85 rx7 carb upgrade

mystery · 03-16-2013, 11:24 PM

Ive been told by numerous people in my area that I can save myself some headache swapping the carb out in my 85 rx7 and found one with the right specs but now I cant find an adapter plate to make it fit. Guy I spoke with told me he cant get em but this is a link to the carb I was lookn to swap.. guy thought I was nuts wantn to put a 600 cfm carb on a 1.1 ltr motor. http://www.jegs.com/i/Holley/510/0-1...ductId=1434023 my question is does anyone know where I can get this adapter plate??

t_g_farrell · 03-17-2013, 07:11 PM

Maybe try one of these? Not sure how it works with your budget.

http://www.racingbeat.com/RX7-1975-1...nts/16464.html

Tuning a 600 to work on a stock port 12A might be a challenge. Not sure what your setup
might be so can't really say if it will work easily.

mystery · 03-17-2013, 10:08 PM

Thats exactially what I was looking for but theres not just an adapter plate that can be mounted or does thw whole manifold have to be swapped?

FC Zach · 03-18-2013, 12:22 AM

Ive never seen such a thing for the Holley, there is an adapter that replace the upper assembly http://www.racingbeat.com/RX7-1975-1...ake/18100.html but these are for Dellorto/ Weber

diabolical1 · 03-18-2013, 06:02 PM

most I can say is that they existed at one point in time. I don't know about now and I can't recall who made/sold them, but they did exist. I had 2 friends back in the day with adapter plates to use Holleys on the stock 12A manifold, and I saw a handful of others on cars that I was less intimate with.

mystery · 03-19-2013, 06:55 PM

So only way for the holly to fit is by swapping out the entire manifold correct?

one320fc · 03-20-2013, 11:39 AM

As far as I know theses days you have to change out the manifold. Weber carbs are a great upgrade over stock but can be pretty expensive. You can find used Holley setups on the forums pretty cheap I picked up my intake for 120 bucks and spent 300 on a 465cfm carb from summit racing. My buddy had luck tunning a 600cfm on a stock port 12A also!

WE3RX7 · 03-20-2013, 04:28 PM

As long as the 600 is vac secondaries you can get it to work. Performance is minimal over the 400-450s though and I would shoot for the smaller carb if possible.

You will have to modify the throttle linkage and probably some slight grininding on the lower ear of the holley manifolds (older racing beat manifolds didn't fit perfectly and thats usually what you find for sale when buying used). All in all its not a big deal.

If this is a daily driver, I would NOT run the 600. If you can locate a weber or mikuni 40, I'd run one of those instead.

diabolical1 · 03-20-2013, 07:48 PM

Quote:

Originally Posted by WE3RX7

If this is a daily driver, I would NOT run the 600.

as a matter of fact, given your current situation, I would avoid it for now even if the car is not your daily driver. as mentioned before, it can be made to work, but you're skating uphill if you go this route, and if you think "making the Holley work" is going to be easier than just troubleshooting (or possibly) replacing the Nikki, then, oh boy, do you have another thing coming. not to mention you will probably cut your level of support on the boards by a good 60%, and of course, there is no FSM reference for it either.

I probably should have posted this in the other thread, but either way, i'd be telling you the same thing. if you want a Holley that's fine, but I think you need to get some basic troubleshooting and tuning skills under your belt first and it's much easier, and better to start with the Nikki.

mystery · 03-22-2013, 09:48 AM

Well problem im having is the guy before me had swapped out the carb that origiginally come on it with a used one he found somewhere. As well as redone alor of vaccuum lines that I cant find a diagram to how his setup of. The hood I have on the car has a diagram but it doesnt matchup to anything he has. Only thing thats the same is the hoses coming off the top of the row of relays.. theres no fuel in the carb bowls so im lost as where to start next. If it comes to me having to get another carb from what I hear edelbrock more or less will come tuned with minor adjustments holleys dont. Might be to the point I need to have it towed to a shop??

one320fc · 03-22-2013, 02:23 PM

Quote:

Originally Posted by mystery

Well problem im having is the guy before me had swapped out the carb that origiginally come on it with a used one he found somewhere. As well as redone alor of vaccuum lines that I cant find a diagram to how his setup of. The hood I have on the car has a diagram but it doesnt matchup to anything he has. Only thing thats the same is the hoses coming off the top of the row of relays.. theres no fuel in the carb bowls so im lost as where to start next. If it comes to me having to get another carb from what I hear edelbrock more or less will come tuned with minor adjustments holleys dont. Might be to the point I need to have it towed to a shop??

People might disagree with me on this one but if you don't have emissions where you live find the how to section and remove the crap and slap on a aftermarket carb! I just think you will invest way to much time tracking down crap that someone else has already screwed with! my 465cfm Holley pretty much fired right up out of the box..of course it did need to be tuned but will start and run. The archives and how to section will save you lots of headache! You can even find the factory service manual (FSM) for your 85..

mystery · 03-22-2013, 08:10 PM

Actually was able to talk to a mechanic today that used to own one and gave me some more than useful advise and offered to come take a look so that being said I should have an answer soon! And carb will get upgraded eventually my concern is just knowing it will run and stay running!

mystery · 03-31-2013, 08:37 PM

With lots of trouble shooting and tinking I dismantled my old carb and was able to find 2 more bolt filters after that I pulled them off my one in the car and found they where broken apart and clogging the primary jets from getting fuel... now that ive cleaned the gas tank its either going to get rebuilt or replaced. Been looking into the 48 ida weber with the new manifold as well. Anyone have any experience with them or know what else would need to be swapped after that?

