I'm trying to put together an engine for my 85 TA. It now has a 305 TPI. I am wanting to order a shortblock with the L31 vortec heads and putting a Comp 260AH-12 cam in.
Will the upper part of my TPI from the 305 work.
What size of injectors will I need to get, considering I would like to later add a 100-150 shot of NOS?
Also what is a good ignition to go with?
Will the upper part of my TPI from the 305 work.
What size of injectors will I need to get, considering I would like to later add a 100-150 shot of NOS?
Also what is a good ignition to go with?
Supreme Member
That's a terrible cam for TPI. Find a cam that's set up specifically for TPI, it needs it to do its best.
Yes the upper part will work. The intake base will not. You will ABSOLUTELY HAVE TO HAVE the correct one, which only exists from one supplier, and is $not cheap$. Here's a pic, posted in the last day or 2 by another member, and enhanced so you can see the problem.
Injector size would depend on the motor size.
Stock is fine.
Yes the upper part will work. The intake base will not. You will ABSOLUTELY HAVE TO HAVE the correct one, which only exists from one supplier, and is $not cheap$. Here's a pic, posted in the last day or 2 by another member, and enhanced so you can see the problem.
Injector size would depend on the motor size.
Stock is fine.
Yeah, I know I have to have the SDPC TPI Vortec baseplate.
The cam is actually part # CC12-314-4 at SDPC. It is supposed to be for TPI vehicles. Would 24lb injectors be enough for a 350.
The cam is actually part # CC12-314-4 at SDPC. It is supposed to be for TPI vehicles. Would 24lb injectors be enough for a 350.
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The upper part of your TPI will work, the base wont and not because of the guy aboves picture only, but rather the vortec manifolds are designed with only 8 bolts to hold it down in mind. Stock gm heads have 12 bolts and running just 8 might not get the best seal. Get the SDPC vortec TPI base.
If you run 24lb injectors, you better be good at tuning EPROMS. I did a similar thing to you: (350, heads/cam) instead of my 305 and put in 24lb injectors... and it ran good WOT but at idle/cruise I was so rich it washed my cylinders and my rings never seated.
I don't see why that guy says it's a horrible cam for TPI. It's dual pattern and a descent duration. 212/218 is kind of small however.
It does have good lift. You are getting the L31 heads which have the valve spring upgrade, that's good and all, but you may want to consider spending the $150 and have screw in studs installed. I ran a comp cam with less lift, and ended up pulling studs. NOT FUN.
I would recommend the CompXE262h-4 the 262/vortec build ups I've seen are easily capable of 400hp flywheel. 218/224, .464/4.70 lift, on a 114(MUCH more computer friendly and a broader powerband) . And you should be able to get away with running that lift on your heads w/o pulling studs... but alot of the time its the valve spring that ends up being the culpret in pulling the studs.
Injectors aren't going to play a part in the N2O like you think. You tap one of the n20 solenoids onto your schrader valve, which is how it gets it's fuel for the fuel only jet(s). What this means, is you need a fuel pump capable of keeping the pressure of your injectors as well as the n20 solenoid.
As for ignition... upgrade the coil, and be happy. Too many people, myself included, have put MSD boxes on and been unhappy. I'll tell you that even on a stock 305 TPI the MSD Gm coil mad the idle smooth and got a lil more milage.
If you run 24lb injectors, you better be good at tuning EPROMS. I did a similar thing to you: (350, heads/cam) instead of my 305 and put in 24lb injectors... and it ran good WOT but at idle/cruise I was so rich it washed my cylinders and my rings never seated.
I don't see why that guy says it's a horrible cam for TPI. It's dual pattern and a descent duration. 212/218 is kind of small however.
It does have good lift. You are getting the L31 heads which have the valve spring upgrade, that's good and all, but you may want to consider spending the $150 and have screw in studs installed. I ran a comp cam with less lift, and ended up pulling studs. NOT FUN.
I would recommend the CompXE262h-4 the 262/vortec build ups I've seen are easily capable of 400hp flywheel. 218/224, .464/4.70 lift, on a 114(MUCH more computer friendly and a broader powerband) . And you should be able to get away with running that lift on your heads w/o pulling studs... but alot of the time its the valve spring that ends up being the culpret in pulling the studs.
Injectors aren't going to play a part in the N2O like you think. You tap one of the n20 solenoids onto your schrader valve, which is how it gets it's fuel for the fuel only jet(s). What this means, is you need a fuel pump capable of keeping the pressure of your injectors as well as the n20 solenoid.
As for ignition... upgrade the coil, and be happy. Too many people, myself included, have put MSD boxes on and been unhappy. I'll tell you that even on a stock 305 TPI the MSD Gm coil mad the idle smooth and got a lil more milage.
I've been really busy lately and haven't had time to check the board. Thanks for all the help, input, suggestions.