Will the Holley 670 fit on the stock bore manifold? I'm considering getting one of these for the larger injectors and more easily adjustable regulator.

I was planning on gettting the Holley manifold or a carb manifold and an adapter plate. Now I was thinking if I can use it on the Edelbrock TBI, that may be the the better choice until I figure out if I'm going to swap in a 350, 383 or use vortec heads or whatever.

Just trying to get some info on this. I proabably won't do it til summertime. I need gears and posi long before I need the 670.

 

yes... but with all the turbulents and the contraction that will develop as the air goes from a large to a smaller bore, youd be better off just leaving it on the shelf untill you get the motor that you want. Itll probably flow less eficently then a stock tbi witht eh small bores on the stock manifold anbd the higher pph injectors will be too much for a 305.

 

I read somewhere that there is some sort of adapter that comes with it to smooth the transition from the big bore to the smaller bore. I need the fuel. My 305 is lean as hell after my mods. I was planning on getting the 305 version with the 57pph injectors.

 

have you messed with the fuel pressure, do you have a VAFPR? i have not heard of an adapter such as the one you speak of. you need a carb manifold....

 

I've made the stock regulator adjustable, but I never have been able to get it to raise the pressure any.

 

I found that the stock fuel pump has it's built in regulator set to around 15psi. If you have a strong spring in the regulator it's rare that the fuel will even make it into the return line! It's a POS fuel pump.
That adaptor that comes with the unit will work but it really should be avoided. It will however let you bolt it onto the smaller bore manifold, I just don't advise it. The injector pods are always swappable with 3 screws! So just bolt the holley (delco fuel injectors if newer than 3 years) injector pod onto the smaller bore TB.

 

Try to do something about your fuel pressure first. My mods are pretty close to yours, but I've been using the Holley 670 for a little less then a year. Mine has the the 57 pph delco fuel injectors. I'm still running rich even after some chip tuning and all the mods in my sig. And I just noticed one injector is spitting all over the place! Argh!! Try to get some chip tuning done first and see if that helps cure your fuel problem.

 

I've got the lt1 cam and the TPI heads with a 3 angle job, I don't think you do in your sig. If you do have a cam and you're still running rich maybe I will stay away from that til I get a bigger engine.

I may just need to upgrade my fuel pump to get more fuel or something. Thanks for the help guys. It sounds like with a 305 this TB may cause more problems than it will solve.

 

Keith, how do you know you are lean?


Don't bother with the larger TB unless you have the proper manifold setup.

 

Plugs and winaldl. I guess I really need to get into burning chips now.

I do need more fuel pressure though. I've never been able to get mine much high than stock.

EDIT: Actually what is most of the car's stock setting? I don't think mine even gets up to stock.

 

what is win aldl telling you to make you believe that youare lean and what do the plugs look like specifically


the reason im asking is because i spent probably a year thinking i was lean because everyone acts like a car is lean if its not performing like they think it should after mods. I'd hate for someone else to be going through the same things

Have you measured fuel pressure? Stock seems to vary i think its generally 10 -12 psi. The modded stock reg will max take it up to 14 or so if you are lucky

 

Plugs are white as snow. I've got a gauge on the fuel, it was at like 9 or 10 stock, I can't get it higher than 12 I think.

I think those numbers are right, I haven't messed with it much since late summer/early fall.

 

Vacuum Adjustable Regulator. What is the GM part number for that thing? I had forgoten about that thing until brodyscamaro said something about it.

 

are you checking the plugs from a WOT run?

btw, plugs and fuels these days show barely any color at all

thats another thing that had me thinking I was lean, everyone made it sound like a clean plug meant lean lean lean.

truth is, a plug from a wot run on a good afr on most cars looks like a brand new plug unless you really really know what to look for.