355 dyno with raised rev limiter?

INTMD8 · #1 12-08-2009, 06:16 PM

Just wondering if anyone has a dyno sheet of a 355 with a raised rev limiter? The dyno sheet Gothspeed posted a while back shows the engine peaking around 8500rpm.

I would like to see a dyno of one pulled to 9000+ if one is out there as I would like to know where the power starts to fall off.

Seems like the car would be quite a bit faster if it was shifted a few hundred rpm past peak hp rather than right on top of it.

sambomydog · #2 12-09-2009, 03:48 AM

My guess is that this thread may be full of assumptions as opposed to hard facts. Its it takes of at all.
There's one car that i have heard of with a rev limiter set at 10,000rpm, and thats the ex Shuey (F1 fame) car. Although allegedly it also had factory hot cams.
But i agree it would be interesting to see the dyno sheets.

**ernie** · #3 12-09-2009, 11:08 AM

The proper cams are a must to really make it work at those rpm's, especially if you wanna spin it to 10 grand. Then there is the question of the valve train? How well would the stock valve train hold up at those rpm's.

As a wise old man once said, "RPM stands for, Ruins Peoples Motors".

INTMD8 · #4 12-09-2009, 11:25 AM

Quote:

Originally Posted by ernie

The proper cams are a must to really make it work at those rpm's, especially if you wanna spin it to 10 grand. Then there is the question of the valve train? How well would the stock valve train hold up at those rpm's.

As a wise old man once said, "RPM stands for, Ruins Peoples Motors".

Thats why I would like to see a graph. If the stock cams peak at 8500 an have very little drop-off at 9000 while showing no signs of valvetrain instability than they are up to the task IMO.

Mitch Alsup · #5 12-09-2009, 03:42 PM

I have a dyno that looks remarkably like gothspeeds' (which is why I am remakring on it....) In addition I had the dyno operator run the car right up to the fuel cut off of the ECU.

The mechanical item that limits the RPMs of the F355 engine are the hydraulic lifters, the ECU cutrs in before you get there). All of the other components can be used to significantly higher RPM ranges*. However, If you do want to look for another 1000 RPMs, you need to shed the hydraulic lifters and get some shim under bucket arrangement. The hydraulic lifters are already costing power at the standard redline.

(*) given that you are aware of how wear increases cubically with RPMs.

**gothspeed** · #6 12-09-2009, 04:00 PM

I would be very happy with a 9100 RPM ECU cutoff ...........

Rifledriver · #7 12-09-2009, 04:47 PM

Quote:

Originally Posted by Mitch Alsup

I have a dyno that looks remarkably like gothspeeds' (which is why I am remakring on it....) In addition I had the dyno operator run the car right up to the fuel cut off of the ECU.

The mechanical item that limits the RPMs of the F355 engine are the hydraulic lifters, the ECU cutrs in before you get there). All of the other components can be used to significantly higher RPM ranges*. However, If you do want to look for another 1000 RPMs, you need to shed the hydraulic lifters and get some shim under bucket arrangement. The hydraulic lifters are already costing power at the standard redline.

(*) given that you are aware of how wear increases cubically with RPMs.

355 was designed for a 10k redline and is the reason they decided to go with titanium rods. During durability testing they found timing belt life unacceptably short at 10k rpm so the redline was lowered in the ecu. No other design or component changes were made. Later it was found out the early rods had a stress riser in the area of the rod bolts leading to some failures. The rods had a very minor redesign in late 95 or early 96.

FandLcars · #8 12-09-2009, 04:59 PM

Quote:

Originally Posted by Rifledriver

During durability testing they found timing belt life unacceptably short at 10k rpm

But I bet they looked really good!

INTMD8 · #9 12-09-2009, 05:23 PM

Quote:

Originally Posted by Rifledriver

355 was designed for a 10k redline and is the reason they decided to go with titanium rods. During durability testing they found timing belt life unacceptably short at 10k rpm so the redline was lowered in the ecu. .

