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Wedge TR8 4 barrel conversion numbers

bluemiata90

Jedi Trainee
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I have a 1980 TR8 carburated and am considering converting it to a Holley 4 barrel. Does anyone know the intake and carb. numbers that are needed for this conversion and any other needed items. I want to go with the Edelbrock low profile intake and the Holley 550 or 600 carb. I'm just looking for the basic setup, nothing radicle. I'm not installing a new cam or anything, but I need to know the model numbers of the correct intake and carb and also an excelerator cable. I've checked several sites and there seems to be many different models. Any information or suggestions would be greatly appreciated.
 
I would try calling or going to the website of Ted Schumacher at TSImported automotive, or maybe the wedgeshop.
 
Either of the above suppliers will no doubt supply what you need. I bought my conversion as a complete kit from the Wedgeshop. Much easier than trying to put the pieces together yourself. Plus you get the benefit of support as necessary during the install. Plus we need to support the guys that support us, since the base of actual TR8 experts/suppliers is limited.
 
One of the guys in our Triumph Club recently converted his '80 TR8 to a 4-bbl. He bought a '63 Buick Skylark intake manifold on eBay for $70, paid $10 for 500-600 cfm 4-bbl + the cost of a rebuild kit, and bought an electric choke that bolted right on the carb for $25 locally. He fabricated the linkage himself for less than $10, so now has a complete 4-bbl set-up for under $125.

It is now incredibly fast compared to the stock Z-S, air pump, starved-for-air at 6,000 ft amsl, original condition. His next step is a set of headers, 2 (not 4) less restrictive mufflers, and a new set of catalytic converters.

The only problem is that his mpg has dropped considerably, mostly because he is having problems controlling his right foot. For some reason, it keeps hitting the floor on its own accord!!! :thumbsup:
 
I`v been studying up on how to select the right power valve and jetting for 5-600 Holley carbs for any engine. Having the right P.V. and right # squirter in the accelerator pump is about go fast, having the right jets is about crusing mileage. Too high of a numbered a power valve is about loosing that go fast feeling, to low a number is about loosing mileage. Too low numbered jets {lean}is about burnt valves and too high {Rich}is about loosing mileage and performance.
Note: Holley Jets are not numbered like standard number twist drills. DO NOT drill them out!
Too little squirt or too much squirt on the accelerator pump is about initial stumble on take off. Too lean on the idle circut can cause stumble too. The idle screws should be set for max idle then Rich 1/4 turn.
Incorrect float levels on these carbs will cause all sorts of symptoms. Floats should be set so that fule just barely weeps out of sight hole. JUNK kits with JUNK needle and seats are problematic with these carbs, ONLY use HOLLEY kits when rebuilding them! A simple vacume guage will tell you almost all you need to know when diagnosing these carbs, IF you have an O2 sensor all the better. If so select your jets by choosing the jet size for 4 - 700 Mv With a standard volt/ohm meter during cruise speed. The P.V. should be 2 Hg below max vacume at idle { In gear for auto trans } AND 2Hg below max vacume at cruise speed going up a slight incline.
Example: if you have 10 Hg at idle and cruise select P.V. 8.5 for milage or 7.5 for go fast at a sacrifice of some mileage.
Or an average of both combined if not the same.
You can even go lower for go fast but only to a point, once you reach that point your engine will not idle smoothly at all, and your milage will suffer the lower you go.
The squirter nozzles can be changed to give a larger or smaller shot whichever is needed. So can the squirter activaion levers. For Holleys with vacume secondary the springs can be changed to activate the secondary venturis at what ever RPM desired Manual secondarys are just that, Manual.
Any other questions can be directed at me through my email {In my profile}

Just F.W.I.W. for those with Holly carbs or those thinking about trying one.
 
I posted on another thread a link to a craigs list an advert a guy is selling six buick 215's, some with four barrels, maybe he has a four barel manifold separate?
 
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