I have a question, if I may be so bold?

Does the intake on the 89 to 92 TPI have a hole behind the left runner where the 9th injector was on MAF systems?

In other words, if I were to use a 87 runner on a 92 would I have an opening in the intake where the 9th injector went?

The reason for the question is the TPI setup I have is from a 87 Vette originally and their runners are very textured. I polished the plenum and plan to polish the runners as well. But these will be LOTS of work to get smooth. I have a friend that has a 92 Camaro that has 180K on it and he is in need of injectors. He offered to trade runners with me.

Thanks in advance for your help.

 

Anyone? Thanks

 

No, 89 MAF and 90-92 SD systems didn't have the cold start injector hole. If you want to use an earlier style runner you'll need to find a way to plug it.

 

Thank you sir!

 

When you say intake... you mean lower or the plenum? The lower still has a spot. The plenum does not.

 

Sorry, I should made it more clear. Yes the lower. I want to put a set of runners from an 87 Vette on a 92 Camaro and the Vette runners have a hole for the 9th injector. I was wondering if there was going to a huge vacumn leak. I guess a cold start delete will be order?

 

Yes, the lower intake has a hole for it. The runners normally block that spot though. In this case, you will have to block off the runner.

 

Yeah, block the runner hole. Also be aware though that your friends 92 might have the same textured style runners. Vettes always got those runners, and at some point in 92 GM started using old vette stock runners on the f-bodies since vette was already using LT1, and there weren't anymore TPI cars coming out either. They also started using blank TPI top plates too (instead of the tuned port injection ones) like the LT1 and the Sy / Tys used.

Still, a lot of people like the textured runners, so you should have no problem finding someone to swap if your friends doesn't work out.

 

What are the advantages of Textured runners? I just did a search and only came up with 4 threads, one of which is this one. But none of them really say why textured is better. I did read a small bit about more surface area. But thats about it for that.

 

there is no advantage to the textured or cast runners. they just dont look like runners that were made durring the mid 80's to early 90's for camaros and birds. They have a ruff look to them.. there not as smooth.

 

Well, I got the switch done. BUT, there is one point that I didn't think of and no one else mentioned. Although this is a very rare switch, it's worth mentioning for others that the plenum on the 92 doesn't have the additional hole for the 9th injector plumbing. If you put runners from a 9th injector setup on a non-9th setup, you will have a massive vac. leak at the plenum. I was able to run down a 1/2 inch plug and completed the switch, but it was a surprise.