FEOA Forums banner
1 - 20 of 40 Posts

·
Registered
Joined
·
378 Posts
Discussion Starter · #1 ·
Cam, pistons, head work and a ECU tweak. I think there is another 5-10 Hp left in the tune but I am sticking to a 12.5:1 AFR at WOT to keep it safe.

This is at the wheels .... I'm guessing there is about a 15% loss from the flywheel making the Hp about 135. My target was 140 so I got close.

 

·
Registered
Joined
·
378 Posts
Discussion Starter · #6 ·
Not discouraging at all. The problem is that most folks BS about performance and especially about performance gains with their products. Like the 15Hp gain from a smaller UD pulley! 20% with a cam, etc. It's all hype.

Fact is that a 20% increase in power and a flat line on a torque curve is PDG. But, like Jeff said ... no substitute for BOOST!
 

·
Registered
Joined
·
378 Posts
Discussion Starter · #8 ·
UnexplodedCow said:
Goes to show that your cam is the first part of the bottleneck in that engine considering the torque curve like that.
Explain if you will please.

It looked to me that it had a decent power band from 2800 up to 5500 RPM which is where I wanted it. I'm shifting ~ 5700 and it drops back in band. The Hp follows that to some degree bu Hp is derived from RPM and not from the torque.

Help me on this is I am misunderstanding it. The car pulls out of the corners very good.
 

·
Registered
Joined
·
7,066 Posts
When you have a flat torque curve like that from a low rpm...it's typical that you have a lower lift and duration cam. That cam typically comes on torque peak around 3400 rpm for a 1.9 engine from what I've seen, but you're reaching that much lower, indicating that your head is capable of flowing more air than the valves are allowing. The cam is responsible for opening the valve far enough to flow more. If you went with a higher lift, longer duration cam you'd definitely see more power. From the picture above, it looks like you're using a stock SPI cam. Am I right?
 

·
Registered
Joined
·
378 Posts
Discussion Starter · #11 ·
UnexplodedCow said:
When you have a flat torque curve like that from a low rpm...it's typical that you have a lower lift and duration cam. That cam typically comes on torque peak around 3400 rpm for a 1.9 engine from what I've seen, but you're reaching that much lower, indicating that your head is capable of flowing more air than the valves are allowing. The cam is responsible for opening the valve far enough to flow more. If you went with a higher lift, longer duration cam you'd definitely see more power. From the picture above, it looks like you're using a stock SPI cam. Am I right?
NO ... not a stock cam. However, I have been suspicious of it all along and wonder if the removal of the base circle material to reshape it actually works well. Some people won't even grind them and some will.???
Duration: 264/268
Duration @ .050: 204/208
Lobe Lift: .274"/.284"
Valve Lift: .452"/.468"
Lobe Center: 112

I know the head has ~ 10% better flow because I have a flow bench and did it myself. My thought was that the intake is the kink and it is running out of air.

All that said, however, what I was after was a great low end high torque engine. Hp does very little for this car and application.

Where can I see some dyno charts for a 1.9 or 2.0 engine?

Thanks
 

·
Registered
Joined
·
378 Posts
Discussion Starter · #16 ·
97DragScort said:
"removal of the base circle material to reshape it "

thats the main reason Ive been searching for NEW cast blanks for grinding.
I agree and if you find them I'll buy one. I looked all over and can't find any. If they take more than ~0.035" off I don't think the lifter will survive. To change the profile and gain lift I think they need to take about 0.050" off the base.

When I have time I will pull the cover and actually measure the lift as installed to see what it really is. The only other option is to weld up the lobes but that would cost ~ $500 just for the welding.

Not sure if the cam out of the HO engine would work if the pickup for the cam position sensor was put on it some way.

I will say this, however, the car pulls very good in the low end. I would really like to see a dyno run of a stock engine and then we would have some decent data.

If you can score those adj. cam pulleys I would like to buy one.
 

·
Registered
Joined
·
7,066 Posts
Rex said:
UnexplodedCow said:
When you have a flat torque curve like that from a low rpm...it's typical that you have a lower lift and duration cam. That cam typically comes on torque peak around 3400 rpm for a 1.9 engine from what I've seen, but you're reaching that much lower, indicating that your head is capable of flowing more air than the valves are allowing. The cam is responsible for opening the valve far enough to flow more. If you went with a higher lift, longer duration cam you'd definitely see more power. From the picture above, it looks like you're using a stock SPI cam. Am I right?
NO ... not a stock cam. However, I have been suspicious of it all along and wonder if the removal of the base circle material to reshape it actually works well. Some people won't even grind them and some will.???
Duration: 264/268
Duration @ .050: 204/208
Lobe Lift: .274"/.284"
Valve Lift: .452"/.468"
Lobe Center: 112

I know the head has ~ 10% better flow because I have a flow bench and did it myself. My thought was that the intake is the kink and it is running out of air.

All that said, however, what I was after was a great low end high torque engine. Hp does very little for this car and application.

Where can I see some dyno charts for a 1.9 or 2.0 engine?

Thanks
Ah, so you bought one of the Isky cams. I was curious how well they'd work. What's your compression ratio? Pulled a compression test yet? Have you messed with the exhaust at all? I know the CVH has a lot of low end torque, but something smells off here because those cam specs are extremely close to the 1st gen HO, which doesn't quite make the same low end torque. The bump in displacement helps, but I doubt that much.
 

·
Registered
Joined
·
1,909 Posts
Im waiting on EFP to get word back from the machine shop for the Adj Cam gears.... as soon as they get back to me, I'll post priceing.

Im feeling ya Rex, the biggest N/A gain is the cam and Im haveing 1 hell of a time finding a profile that I like.
 

·
Registered
Joined
·
378 Posts
Discussion Starter · #19 ·
NO ... I did not buy an Ishky cam. Isky is not reliable in my opinion and I won't deal with them which I said up front. I've had this cam for quite some time and it has been around for a long time. That's what makes the Isky BS about needing a cam to see what could be done with it and all the hype so funny.

That said, I'm pretty happy with the torque curve in itself and the car pulls hard our of the corners. The Hp won't help much. Without seeing a stock dyno run I can't really compare it however. The stock SPI is rated at 125# torque at 3750 and I am only up to ~ 138# but with a broad RPM range.

Interestingly, what I did discover doing 4 runs was that by adding 2 degrees of spark each time the power cam up. I stopped after 8 degrees then pulled the spark back out for the lower loads.

11:1 compression and I did a leakdown which is less than 3%. I have custom 3-2-1 headers. You will not that my ARF's are spot on at 12.4:1

I need someone to have a stock 2.0L SPI engine put on teh dyno.
 

·
Registered
Joined
·
7,066 Posts
What's the base ignition timing for the SPI? Stock for mine is 8 BTDC, and I've been running at 12 for some time without issue, although I've been running premium gas. Where did you get the cam from? It's definitely a low rpm torque-based one...still sounds like it's preventing the engine from breathing based on your compression, headflow work, and exhaust.
 
1 - 20 of 40 Posts
This is an older thread, you may not receive a response, and could be reviving an old thread. Please consider creating a new thread.
Top