Sounds like your converter is giving up a lot then. I was at 5750rpm at 134mph with 27.5" tires. Converter can make or break you when running a small hydraulic cam.
Max Rpm Stroker Motor
- Thread starter seeya v6
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Sounds like your converter is giving up a lot then. I was at 5750rpm at 134mph with 27.5" tires. Converter can make or break you when running a small hydraulic cam.
Personally if you were only looking for 130mph (about 580whp) id have chosen a smaller turbo and kept iron heads. Keep in mind if you are running a head with more flow then you need to rev more to take advantage of the flow capabilities. 6000 rpm should put you in the 9's at nearly 140mph.
With a very high peak cylinder pressure. Have a zipper on those head gaskets.
seeya v6. Are you running a stock block?
Your still limited by the exhaust side. Both flow the same on the exhaust side. What mph did 550whp give you?
Not as high as you would think. On an 8:1 engine he could push it to 40psi on good fuel before he hit the threshold. Not going to happen with out holding the wastegate shut with external pressure though
Trying to accomplish a particular target hp with less rpm, with a given displacement, requires more cylinder pressure. Static and dynamic CR really has nothing to do with 'that particular relationship'.
You can lower static CR so that you can run more boost, but the end result is the same cylinder pressure requirement to obtain a target hp level.
You can trade cylinder pressure for rpm and have the same hp target.
You can lower static CR so that you can run more boost, but the end result is the same cylinder pressure requirement to obtain a target hp level.
You can trade cylinder pressure for rpm and have the same hp target.
...and loss of drivability if that is of any importance. Which over 90% of the guys on here drive theirs regularly. Ill take the engine that requires 28-30psi to make 700hp for a street driver vs. one that requires 7000rpm but will do it at 18-20psi. As for any instance where $ doesnt matter you build it for both rpm and boost and run the best fuel you can. Most of the sigs i see on here the guys arent even close to having a cylinder pressure issue.
If that were the case, then why are head gaskets such a hot topic on this board?
Actually, the drivability is not bad at all. I guess I'll have to make a vid of some normal street driving with my 'radical' setup.
Because most on here dont have the tuning ability or the tools to be able to run one of these engines near the edge.
You would need to raise the boost and rpm to take advantage of the larger turbine. Can you post some converter slip numbers at different rpm's?
I don't understand why most people are afraid to rev their engine. Hydraulic lifters are good for at least 6,500 rpm. Why give up that extra rpm range with these small cams? If I were running a budget valvetrain, I would at the least take it up to its limit. That's some easy hp that people are letting just sit there. It wouldn't take too much more camshaft to tap into it.
imo, yes
But most of the cars that I see with 224/224 type cams a mainly used for track purposes. I'm going to take my car to the track to tune and most likely take it back when I redo my rear/suspension and crank the boost up but other than that I'll be on the street. Soooo?????
JDSfastGN
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Its not a small cam imo, I am going to be running a 210/215. Its a medium cam, a large cam is 220+ imo. For your 250 ci engine it may be considered "small" I guess. Look in the thread in the engine tech section where its asked what roller most of the TSM guys are running and most are running durations and lifts comparable to the 210/215.
To me a large (racing) cam doesn't start until 252 @ .050".
A medium cam would be 225, maybe 230 to 252 @ .050".
anything below 225 @ .050" is a small cam.
This is just my humble opinion.
I've run 252 and presently 242 @ .050 int. and there is just a small difference between the two with the heads I'm using. At 2000 rpm under a light steady load it's completely streetable. The low speed cruise street manners is really not much different than a 220. Not saying everyone should jump up to a 242, but it's just showing you that a lot is being left on the table with these small cams.
To me a 210 is just a pinch better than a stock cam. You could do better for something that's going to be mostly a street car.
Don't be afraid to let that engine breathe.
A medium cam would be 225, maybe 230 to 252 @ .050".
anything below 225 @ .050" is a small cam.
This is just my humble opinion.
I've run 252 and presently 242 @ .050 int. and there is just a small difference between the two with the heads I'm using. At 2000 rpm under a light steady load it's completely streetable. The low speed cruise street manners is really not much different than a 220. Not saying everyone should jump up to a 242, but it's just showing you that a lot is being left on the table with these small cams.
To me a 210 is just a pinch better than a stock cam. You could do better for something that's going to be mostly a street car.
Don't be afraid to let that engine breathe.
