3" Exhaust Systems.....
Team Owner
Joined: Apr 1999
Posts: 21,953
Likes: 1,445
From: Reno Nevada
2024 C3 of the Year Finalist- Modified
Let's look at your posted profile - It would give better answers.
1969 Corvette Coupe/ 388 Stroker 373 RWHP, 452 RWTQ, 11.62 1/4 mi.
Engine combo:
Carb - Mighty Demon 825
Intake - RPM Air Gap
Heads - AFR 195's, competition ported
Cam - Comp Cams 286HR hyd. roller
C.R. - 10.9 w/ flat top pistons
Other goodies:
1.65 Comp Cams roller rockers
4.11 Rear , Art Carr 10" 2900 RPM stall converter
Wilwood brakes (Dyna-Lite calipers)
380 LB. VBP composite rear spring
My first answer is that you are at the point where you are maxed out for your combo if everything is working right
You can do little things like 3800 stall and go to a single plane or you can get 3 inch exhausts or go to a bigger solid roller cam.
The problem comes back to where can I go to get the most bang for the buck???? At some point every small HP gain cost allot more.!
This is the whole reason why over the years that I have said to do the 3.875 stroker crank first. Not the wimpy 383 -388 ci
The next step - like me is now that you have all this small block stuff is to just use it on another bigger small block then you end up with these 434-472 ci small blocks.
That really require custom cross members and full 3 inch dual exhaust systems.
Actually your best bang for the buck is keep the 388 and drop the compression down to 8.6ish with a blower
1969 Corvette Coupe/ 388 Stroker 373 RWHP, 452 RWTQ, 11.62 1/4 mi.
Engine combo:
Carb - Mighty Demon 825
Intake - RPM Air Gap
Heads - AFR 195's, competition ported
Cam - Comp Cams 286HR hyd. roller
C.R. - 10.9 w/ flat top pistons
Other goodies:
1.65 Comp Cams roller rockers
4.11 Rear , Art Carr 10" 2900 RPM stall converter
Wilwood brakes (Dyna-Lite calipers)
380 LB. VBP composite rear spring
My first answer is that you are at the point where you are maxed out for your combo if everything is working right
You can do little things like 3800 stall and go to a single plane or you can get 3 inch exhausts or go to a bigger solid roller cam.
The problem comes back to where can I go to get the most bang for the buck???? At some point every small HP gain cost allot more.!
This is the whole reason why over the years that I have said to do the 3.875 stroker crank first. Not the wimpy 383 -388 ci
The next step - like me is now that you have all this small block stuff is to just use it on another bigger small block then you end up with these 434-472 ci small blocks.
That really require custom cross members and full 3 inch dual exhaust systems.
Actually your best bang for the buck is keep the 388 and drop the compression down to 8.6ish with a blower
Melting Slicks
Joined: Dec 1999
Posts: 2,116
Likes: 156
From: Mid West
Cruise-In III Veteran
Some shops will do 3", but if you can weld MIG or TIG then you can fabricate one pretty easy as long as you can get your car up in the air enough. I purchased most of my bends from Dr. Gas. They have a whole assortment of bends, sizes, and even oval pipes.
I tack welded mine as I fitted it into the chassis. Once everthing was where I wanted it and I had clearance so it wouldn't rattle I just made a few more tack welds, removed the whole system, and finished the welding out on the floor. The reinstall was a snap at that point. Took about 2 days start to finish, and that includes fabricating my own hangers.
I tack welded mine as I fitted it into the chassis. Once everthing was where I wanted it and I had clearance so it wouldn't rattle I just made a few more tack welds, removed the whole system, and finished the welding out on the floor. The reinstall was a snap at that point. Took about 2 days start to finish, and that includes fabricating my own hangers.
Thread Starter
Safety Car
Joined: Oct 2004
Posts: 3,923
Likes: 733
From: Youngstown Ohio
Let's look at your posted profile - It would give better answers.
1969 Corvette Coupe/ 388 Stroker 373 RWHP, 452 RWTQ, 11.62 1/4 mi.
Engine combo:
Carb - Mighty Demon 825
Intake - RPM Air Gap
Heads - AFR 195's, competition ported
Cam - Comp Cams 286HR hyd. roller
C.R. - 10.9 w/ flat top pistons
Other goodies:
1.65 Comp Cams roller rockers
4.11 Rear , Art Carr 10" 2900 RPM stall converter
Wilwood brakes (Dyna-Lite calipers)
380 LB. VBP composite rear spring
My first answer is that you are at the point where you are maxed out for your combo if everything is working right
You can do little things like 3800 stall and go to a single plane or you can get 3 inch exhausts or go to a bigger solid roller cam.
The problem comes back to where can I go to get the most bang for the buck???? At some point every small HP gain cost allot more.!
This is the whole reason why over the years that I have said to do the 3.875 stroker crank first. Not the wimpy 383 -388 ci
The next step - like me is now that you have all this small block stuff is to just use it on another bigger small block then you end up with these 434-472 ci small blocks.
That really require custom cross members and full 3 inch dual exhaust systems.
Actually your best bang for the buck is keep the 388 and drop the compression down to 8.6ish with a blower
1969 Corvette Coupe/ 388 Stroker 373 RWHP, 452 RWTQ, 11.62 1/4 mi.
Engine combo:
Carb - Mighty Demon 825
Intake - RPM Air Gap
Heads - AFR 195's, competition ported
Cam - Comp Cams 286HR hyd. roller
C.R. - 10.9 w/ flat top pistons
Other goodies:
1.65 Comp Cams roller rockers
4.11 Rear , Art Carr 10" 2900 RPM stall converter
Wilwood brakes (Dyna-Lite calipers)
380 LB. VBP composite rear spring
My first answer is that you are at the point where you are maxed out for your combo if everything is working right
You can do little things like 3800 stall and go to a single plane or you can get 3 inch exhausts or go to a bigger solid roller cam.
The problem comes back to where can I go to get the most bang for the buck???? At some point every small HP gain cost allot more.!
This is the whole reason why over the years that I have said to do the 3.875 stroker crank first. Not the wimpy 383 -388 ci
The next step - like me is now that you have all this small block stuff is to just use it on another bigger small block then you end up with these 434-472 ci small blocks.
That really require custom cross members and full 3 inch dual exhaust systems.
Actually your best bang for the buck is keep the 388 and drop the compression down to 8.6ish with a blower
Melting Slicks
Joined: Dec 1999
Posts: 2,116
Likes: 156
From: Mid West
Cruise-In III Veteran
Actually, that profile is history since the demise of the 388" stroker... (search old thread "Worse than Head Gasket"). Since I'm now going to a 427 or 434" small block with more HP, and since the car is apart I'm now considering 3" exhaust, with Magnaflows. I was curious about the crossmember, whether it had to be changed or if just "expanded" a little.
Thread Starter
Safety Car
Joined: Oct 2004
Posts: 3,923
Likes: 733
From: Youngstown Ohio
Team Owner
Joined: Apr 1999
Posts: 21,953
Likes: 1,445
From: Reno Nevada
2024 C3 of the Year Finalist- Modified
The bored out 427 small blocks are only $100 more and the extra 7 ci is worth about 10 extra foot pounds of TQ.
You are better off with a custom cross member. the stock exaust holes are to close to the tranny and heat is the enemy.
You are better off with a custom cross member. the stock exaust holes are to close to the tranny and heat is the enemy.
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