well guys it looks like this throttlebody that came with the FIRST is giving me too many problems..... so im getting made a conversion plate to use the stock 48mm throttlebody onto the first... i never like the design of the FIRST throttlebody, there arent many vac lines on it, the iac is under the plenum making it near impossible to reset the iac without removing the throttlebody, the lame tps bracket design and mount.... for whatever reason i cannot get this TB to act right... the stock gm one never gave me problems so i will just use that with an airfoil..... i will post pics of the conversion soon...

 

Don is doing the same thing. not sure how far along he is on the progress but im sure he can be helpful

 

What type if problems are you having ?

 

If your going thru the trouble to make an adapter etc. why not convert to a LSx style since its similar to the round mono-blade of the first also?

 

I brought this up as well in a different thread. There is a lot more work involved due to the LSx TB's having the cable on the passenger side, and there is no provision for TV cables.


In to see the finished product

 

Signing up.

 

i tried the ls1 route but like previously mentioned before its alot more involved with the first intake... so the adapter plate will convert any tpi, lt1 throttlebody to adapt to the first intake system... i just like the GM's design much better and it never gave me problems.... i will be using a 48mm throttlebody with an airfoil... im going to have the throttlebody shipped off for a complete rebuild... im almost willing to bet that it will perform alot better... The throttlebody never was the restriction of the LTR tpi setup...

 

plus this will also make the first look alot more like the factory unit... the throttlebody of the FIRST is vastly different and was the huge giveaway that something "was up" with this intake...

 

the problem is that the throttlebody is sticking a little bit and i tried three different types of throttlebodies and they all do the same thing... im guessing its a design flaw but for whatever reason i cannot get it to act right, plus as mentioned before i dont like the iac port under the plenum and the flunky tps mount design and just the arm linkage setup.... i never had sooo many problems with a throttlebody before so why not convert to a throttlebody i never had problems with...

 

Are you sure something didn't happen to your throttle cable? Is the spring causing it to catch??? I never had a minutes problem out of the T/B or TPS on the FIRST. The IAC is a pain, but I added in a 4-wire weather pac connector so I could easily disconnect the wiring harness as opposed to disconnecting it at the t/b - I think it was $12 at NAPA.

I do like the idea of adapting the dual t/b to make it look more stock. I had measured the plenums and it looks like you could cut off the mount for the FIRST and from a stock plenum and it would weld on to the FIRST without too much trouble.

 

"I do like the idea of adapting the dual t/b to make it look more stock. I had measured the plenums and it looks like you could cut off the mount for the FIRST and from a stock plenum and it would weld on to the FIRST without too much trouble."

...or get some 1/2 to 3/4" thick aluminum stock and make your own plate by welding it on to the First plenum. You may or may not want to cut off a little of the First plenum before welding on the bar stock. Really not that hard to do.

Edit: Look on page 5 post 245 of this thread. https://www.thirdgen.org/forums/tpi/...-runner-5.html

It shows an extension plate I made for the plenum. It could have easily been used for what you want to do. It is 3/4" thick. It is for a monoblade but could have two holes 58mm in diameter for example. The through holes could easily be 8mmx1.25 threads.

 

88fastgta,
i just watched you TB sticking video on you tube. Thats odd for it to be sticking to that extent.
This is a new one sent from FIRST?
My rpm hangs, but not like that, mine may be more of an issue with a sticky IAC unit.

I run no return spring, and it closes against stop with no issues, I suppose in my case the small spring on the other side, along with TV cable supply enought return force .
Have you checked for the washer in between the bracket and bracket mounting boss? There should be one that works as a spacer so the bracket does not bind against the mounting surface.
Worth a look.

 

I noticed that the spring is hooked up different than mine. Maybe u should try moving it. I tried to post a pic off my phone but can't. If someone pm's me i'll send them a pic. So u could post it

 

Got it figured out.

 

Yep,, I had my t/b spring attached just like 1rolmos. I looked at the "Official FIRST Thread",,,, I know that's how FIRST shipped it,,, but I'd suspect how you have your spring mounted is "the problem".

 

sorry guys for getting back soooo late....hmmmmm.... i have never tried that position... so i will try that out.... put gbayfisher yes the washer is there and everything i dont whats going on... all my cables easily reach and have no bind in them.... but i will try the position like the guy posted and see what happens from there..

 

one problem though i have my throttle cable hooked up to where 1rolmos spring is at.... idk guys i just really dont like the throttle body design..nothing against FIRST performance or anything.. i know its not the spring because it binds with the throttlebody off the car and with everything else not attached to it..... i have done numerous tests to rule out my cables, iac and the spring itself... i just want the stock throttlebody on there... this is too much work to get something sooooo simple to work right... i never thought once about my stock tb and thats how it should be....

 

I agree, the FIRST throttlebody leaves alot to be disired. I have yet to run my FIRST intake system, but the TB definitely stuck out as something that seemed underbuilt to say the least (IMO). The linkage seems sloppy(I added a nylon washer to take some of the side-side slop out) and the TPS mounting seems like an after-thought(?)

