427 Final Spec
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From: Bergen County, NJ Democrats, doing for the country what they did for Michigan
427 Final Spec
Here's the makeup of the 427.....comments welcome except to tell me I should have used different heads and I'm leaving power on the table. If that's the response, STFU.....
Now, the question I have is that I am using the stock computer. Does anyone believe I'll have a problem tuning?
Thanks
Block.......Dart SHP new block with two piece RMS
Crank.......Scat 4 inch stroke
Compression......10.5:1 static
Heads.......Dart Pro 1 Platinum heads 215CC with some porting and CNC to the combustion chambers to get to over 300CFM intake and about 215CFM exhaust 72CC chambers.
Cam......240/246 112* .575/.585 lift Custom Grind
Intake....Miniram with TPIS 58MM TB
40LB Bosch III injectors from FIC, new not rebuilt
Stall Converter (Petek) 2800 stall (street use)
3.07 rear
Headers.....1 3/4 inch long tube Exotic Muscle into a 3 inch exhaust, two high flow cats, and 3 inch X pipe. I think the headers are a little light, but it's what I have
1.6 Com Cam Pro Mags, 7/16 inch stud.
Typical misc parts.....Hydraulic roller lifters, chromo push rods, double roller timing chain...etc....misc stuff
Now, the question I have is that I am using the stock computer. Does anyone believe I'll have a problem tuning?
Thanks
Block.......Dart SHP new block with two piece RMS
Crank.......Scat 4 inch stroke
Compression......10.5:1 static
Heads.......Dart Pro 1 Platinum heads 215CC with some porting and CNC to the combustion chambers to get to over 300CFM intake and about 215CFM exhaust 72CC chambers.
Cam......240/246 112* .575/.585 lift Custom Grind
Intake....Miniram with TPIS 58MM TB
40LB Bosch III injectors from FIC, new not rebuilt
Stall Converter (Petek) 2800 stall (street use)
3.07 rear
Headers.....1 3/4 inch long tube Exotic Muscle into a 3 inch exhaust, two high flow cats, and 3 inch X pipe. I think the headers are a little light, but it's what I have
1.6 Com Cam Pro Mags, 7/16 inch stud.
Typical misc parts.....Hydraulic roller lifters, chromo push rods, double roller timing chain...etc....misc stuff
Last edited by jsup; Aug 18, 2008 at 04:39 PM.
Melting Slicks
Joined: Jan 2008
Posts: 2,065
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From: Jasper Texas
Looks like its going to be a nice streetable beast!
If I were you, I would have went with a bigger cam, and a solid roller as well. Higher compression, 3.73s out back...is that still a dana 36!
And a higher stall.
Of course, then it wouldn't be so steetable, but thats how I like 'em!
and a friendly suggestion, don't give that rear any traction!
If I were you, I would have went with a bigger cam, and a solid roller as well. Higher compression, 3.73s out back...is that still a dana 36!
And a higher stall. Of course, then it wouldn't be so steetable, but thats how I like 'em!
and a friendly suggestion, don't give that rear any traction!
Le Mans Master
Joined: Mar 2002
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From: Castro Valley Calif.
St. Jude Donor '03 thru '26
That's a nice combo John, I'd start thinking about gearing right now if'n I was you........you're gonna need a new rear end.
Since you want an all purpose car, you'll probably need 3.45s or better with that cam, otherwise you'll be lugging around the parking lot
edit: Oh yeah.........start saving for a tranny too!
Since you want an all purpose car, you'll probably need 3.45s or better with that cam, otherwise you'll be lugging around the parking lot
edit: Oh yeah.........start saving for a tranny too!
Thread Starter
Team Owner
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From: Bergen County, NJ Democrats, doing for the country what they did for Michigan
Looks like its going to be a nice streetable beast!
If I were you, I would have went with a bigger cam, and a solid roller as well. Higher compression, 3.73s out back...is that still a dana 36! And a higher stall.
Of course, then it wouldn't be so steetable, but thats how I like 'em!
and a friendly suggestion, don't give that rear any traction!
