 2.5L. (and his has more potential)
Post up your math, and I'll show you where it falls short or is wrong. Not meaning to offend, but the old adage, "A man with experience is never at the mercy of a man with an opinion" holds true here. Furthermore, I've posted a relatively significant amount of math & points on this subject in the past, to include this thread to no effect... It seems that my effort does no good, as some just ignore any factual evidence I've posted.
Also, I'm not sure where you are pulling 27.5% from...? 12psi in Bandimere is 12psi + ~10.7psi of atmosphere, for 22.7psi total pressure; 8psi at sea-level is 8psi + 14.7psi of atmosphere, for 22.7psi total pressure. Sid's point holds, as 22.7psi total is the same in both locations.
Also, I'm not sure where you are pulling 27.5% from...? 12psi in Bandimere is 12psi + ~10.7psi of atmosphere, for 22.7psi total pressure; 8psi at sea-level is 8psi + 14.7psi of atmosphere, for 22.7psi total pressure. Sid's point holds, as 22.7psi total is the same in both locations.
Last edited by 95ONE; 06-10-2012 at 03:23 PM.
06-10-2012, 03:10 PM
#212
Three Wheelin'
Join Date: Jan 2002
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06-10-2012, 03:53 PM
#213
Race Car
Thread Starter
Bruce, don't stress over it. I got a bit emotional. My bad really.
However, I'm at the track again today, right now watching cars go slow. A GTR with a good driver is running 11.8@ 117. These cars are stock ten second cars at good air. They even have all the bells and whistles to make sure pressure is equalized.
Run after run today I'm watching cars that should be running much faster times go slow.
It's a tuner race so most cars here are turbo setups.
I know you're trying to prove a point with mathematics and what turbo companies are saying, etc..... It just doesn't work that way.
If you'd like I can video car after car running slow as hell.
I truly respect your opinion. I just completely disagree based on what I'm seeing.
The reality is.... I'm busting my *** to run 115 when I see many 951's run out higher mph with minimal mods. I see the same modded type setups up here just going over 100.
I'm not educated enough to explain why this is it just is.
I had thought of a funny cartoon running through my head where.... I'll just play it out in words....
Set the scene,......
I'm driving, josh is in the passenger seat. You and pat are in the back....
We are repeatedly driving up 10,000 ft man passes....(less than the difference we are talking about)
I'm trying like hell to keep up with GTR's,Evo's, etc. they are not passing me by much....
I'm stressing bc I'm having to push the crap out of my car, I'm watching every gauge like a hawk, temp rises, I'm having to keep turning up the boost etc.
Josh is working his *** off trying to tune it to perfection..
It's pretty stressful.....
Finally we have it pretty well dialed to where things are not quite as stressful .....
You speak up and say, "you know there's not much difference between this and sea level", "I hear the turbo companies state that turbine PR is real advantage", " I also hear that these passes are downhill to make it easier to run"......meanwhile the car is working very hard to keep up and we are getting closer to that GTR that's just inching past us...struggling to pull us....
Pat chimes in with "I hear that higher altitude has cooler air".......meanwhile I'm roasting my *** off in 95degees and the sun is so much more potent without as much atmosphere protecting us.
Josh and I look at each other, look back you guys and just throw up our hands and say.... "Damn it's so easy pulling these mountain passes we should all race at 10000 ft.."
Meanwhile, we are passing broken cars left and right on the side of the road.
Then we just bang our heads on the dashboard repeatedly.
It's funny in my head but you need little cartoon characters to visualize.
Xtranormal anyone??
However, I'm at the track again today, right now watching cars go slow. A GTR with a good driver is running 11.8@ 117. These cars are stock ten second cars at good air. They even have all the bells and whistles to make sure pressure is equalized.
Run after run today I'm watching cars that should be running much faster times go slow.
It's a tuner race so most cars here are turbo setups.
