Here's my set up
383ci, brodix ik180cc heads, cam-252/266, 208/217, .477/.472(w/ 1.6 RR), 113 lobe, 9.77-1 CR, 1 5/8" hooker shorty headers.
What I'm gonna order-TPIS runners, TPIS baseplate, plenum porting by corvetteplenum.com Should I go with a 52mm or 58mm TB? Will 24lb injectors be adequate? this will primarily be a fun street car.
I was in my last year of college when I built the engine, didn't want to spend anymore money on the car at that time so I just put the stock TPI back on so it would run, now it's time to upgrade.
Thanks
383ci, brodix ik180cc heads, cam-252/266, 208/217, .477/.472(w/ 1.6 RR), 113 lobe, 9.77-1 CR, 1 5/8" hooker shorty headers.
What I'm gonna order-TPIS runners, TPIS baseplate, plenum porting by corvetteplenum.com Should I go with a 52mm or 58mm TB? Will 24lb injectors be adequate? this will primarily be a fun street car.
I was in my last year of college when I built the engine, didn't want to spend anymore money on the car at that time so I just put the stock TPI back on so it would run, now it's time to upgrade.
Thanks
52 will feed it. 24's will be enough injector. thats a mild cam to be putting in a 383, it wont need much airflow
Senior Member
Thats close to my setup, get the AFPR you may need to bump the fuel pressure a bit. Put a vacuum gauge on the plenum, if it has any vacuum at wot go bigger. Remember to update your air cleaner and duct work.
The maf grs/sec limit "max air flow vs rpm" table will need to be raised. Not changing this, will limit your motor to 350 air flow and power. It will make a big lean spot at peak VE. My motor hits this table at 1800 rpm and rides it to the 255 limit. At 2500 rpm injectors cut back and power starts to drop.
This is with a stock unported TPI.
The maf grs/sec limit "max air flow vs rpm" table will need to be raised. Not changing this, will limit your motor to 350 air flow and power. It will make a big lean spot at peak VE. My motor hits this table at 1800 rpm and rides it to the 255 limit. At 2500 rpm injectors cut back and power starts to drop.
This is with a stock unported TPI.
Supreme Member
Heck, thats a baby cam for a 383. A hair above stock. In all honesty you could get away with the stock 48MM TB
Supreme Member
All true. However if you decide to step up the mods a 58mm will not hurt a thing if you are going to buy a throttle body. I believe the price is the same. That way you only have to buy it once.
Supreme Member
58 is rediculous. Thats uber big. 52 IMO is gonna be great unless you get bigger intake. IE HSR
Senior Member
Quote:
Originally Posted by Mkos1980
Heck, thats a baby cam for a 383. A hair above stock. In all honesty you could get away with the stock 48MM TB And those LPE 216 and 219 are what daddy cams?
those are kinda toddler, not baby 

Senior Member
a 52mm flows 900cfm and the 58 flows 1100. I see a lot of people on this board that have a 58 and make less than 400hp. Kind of funny that they dont need it, I only run a 52 and works great!
I had vacuum at WOT on my 383.
I'm still waiting for my new 58mm to show up in the mail.
If you must step up, step up to the 58. Why limit yourself later.
I'm still waiting for my new 58mm to show up in the mail.
If you must step up, step up to the 58. Why limit yourself later.
Senior Member
Quote:
I'm still waiting for my new 58mm to show up in the mail.
If you must step up, step up to the 58. Why limit yourself later.
Originally Posted by Viprklr
I had vacuum at WOT on my 383.I'm still waiting for my new 58mm to show up in the mail.
If you must step up, step up to the 58. Why limit yourself later.
Are you going to check for vacuum after you install the 58mm??
Senior Member
Quote:
Originally Posted by 1989GTATransAm
All true. However if you decide to step up the mods a 58mm will not hurt a thing if you are going to buy a throttle body. I believe the price is the same. That way you only have to buy it once. ht4100
"this will primarily be a fun street car."
With the auto (stock stall?) and 3.23 gears, a 58mm will be abit touchy at cruise speeds. If it was me, I would wait for more mods, then when the need shows, upgrade the TB to what ever seems to work.
If he wants to run that 383 setup for awhile, then a 52 is a much better choice. Hell i would run the 48mm stocker
So it seems that a 52mm would be the best for what I want to run. My stock one is worn out anyways, so I might as well upgrade. I have a carb spring rigged up to prevent random accleration right now.
It looks like my cam is a little tame then, it's RPM range is 1100-5100 with a 383 which is what I thought would be good for a TPI. I'm not opposed to changing the cam, but it is a flat-tappet style. Any suggestions? I still want to run a modified TPI system
Pandin-My car has a stock stall with 3.23 gears, and tranny cooler. I have a bigger Walbro already installed, and a AFPR, but it's not installed yet. You said you had a similar set-up, what does yours consist of?
It looks like my cam is a little tame then, it's RPM range is 1100-5100 with a 383 which is what I thought would be good for a TPI. I'm not opposed to changing the cam, but it is a flat-tappet style. Any suggestions? I still want to run a modified TPI system
Pandin-My car has a stock stall with 3.23 gears, and tranny cooler. I have a bigger Walbro already installed, and a AFPR, but it's not installed yet. You said you had a similar set-up, what does yours consist of?