If I were you, I would have went with a bigger cam, and a solid roller as well. Higher compression, 3.73s out back...is that still a dana 36!
And a higher stall. Of course, then it wouldn't be so steetable, but thats how I like 'em!
and a friendly suggestion, don't give that rear any traction!
As to the cam, ,my specific instructions are to ensure an idle that will allow me to sit in traffic with the AC on and not overheat or bump all over, a nice little lope is OK.
Thread Starter
Team Owner
Joined: Oct 2004
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From: Bergen County, NJ Democrats, doing for the country what they did for Michigan
That's a nice combo John, I'd start thinking about gearing right now if'n I was you........you're gonna need a new rear end.
Since you want an all purpose car, you'll probably need 3.45s or better with that cam, otherwise you'll be lugging around the parking lot
edit: Oh yeah.........start saving for a tranny too!
Since you want an all purpose car, you'll probably need 3.45s or better with that cam, otherwise you'll be lugging around the parking lot
edit: Oh yeah.........start saving for a tranny too!
Race Director
Joined: May 2003
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Looks sweet! Won't be a grocery getter anymore. That's going to be close to 600chp with that cam, and a lumpy wake the neighbour's up idle!
Tune on the factory "atari" computer? Love to see you try tuning it!
What CR?
Tune on the factory "atari" computer? Love to see you try tuning it!
What CR?
Thread Starter
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From: Bergen County, NJ Democrats, doing for the country what they did for Michigan
Corky is running some sick times on his 434 I think it was with the older factory computer, which is 1/4 as fast if I remember correctly. I don't anticipate a problem, but I'm hoping for Alvin to respond, and hearing come comments here.
NOw, I understand I may not squeeze every last HP without the perfect computer, but so what.
CR about 10.5:1 May be 10.3, may be 10.6 but about 10.5 I need to run pump gas.
Race Director
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Money is NOT infinate. I am keeping an eye out for a D44. I am banking money for a new trans....The trans and rear are temporary...I'm hoping to get a season or two out of what I have.
As to the cam, ,my specific instructions are to ensure an idle that will allow me to sit in traffic with the AC on and not overheat or bump all over, a nice little lope is OK.
As to the cam, ,my specific instructions are to ensure an idle that will allow me to sit in traffic with the AC on and not overheat or bump all over, a nice little lope is OK.
I am going with more duration as well, but I still want to make mine streetable. Your cam won't be imo after talking to guys that have built big stroker's.
Hope it all works out, because this thing will rev up to 6600 I would think. Screamin big stroker!
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Race Director
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I have an email to Alvin at PCMfor less about the tune, as he did my initial tune.
Corky is running some sick times on his 434 I think it was with the older factory computer, which is 1/4 as fast if I remember correctly. I don't anticipate a problem, but I'm hoping for Alvin to respond, and hearing come comments here.
NOw, I understand I may not squeeze every last HP without the perfect computer, but so what.
CR about 10.5:1 May be 10.3, may be 10.6 but about 10.5 I need to run pump gas.
Corky is running some sick times on his 434 I think it was with the older factory computer, which is 1/4 as fast if I remember correctly. I don't anticipate a problem, but I'm hoping for Alvin to respond, and hearing come comments here.
NOw, I understand I may not squeeze every last HP without the perfect computer, but so what.
CR about 10.5:1 May be 10.3, may be 10.6 but about 10.5 I need to run pump gas.
I thought you were building this car for the street. It's ALOT easier to tune a car at WOT. You want it to idle, and to have good street manners. Maybe Corky will post in your thread. But I have a feeling he didnt drive his car 99.9% on the street, but I may be wrong.
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From: Bergen County, NJ Democrats, doing for the country what they did for Michigan
What aftermarket rad are you going to buy? You will set in traffic with the A/C on, that's not an issue. But it will bump.
I am going with more duration as well, but I still want to make mine streetable. Your cam won't be imo after talking to guys that have built big stroker's.
Hope it all works out, because this thing will rev up to 6600 I would think. Screamin big stroker!
I am going with more duration as well, but I still want to make mine streetable. Your cam won't be imo after talking to guys that have built big stroker's.
