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darrellwalker Darrell Walker
Vancouver, WA, USA   USA
1966 Triumph TR4A "Christy"
1981 Triumph TR8 "Kate"
In reply to # 1533475 by gozto11 So I’m planning on dropping a Rover engine in a 7 over the next month. I see lots of posts about Holley 390. Which one? Is there one that’s better suited than others?

This is the one I think most people use:

https://www.holley.com/products/fuel_systems/carburetors/classic_holley/parts/0-8007



Darrell Walker
66 TR4A IRS-SC CTC67956L
81 TR8 SATPZ458XBA406206
Vancouver, WA, USA

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Darth V8R Avatar
Darth V8R Vance Navarrette
Beaverton, OR, USA   USA
1980 Triumph TR8 "Wedgie"
In reply to # 1533475 by gozto11 So I’m planning on dropping a Rover engine in a 7 over the next month. I see lots of posts about Holley 390. Which one? Is there one that’s better suited than others?

Also, I have 2 Old/Buick intakes. One of em has a quadrajet carb on it. Can I use that set up assuming I rebuild the carb? What mods to the intake will need to be done?

Oh one other thing...

I’ve read that the tr8 had thicker subframe spacers thus dropping the engine a smidge. If I go with the Buick/Olds intake, will it do the same as far as bonnet clearance. I guess the early intakes may’ve been shorter?

Regards

Todd

Todd:

My understanding is that the Holley 390 is no longer available new, and in any event it flows slightly less than the original Zenith carbs. Personally I do not understand why people bother, unless it is for simplicity's sake - but a modern manifold may make up for the flow deficiency. The Quadrajet is too large, being a 750 CFM design, and it certainly is no simpler than the Zeniths as it has metering rods (aka needles) and, in some cases at least, a remote choke that must be mounted on the manifold. Since the Quadrajet was never offered on the 215, it must be a conversion so you need to check that the choke is handled properly if you decide to use it. Neither the original nor the Edelbrock manifolds have provisions for a remote choke. Fabricating a mount for one is not difficult, however. You may find that part throttle drivability is poor with a carburetor that large.

The Edelbrock 500 seems like a better choice to me (full disclosure, I have never done a 4BBL conversion, I am running modified Zeniths). While the original manifolds were decent for their day, the modern design of the Edelbrock gives it a definite edge. The earlier manifolds will give you more clearance, being a lower profile design. But the same thing that makes the Edelbrock taller makes it deliver better performance, namely that the runners are aimed straight at the intake ports, as opposed to the older designs where the entrance into the intake port was more of a dog leg.

The thicker spacers for the TR8 sub frame don't just give you more hood clearance, they reduce front end dive during braking. So they are also desirable from a handling standpoint. You can install an anti-dive kit instead of using the spacers.

I assume your donor engine is injected. Any reason you want to dispense with the injection and go with a carb?

Vance



1980 Platinum Metallic TR8, navy blue interior
Bare metal respray, Crower cam, raised compression
ported heads, modified Zenith carbs, 0.060" overbore

gozto11 Avatar
gozto11 Todd Bermudez
Cincinnati, OH, USA   USA
Hi Vance, great info...

The engine didn’t come with an intake or carb(s). I do have an original intake/carbs in addition to the 2 4bbl intakes.

So I’ll order the anti-dive kit. Do I need the taller spacers too? Along w longer subframe bolts and spacer tubes? I’m doing this swap as a surprise for my son. He’s away doing Navy training stuff

Oh I also forgot about to ask about exhaust. I have a used TR8 system but I’ve no manifolds. What are folks doing about manifolds?

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darrellwalker Darrell Walker
Vancouver, WA, USA   USA
1966 Triumph TR4A "Christy"
1981 Triumph TR8 "Kate"
In reply to # 1533532 by gozto11
So I’ll order the anti-dive kit. Do I need the taller spacers too? Along w longer subframe bolts and spacer tubes? I’m doing this swap as a surprise for my son. He’s away doing Navy training stuff

Oh I also forgot about to ask about exhaust. I have a used TR8 system but I’ve no manifolds. What are folks doing about manifolds?