I know you're trying to prove a point with mathematics and what turbo companies are saying, etc..... It just doesn't work that way.
If you'd like I can video car after car running slow as hell.
I truly respect your opinion. I just completely disagree based on what I'm seeing.
The reality is.... I'm busting my *** to run 115 when I see many 951's run out higher mph with minimal mods. I see the same modded type setups up here just going over 100.
I'm not educated enough to explain why this is it just is.
I had thought of a funny cartoon running through my head where.... I'll just play it out in words....
Set the scene,......
I'm driving, josh is in the passenger seat. You and pat are in the back....
We are repeatedly driving up 10,000 ft man passes....(less than the difference we are talking about)
I'm trying like hell to keep up with GTR's,Evo's, etc. they are not passing me by much....
I'm stressing bc I'm having to push the crap out of my car, I'm watching every gauge like a hawk, temp rises, I'm having to keep turning up the boost etc.
Josh is working his *** off trying to tune it to perfection..
It's pretty stressful.....
Finally we have it pretty well dialed to where things are not quite as stressful .....
You speak up and say, "you know there's not much difference between this and sea level", "I hear the turbo companies state that turbine PR is real advantage", " I also hear that these passes are downhill to make it easier to run"......meanwhile the car is working very hard to keep up and we are getting closer to that GTR that's just inching past us...struggling to pull us....
Pat chimes in with "I hear that higher altitude has cooler air".......meanwhile I'm roasting my *** off in 95degees and the sun is so much more potent without as much atmosphere protecting us.
Josh and I look at each other, look back you guys and just throw up our hands and say.... "Damn it's so easy pulling these mountain passes we should all race at 10000 ft.."
Meanwhile, we are passing broken cars left and right on the side of the road.
Then we just bang our heads on the dashboard repeatedly.
It's funny in my head but you need little cartoon characters to visualize.
Xtranormal anyone??
06-10-2012, 04:15 PM
#214
Race Car
Thread Starter
Dana, I have over 20 nozzles, and probably 150 jets. I've thought about it but , IMO it just isn't fair. Plus I like not having to spend $$ refilling repeatedly.
06-10-2012, 07:12 PM
#215
Rennlist Member
Just to clarify if there was any doubt, I love reading about the guys who are pushing these cars and doff my cap at the lot of you. Keep it coming.
06-10-2012, 08:38 PM
#216
Race Car
Thread Starter
Went again today. Yes I'm just having a blast racing this thing
I was actually a bracket racer today (where you make your time runs and try to run as consistent as possible against others in eliminations)
I actually made through 3 rounds before "red lighting" (leaving too early). Sucks that I did that because I ran right on my dial in . I had been dialing in 12.56 all day and I decided to dial 12.86 so I could "fender race". Well it worked well as I ran perfectly on my time but I had left too early by .041 seconds
. The car was a bracket machine.
I had changed the cam (lost my low end tq, but that made it easy to launch, felt like the 2.5). I don't like it so I'll swap it back most likely, or do another grind. I went too big and it sounds really cool but, it's shifter the power band too far to the right, I advanced it a bunch, but it still doesn't seem like what I want. So that'll be gone soon. I am thinking about trying it Wednesday because it was very hot today. We'll see.
I didn't have time to put on my drag radials in Friday so I ran my regular tires. Again though, it was easier to launch and I was getting 2.09 60' times vs the garbage before.
It does kind of suck to be doing these things and not seeing gains, but I do need to make sure the parts are working. So far the engine has been a great platform for trying new things.
I'm not sure I'll change tires or go back up again with these to do a direct comparison. (I really need another set of wheels)....