Interesting. The gates racing timing belts could have been helpful but this was there response when I inquired about them-

"James,
Gates does not provide timing belts for the Ferrari F355 model. The popularity is low from Gates viewpoint and not cost effective to build these timing belts.
Regards, APA Team"

**f355spider** · #10 12-09-2009, 05:46 PM

Quote:

Originally Posted by INTMD8

Interesting. The gates racing timing belts could have been helpful but this was there response when I inquired about them-

"James,
Gates does not provide timing belts for the Ferrari F355 model. The popularity is low from Gates viewpoint and not cost effective to build these timing belts.
Regards, APA Team"

14,000 355's worldwide....how many Corollas? Half a million?

sambomydog · #11 12-09-2009, 05:58 PM

Quote:

Originally Posted by Rifledriver

355 was designed for a 10k redline and is the reason they decided to go with titanium rods. During durability testing they found timing belt life unacceptably short at 10k rpm so the redline was lowered in the ecu. No other design or component changes were made. Later it was found out the early rods had a stress riser in the area of the rod bolts leading to some failures. The rods had a very minor redesign in late 95 or early 96.

Did not know that, thanks for posting

INTMD8 · #12 12-09-2009, 06:03 PM

Quote:

Originally Posted by f355spider

14,000 355's worldwide....how many Corollas? Half a million?

Not sure but I think a product called "racing timing belts" isn't likely targeted towards Corollas.

I would think that entire product line would be relatively low volume.

Rifledriver · #13 12-10-2009, 11:38 AM

Quote:

Originally Posted by INTMD8

Interesting. The gates racing timing belts could have been helpful but this was there response when I inquired about them-

"James,
Gates does not provide timing belts for the Ferrari F355 model. The popularity is low from Gates viewpoint and not cost effective to build these timing belts.
Regards, APA Team"

Wouldn't matter. Timing belts on race motors are not designed or intended to go 30,000 miles.

INTMD8 · #14 12-10-2009, 11:53 AM

Quote:

Originally Posted by Rifledriver

Wouldn't matter. Timing belts on race motors are not designed or intended to go 30,000 miles.

Maybe not but the great number of these cars reach the time limit on the belt before mileage in which case I would think a stronger belt could be cheap insurance on a higher rpm application.

sambomydog · #15 12-10-2009, 12:16 PM

Quote:

Originally Posted by Mitch Alsup

The mechanical item that limits the RPMs of the F355 engine are the hydraulic lifters, the ECU cutrs in before you get there). All of the other components can be used to significantly higher RPM ranges*. However, If you do want to look for another 1000 RPMs, you need to shed the hydraulic lifters and get some shim under bucket arrangement. The hydraulic lifters are already costing power at the standard redline.

Quote:

Originally Posted by Rifledriver

355 was designed for a 10k redline and is the reason they decided to go with titanium rods. During durability testing they found timing belt life unacceptably short at 10k rpm so the redline was lowered in the ecu. No other design or component changes were made.

I have just noticed that there are two conflicting theories/facts here.
Rifledriver said that no other design or component changes were made, for the engine to rev to 10,000rpm.
Mitch Alsup said that the mechanical item that limits the F355s RPM are the hydraulic lifters.
Which is true of the two statements?

Rifledriver · #16 12-10-2009, 02:23 PM

Quote:

Originally Posted by sambomydog

I have just noticed that there are two conflicting theories/facts here.
Rifledriver said that no other design or component changes were made, for the engine to rev to 10,000rpm.
Mitch Alsup said that the mechanical item that limits the F355s RPM are the hydraulic lifters.
Which is true of the two statements?

I got my information from Ferrari Spa.

You decide.

sambomydog · #17 12-10-2009, 02:52 PM

Quote:

Originally Posted by Rifledriver

I got my information from Ferrari Spa.

You decide.

Mmm now thats a tricky one because just like politicians, i believe very little that come out of Ferrari Spa

rarther in the same way you beleve very little that comes out of FNA

redryder · #18 12-10-2009, 02:59 PM

Well, if you had gone to the factory years ago you would have actually seen the 355 engines being tested at 10K rpm's.

Rifledriver is dead on with what he said.