I would advise lowering the sub-frame, clearance for the air cleaner is already tight if you have them.

You can either go to headers, or probably find used exhaust manifolds.

The link I provided shows that the Holley 390 is still available. The Edelbrock that Vance mentions has the advantage (I think) that you don't have to drain the float bowls to change jets. I suggest the you budget a wide-band O2 sensor and a vacuum gauge (both can be temporary) to get the carb dialed in.



Darrell Walker
66 TR4A IRS-SC CTC67956L
81 TR8 SATPZ458XBA406206
Vancouver, WA, USA



Edited 1 time(s). Last edit at 2018-05-16 10:53 AM by darrellwalker.

Darth V8R Avatar
Darth V8R Vance Navarrette
Beaverton, OR, USA   USA
1980 Triumph TR8 "Wedgie"
In reply to # 1533541 by darrellwalker
The link I provided shows that the Holley 390 is still available. The Edelbrock that Vance mentions has the advantage (I think) that you don't have to drain the float bowls to change jets. I suggest the you budget a wide-band O2 sensor and a vacuum gauge (both can be temporary) to get the carb dialed in.

Darrell:

Interesting. Woody at the wedge shop stopped offering them new, and now only offers the 600 CFM. I had read on his site that he was no longer able to obtain them new, so he was using the larger model. Well, it would not be the first time I read something on the internet that was absolutely not true. eye popping smiley

OK, so the supplier you showed is able to get them, terrific. I stand corrected.

And you are correct, the Edelbrock does not require draining the fuel to alter the mixture, and because it is split horizontally above the fuel level, it won't ever leak. It would be my first choice for those reasons and the fact that it offers a step up in flow without being too large. Of course, now that my credibility has been shredded on the Holley 390, you may wish to disregard everything I just said. spinning smiley sticking its tongue out

I have had good results using plug cuts to set the mixture, but of course an O2 sensor is the ultimate in tuning tools. It's just that I am sooo cheap!

Vance



1980 Platinum Metallic TR8, navy blue interior
Bare metal respray, Crower cam, raised compression
ported heads, modified Zenith carbs, 0.060" overbore

Bergie Bob Berg
Powell, OH, USA   USA
I would skip the holley 390 (8007) and look at this carb(quick fuel 570- vac sec/electric choke) ...more tunable than the holley(air bleeds and IFR) and less expensive...no mater what carb you choose you will need to make some adjustments to it based on your engine and setup...

https://www.summitracing.com/parts/qft-br-67253/overview/

POW Peter Wirth
HEBRON, NH - New Hampshire, USA   USA
And there is this thing too: https://www.jegs.com/i/Quick-Fuel/793/SL-450-VS/10002/-1?CAWELAID=230006180002559530&CAGPSPN=pla&CAAGID=44693592161&CATCI=aud-224375369591:pla-193096599911&CATARGETID=230006180039219763&cadevice=c&gclid=EAIaIQobChMItfeHgqSL2wIVFFqGCh1FggO7EAQYBSABEgL5KfD_BwE

I've gone through a Holley 600. Could not tune out a flat spot no matter what I tried. The best I could do was adequate if I only eased into it and it always felt lazy. It's too big for a stock 3.5 and that equals low air speed through the ventures and inherent bog. Next came an Edlebrock 500. It was much better and is very tunable and although I managed to get the 'between shifts' bog out of it, no matter what combo of practical combinations of Edelbrock jets and metering needles I tried, I could not get a herky-jerky low speed, light load surge out of it. Plus it too felt lazy. I think it's too big too. As far as ease of needle and jet change, it's true the Edelbrock carb can be left in place and just the top of the carb removed for changes but IMHO It's easier to remove the Holley and open it up on the bench than to fiddle-fart around with all the screws and linkage clips to get the Eddy apart. The Holley 390 I have now is absolutely spectacular - finally. The car has instant 'snap' everywhere and overall drivabiliy is excellent. This was not out of the box however. There is a myriad of accelerator pump cam choices, accelerator pump squirters, powervalves, primary and secondary jets, and last but not least secondary springs that control vacuum actuation of the secondaries. Sorry about the annoying caps now, but anyone who claims "OUR CARB KITS ARE PRE JETTED AND SET UP FOR YOUR ROVER ENGINE" are lying to you. Unless you are willing to settle for mediocrity, be prepared to do some homework, spend some money on little carb parts and learn.
Honestly, what i would do is concentrate on the Strombergs. They are fine carbs, they would be indeed pre set-up for the engine (assuming it is not radically modified) and are relatively simple to clean and rebuild. I honestly think this would be the best route to follow that would allow your son to enjoy the car after his deployment without having to fart around with tuning the unknown. - Pete

