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Exhaust cutout

  • Thread starter Thread starter pj1
  • Start date Start date Jul 24, 2005
P

pj1

Member
Jan 1, 2003
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Calif
Jul 24, 2005
#1
  • Jul 24, 2005
  • #1
I'm about to convert to a 5 speed (from atm), put a rack & pinion steering, headers and exhaust.

This is a mountain car, 40-70mph turns, fun stuff. The engine currently is a stalk 289. Global West suspensions and stuff. I'm thinkin' of a 302 stroker as that might be best for pulling out of a turn.

The exhaust system will probably be 2 1/4 inch x pipe with (FlowMaster 2chamb?).


HERE's the question:

I'd love to put a set of electric cutouts on the the exhaust. Lots of reasons, all of them stupid.

I can't find one for 2 1/4. I can find 2 1/2. Maybe i could shim the 2 1/2 down to a 2 1/4 size?

Thanks
PJ
 

iskwezm

10 Year Member
May 24, 2005
4,159
20
79
Rowland Heights,California
Jul 25, 2005
#2
  • Jul 25, 2005
  • #2
why are you gonna choke it with a 2 1/4?????At least run a 2 1/2.
 
P

pj1

Member
Jan 1, 2003
57
0
6
Calif
Jul 25, 2005
#3
  • Jul 25, 2005
  • #3
My hopes for a future engine build calls for a reasonably mild engine. My understanding from reading other posts is that 2.5 inch pipes might be a little big and hurt torque for a 302 stroker. I'd go with a bigger engine, but I'm worried about getting too much weight up front.

This car's primary use is on windy mountain roads
Using 2.5 inch pipes solves the problem of finding a cutout of the right size as I could go with the 2.5 inch cutouts from

http://www.buickgn.com/electricexhaustcutout.htm
 

brianj5600

Active Member
Sep 19, 2003
1,964
2
39
Middle TN
Jul 25, 2005
#4
  • Jul 25, 2005
  • #4
Is the goal to get more hp with open exhaust? It seems like more air out = more air in. Does that mean that you will need to rejet the car when you open the electric cut outs? Turbo Buick are efi which makes adjustments mixture and turbos work on pressure differential so less back pressure helps even more. Would it make me a hippie if I said "open exhaust ruins the reason most people go to the mountains?"
 
M

mustangman70

Founding Member
Dec 30, 2001
1,235
1
0
St pete, Florida
Jul 25, 2005
#5
  • Jul 25, 2005
  • #5
2.5 wont be too big for that motor
 

LMan

Founding Member
Aug 10, 2002
1,246
0
0
Mom's basement
Jul 25, 2005
#6
  • Jul 25, 2005
  • #6
get 2.5s
 

iskwezm

10 Year Member
May 24, 2005
4,159
20
79
Rowland Heights,California
Jul 25, 2005
#7
  • Jul 25, 2005
  • #7
pj1 said:
My understanding from reading other posts is that 2.5 inch pipes might be a little big and hurt torque for a 302 stroker.
Click to expand...
You might wanna stay away from those post,somebody is REALLY wrong.
 
P

pj1

Member
Jan 1, 2003
57
0
6
Calif
Jul 25, 2005
#8
  • Jul 25, 2005
  • #8
Thanks. That is the information that I was lookin' for.

The only reason for cut outs is that I can do it and it might be fun. No rational thinking here.

These mountain roads are our commute roads and it's a real race track in the morning and evening.
Sure beats the freeways


Thanks
PJ
 

iskwezm

10 Year Member
May 24, 2005
4,159
20
79
Rowland Heights,California
Jul 25, 2005
#9
  • Jul 25, 2005
  • #9
pj1 said:
Thanks. That is the information that I was lookin' for.

The only reason for cut outs is that I can do it and it might be fun. No rational thinking here.

These mountain roads are our commute roads and it's a real race track in the morning and evening.
Sure beats the freeways


Thanks
PJ
Click to expand...
where do you live at?
 
P

pj1

Member
Jan 1, 2003
57
0
6
Calif
Jul 25, 2005
#10
  • Jul 25, 2005
  • #10
Boulder Creek California.

We're near Big Basin state park. Big redwoods and cool stuff.

We've got this hiway 9 and Skyline that snakes up thru the mountains to the San Francisco Bay Area. They should make it a National Park for Fast Cars and motorcycles.
It's about the road.


Everybody's opinions on pipe size really help me figure this out.

PJ
 

iskwezm

10 Year Member
May 24, 2005
4,159
20
79
Rowland Heights,California
Jul 25, 2005
#11
  • Jul 25, 2005
  • #11
pj1 said:
Boulder Creek California.

We're near Big Basin state park. Big redwoods and cool stuff.

We've got this hiway 9 and Skyline that snakes up thru the mountains to the San Francisco Bay Area. They should make it a National Park for Fast Cars and motorcycles.
It's about the road.


Everybody's opinions on pipe size really help me figure this out.

PJ
Click to expand...
oh,your way up north.
 
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