 

What about modding a stock plenum to work with the FIRST runners?

 

hmmmmm... i never thought of that....but the FIRST's plenum is alot better and overall bigger and longer and doesnt have all the restrictions like the gm plenum has........ would be cool though.... then it would really look stock...

 

It could be done but it would take a lot of work. Make that a lot of work. The easiest route is welding an adaptor plate to the front of the First plenum in order to accept a factory style throttle body.

 

update guys... i should have it done before the end of the month.... i just bought a 48mm throttlebody that has been rebuilt and a nice custom plate.. i am going to semi polish the throttlebody when i get it also i want to cut off all the ports like the coolant passages etc and weld them up to give it a nice clean look... i think this throttlebody will look WAY better than the FIRST

 

I had a little issue with mine hanging too but it was due to a lock nut on the side being cranked down a little too tight. I backed it up a turn and now things are much happier. If i had seen you were looking for one earlier I had the old one off my vette which I think would have saved you the air foil.
I'll agree the FIRST throttlebody required a little too much rigging to get it to work but I think it's going to work well.

 

well i got my throttlebody yesterday... i started semi polishing it and i cut off the coolant passages near the iac to give it a nice clean look since im not going to let coolant flow through the throttlebody.... its looking ALOT better already than the FIRSTs TB.... i will post pics later this morning.... im also waiting for my custom plate to come in....

 

so my throttlebody went from this

 

to this (sorry pics taken from camera phone) has ALOT more shine to it in person....

 

im still waiting on my plate to go on top the of the throttlebody as well...

 

Here is what I was working on:

 

I see a lot of people want to get rid of the firsts TB... that's looking good dyno Don... which throttle are you trying to adapt... it looks like I have to drill and tap the Plenum to make a 3/8 port so my drivers Side valve cover can get vacuum all the time since there is no port on the firsts base like the stock base has...hopefully my project will be done by the end of this month..

 

You just need to notch the back of the throttlebody where that triangle hole is.
Put a 1/4" notch on each side into the bores to let vacuum into the IAC hole like the '89-92 is.

 

Here's a pic I came across. Looks pretty nice.
Scroll down for it. https://www.thirdgen.org/forums/powe...ngle-60mm.html

 

Thats a neat adapter

 

just a little update... got my custom plate today.... here are some pics.. (sorry for the lousy camera phone quality).. once i get my adapter plate i will most likely sell my FIRST throttlebody for anyone who is interested in it....

 

Did you ever get it mounted?

 

The throttlebody adapter is done... i will post pics soon... so now im able to use my stock throttlebody on my first Intake...
Sorry for the long delay I have been busy and buying a truck ...

 

Good news. Now get those pictures posted so that we can see how it is done.

 

Oh I will.. you guys are gonna like this...

 

as promised my adapter.....

 

more pics of the adapter plate

 

Very good. That will work. How about the cable bracket? I guess that will be easy enough to do.

 

thank you... the cable bracket is bolted onto the FIRST's plenum, so no modding on that..with this adapter mated to the stock throttlebody its about the same length as the FIRST's throttlebody, so no lengthening the cable are required... this is a simple bolt on now with this adapter plate...

 

Looks good.
If it was mine, I would round the edges off, or even follow the contour of the TB.

Looking forward to seeing it on, and i hope it solves your issue.

Never mind .... I guessl plate matches the size and shape of the intake plennum!

 

i will post pics hopefully this weekend installed on the car... i know this will fix my issues.... the stock TB never gave me problems..... i just never like how the throttle cable mounts, tps and iac how mounted on the FIRST... not to mention the whole FIRST TB just gave me sticky throttle issues

 

You should send those pictures to Ken at First and let him see how its done. It actually might help him sell more units if he had that adaptor in being able to use ones own throttle body. When I was thinking of doing it I was going to just weld the adaptor plate to the front on the plenum. However your way is better for most people.

 

I thought Ken fabbed this adapter plate?

 

actually 1989gtatransam.... ken was the person who designed it for me lol..... it took him a while because he said he was backed up on orders and had alot of work to do... i told him ok because i have a ford ranger that i daily drive so i told him no rush on the product..... when i got the adapter this is what he told me in the e -mail


" There is a lot of hand work involved with this as you will see when you receive it. It is very time consuming and I will not make another for anyone else after this for sure"

 

I don't know what the market is but Ken could have it cast up than a quick machining would finish it off. The part is not that complicated.

 

Easily CNC'd

 

Ken would get alot more business if he had made these on the side for people like a 100 dollar add on price or something.... but i guess there are not enough people to make the adpater in production....i feel sorta special that ken has made me a custom peice just for me.. its definitely a piece of work.... i wonder if dyno don has finished his adapter plate

 

There is no doubt that Ken is a stand up guy that stands behind his product. He is willing to take my intake back if I can't get it to do what I want!
I only wish he had help to roll out new products sooner and quicker, ei; 2inch runner, siamesed runners, plates as in your case. I feel he should make this plate available.