Project 3400 Roller Cam Block (Page 6/82)
perry rhodan JUN 08, 06:49 AM
I wonder if the "restriction problem" dont come from the induced turbulence from the several brutal change in flow direction the air have to do when going down to the cylinder...these runner design are very snake like, and the change in direction are not progressive and are very drastic. So farter you go down and change of direction you add to the air stream, more and more velocity slow down and turbulance you add.

I think it was discussed earlier here on pennock.

The best is not only enlarge the runner cross section, but like in racing, have the smoother route, the smoother "racing apex" for the air when it go thru the turn.

Hope to ear from your project soon Lou_Dias
lou_dias JUN 08, 07:26 AM
On this car:
The court clerk has my $1500 in escrow so the mechanic's lawyer is just being a dick about giving me my car despite the fact that we have a signed agreement. We have a deposition on July 9th. As I see it this is going to trial unless they offer me alot of money before then. Trial will probably be in October.

In the meantime, I should receive my new (bought from Voytek) Fiero on Wednesday. It's a 3.1 Turbo. When/if it blows up, it will become a 3400 w/Fiero intake with a turbo. I need to find a way to get this baby to Darth for some serious tuning...

Fyi, turbulence is important for low RPM power. Smoothness doesn't generate enough turbulence until you have high velocities, so based on the application, I wouldn't say that "restriction" is bad as I don't intend to have this motor over 5500rpm to often. Basically you want it smooth until just before it goes into the combustion chamber.

As for my cut intake, the direction change is the same as stock but by shortening the straight vertical sections, I was able to have the machinist smoothen more area around where it does curve. Also it makes that direction change 1 smoother continuous change instead of 2 with a small straight section inbetween. I lost a total of about .7" which doesn't sound like much, but a shorter intake is a shorter intake. 1fst2m6 proved this can work. He did tell me to shorten the area where the lower meets the middle manifold, but that cause the gaskets to not line up - big no-no. Luckily I had a spare middle intake.

Edit:
Actually look at my first post where I post a pic of the injector area...tell me how that compares to the pic above. Also, the upper and middle intakes have been smoothened further than what is pictured.

[This message has been edited by lou_dias (edited 06-08-2007).]

88 Silver Formula JUN 08, 06:22 PM
OCTOBER!!!! GOD OH MIGHTY!! MAN!! and this guy physically has your car this whole time???? im seeing hireing a brick thrower and beat that car to hell...would look bad on him + gives your killer insurence money for your turbo 3.1....hee?? lol
rjblaze JUN 08, 11:40 PM


Edit:
Actually look at my first post where I post a pic of the injector area...tell me how that compares to the pic above. Also, the upper and middle intakes have been smoothened further than what is pictured.

[/QUOTE]

Great thread! Except for your legal problems (Lawyers and bad mechanics suck, don't they?) I will be following this as I am also planning a 3400 roller w/turbo built just about the identical way. BTW nice port job removing the injector boss restriction. I got a few questions:

Is it really necessary to change the pistons? I wanted to use the stock 3400's with the thinner head gasket.....should be around 7.8:1 or so. (Stock gaskets / stock pistons / 3.4 cast heads should be about 7.66:1 for turbo)

What would be a good turbo to use? I have been looking at the Garrett GT3071.

Good luck with this......I am keeping tuned!
88 Silver Formula JUN 09, 03:30 PM
...for a turbo i do believe that the stock pistons..fiero or 3.4 cast heads and 3400 head geasket would work..if you wanted to raise compression slightly then use camaro 3.4 gaskets.
Will JUN 09, 11:11 PM

quote
Originally posted by lou_dias:
As for my cut intake, the direction change is the same as stock but by shortening the straight vertical sections, I was able to have the machinist smoothen more area around where it does curve. Also it makes that direction change 1 smoother continuous change instead of 2 with a small straight section inbetween. I lost a total of about .7" which doesn't sound like much, but a shorter intake is a shorter intake. 1fst2m6 proved this can work. He did tell me to shorten the area where the lower meets the middle manifold, but that cause the gaskets to not line up - big no-no. Luckily I had a spare middle intake.



Not understanding your thinking. The air going from the upper manifold turns 90 degrees to go into the middle and then a further 45+ to go across to the opposite bank. You think that taking this pair of bends and turning them into one tighter 135+ degree bend is going to help things? I think that's bass ackwards.

0.7" of runner shortening is going to do about jack squat for your powerband. You really need to change the runner length 15% or more to see a significant difference.

What is it with the Fiero intake? The Gen III heads and intake are VASTLY superior to the Fiero intake and will give you much more power with the same boost as the iron heads/intake.
lou_dias JUN 11, 08:20 AM

quote
Originally posted by Will:
Not understanding your thinking. The air going from the upper manifold turns 90 degrees to go into the middle and then a further 45+ to go across to the opposite bank. You think that taking this pair of bends and turning them into one tighter 135+ degree bend is going to help things? I think that's bass ackwards.

0.7" of runner shortening is going to do about jack squat for your powerband. You really need to change the runner length 15% or more to see a significant difference.

What is it with the Fiero intake? The Gen III heads and intake are VASTLY superior to the Fiero intake and will give you much more power with the same boost as the iron heads/intake.



My thinking is that a .7" tunnel is wasted space. If the air is already turning 90 degrees and has to go 3/4" and turn 45 degrees, why not just keep it turning? What advantage is there to that tunnel? Also, in eliminating that excess length it allowed the machinist to smoothen the upper intake deeper than normal as it approaches the initial turn. It also allowed the middle intake to be completely ported and smoothened. I will be dynoing it so once that is done then we can really determine another view on the limits of the stock intake. I would like to do something about the neck on the upper intake but neither of the 2 machinists I spoke to wanted to do anything radical for fear of irreparable damage. I'll have to pick up a spare one of these days and tell them to go to town on it...
lou_dias JUL 05, 09:22 AM
Lawyer has sent a formal letter asking for a date for me to pick up my car from the crook.
Also, on Monday, July 7th, I have a desposition to give at their lawyer's office.
perry rhodan AUG 31, 07:35 AM
So, any progress on the project or at least, did you finally got home with the car?

[This message has been edited by perry rhodan (edited 08-31-2007).]

lou_dias AUG 31, 09:11 AM
LOL, I just got a letter from my lawyer yesterday.

The court clerk has been slow to deposit my money in an escrow account because someone was out sick for 3 months and is backed up.

So my lawyer kindly asked the mechanic's lawyer to release the car with assurances that he has my money otherwise he will file the appropriate motion which I wish he had done way back in January!!!! So I should have an answer to that next week.