It just keeps getting better (and more expensive)

[JeffMcKC]

I think it would be fine to mount them on top like a set of Ron's Toilet Bowls. Jay the intakes dont run to dry at least on mine, I can say that at Idle, with a injector PW change, it takes over 6 seconds to see a AFR change happen. There is a lot of fuel to burn off and reversion going on.

I had a lot of guys telling me there was not any difference in throttle body placement two years ago and one is fine, now have changed their minds. Good luck with them, they are like a Carb Tunnel Ram put a lot of timing in them static.

[jaybnve]

I'm actually going away from the IR manifold because I think it is a bottleneck for my engine. Looking at the current sprint car small blocks, most of them use 3" throttle butterflies on each cylinder, and the butterflies on my old Hilborn setup (feeding 585 cubic inches) are only 2 7/16". A sheet metal intake with a plenum should, by all rights, be a lot better, and I'm looking forward to getting some dyno data on this over the summer.

My sheet metal EFI intake is built using two front mounted 90mm throttle bodies, for hood clearance reasons. I've been told that having the air turn corners is not as big of a deal as having air/fuel turn corners, and since the injectors are in the runners I'm hoping that I don't lose too much by not having the air come in from the top of the intake. But that would be another interesting experiment; it wouldn't be any big deal to make a new top plate for the manifold, for dyno purposes only, and mount some throttle bodies on top for comparison with the front mounted position. If I did that, do you guys think I could just mount the two 90mm throttle bodies on top, or would I need to go with two 4-hole throttle bodies to get the best results?

[CDMBill]

I became curious as Kasse has an IR manifold for the Boss 429 stuff he is selling now which has cast in plenum under valley tray area connected by individually drilled passages into the port floors. And, Jay Brown's Injected cammer obviously works well.

My general survey of combinations and inquires with some of the aftermarket sheet metal manifold companies seems to confirm the idea that the two TB's on a more or less conventional tunnel ram is the best way to go. Makes for a tall hood though. Not that I would go that route or anything.

We'll see what turns up at DW.

[JeffMcKC]

I think you need a plenum on a N/A engine and air does not like to turn

[CDMBill]

As long as we're having fun, IR manifold (think traditional injector stacks) vs. dual four barrel TB on Tunnel Ram vs. front facing throttle body plenum on Tunnel ram base? All EFI.

[JeffMcKC]

NO

[CDMBill]

So, will a tunnel ram equipped EFI motor work equally well with a single 2200 CFM TB as it does with dual 1180 CFM TB's?

[JeffMcKC]

Those are a killer

[CDMBill]

I have buddy who just recently set a single pot 125 CC Bike record at Bonneville. He has similar kinda wall of decorations and few tribute photos.

My deal has improved a bit the cylinder walls are pristine and the cam lobe looks like it can buffed out as it has just few tiny scratches. So now onto the replacement parts and inevitable upgrades "as long as its apart..."

[fabricatordave]

you need to build one of these Bill.

Houston

good movie worlds fastest indian

[biginch]

you need to build one of these Bill.

Houston

[TheSilverBuick]

I forgive you for bringing the truck instead of the car

[CDMBill]

the valve train parts are consumables essentially especially in a Drag Week style context. Given what might have been I'm lucky as it was a last minute decision to take my truck on the CC Anti Tour instead of the car. Could easily have happened at freeway speeds 150 miles from home. Now for the 'as long as I'm doing this I might as well do that" part.

[Dignlif]

better in driveway than driving

Sucks that it happened at all but at least it was in your driveway and not on the road. A dropped or misguided valve could have caused a bunch more work and expense. I am finally learning that the valve train is often the hardest working component set so looking only at price, which I often wind up doing, can be detrimental. I haven't gone to your level Bill and Jeff but I certainly spent more coin than I originally wanted to for some peace of mind.

[JeffMcKC]

They all go bad. LOL The ones that don't, have a mild lobe and a Hydraulic Roller. Bill has the right perspective, Solid rollers are race only and if he got 9000/12000 passes out of them, they where used up.