Quote:
Yes. It should be here on Tuesday. I figure that by the end of Sunday i'll have a chance to hit WOT. I just need to pull the car out of bed.Originally Posted by pandin
Are you going to check for vacuum after you install the 58mm?? that cam has similar specs to stock L98 cams which peak at 4400 rpms in a 350. on a 383 with modded TPI, i dont think you'll see much more than 4200 rpms
Modded TPI can feed that 383 up to near 5000 rpms. you can use a cam alittle larger than the one you have. most of those operating ranges given with cams are alittle higher than what the cam will actually do, BUT some alittle lower. They usually give where power starts coming on and where power starts falling off badly. I like to select a cam that shows a power band just a tad higher than what you think the intake will support. Stock L98 cam may peak at 4400-4500 with stock TPI, but when i put on my stealth ram intake, it peaked at 5000-5100 rpms. So the cam range drastically depends on the intake (and heads) you run, but i still like to go alittle higher than the intake is rated at to get the most power out of the setup.
you got decent heads and upgraded TPI, i wouldnt hesitate to run something like a 218/224 or 224/230 cam for that 383 and TPI. Still be a nice street driveable car with cams like that. Comp cams would be xe262 or 268. the 268 is a nice choice overall for alot of cars. With the larger cam tho you should look into a torque converter with abit more stall speed. Will really make the car a pleasure to drive
Modded TPI can feed that 383 up to near 5000 rpms. you can use a cam alittle larger than the one you have. most of those operating ranges given with cams are alittle higher than what the cam will actually do, BUT some alittle lower. They usually give where power starts coming on and where power starts falling off badly. I like to select a cam that shows a power band just a tad higher than what you think the intake will support. Stock L98 cam may peak at 4400-4500 with stock TPI, but when i put on my stealth ram intake, it peaked at 5000-5100 rpms. So the cam range drastically depends on the intake (and heads) you run, but i still like to go alittle higher than the intake is rated at to get the most power out of the setup.
you got decent heads and upgraded TPI, i wouldnt hesitate to run something like a 218/224 or 224/230 cam for that 383 and TPI. Still be a nice street driveable car with cams like that. Comp cams would be xe262 or 268. the 268 is a nice choice overall for alot of cars. With the larger cam tho you should look into a torque converter with abit more stall speed. Will really make the car a pleasure to drive

Senior Member
Stock MAF TPI, 383, 24# FMS (m9593-a302), AFPR (50#), Edelbrock performer heads, comp XR 258 HR 10 (12-408-8), stock exhaust-no cat, 3.07 Dana 36 posi, 700R4, 2000 stall, 255-50-16, stock bua chip.
This is my DD (rain or snow). It is set up for 1000-5000 rpm and does quite well. It could use a tune (ordered a prominator) also need a WB.
This car lives at 3000 rpm and down. Has a nice wheel spin/chirp 1 and 2 and is all the car/driver wants. 1 Year lic suspensions start at 80 mph in this county and the car can do that coming out of 2nd. Does 125 mph in third at 5000. BTW gets 15 mpg to work and 20 mpg trip. 55 mph = 1550 rpm @ 12HP.
This is one of 7 corvettes, 1 Harley, 1 Indian, and a 2000 LS1 pu.
This is my DD (rain or snow). It is set up for 1000-5000 rpm and does quite well. It could use a tune (ordered a prominator) also need a WB.
This car lives at 3000 rpm and down. Has a nice wheel spin/chirp 1 and 2 and is all the car/driver wants. 1 Year lic suspensions start at 80 mph in this county and the car can do that coming out of 2nd. Does 125 mph in third at 5000. BTW gets 15 mpg to work and 20 mpg trip. 55 mph = 1550 rpm @ 12HP.
This is one of 7 corvettes, 1 Harley, 1 Indian, and a 2000 LS1 pu.
Senior Member
This will give some comparison not sure where these came from.
Cam info with peak hp and torque numbers:
-Comp 12-408-8(206/212 @.050).....416hp @ 5000 rpms, 483 ft lbs @ 3800 rpms.
-Comp 12-423-8(224/230).....462hp @ 5500 rpms, 486 ft lbs @ 4100 rpms.
-Comp 12-443-8(242/248).....509hp @ 6100 rpms, 508 ft lbs @ 4500 rpms.
-Comp 3311SHR110 (206/206).....442hp @ 5300 rpms, 495 ft lbs @ 3700 rpms.
-Comp 33145SHR110 (224/224).....454hp @ 5500 rpms, 488 ft lbs @ 4000 rpms.
-Comp 3317SHR110 (242/242).....498hp @ 6000 rpms, 497 ft lbs @ 4500 rpms.
All cams had a LSA of 110.
Here is the credits:
If you don't have Chevy High Performance mag...I will post some results I thought were interesting.
Here is the setup:
383, 11.5 compression
TFS 190cc heads
1 3/4" long tubes
Edelbrock Air Gap dual plane manifold
750-cfm carb
91 octane
160 degree H20 temp
Max timing-34*
Cam info with peak hp and torque numbers:
-Comp 12-408-8(206/212 @.050).....416hp @ 5000 rpms, 483 ft lbs @ 3800 rpms.
-Comp 12-423-8(224/230).....462hp @ 5500 rpms, 486 ft lbs @ 4100 rpms.
-Comp 12-443-8(242/248).....509hp @ 6100 rpms, 508 ft lbs @ 4500 rpms.
-Comp 3311SHR110 (206/206).....442hp @ 5300 rpms, 495 ft lbs @ 3700 rpms.
-Comp 33145SHR110 (224/224).....454hp @ 5500 rpms, 488 ft lbs @ 4000 rpms.
-Comp 3317SHR110 (242/242).....498hp @ 6000 rpms, 497 ft lbs @ 4500 rpms.
All cams had a LSA of 110.
Here is the credits:
If you don't have Chevy High Performance mag...I will post some results I thought were interesting.
Here is the setup:
383, 11.5 compression
TFS 190cc heads
1 3/4" long tubes
Edelbrock Air Gap dual plane manifold
750-cfm carb
91 octane
160 degree H20 temp
Max timing-34*



