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I think 20 hp can be gained just by tuning.
Start with the carb.
I know it seems too big but maybe the secondaries can be adjusted to open later. Finding the optimal fuel air ratio will help. So a good AFR gauge will be a big help.
Get the distributor tuned.
Try different carb spacers.
Try a set of 1.7 rocker arms.

You can also try changing the camshaft timing with an adjustable timing set. I think it would respond well to being a few degrees retarded. But might also hurt the overall peak rpm.

I don’t think the cam is a horrible choice. Very similar profile to what I’m using although mine has more duration and lift on the exhaust side. Which is generally preferred for a SBF.
The OP could try only getting 1.7 rockers for the exhaust only. This would also increase the duration and lift of the exhaust valves.
 

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Discussion Starter #63 (Edited)
Hey VMF -

Getting the bung installed and an AFR meter. Getting it on the calendar for next week. Before spending anymore excess funds - going to see what is going on w/AFR. Seems like a logical to me and then a tune.

I decided to use the google machine and ask it how to build a 300+HP 302. Many recipes for this build. Looking at some them - it appears I've checked off several boxes.but I'm def CARB heavy. Will try and make it work (hate to loose the spend). Suppose I can roll back to my EDEL 600. Sitting in box in my garage.

And I'm checking out manufacturer websites for CAM/Lifter kits just in case.

### Quick Edit ###

Looking at Edelbrock page (since my top end is EDEL) and their CAM spec sheets and performance tests - I think I'm off of my CAM selection. My COMP specs don't match up to their "recommend" specs to achieve certain performance levels.

Also shot off an inquiry to COMP giving them my build specs.
 

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Discussion Starter #65
Doing some contingency planning here..

If I must go the Carb route, I spent a few minutes pulling Carb inventory from my garage. I have on hand

EDEL 1405 (600CFM) - This just came off my car. Never was pleased with it. Probably because it was tuned properly.

Holley 1850-3 (600CFM). This was on my car in 2003 when I bought it. Came off in 2004 and has been sitting in a box.

Or I can step down to the QF650 and sell the 750. Wonder what the market is for the 750.

Thanks
J
 

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The 1850 is a good basic carb, or it used to be. They've been around a long time, I bought one in 1968 to go on a '67 289 and it was great right out of the box. Holley may have cheapened them a little since I bought mine. I used a Holley 650 DP on a 331 with a Vic jr and it worked well after leaning it out a little during dyno tuning.
 

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You should get a regular gold-colored Holley 650 Double Pumper if you're actually going to change carbs. Do it once, do it right.

As far as having 20hp in tuning, I got 16. But there is also margin for error between pulls due to differences in temp and so on. The AF was pretty good and totally flat even with an out of the box carb on the initial pull, the changes were very, very minor.

Wonder what the market is for the 750.
Probably good, it came off a good running car. That's usually what people want to know.
 

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Discussion Starter #68
Thanks jdub.

So here are some pics of the current quick fuel. I really like the look of it and the fact its chokeless. I an deal without a choke here in SC. Also wanted to show off that cool throttle linkage.

I've done a quick look and couldn't find the Holley 650 without a choke. Below is what I found:


QuickFuel

and

Holley

I imagine my fuel line setup should work in either or. I suspect it won't make much of a diff and I hear really good things about the QF

thoughts?
 

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Thanks jdub.

So here are some pics of the current quick fuel. I really like the look of it and the fact its chokeless. I an deal without a choke here in SC. Also wanted to show off that cool throttle linkage.

I've done a quick look and couldn't find the Holley 650 without a choke. Below is what I found:


QuickFuel

and

Holley

I imagine my fuel line setup should work in either or. I suspect it won't make much of a diff and I hear really good things about the QF

thoughts?
https://www.summitracing.com/parts/hly-0-80541-1/overview/
 

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Discussion Starter #71
Holy crud - $672 versus 500$

LOL
 

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Discussion Starter #72
Just put the Holley 1850, Edelbrock 1405 and two sets of cylinder heads (cores) - C5AE (non-HiPO) and D80E up for sale on my local Craigs List. I also listed the QF-750 as well to see what happens. HMU on PM if interested.


Trying to post on the for sale forum here however I don't seem to have access to do that. Can any admins help me out with that?
 

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Just put the Holley 1850, Edelbrock 1405 and two sets of cylinder heads (cores) - C5AE (non-HiPO) and D80E up for sale on my local Craigs List. I also listed the QF-750 as well to see what happens. HMU on PM if interested.


Trying to post on the for sale forum here however I don't seem to have access to do that. Can any admins help me out with that?
Because you haven’t reached the minimum number of posts.
 

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Try calling Edelbrock tech support. They have a virtual engine dyno and the guy will plug in your specs from your original cam. Then ask if a performer RPM cam will help, roller or flat tappet. I respect them because the waived me off on two separate calls: 1) Will an Airgap be a good expenditure. 2) would their performer RPM roller cam be a good expenditure? Both times they said the difference would be negligible and not a good use of money. Impressive!



I have been very happy with the RPM system, very flat torque curve on a 351. Pulls hard from 2500 through 5500 before gently rolling off. Still pulling very hard at 6000 when I hit the rev limiter. Cannot tell you how many autocrosses a year I run the last gates with the rev limiter in full action.


I run a 4150 650 Double pump which gives amazing throttle response but is a gas guzzler. Its made for racing - the Holley performance book suggests vacuum secondaries for any street car. They are great for set and forget for years.
 

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Discussion Starter #77
.....I run a 4150 650 Double pump which gives amazing throttle response but is a gas guzzler. Its made for racing - the Holley performance book suggests vacuum secondaries for any street car. They are great for set and forget for years.
Thanks for the feeback. Was planning on ringing them on Monday.

I got a hit on my CL add for the QF 750 CFM. I'll take a 60$ loss on it but I'd get enough out of it to put the QF 650 on it. They are available in mechanical or vacuum secondaries. Seems like the right thing to do.
 

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I personally like a double pumper on the street for the throttle response (if it is set up correctly).
For low bucks the Summit (Holley 4010) carbs are pretty good once you change the calibration.
The 750 DP version I am currently using was jetted quite rich. After cleaning it out and changing the jets down to 72, it was good.
 

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Discussion Starter #80
Update and another question....

I ordered my AFR gauge kit. Should be here this week.

Question - how important is it to have a fuel pressure gauge inline with the pump and carb? How important is it to have it. I'm currently running a summit fuel pump with max pressure 8psi and 110gph. Seems like a low cost "while I'm at it" that gives additional insight to performance and another touch point for troubleshooting. I think my carb is looking for 6'ish PSI which seems to set itself if you have the floats set correctly.

Thanks
J
 
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