dont all the TPI and LT1's open with the Top going forward and bottom going in?? the must have changed it for the LS1.. then went back to it for the LS2.. interesting..




i just went outside.. took off the air tube to my LT1 powered thirdgen... top of the blade opens forward.. because the cable is attached to the bottom of the arm and pulls back.. looks like these LS1's wrap over the top and pull back.. so why not just flip the design? it shouldnt be too hard to do..

 

All of the ls candy cane intakes have #2 entry in the 2 oclock position.
With stock cam shafts disribution through out the load range is pretty good.
The minute you put a larger cam in you really upset the dynamics of the intake. You will see up to two and sometimes almost three a/fs cyl to cyl
With large cams the a/f spread is still evident at wot through out the rpm range although to a much smaller degree. So to answer the question of which way is better for the throttle to open. I have driven both throttles on the same LS6 and can find no difference in engine smoothness which would indicate a distribution issue.

myron c

 

damn $550 for the UMI TB. That's a little pricey for my tastes.

 

We have never tested the UMI tb on a ls7. The ls7 is still a new engine to us, we have not tested many things yet, but we are trying! The pm you sent was interesting to look at, very nice looking part. It looks like the tb still has a valve that opens in on top? It would be interesting to test one, how fast can you get one to me?


Kurt

 

The ls7 intake has the #2 intake port at 12 o'clock position, it seems that they shortened the runners for some added high rpm power. This puts the port opening about 1.3 inches from the closed throttle blade. When it tips in on top it gets closer to ramming the air down cyl #2. On a ls6 style intake the port opening for #2 is to the side of the tb and would not suffer from the same problem.
I have only ran a cable drive on the dyno with it inverted to keep the problem from happening. The only ls7 we have had in a car was stock with the tb that opens in at the bottom. The UMI info on ls7's running well with there tb is promising.

Kurt

 

I guess the next question then,if the UMI unit works,is if the base where it mounts to the throttlebody is thicker? The throttle blade opens the same way as a NW or TPIS so what are the differences that would make it work versues the other respected units out there. I have a TPIS mounted to a LS7 intake right now. It's only a mock up per say, because I have yet to use it. But the clearances all seem to be good to go. The only problem here would be the A/F ratios and the stumble at part throttle like everyone is talking about. I would be interested to send my throttlebody to test it on a LS7 if there is someone out there with a LS7 thats interested in doing so Traver

 

I think the NW TB upside down withspacer is the cheaper way to go and if the only difference between the NW TB and the UMI is the cable then I would go NW and save $200.

 

Kurt,
PM me with a address and contact info. Better yet, email it to me.
mark@umiracing.com

Thanks,
Mark

 

Anyone ever put a fly-by-wire TB into an F-body? I am thinking the effort it would take wouldnt be worth it, but it might be cheaper than a 90mm cable TB that opens the wrong way.

 

Does anyone offer this kit?

 

What are you going to use for a PCM to control it? You'd have to retrofit the gas pedal from a vette too, and if you have it, traction control.

 

A ton too much hassle to do for no reason.

 

did anyone see in the oct GM Hightech there was a company call howell-efi.com was suppose to offer a kit?

 

Right. I wasnt sure how much work it was. Perhaps some simple wiring would take care of it, but then you need a Vette gas pedal and sensor to control it and the PCM has to be calibrated for it and what not. Perhaps there is a kit.

 

Part throttle matters. Unless you do some kind of racing, the engine spends like 97% of it's time at part throttle. You want everything to be balanced. You want maximum power all time given any condition.

 

I believe the 97 and up v6 fbody had an electric pedal which would fit perfect. So is there a kit to make it electric?

 

Myron, have you ever considered doing the same mod to an ls6 intake that you do with your oval TB, i.e. a 90MM GM TB on an Ls6.

We ran one of your oval TB ls6's at one point before going to a FAST. I would think a modified ls6 would be good for a whole bunch of folks since the ls2 intake is down on power compared to the LS6.

Anyway, the info I have came from Gm in their testing. I'm sure as soon as the motors get out there, we'll here if other folks can replicate the same issue.

 

I was informed that Nick Williams was working on a cable operated throttlebody to fit right on the LS7 intake with no issues.(including airflow) Does anyone out there know if this is true or not? Still trying to decide if I should sell my TPIS 90 mm that I have now and hope by spring time that someone comes up with a new design without any issues! Traver

 

Our 90MM will bolt on a LS7 intake. You seem to imply that you are having trouble with our 90MM. If you are give us a call and we will resolve any problem at no cost to you. Ask for me, if not here leave a number I'll call you.

Myron Cottrell.pres

952 448 6021

 

Just thought I should put a link to this here.

https://ls1tech.com/forums/showthrea...3&page=2&pp=20