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bowen6951 Avatar
bowen6951 Gold Member rob bowen
Fontana, CA, USA   USA
Hi Todd,
I purchased a '92 3.9 for my car and the exhaust manifolds that came with it are pretty nice looking pieces. If I ever get the State to let me change to a later style F.I. I will use those manifolds as I know headers would be a No-No. Thanks, Rob

Darth V8R Avatar
Darth V8R Vance Navarrette
Beaverton, OR, USA   USA
1980 Triumph TR8 "Wedgie"
In reply to # 1533656 by POW Honestly, what i would do is concentrate on the Strombergs. They are fine carbs, they would be indeed pre set-up for the engine (assuming it is not radically modified) and are relatively simple to clean and rebuild. I honestly think this would be the best route to follow that would allow your son to enjoy the car after his deployment without having to fart around with tuning the unknown. - Pete

Wow Pete. Sounds like the voice of experience.

I must say I am very happy with the Zeniths. They work well, and despite a few sulfurous comments about the water chokes they do exactly what they are supposed to do. I did change my needles after modifying the engine, but then I knew that would be needed.

I already take heat for it not being a 'real' classic British car. If I put a 4BBL on it, the local LBC club would probably go apoplectic.

Went on a great little road rally last weekend sponsored by the local British Garage. Great fun. But I was the only wedge in attendance. sad smiley

Vance



1980 Platinum Metallic TR8, navy blue interior
Bare metal respray, Crower cam, raised compression
ported heads, modified Zenith carbs, 0.060" overbore

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POW Peter Wirth
HEBRON, NH - New Hampshire, USA   USA
In reply to # 1533663 by Darth V8R
I already take heat for it not being a 'real' classic British car. If I put a 4BBL on it, the local LBC club would probably go apoplectic.

Went on a great little road rally last weekend sponsored by the local British Garage. Great fun. But I was the only wedge in attendance. sad smiley

Vance

Went on a rally put on by our local club too this past weekend. Also the only Wedge in attendance. The route incorporated 3 laps of a new private club track ($$$ to belong, not me) and I had the good fortune (I was pushy) of getting in line 2nd behind the pace car, fallowing some kind of Jag XK F. The 8 did well. Easily kept pace with the track car and the Jag. (but I'm an excellent driver - Raymond Babbitt). The Jag sounded great with some kind of aftermarket exhaust, I think, and the computer generated "BRAAAP" between downshifts of the DCGB were superb. I just stuck the 8 in 3rd and hung on his tail. Great fun! - Pete

lgray001 Avatar
lgray001 Gold Member Larry Gray
Lexington, VA, USA   USA
1976 Triumph TR7 "POS-2"
1979 Triumph TR7 "The Money Pit"
I've got a TR7, but I'm curious, has anyone used the new Holly 4-barrel EFI units available?


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darrellwalker Darrell Walker
Vancouver, WA, USA   USA
1966 Triumph TR4A "Christy"
1981 Triumph TR8 "Kate"
In reply to # 1534309 by lgray001 I've got a TR7, but I'm curious, has anyone used the new Holly 4-barrel EFI units available?

Not the Holley, but I have a FiTech TBI on my TR8. I've been very happy with it.



Darrell Walker
66 TR4A IRS-SC CTC67956L
81 TR8 SATPZ458XBA406206
Vancouver, WA, USA

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