Hope it all works out, because this thing will rev up to 6600 I would think. Screamin big stroker!
Yeah, it will be a bit lopey.....
Melting Slicks
Joined: Jan 2008
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From: Jasper Texas
I feel ya' on the bump thing...I hate my solid roller sitting still, gives me a stomach ache!
But seriously, do not give the rear any traction, none! No WOT shifts, no launches, etc. Your car will end up like mine, not pretty!
But seriously, do not give the rear any traction, none! No WOT shifts, no launches, etc. Your car will end up like mine, not pretty!
Thread Starter
Team Owner
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From: Bergen County, NJ Democrats, doing for the country what they did for Michigan
I thought you were building this car for the street. It's ALOT easier to tune a car at WOT. You want it to idle, and to have good street manners. Maybe Corky will post in your thread. But I have a feeling he didnt drive his car 99.9% on the street, but I may be wrong.
IF, big fkn if, I have to go to a new computer, I will. I'm not convinced I have to.
Looking for advice if anyone has it. Experience.
At the end of the day, it's simply a function of holding the injectors open for a period of time, and dealing with the timing curve. So with bigger injectors, I don't see how it's a problem.
Racer
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From: Eden Utah
Your build is very similar to mine except I have a 406, my cam s a comp cam # 304 -HR 244-244 600 lift, I drive it every day--no problem, very streetable. I am using a Gen7 EFI so I am able to tune it how I want.
Wayne
Wayne
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From: Bergen County, NJ Democrats, doing for the country what they did for Michigan
Yeah, solid rollers do that. I went hydraulic roller as not to have to adjust valves all the time. Maintenance is easier with hydraulic roller....
Race Director
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I don't need an aftermarket radiator. My radiator and yours are different. My car has 30K miles. I had the rad out when I did the cam and it is in perfect condition. Remember, the 90 has two fans, yours has one (if I recall). The overheating issue was resolved by 1990 and carried forward to the LT1....
Yeah, it will be a bit lopey.....
Yeah, it will be a bit lopey.....
You will need an aftermarket rad if you want it to stay cool in traffic with the a/c on. If you want it, you have to spend money.
Melting Slicks
Joined: Jan 2008
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From: Jasper Texas
My car has the heater core bypassed, fans come on at 185, bigger radiator, aftermarket water pump, 180stat, and everything is clean. I still hit 200 from time to time...couldn't imagine what the stock radiator would be like.
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From: Bergen County, NJ Democrats, doing for the country what they did for Michigan
There was a significant change, I believe in 89, to the radiator and cooling system.
Do you have two fans as stock or 1?
If I need a new radiator, I'll get it. For now it's the stock one. If the car runs hot, I'll shut the air and turn on the heat, once, then I'll upgrade.
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From: Bergen County, NJ Democrats, doing for the country what they did for Michigan
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From: Athens AL
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Truth is you both might need a new radiator. Nothing "heavy duty" about the Z51 radiator thats doing anything if you ask me.
But your temperatures will show the need, one way or the other, so theres no point in debating it really.
Id like to see what the combo makes, and on down the line, I think bigger primaries would be helpful to power numbers if you were going to squeeze out every last HP you can.
But your temperatures will show the need, one way or the other, so theres no point in debating it really.
Id like to see what the combo makes, and on down the line, I think bigger primaries would be helpful to power numbers if you were going to squeeze out every last HP you can.
Thread Starter
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From: Bergen County, NJ Democrats, doing for the country what they did for Michigan
Truth is you both might need a new radiator. Nothing "heavy duty" about the Z51 radiator thats doing anything if you ask me.
But your temperatures will show the need, one way or the other, so theres no point in debating it really.
Id like to see what the combo makes, and on down the line, I think bigger primaries would be helpful to power numbers if you were going to squeeze out every last HP you can.
But your temperatures will show the need, one way or the other, so theres no point in debating it really.
Id like to see what the combo makes, and on down the line, I think bigger primaries would be helpful to power numbers if you were going to squeeze out every last HP you can.