03-16-2013, 11:24 PM	#1
mystery Rotary Fan in Training Join Date: Dec 2012 iTrader: (0) Posts: 91 Rep Power: 12	85 rx7 carb upgrade Ive been told by numerous people in my area that I can save myself some headache swapping the carb out in my 85 rx7 and found one with the right specs but now I cant find an adapter plate to make it fit. Guy I spoke with told me he cant get em but this is a link to the carb I was lookn to swap.. guy thought I was nuts wantn to put a 600 cfm carb on a 1.1 ltr motor. http://www.jegs.com/i/Holley/510/0-1...ductId=1434023 my question is does anyone know where I can get this adapter plate??

03-17-2013, 07:11 PM	#2
t_g_farrell Waffles - hmmm good Join Date: Aug 2008 Location: Huntersville, NC iTrader: (0) Posts: 757 Rep Power: 0	Maybe try one of these? Not sure how it works with your budget. http://www.racingbeat.com/RX7-1975-1...nts/16464.html Tuning a 600 to work on a stock port 12A might be a challenge. Not sure what your setup might be so can't really say if it will work easily. __________________ 1980 GS stockport, Fat Nikki, RB Dual Facetfuel pumps, Holley regulator, RB Street port exhaust, 2GDFIS, MR2 MK I electric fans, 2G strut bar, relayed fans, lights and fuel pump, LEDs Project Fat Nikki Budget 12A rebuild Video setup < $30.00

03-18-2013, 12:22 AM	#4
FC Zach RCC Loves Me Not You Join Date: Mar 2008 Location: Eagleville, TN iTrader: (2) Posts: 2,267 Rep Power: 19	Ive never seen such a thing for the Holley, there is an adapter that replace the upper assembly http://www.racingbeat.com/RX7-1975-1...ake/18100.html but these are for Dellorto/ Weber __________________ 1993 Yamaha GTS1000 1992 Celica Turbo AllTrac 1987 RX7 Sport 1979 Yamaha G1, KM24 powered 1975 Dolmar KMS4

03-20-2013, 11:39 AM	#7
one320fc one Apex @ a time Join Date: Feb 2008 Location: Culpeper VA iTrader: (1) Posts: 272 Rep Power: 17	As far as I know theses days you have to change out the manifold. Weber carbs are a great upgrade over stock but can be pretty expensive. You can find used Holley setups on the forums pretty cheap I picked up my intake for 120 bucks and spent 300 on a 465cfm carb from summit racing. My buddy had luck tunning a 600cfm on a stock port 12A also! __________________ 1983 Limited Edition SOLD 1977 Mazda REPU I will work on it one day I sware!! 1987 T2 um after the repu is done?? 2013 Chrysler 200 DD 2009 Dodge Journey 94 Volvo 850 N/A The slowest car I have EVER owned!!!

03-17-2013, 10:08 PM	#3
mystery Rotary Fan in Training Join Date: Dec 2012 iTrader: (0) Posts: 91 Rep Power: 12	Thats exactially what I was looking for but theres not just an adapter plate that can be mounted or does thw whole manifold have to be swapped?

03-19-2013, 06:55 PM	#6
mystery Rotary Fan in Training Join Date: Dec 2012 iTrader: (0) Posts: 91 Rep Power: 12	So only way for the holly to fit is by swapping out the entire manifold correct?

03-20-2013, 04:28 PM	#8
WE3RX7 RCC Addict Join Date: Feb 2008 Location: VA iTrader: (1) Posts: 1,812 Rep Power: 18	As long as the 600 is vac secondaries you can get it to work. Performance is minimal over the 400-450s though and I would shoot for the smaller carb if possible. You will have to modify the throttle linkage and probably some slight grininding on the lower ear of the holley manifolds (older racing beat manifolds didn't fit perfectly and thats usually what you find for sale when buying used). All in all its not a big deal. If this is a daily driver, I would NOT run the 600. If you can locate a weber or mikuni 40, I'd run one of those instead.

03-22-2013, 09:48 AM	#10
mystery Rotary Fan in Training Join Date: Dec 2012 iTrader: (0) Posts: 91 Rep Power: 12	Well problem im having is the guy before me had swapped out the carb that origiginally come on it with a used one he found somewhere. As well as redone alor of vaccuum lines that I cant find a diagram to how his setup of. The hood I have on the car has a diagram but it doesnt matchup to anything he has. Only thing thats the same is the hoses coming off the top of the row of relays.. theres no fuel in the carb bowls so im lost as where to start next. If it comes to me having to get another carb from what I hear edelbrock more or less will come tuned with minor adjustments holleys dont. Might be to the point I need to have it towed to a shop??

03-22-2013, 08:10 PM	#12
mystery Rotary Fan in Training Join Date: Dec 2012 iTrader: (0) Posts: 91 Rep Power: 12	Actually was able to talk to a mechanic today that used to own one and gave me some more than useful advise and offered to come take a look so that being said I should have an answer soon! And carb will get upgraded eventually my concern is just knowing it will run and stay running!

03-31-2013, 08:37 PM	#13
mystery Rotary Fan in Training Join Date: Dec 2012 iTrader: (0) Posts: 91 Rep Power: 12	With lots of trouble shooting and tinking I dismantled my old carb and was able to find 2 more bolt filters after that I pulled them off my one in the car and found they where broken apart and clogging the primary jets from getting fuel... now that ive cleaned the gas tank its either going to get rebuilt or replaced. Been looking into the 48 ida weber with the new manifold as well. Anyone have any experience with them or know what else would need to be swapped after that?