Anyway....that's all folks
I was actually a bracket racer today (where you make your time runs and try to run as consistent as possible against others in eliminations)
I actually made through 3 rounds before "red lighting" (leaving too early). Sucks that I did that because I ran right on my dial in . I had been dialing in 12.56 all day and I decided to dial 12.86 so I could "fender race". Well it worked well as I ran perfectly on my time but I had left too early by .041 seconds
. The car was a bracket machine.I had changed the cam (lost my low end tq, but that made it easy to launch, felt like the 2.5). I don't like it so I'll swap it back most likely, or do another grind. I went too big and it sounds really cool but, it's shifter the power band too far to the right, I advanced it a bunch, but it still doesn't seem like what I want. So that'll be gone soon. I am thinking about trying it Wednesday because it was very hot today. We'll see.
I didn't have time to put on my drag radials in Friday so I ran my regular tires. Again though, it was easier to launch and I was getting 2.09 60' times vs the garbage before.
It does kind of suck to be doing these things and not seeing gains, but I do need to make sure the parts are working. So far the engine has been a great platform for trying new things.
I'm not sure I'll change tires or go back up again with these to do a direct comparison. (I really need another set of wheels)....
Anyway....that's all folks
06-10-2012, 08:53 PM
#217
Rennlist Member
Shawn I didn't take any photos of it. The un-shrouding I did was around the intake outside edge of the combustion chamber. If you look at the factory head you'll see that the seat and chamber have to make a turn back towards the cylinder. I opened that area up and polished it out a little. If you go through with the larger valves you'll certainly need to do this. You can use the head gasket and dowels to make your mark. Remember though you'll be using the 103mm cometic and you don't want to go quite all the way out to that point. Just inside it. You'll see what I mean once you match up the gasket to the head and then to the block.
You can also clean up the exhaust a little as well and definitely take a look at the seat to liner matching, I have seen most be off by .063 very often.
You can also clean up the exhaust a little as well and definitely take a look at the seat to liner matching, I have seen most be off by .063 very often.
What did you use to cleanup the exhaust liner? Some kind of diamond bit? Also, when un-shrouding the intake did you open up the chamber perpendicular or did you angle the chamber wall towards the cylinder wall?
06-10-2012, 09:04 PM
#218
Race Car
Thread Starter
I went pretty much perpendicular. There isn't much room to angle it outward.
06-10-2012, 09:09 PM
#219
Rennlist Member
06-10-2012, 10:11 PM
#221
Rennlist Member
Sid, did you swap from a stock cam to a high lift one? Do you want to say what specs these cams are or keep this quiet for now. What weight is your car now?
06-10-2012, 10:48 PM
#223
Race Car
Thread Starter
Patrick, I'm pretty open so I'll share.
The cam I had done is 244 degrees on the intake lobe @ .050 and 240 in the exhaust with 290 and 288 full duration. The lift is close to factory. This was my first attempt and I was trying to make it so they could be available to the masses for cheap without having to use lash caps. The profiles were also on file is it was easier. I wasn't able to pull that off and in hindsight I could have chosen most any grind I wanted due to having to remove a little material off the base. Now that I know the lash caps work and the lifter gets plenty of oil still (main concern) I can adjust. I just went way too big and it didn't work out. At least for DDing.
The car pulls ok on the top end but low end sucks. It sounds cool thoug.
I'm going to do a bit more research before I design the next one (first turbo attempt).
The good news is, the lash caps work perfectly.
The cam I had done is 244 degrees on the intake lobe @ .050 and 240 in the exhaust with 290 and 288 full duration. The lift is close to factory. This was my first attempt and I was trying to make it so they could be available to the masses for cheap without having to use lash caps. The profiles were also on file is it was easier. I wasn't able to pull that off and in hindsight I could have chosen most any grind I wanted due to having to remove a little material off the base. Now that I know the lash caps work and the lifter gets plenty of oil still (main concern) I can adjust. I just went way too big and it didn't work out. At least for DDing.
The car pulls ok on the top end but low end sucks. It sounds cool thoug.
I'm going to do a bit more research before I design the next one (first turbo attempt).
The good news is, the lash caps work perfectly.
06-12-2012, 07:42 PM
#225
Rennlist Member