rage2

</font><blockquote><font size="1" face="Verdana,Tahoma,Helvetica">quote:</font><hr /><font size="2" face="Verdana,Tahoma,Helvetica">Originally posted by BoostGuy951:
<strong>I have no idea of the max rpm the stock head/valvetrain can support. Someone please divulge this info.</strong></font><hr /></blockquote><font size="2" face="Verdana,Tahoma,Helvetica">I've ran many track events at 7000rpm without any problems associated with high revs (valve float, broken stems, etc.) That was with my 2.5 high revvin' motor from last year .

BoostGuy951

</font><blockquote><font size="1" face="Verdana,Tahoma,Helvetica">quote:</font><hr /><font size="2" face="Verdana,Tahoma,Helvetica"> Oringinally Posted by rcldesign:
See signature... its made out of a 2.5L block. Pistons are cut for 8:1 compression with 16V head. Custom this that and the other thing. BTW, Huntley is building it for me. They also offer a 3.1L, 3.0L, 3.2L, 3.4L, 2.8L, etc.
</font><hr /></blockquote><font size="2" face="Verdana,Tahoma,Helvetica">What is the bore of this motor? I was told by a tuner that 104mm was the most you could safley go bore-wise out of the 2.5 block. Assuming the 3.0 crank is being used , I assume you are using one hella-large piston to get 3.2 liters. Does the 16v Head have a larger cc combustion chamber?

rcldesign

106mm bore. I'm not too sure about that maximum 104mm limit... Huntley, Anderson, and I'm sure others use a 106mm bore for their 2.8L and 3.1L motors - of course the cylinders are being sleeved with ChMo. So the motor would be in the 3.1L range... until it was stroked.

I can't remember the combustion chamber volume... I had a 16V head sent out to be measured to make sure the numbers were right in the compression calculations with the rods and pistons.

BoostGuy951

Hmm, I wonder why I was told 104mm is the practical limit. Maybe that is with iron sleeves. Possibly using the original bore would allow for a larger piston.

Some questions about sleeves vs Nikasil Treatment...

Which is Cheaper, which is more durable?

David Floyd

</font><blockquote><font size="1" face="Verdana,Tahoma,Helvetica">quote:</font><hr /><font size="2" face="Verdana,Tahoma,Helvetica"> Hmm, I wonder why I was told 104mm is the practical limit. Maybe that is with iron sleeves. Possibly using the original bore would allow for a larger piston</font><hr /></blockquote><font size="2" face="Verdana,Tahoma,Helvetica">Most likely just builder preference

DFASTEST951

RCLDESIGN,

Yes, it's run on race fuel. Nothing else for safety reasons of my own. It's built to run on pump gas though. By street legal means that I started the car in the morining and drove six minutes to a smog station and it passed with no cat. It runs that good. Completely stock interior. Outside pic is on Powerhaus.com. I can outpull a Venom 550 Viper. When your car is done, come on into Vegas, I'll buy lunch or dinner. We'll go for a ride. You'll ****, I swear...

rcldesign

DFASTEST951 -

Passed smog with no cat? Wow. Let me repeat that... wow. In NV do they just do a sniffer and no visual inspection? I'll actually be in Vegas in August with a bunch of my friends, but I think we're all going to fly in (since air fare from San Diego is super cheap). With my motor, I hope to be in the low to mid 400's, running 91 octane gas (There is a car that just left the Huntley shop that made very close to 400 at 15 psi from a 2.8L with an 8V head... I'll have a bigger motor, and I am going to try and run ~17 psi on the street, so that's why I'm expecting somewhat similar performance). I'll drop you an email when the time gets closer. My car is also complete interior (and a $2K+ stereo system). Some of it needs to be redone (like dash, etc.), and it needs paint very badly.... anyway, I'll email you in August.

rage2

DFASTEST951 - I'd like to check out your car next time I'm out there. I visit vegas yearly for CES... 6 months away . I'm very curious how well the 3L motor works in terms of low end TQ. I'll even rent a viper and run with ya .

DFASTEST951

hey guys, I'd love to meet up with you both. Come on in and email, call me anytime. Love to see the cars, go for drives. rcldesign, when i took the car in for smog, they just did the sniffer and didn't check for the cat. A lot of times they don't. so damn hot here they just get you in and out asap so they can get back into their air conditioned office. Rage, your car sounds like a screamer. Unbelievable for a 2.5
Do you run it at 25psi all the time? How many miles on it?

rcldesign

I can believe rage's numbers. If he has timing control, is running an HR stage III turbo (pretty much the biggest thing you can stick on a 2.5L), and he's running 25 psi, I would guess he'd dyno in between 390 - 450 depending on temperature and humidity, etc.

rage - do you have a cam in there? That turbo should be able to pull close to redline (7000 rpm) - if you have the cam for it <img border="0" title="" alt="[Wink]" src="wink.gif" />

rage2

I have full timing and fuel control (SDS EFI standalone). I run it at 12psi on the street on pump gas, thats the most I can go without spiking EGT's. 25psi is for track only, using VP MS103 race gas. I've actually ran 28psi several times at the track, which is the effective limit of 103 octane fuel, but never a drag race so I have no clue what the timeslip would look like. Stock cams, and yes, it pulls hard all the way to 7000rpm .

BoostGuy951

1989 944s have the 104mm bore of the S2 and 968, with the 78.9mm stroke of the non-S2/968s.
This seems like a decent platform for a big bore 2.7 turbo, or a 3.0 liter turbo if you get the 3.0 crank. I am interested in this option because my dad has two 1989 944s. I might be able to work something out to get one of those motors.

Anybody running a 2.7 block or head?